The multifunctional secondary metabolites known as cyclic lipopeptides(CLPs),which are produced by a large variety of bacteria,have become a key category of plant immunity elicitors.Pseudomonas-CLPs(PsCLPs)are extreme...The multifunctional secondary metabolites known as cyclic lipopeptides(CLPs),which are produced by a large variety of bacteria,have become a key category of plant immunity elicitors.Pseudomonas-CLPs(PsCLPs)are extremely diverse in structure and biological activity.However,an understanding of CLP-plant structure–function interactions currently remains elusive.Here,we identify medpeptin,a novel CLP from Pseudomonas mediterranea that consists of 22 amino acids.Medpeptin is synthesized by a non-ribosomal peptide synthase(NRPS)gene cluster and regulated by a quorum-sensing system.Further research indicates that medpeptin does not exhibit antimicrobial activity;instead,it induces plant cell death immunity and confers resistance to bacterial infection.Comparative transcriptome analysis and virus-induced gene silencing(VIGS)reveal a set of immune signaling candidates involved in medpeptin perception.Silencing of a cell-wall leucine-rich repeat extensin protein(NbLRX3)or a receptor-like protein kinase(NbRLK25)—but not BAK1 or SGT1—compromises medpeptin-triggered cell death and resistance to pathogen infection in Nicotiana benthamiana.Our findings point to a noncanonical mechanism of CLP sensing and suggest perspectives for the development of plant disease resistance.展开更多
Listeria monocytogenes is a worrisome food-borne pathogen threatening global food safety.Our previous study proved that lipopeptide brevilaterin B showed efficient antibacterial activity against L.monocytogenes by int...Listeria monocytogenes is a worrisome food-borne pathogen threatening global food safety.Our previous study proved that lipopeptide brevilaterin B showed efficient antibacterial activity against L.monocytogenes by interacting with the cell membrane.This research further explored the antibacterial mechanism of brevilaterin B against L.monocytogenes at the sub-minimum inhibition concentration via transcriptomic analysis.Brevilaterin B induced growth inhibition rather than direct membrane lysis in L.monocytogenes at the minimum inhibitory concentration.Transcriptomic analysis showed 1779 difference expressed genes,including 895 up-regulated and 884 down-regulated genes.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis indicated that brevilaterin B influenced multiple pathways of L.monocytogenes,including peptidoglycan biosynthesis,membrane transport(ATP-binding cassette transports,ion transport),cellular metabolism(amino acid and lipid metabolism),ATP synthesis,and activation of the stress response(quorum sensing and bacterial chemotaxis).In conclusion,brevilaterin B affects gene expression related to biosynthesis,transport and stress response pathways on the membrane of L.monocytogenes.The present work provides the first transcriptomic assessment of the antibacterial mechanism of lipopeptide brevilaterin B at the gene level.展开更多
Solid-state fermentation has certain advantages in improving the yield of lipopetide, Box-Behnken Design（BBD） was adopted to optimize the producing condition of the antibacterial lipopetide produced by Bacillus natt...Solid-state fermentation has certain advantages in improving the yield of lipopetide, Box-Behnken Design（BBD） was adopted to optimize the producing condition of the antibacterial lipopetide produced by Bacillus natto in this article. The optimal solid state fermentation conditions were obtained： 10 g solid medium（7 g of wheat bran, 3 g of soybean meal） with appropriate inorganic salt（glucose 0.67%,sodium glutamate 0.64%,（NH4）2SO40.15%, K2HPO40.10%）; moisture content 123.78%; inoculation amount 10%; cultivation temperature 36.75 ℃ and cultivation time 72.4 h. The maximum production of lipopetide is 61.76 mg/gds under such conditions. This is the first report on the optimization of lipopeptide fermentation conditions in solid-state fermentation by wheat bran and soybean meal with Bacillus natto NT-6 strain, and will contribute to the development of lipopetide production.展开更多
Lipopeptides are currently re-emerging as an interesting subgroup in the peptide research field, having historical applications as antibacterial and antifungal agents and new potential applications as antiviral, antit...Lipopeptides are currently re-emerging as an interesting subgroup in the peptide research field, having historical applications as antibacterial and antifungal agents and new potential applications as antiviral, antitumor, immune-modulating and cell-penetrating compounds. However, due to their specific structure, chromatographic analysis often requires special buffer systems or the use of trifluoroacetic acid, limiting mass spectrometry detection. Therefore, we used a traditional aqueous/acetonitrile based gradient system, containing 0.1% （m/v） formic acid, to separate four pharmaceutically relevant lipopeptides （polymyxin B1, caspofungin, daptomycin and gramicidin A1）, which were selected based upon hierarchical cluster analysis （HCA） and principal component analysis （PCA）.In total, the performance of four different C18 columns, including one UPLC column, were evaluated using two parallel approaches. First, a Derringer desirability function was used, whereby six single and multiple chromatographic response values were rescaled into one overall D-value per column. Using this approach, the YMC Pack Pro C18 column was ranked as the best column for general MS-compatible lipopeptide separation. Secondly, the kinetic plot approach was used to compare the different columns at different flow rate ranges. As the optimal kinetic column performance is obtained at its maximal pressure, the length elongation factor λ（Pmax/Pexp） was used to transform the obtained experimental data （retention times and peak capacities） and construct kinetic performance limit （KPL） curves, allowing a direct visual and unbiased comparison of the selected columns, whereby the YMC Triart C18 UPLC and ACE C18 columns performed as best. Finally, differences in column performance and the （dis）advantages of both approaches are discussed.展开更多
MALDI-TOF-MS technology was used for identification of lipopeptide antibiotics producedby GEB3 strain, a derivative of Bacillus subtilis 168 which was transformed by lpaB3gene. The result showed GEB3 only produced lip...MALDI-TOF-MS technology was used for identification of lipopeptide antibiotics producedby GEB3 strain, a derivative of Bacillus subtilis 168 which was transformed by lpaB3gene. The result showed GEB3 only produced lipopeptide antibiotic surfactin. The analysisby LC-MS demonstrated that GEB3 produced standard surfactin isoforms with side chainlengths of 13,14 and 15 carbon atoms. The bioactivity detection of surfactin indicatedthat the surfactin produced by GEB3 had inhibition effect on plant pathogens Rhizoctoniasolani and Pyricularia oryzae.展开更多
Agricultural application studies, including field experiments and acute toxicity tests, were conducted for lipopeptides secreted by marine-derived Bacillus marinus B-9987. Benefiting from commercially available scaled...Agricultural application studies, including field experiments and acute toxicity tests, were conducted for lipopeptides secreted by marine-derived Bacillus marinus B-9987. Benefiting from commercially available scaled-up lipopeptide purification, the sample of impurities（isolated from target lipopeptides）, raw extracted sample（purity： 9.08%）, partially purified sample（purity： 20.86%）, and highly purified sample（purity： 87.51%） were prepared from B. marinus B-9987 fermentation broth, and used in lab-scale antagonism tests, field experiments, swarming motility tests, and acute toxicity tests. Operations and conditions in field experiments were consistent with the Pesticide-Guidelines for the Field Efficacy Trials（GB/T 17980.28-2000）, and acute toxicity tests were executed according to Toxicological Test Methods of Pesticides for Registration（GB 15670-1995）. In agar diffusion tests in vitro and pot tests in vivo, all lipopeptide samples with different purities significantly inhibited Botrytis cinerea; meanwhile the sample of impurities isolated from target lipopeptides were not effective against B. cinerea. Results of lab-scale tests showed that the target lipopeptides were effective substances against B. cinerea. Thus, partially purified and raw extracted samples were used in field experiments instead of the highly purified sample for cost saving. In the field experiments against rose grey mold, biological control efficacy of 500 mg L–1 lipopeptides reached 67.53%, slightly lower than 74.05% reached by the agrochemical pyrimethanil. However, pyrimethanil severely suppressed B. marinus B-9987, whereas the lipopeptides promoted swarming motility and biocontrol efficacy of Bacillus biomass. Lipopeptides at 87.51% purity were tested for systemic acute toxicity and confirmed as low-toxicity substances. In conclusion, low-toxicity lipopeptides were potential alternatives to agrochemicals, and they also performed good promotion when combined with homologous biological control microorganism. There were 2 breakthroughs in this research：（1） marine-derived bacterial lipopeptides inhibited grey mold caused by B. cinerea in field experiments; and（2） purified bacterial lipopeptides（sample purity： 〉87.51%） were determined to be low-toxicity substances by systemic acute toxicity tests, satisfying the strict requirement of pesticide registration in China（required purity： 〉85%）. This study provides support for using extracellularBacillus-derived lipopeptides commercially similar to Bacillus-based biological control agents.展开更多
The science and technology interact with the art in several ways. Biotechnological coupled with analytical approaches can play an important role in protecting and preserving cultural heritage for future generations. M...The science and technology interact with the art in several ways. Biotechnological coupled with analytical approaches can play an important role in protecting and preserving cultural heritage for future generations. Many microorganisms influenced by environmental conditions are the main responsible for biological contamination in built heritage. Biocides based on chemical compounds have been used to mitigate this problem. Thus, it is vitally important to develop proper remediation actions based on environmentally innocuous alternative. Bacillus specie is emerging as an optimistic alternative for built heritage treatment due to their capacity to produce secondary metabolites with antagonistic activities against many fungal pathogens. Therefore, the intent of this work was to access a rapid evaluation of antifungal potential of bioactive metabolites produced by Bacillus strains and simultaneously their characterization using spectroscopic (NMR) and chromatographic techniques (LC-ESI-MS). The high antifungal activity obtained for Bacillus sp. active compounds produced in this study confirms the great potential to suppress biodeteriogenic fungi growth on historical artworks. Additionally, the proposed methodology allowed to access bioactive metabolites produced without need of the laborious total previous isolation and could be used as a viable alternative to be employed for screening and production of new green biocides.展开更多
The molar absorption coefficients of each of 14 kinds of amino acids were determined by the spectrophotometric method, and the mean molar absorption coefficients of 37 different mixtures of each with amino acid compos...The molar absorption coefficients of each of 14 kinds of amino acids were determined by the spectrophotometric method, and the mean molar absorption coefficients of 37 different mixtures of each with amino acid composition exactly equivalent to that of the peptide chain of the corresponding lipopeptide were determined based on calculation or experimental. The significance of the results is that the mean molar absorption coefficients strongly demonstrate the regular patterns, though different amino acids bear quite different molar absorption coefficients.展开更多
This paper describes the synthesis of peptide fragments for use in a new type of combinatorial discovery technology, in which the building blocks are brought together by non-covalent interactions, rather than direct c...This paper describes the synthesis of peptide fragments for use in a new type of combinatorial discovery technology, in which the building blocks are brought together by non-covalent interactions, rather than direct chemical bonding. The building blocks of interest—in this case different amino acids—are converted to amphiphiles by attachment to lipid tails. The amphiphiles, when mixed together in aqueous phase, are designed so that they aggregate spontaneously to form micelles. The building blocks form the headgroups of each of the amphiphiles, and these headgroups cover the surface of the micelle in a dynamic close-packed fluid mosaic array. These building blocks come together so closely that two- or three-dimensional structures are created on the surface of the micelles, and these can be screened in biological assays to find out which combination of building blocks is able to elicit a biological response. Lipopeptides consisting of two residues of lipoamino acid and other amino acids moieties have been designed, synthesized, characterized and the ability of these constructs to form supra-molecular assemblies is demonstrated.展开更多
In biological controls using <em>Bacillus</em> spp., cyclic lipopeptides play a role as elicitors to induce disease resistance on various host plants. However, it is still unclear the specificity between c...In biological controls using <em>Bacillus</em> spp., cyclic lipopeptides play a role as elicitors to induce disease resistance on various host plants. However, it is still unclear the specificity between cyclic lipopeptides and host plants to induce disease resistance. In this study, we aimed to clarify the specificity to induce disease resistance among cyclic lipopeptides on various host plants. Our data clearly showed both cyclic lipopeptides conferred disease suppression on most of host plants, but at different range of cyclic lipopeptide concentration. Our findings contribute to understanding the complex on the specificity of cyclic lipopeptide derived induced disease resistance.展开更多
The integrated lipopeptide(RVA)/gene complexes are fabricated with bi-directional regulation on tumor cells and micro-environment.After self-assembling and target coating modification,the poly(γ-glutamic acid)(γ-PGA...The integrated lipopeptide(RVA)/gene complexes are fabricated with bi-directional regulation on tumor cells and micro-environment.After self-assembling and target coating modification,the poly(γ-glutamic acid)(γ-PGA)/RVA nano-vectors can sequentially respond to pH&redox stimuli,and guarantee efficient therapeutic gene delivery and control release of all-trans retinoic acid.The design provides a facile but promising strategy to treat refractory cancers.展开更多
Lysobacter harbors a plethora of cryptic biosynthetic gene clusters(BGCs),albeit only a limited number have been analyzed to date.In this study,we described the activation of a cryptic polyketide synthase(PKS)/nonribo...Lysobacter harbors a plethora of cryptic biosynthetic gene clusters(BGCs),albeit only a limited number have been analyzed to date.In this study,we described the activation of a cryptic polyketide synthase(PKS)/nonribosomal peptide synthetase(NRPS)gene cluster(lsh)in Lysobacter sp.DSM 3655 through promoter engineering and heterologous expression in Streptomyces sp.S001.As a result of this methodology,we were able to isolate two novel linear lipopeptides,lysohexaenetides A(1)and B(2),from the recombinant strain S001-lsh.Furthermore,we proposed the biosynthetic pathway for lysohexaenetides and identified LshA as another example of entirely iterative bacterial PKSs.This study highlights the potential of heterologous expression systems in uncovering cryptic biosynthetic pathways in Lysobacter genomes,particularly in the absence of genetic manipulation tools.展开更多
Chromatographic separation of the marine-derived bacterium Bacillus licheniformis resulted in the isolation of two new cyclic lipopeptides named ai-Cl6 surfactin （1） and ai-Cl4 surfactin （2）, together with iso-Cm5...Chromatographic separation of the marine-derived bacterium Bacillus licheniformis resulted in the isolation of two new cyclic lipopeptides named ai-Cl6 surfactin （1） and ai-Cl4 surfactin （2）, together with iso-Cm5 surfactin and iso-Cl6 surfactin. The structures of the new cyclic lipopeptides were determined through extensive spectroscopic analysis. The sequences of the amino acids in cyclic nucleus were established by the ESI-MS/MS fragmentation, which provided an efficient method to detect lipopeptides from bacterium extracts without senaration展开更多
Microbial lipopeptides play an important role in apoptosis induction of tumor cells.However,there is little knowledge about the relationship between apoptosis induction and membrane fatty acids.The present study focus...Microbial lipopeptides play an important role in apoptosis induction of tumor cells.However,there is little knowledge about the relationship between apoptosis induction and membrane fatty acids.The present study focused on the effects of lipopeptides produced by Bacillus subtilis HSO121 on Bcap-37 cell lines.3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl(MTT)colorimetric assay and surface tension measurements,showed that the critical micelle concentration(CMC)was a critical level for the inhibitory activity of lipopeptides on the growth of Bcap-37 cells.Under the CMC,the order of least to greatest cytotoxicity effect on cancer cell lines by lipopeptides is C13-lipopeptide<C14-lipopepitde<C15-lipopeptide.Above CMC,all lipopeptides directly exert cytolytic activity.The flow cytometric analysis and Hoechst33258 staining experiments confirmed the apoptosis of Bcap-37 cell lines induced by lipopeptides in a dose-dependent manner.This apoptosis was associated with a significant decrease of the unsaturated degree of the cellular fatty acids of Bcap-37 cell lines due to the changes in the cellular fatty acids composition induced by the lipopeptide treatment.These results indicated that disturbance of the cellular fatty acid composition of breast cancer cell lines were related to in the cell apoptosis.Furthermore,significant difference in IC50 values of tumor cells and normal cell showed that the lipopeptide exerted selective cytotoxicity on the cancer cells.Thus HSO121 lipopeptides may have potential applications as an anticancer leads.展开更多
We describe an application of carrier protein-free strategy in constructing a fully synthetic methamphetamine(METH)vaccine that contains three components:Toll-like receptor 2 ligand,Th2 epitope,and METH hapten.The imm...We describe an application of carrier protein-free strategy in constructing a fully synthetic methamphetamine(METH)vaccine that contains three components:Toll-like receptor 2 ligand,Th2 epitope,and METH hapten.The immunological evaluation in mice revealed high titers of METH-specific antibodies induced by the construct and the activation of humoral immunity that would be beneficial for neutralization and clearance of the METH molecule.Behavio ral experiments indicated that the synthetic vaccine attenuated the acquisition of METH-induced conditioned place preference and inhibited the initiation and expression of METH-induced locomotor sensitization.These results demonstrate that the lipopeptide-based vaccine has invo ked an immune response and showed the potential of preventing the rewarding and psychoactive effects of METH.展开更多
Bacillus subtilis N-2 which was isolated from natto,produced lipopeptides using soybean meal as a substrate.This work aimed to purify,identify,and determine the antibacterial mechanism of lipopeptides produced by B.su...Bacillus subtilis N-2 which was isolated from natto,produced lipopeptides using soybean meal as a substrate.This work aimed to purify,identify,and determine the antibacterial mechanism of lipopeptides produced by B.subtilis N-2.The fermented product obtained by solid-state fermentation was subjected to water extraction,acid precipitation,and methanol extraction.Fractions were separated and collected using a two-step ultrafiltration method and then identified by LC-MS/MS.Mass spectrometry characterization revealed the presence of four variants of iturin A that differed according to the p-amino fatty acid chain from C14 to C17 as well as the amino acid positions.A new lipopeptide(m/z 1070.3)was identified and its structure was different from the previously reported lipopeptides.The lipopeptides were shown to inhibit the growth of an isolate of Pseudomonas putida,a common pathogen in decaying fish,by changing membrane permeability.These results suggest that the lipopeptides from B.subtilis N-2 could be used as a biocontrol agent in aquaculture.展开更多
Nonribosomal peptide synthase(NRPS)is a unique molecular assembly mechanism with high hybridity.Its recombination is conducive to the development of novel lipopeptides.However,there are few reports on NRPS subunit rec...Nonribosomal peptide synthase(NRPS)is a unique molecular assembly mechanism with high hybridity.Its recombination is conducive to the development of novel lipopeptides.However,there are few reports on NRPS subunit recombination of plipastatin at present.In this paper,plipastatin synthase was modified by the forward movement of subunit PPSE and the replacement of the communication-mediating(COM)domain.The results showed that ppsABE,a new assembly line,could synthesize novel lipopeptides such as cycle pentapeptide(C16-18β-OHFA-E-O-cyclo(Y-T-I),and its antimicrobial activity against Rhizopus stolonifer and Staphylococcus aureus was better than that of plipastatin.However,the reactivity of ppsABCE disappeared,but the substitution of COM^(D)_(ppsC)/COM^(A)_(ppsD) or COM^(D)_(ppsD)/COM^(A)_(ppsE) for COM^(D)_(ppsC)/COM^(A)_(ppsE) could restore its activity and conduct the biosynthesis of linear hexapeptide(C16-17β-OHFA-E-O-Y-T-E-A/V)and heptapeptide(C17-18β-OHFA-E-O-Y-T-E-A-I).Collectively,these findings indicated that the COM donor domain at the C-terminus of PPSB could communicate with the COM acceptor domain at the N-terminus of PPSE and that the compatible COM domain is an important tool for communication between nonpartner subunits.Moreover,the integrity and selective compatibility of the COM acceptor domain of subunit PPSE are essential to promote the interaction between PPSE and other subunits.This work further complemented the rules of NRPS subunit recombination and provided a theoretical basis for the development of novel high-efficiency lipopeptides.展开更多
Lipopeptides are recognized as a structurally diverse group of functional biopeptides.They possess multiple biological,biotechnological and therapeutic applications and are able to affect cell membrane integrity and p...Lipopeptides are recognized as a structurally diverse group of functional biopeptides.They possess multiple biological,biotechnological and therapeutic applications and are able to affect cell membrane integrity and permeability.It is widely accepted that suppressing the interaction of redooxidation is mainly aimed by inserting functional biopeptides on form alpha-helical peptides or on form antibody.Such types of structured biomaterials have great potential in promoting signal transductions to the most organelles having geometrical and spacial structures similar to endogenous liposome forms such as lysosomes,ribosomes,mitochondria and platelets..Thus,inserting radioactive trace-elements along with biopeptides is necessary in tracing the trajectory of those radioactive micelles that are destined in targeting further complicated disease and growth factor propagation.These techniques are important in determining structure-symmetry and asymmetry leading to meso-spherical crystal-packing modes or to copolymer vesiculization.The main objective of this review is to highlight and elucidate the potential role of lipopeptides in promoting signals at surface/interface of micelles along with their functionalities in repairing cellular and nuclear damages.Moreover,state-of-the-art scientific knowledge is reviewed regarding bioconjugation and structuring charged-mono-layer and/or bi-layer phospholipidic membranes in adherent to signal-biopeptides using some advanced techniques such as ultra-sound probe based polydispersity of radioactive trace-elements assisted microdialysis as micro-separating techniques in between those miscible and immiscible compounds.展开更多
Fusarium dry rot is considered to be the most critical soilborne and postharvest disease that damages potato tubers worldwide when they are stored for a long time.This study was performed to demonstrate the effect of ...Fusarium dry rot is considered to be the most critical soilborne and postharvest disease that damages potato tubers worldwide when they are stored for a long time.This study was performed to demonstrate the effect of crude extract,culture filtrate,and cell suspension obtained from the bacterium Bacillus subtilis Hussain T-AMU,on the net house and field.From oil-contaminated soil,through the serial dilution method,biosurfactant bacteria were isolated on nutrient agar medium.To isolate and screen the prospective biosurfactant strain,various biosurfactant screening methods were used.Standard protocols were carried out for morphological,molecular,and chemical characterization.The disease incidences were significantly decreased under net house and field conditions after treatment with biosurfactant extract(20%,70%),culture filtrate(23%,49%),and bacterial cell suspension(46%,27%),respectively.These results indicate a significant effect of B.subtilis HussainT-AMU against Fusarium oxysporum.The characterization of the partially purified extract by gas-chromatography indicated the existence of a high amount of methyl ester fatty acids.The quantitative analysis determined the presence of lipopeptide-surfactin,fengycin,and iturin in the biosurfactant extract.Scanning electron microscopy revealed that morphological variation was revealed in the structure of stomata size in leaves and in the mycelia of the pathogen that was investigated.This promising biocontrol agent can be a plausible option for further research and can also be used for the production of green biomolecules at an additional industrial level.展开更多
Objective:To characterize the pharmacological importance of biosurfactants isolated from halophilic Bacillus sp BS3.Methods:Halophilic Bacillus sp.BS3 was isolated from solar salt works,identified by 16S rRNA sequenci...Objective:To characterize the pharmacological importance of biosurfactants isolated from halophilic Bacillus sp BS3.Methods:Halophilic Bacillus sp.BS3 was isolated from solar salt works,identified by 16S rRNA sequencing and was used for screening their biosurfactant production.Characters of the biosurfactant and their anticancer activity were analyzed and performed in mammary epithelial carcinoma cell at different concentrations.Results:The biosurfactant were characterized by TLC,FTIR and GC-MS analysis and identified as lipopeptide type.GC-MS analysis revealed that,the biosurfactant had various compounds including 13Docosenamide.(Z);Mannosamine,9- and N,N,N',N'-tetramethyl.Surprisingly the antiviral activity was found against shrimp white spot syndrome virus(WSSV) by suppressing the viral replication and significantly raised shrimp survival(P<0.01).Anticancer activity performed in the mammary epithelial carcinoma cell at different concentrations of biosurfactants,among the various concentrations of biosurfactants such as 0.000 25,0.002 5,0.025,0.25 and 2.5 μ g,the 0.25 μ g concentration suppressed the cells significantly(P<0.05) to 24.8%.Conclusions:Based on the findings,the present study concluded that,there is a possibility to develop eco-friendly antimicrobial and anticancer drugs from the extremophilic origin.展开更多
基金funded by the National Key R&D Program of China(2022YFD1901300)the National Natural Science Foundation of China(31901932)+2 种基金the Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences(CAAS-ZDRW202308 and Y2022PT12)the Beijing Innovation Consortium of Agriculture Research System(BAIC04-2022)the Science and Technology Programs of the Zunyi Tobacco(2021XM03)。
文摘The multifunctional secondary metabolites known as cyclic lipopeptides(CLPs),which are produced by a large variety of bacteria,have become a key category of plant immunity elicitors.Pseudomonas-CLPs(PsCLPs)are extremely diverse in structure and biological activity.However,an understanding of CLP-plant structure–function interactions currently remains elusive.Here,we identify medpeptin,a novel CLP from Pseudomonas mediterranea that consists of 22 amino acids.Medpeptin is synthesized by a non-ribosomal peptide synthase(NRPS)gene cluster and regulated by a quorum-sensing system.Further research indicates that medpeptin does not exhibit antimicrobial activity;instead,it induces plant cell death immunity and confers resistance to bacterial infection.Comparative transcriptome analysis and virus-induced gene silencing(VIGS)reveal a set of immune signaling candidates involved in medpeptin perception.Silencing of a cell-wall leucine-rich repeat extensin protein(NbLRX3)or a receptor-like protein kinase(NbRLK25)—but not BAK1 or SGT1—compromises medpeptin-triggered cell death and resistance to pathogen infection in Nicotiana benthamiana.Our findings point to a noncanonical mechanism of CLP sensing and suggest perspectives for the development of plant disease resistance.
基金financially supported by the National Natural Science Foundation of China(31771951,32072199,31801510)the Beijing Natural Science Foundation(KZ201810011016).
文摘Listeria monocytogenes is a worrisome food-borne pathogen threatening global food safety.Our previous study proved that lipopeptide brevilaterin B showed efficient antibacterial activity against L.monocytogenes by interacting with the cell membrane.This research further explored the antibacterial mechanism of brevilaterin B against L.monocytogenes at the sub-minimum inhibition concentration via transcriptomic analysis.Brevilaterin B induced growth inhibition rather than direct membrane lysis in L.monocytogenes at the minimum inhibitory concentration.Transcriptomic analysis showed 1779 difference expressed genes,including 895 up-regulated and 884 down-regulated genes.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis indicated that brevilaterin B influenced multiple pathways of L.monocytogenes,including peptidoglycan biosynthesis,membrane transport(ATP-binding cassette transports,ion transport),cellular metabolism(amino acid and lipid metabolism),ATP synthesis,and activation of the stress response(quorum sensing and bacterial chemotaxis).In conclusion,brevilaterin B affects gene expression related to biosynthesis,transport and stress response pathways on the membrane of L.monocytogenes.The present work provides the first transcriptomic assessment of the antibacterial mechanism of lipopeptide brevilaterin B at the gene level.
基金Supported by the Public Research and Capacity Building Program of Guangdong Province(2014B020204005)the Higher Educational Cultivation Program for Major Scientific Research Projects of Guangdong Ocean University(2013050205,2014050203,2013050312)~~
文摘Solid-state fermentation has certain advantages in improving the yield of lipopetide, Box-Behnken Design（BBD） was adopted to optimize the producing condition of the antibacterial lipopetide produced by Bacillus natto in this article. The optimal solid state fermentation conditions were obtained： 10 g solid medium（7 g of wheat bran, 3 g of soybean meal） with appropriate inorganic salt（glucose 0.67%,sodium glutamate 0.64%,（NH4）2SO40.15%, K2HPO40.10%）; moisture content 123.78%; inoculation amount 10%; cultivation temperature 36.75 ℃ and cultivation time 72.4 h. The maximum production of lipopetide is 61.76 mg/gds under such conditions. This is the first report on the optimization of lipopeptide fermentation conditions in solid-state fermentation by wheat bran and soybean meal with Bacillus natto NT-6 strain, and will contribute to the development of lipopetide production.
基金funded by PhD grants of ‘Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen)’ (Nos. 101529 (MD) and 121512 (BG))The Special Research Fund (BOF) of Ghent University (01J22510 (EW) and 01D38811 (SS))
文摘Lipopeptides are currently re-emerging as an interesting subgroup in the peptide research field, having historical applications as antibacterial and antifungal agents and new potential applications as antiviral, antitumor, immune-modulating and cell-penetrating compounds. However, due to their specific structure, chromatographic analysis often requires special buffer systems or the use of trifluoroacetic acid, limiting mass spectrometry detection. Therefore, we used a traditional aqueous/acetonitrile based gradient system, containing 0.1% （m/v） formic acid, to separate four pharmaceutically relevant lipopeptides （polymyxin B1, caspofungin, daptomycin and gramicidin A1）, which were selected based upon hierarchical cluster analysis （HCA） and principal component analysis （PCA）.In total, the performance of four different C18 columns, including one UPLC column, were evaluated using two parallel approaches. First, a Derringer desirability function was used, whereby six single and multiple chromatographic response values were rescaled into one overall D-value per column. Using this approach, the YMC Pack Pro C18 column was ranked as the best column for general MS-compatible lipopeptide separation. Secondly, the kinetic plot approach was used to compare the different columns at different flow rate ranges. As the optimal kinetic column performance is obtained at its maximal pressure, the length elongation factor λ（Pmax/Pexp） was used to transform the obtained experimental data （retention times and peak capacities） and construct kinetic performance limit （KPL） curves, allowing a direct visual and unbiased comparison of the selected columns, whereby the YMC Triart C18 UPLC and ACE C18 columns performed as best. Finally, differences in column performance and the （dis）advantages of both approaches are discussed.
基金supported by the National Nature1 Science Foundation of China(30170623)the National 863 Program of China(2001AA246013).
文摘MALDI-TOF-MS technology was used for identification of lipopeptide antibiotics producedby GEB3 strain, a derivative of Bacillus subtilis 168 which was transformed by lpaB3gene. The result showed GEB3 only produced lipopeptide antibiotic surfactin. The analysisby LC-MS demonstrated that GEB3 produced standard surfactin isoforms with side chainlengths of 13,14 and 15 carbon atoms. The bioactivity detection of surfactin indicatedthat the surfactin produced by GEB3 had inhibition effect on plant pathogens Rhizoctoniasolani and Pyricularia oryzae.
基金financially supported by the Key Technologies Research and Development Program of China(2011BAE06B04-16)
文摘Agricultural application studies, including field experiments and acute toxicity tests, were conducted for lipopeptides secreted by marine-derived Bacillus marinus B-9987. Benefiting from commercially available scaled-up lipopeptide purification, the sample of impurities（isolated from target lipopeptides）, raw extracted sample（purity： 9.08%）, partially purified sample（purity： 20.86%）, and highly purified sample（purity： 87.51%） were prepared from B. marinus B-9987 fermentation broth, and used in lab-scale antagonism tests, field experiments, swarming motility tests, and acute toxicity tests. Operations and conditions in field experiments were consistent with the Pesticide-Guidelines for the Field Efficacy Trials（GB/T 17980.28-2000）, and acute toxicity tests were executed according to Toxicological Test Methods of Pesticides for Registration（GB 15670-1995）. In agar diffusion tests in vitro and pot tests in vivo, all lipopeptide samples with different purities significantly inhibited Botrytis cinerea; meanwhile the sample of impurities isolated from target lipopeptides were not effective against B. cinerea. Results of lab-scale tests showed that the target lipopeptides were effective substances against B. cinerea. Thus, partially purified and raw extracted samples were used in field experiments instead of the highly purified sample for cost saving. In the field experiments against rose grey mold, biological control efficacy of 500 mg L–1 lipopeptides reached 67.53%, slightly lower than 74.05% reached by the agrochemical pyrimethanil. However, pyrimethanil severely suppressed B. marinus B-9987, whereas the lipopeptides promoted swarming motility and biocontrol efficacy of Bacillus biomass. Lipopeptides at 87.51% purity were tested for systemic acute toxicity and confirmed as low-toxicity substances. In conclusion, low-toxicity lipopeptides were potential alternatives to agrochemicals, and they also performed good promotion when combined with homologous biological control microorganism. There were 2 breakthroughs in this research：（1） marine-derived bacterial lipopeptides inhibited grey mold caused by B. cinerea in field experiments; and（2） purified bacterial lipopeptides（sample purity： 〉87.51%） were determined to be low-toxicity substances by systemic acute toxicity tests, satisfying the strict requirement of pesticide registration in China（required purity： 〉85%）. This study provides support for using extracellularBacillus-derived lipopeptides commercially similar to Bacillus-based biological control agents.
文摘The science and technology interact with the art in several ways. Biotechnological coupled with analytical approaches can play an important role in protecting and preserving cultural heritage for future generations. Many microorganisms influenced by environmental conditions are the main responsible for biological contamination in built heritage. Biocides based on chemical compounds have been used to mitigate this problem. Thus, it is vitally important to develop proper remediation actions based on environmentally innocuous alternative. Bacillus specie is emerging as an optimistic alternative for built heritage treatment due to their capacity to produce secondary metabolites with antagonistic activities against many fungal pathogens. Therefore, the intent of this work was to access a rapid evaluation of antifungal potential of bioactive metabolites produced by Bacillus strains and simultaneously their characterization using spectroscopic (NMR) and chromatographic techniques (LC-ESI-MS). The high antifungal activity obtained for Bacillus sp. active compounds produced in this study confirms the great potential to suppress biodeteriogenic fungi growth on historical artworks. Additionally, the proposed methodology allowed to access bioactive metabolites produced without need of the laborious total previous isolation and could be used as a viable alternative to be employed for screening and production of new green biocides.
基金This work was supported by the National Natural Science Foundation of China(No.50374038,50574040)Specialized Research Fund for the Doctoral Program of Higher Education(20030251002)+1 种基金Key Project of the Ministry of Education(03071)by the Department of Science and Technology Shanghai(045407017).
文摘The molar absorption coefficients of each of 14 kinds of amino acids were determined by the spectrophotometric method, and the mean molar absorption coefficients of 37 different mixtures of each with amino acid composition exactly equivalent to that of the peptide chain of the corresponding lipopeptide were determined based on calculation or experimental. The significance of the results is that the mean molar absorption coefficients strongly demonstrate the regular patterns, though different amino acids bear quite different molar absorption coefficients.
文摘This paper describes the synthesis of peptide fragments for use in a new type of combinatorial discovery technology, in which the building blocks are brought together by non-covalent interactions, rather than direct chemical bonding. The building blocks of interest—in this case different amino acids—are converted to amphiphiles by attachment to lipid tails. The amphiphiles, when mixed together in aqueous phase, are designed so that they aggregate spontaneously to form micelles. The building blocks form the headgroups of each of the amphiphiles, and these headgroups cover the surface of the micelle in a dynamic close-packed fluid mosaic array. These building blocks come together so closely that two- or three-dimensional structures are created on the surface of the micelles, and these can be screened in biological assays to find out which combination of building blocks is able to elicit a biological response. Lipopeptides consisting of two residues of lipoamino acid and other amino acids moieties have been designed, synthesized, characterized and the ability of these constructs to form supra-molecular assemblies is demonstrated.
文摘In biological controls using <em>Bacillus</em> spp., cyclic lipopeptides play a role as elicitors to induce disease resistance on various host plants. However, it is still unclear the specificity between cyclic lipopeptides and host plants to induce disease resistance. In this study, we aimed to clarify the specificity to induce disease resistance among cyclic lipopeptides on various host plants. Our data clearly showed both cyclic lipopeptides conferred disease suppression on most of host plants, but at different range of cyclic lipopeptide concentration. Our findings contribute to understanding the complex on the specificity of cyclic lipopeptide derived induced disease resistance.
基金financially supported by National Natural Science Foundation of China(NSFC,Nos.81873921 and 51903174)Sino-German Cooperation Group Project(No.GZ1512)+2 种基金China Postdoctoral Science Foundation(No.2021M702772)Chengdu Science and Technology Program(No.2020-GH02-00007-HZ)Sichuan University Postdoctoral Interdisciplinary Innovation Startup Foundation and the Fundamental Research Funds for Central Universities(No.2021SCU12070)。
文摘The integrated lipopeptide(RVA)/gene complexes are fabricated with bi-directional regulation on tumor cells and micro-environment.After self-assembling and target coating modification,the poly(γ-glutamic acid)(γ-PGA)/RVA nano-vectors can sequentially respond to pH&redox stimuli,and guarantee efficient therapeutic gene delivery and control release of all-trans retinoic acid.The design provides a facile but promising strategy to treat refractory cancers.
基金supported by the National Natural Science Foundation of China(Nos.81573311 and 82173702).
文摘Lysobacter harbors a plethora of cryptic biosynthetic gene clusters(BGCs),albeit only a limited number have been analyzed to date.In this study,we described the activation of a cryptic polyketide synthase(PKS)/nonribosomal peptide synthetase(NRPS)gene cluster(lsh)in Lysobacter sp.DSM 3655 through promoter engineering and heterologous expression in Streptomyces sp.S001.As a result of this methodology,we were able to isolate two novel linear lipopeptides,lysohexaenetides A(1)and B(2),from the recombinant strain S001-lsh.Furthermore,we proposed the biosynthetic pathway for lysohexaenetides and identified LshA as another example of entirely iterative bacterial PKSs.This study highlights the potential of heterologous expression systems in uncovering cryptic biosynthetic pathways in Lysobacter genomes,particularly in the absence of genetic manipulation tools.
基金Grants from COMRA(Grant No.DY125-15-T-01 and SOA(Grant No.2010319123366025-4)National High Technology Development Project(863 Project,Grant No.2011AA10A202-2)National Key Technologies R&D Program(Grant No.2011BAE06B04)
文摘Chromatographic separation of the marine-derived bacterium Bacillus licheniformis resulted in the isolation of two new cyclic lipopeptides named ai-Cl6 surfactin （1） and ai-Cl4 surfactin （2）, together with iso-Cm5 surfactin and iso-Cl6 surfactin. The structures of the new cyclic lipopeptides were determined through extensive spectroscopic analysis. The sequences of the amino acids in cyclic nucleus were established by the ESI-MS/MS fragmentation, which provided an efficient method to detect lipopeptides from bacterium extracts without senaration
基金This work was supported in part by grants from the National Natural Science Foundation of China(Nos.50574040,30700015)the Ministry of Science and Technology of China(2007CB707801)+3 种基金Shanghai Science and Technology Commission(No.071607014)China Postdoctoral Science Foundation(20080440545)the National Programs for High Technology Research and Development Program(863 Program)(No.2006AA09Z402)Key Project of International Cooperation(2007DFB31620).L.Z.is an awardee for Hundred Talents Program.
文摘Microbial lipopeptides play an important role in apoptosis induction of tumor cells.However,there is little knowledge about the relationship between apoptosis induction and membrane fatty acids.The present study focused on the effects of lipopeptides produced by Bacillus subtilis HSO121 on Bcap-37 cell lines.3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl(MTT)colorimetric assay and surface tension measurements,showed that the critical micelle concentration(CMC)was a critical level for the inhibitory activity of lipopeptides on the growth of Bcap-37 cells.Under the CMC,the order of least to greatest cytotoxicity effect on cancer cell lines by lipopeptides is C13-lipopeptide<C14-lipopepitde<C15-lipopeptide.Above CMC,all lipopeptides directly exert cytolytic activity.The flow cytometric analysis and Hoechst33258 staining experiments confirmed the apoptosis of Bcap-37 cell lines induced by lipopeptides in a dose-dependent manner.This apoptosis was associated with a significant decrease of the unsaturated degree of the cellular fatty acids of Bcap-37 cell lines due to the changes in the cellular fatty acids composition induced by the lipopeptide treatment.These results indicated that disturbance of the cellular fatty acid composition of breast cancer cell lines were related to in the cell apoptosis.Furthermore,significant difference in IC50 values of tumor cells and normal cell showed that the lipopeptide exerted selective cytotoxicity on the cancer cells.Thus HSO121 lipopeptides may have potential applications as an anticancer leads.
基金supported in part by the National Natural Science Foundation of China(Nos.81821092 and 81701312)Beijing Municipal Science and Technology Commission(Nos.Z181100001518005 and JQ.18024)National Key Research and Development Program of China(Nos.2017YFC0803608 and 2019YFC0118604)。
文摘We describe an application of carrier protein-free strategy in constructing a fully synthetic methamphetamine(METH)vaccine that contains three components:Toll-like receptor 2 ligand,Th2 epitope,and METH hapten.The immunological evaluation in mice revealed high titers of METH-specific antibodies induced by the construct and the activation of humoral immunity that would be beneficial for neutralization and clearance of the METH molecule.Behavio ral experiments indicated that the synthetic vaccine attenuated the acquisition of METH-induced conditioned place preference and inhibited the initiation and expression of METH-induced locomotor sensitization.These results demonstrate that the lipopeptide-based vaccine has invo ked an immune response and showed the potential of preventing the rewarding and psychoactive effects of METH.
基金supported by the National Key R&D Program of China(2017YFC1600703)the National Natural Science Foundation of China(31471657).
文摘Bacillus subtilis N-2 which was isolated from natto,produced lipopeptides using soybean meal as a substrate.This work aimed to purify,identify,and determine the antibacterial mechanism of lipopeptides produced by B.subtilis N-2.The fermented product obtained by solid-state fermentation was subjected to water extraction,acid precipitation,and methanol extraction.Fractions were separated and collected using a two-step ultrafiltration method and then identified by LC-MS/MS.Mass spectrometry characterization revealed the presence of four variants of iturin A that differed according to the p-amino fatty acid chain from C14 to C17 as well as the amino acid positions.A new lipopeptide(m/z 1070.3)was identified and its structure was different from the previously reported lipopeptides.The lipopeptides were shown to inhibit the growth of an isolate of Pseudomonas putida,a common pathogen in decaying fish,by changing membrane permeability.These results suggest that the lipopeptides from B.subtilis N-2 could be used as a biocontrol agent in aquaculture.
基金This study was supported by grants from the National Natural Science Foundation of China(Grant No.31972174)the National Key R&D Program of China(Grant No.2018YFC1602500).
文摘Nonribosomal peptide synthase(NRPS)is a unique molecular assembly mechanism with high hybridity.Its recombination is conducive to the development of novel lipopeptides.However,there are few reports on NRPS subunit recombination of plipastatin at present.In this paper,plipastatin synthase was modified by the forward movement of subunit PPSE and the replacement of the communication-mediating(COM)domain.The results showed that ppsABE,a new assembly line,could synthesize novel lipopeptides such as cycle pentapeptide(C16-18β-OHFA-E-O-cyclo(Y-T-I),and its antimicrobial activity against Rhizopus stolonifer and Staphylococcus aureus was better than that of plipastatin.However,the reactivity of ppsABCE disappeared,but the substitution of COM^(D)_(ppsC)/COM^(A)_(ppsD) or COM^(D)_(ppsD)/COM^(A)_(ppsE) for COM^(D)_(ppsC)/COM^(A)_(ppsE) could restore its activity and conduct the biosynthesis of linear hexapeptide(C16-17β-OHFA-E-O-Y-T-E-A/V)and heptapeptide(C17-18β-OHFA-E-O-Y-T-E-A-I).Collectively,these findings indicated that the COM donor domain at the C-terminus of PPSB could communicate with the COM acceptor domain at the N-terminus of PPSE and that the compatible COM domain is an important tool for communication between nonpartner subunits.Moreover,the integrity and selective compatibility of the COM acceptor domain of subunit PPSE are essential to promote the interaction between PPSE and other subunits.This work further complemented the rules of NRPS subunit recombination and provided a theoretical basis for the development of novel high-efficiency lipopeptides.
基金The authors acknowledge the INATAA Mentouri Constantine University of Algeria,University Putra Malaysia and Malaysian Palm Oil Board for further innovation and support to researches relevant to food crystallization,isomerization and copolymerization destined for enriching emulsions food products.
文摘Lipopeptides are recognized as a structurally diverse group of functional biopeptides.They possess multiple biological,biotechnological and therapeutic applications and are able to affect cell membrane integrity and permeability.It is widely accepted that suppressing the interaction of redooxidation is mainly aimed by inserting functional biopeptides on form alpha-helical peptides or on form antibody.Such types of structured biomaterials have great potential in promoting signal transductions to the most organelles having geometrical and spacial structures similar to endogenous liposome forms such as lysosomes,ribosomes,mitochondria and platelets..Thus,inserting radioactive trace-elements along with biopeptides is necessary in tracing the trajectory of those radioactive micelles that are destined in targeting further complicated disease and growth factor propagation.These techniques are important in determining structure-symmetry and asymmetry leading to meso-spherical crystal-packing modes or to copolymer vesiculization.The main objective of this review is to highlight and elucidate the potential role of lipopeptides in promoting signals at surface/interface of micelles along with their functionalities in repairing cellular and nuclear damages.Moreover,state-of-the-art scientific knowledge is reviewed regarding bioconjugation and structuring charged-mono-layer and/or bi-layer phospholipidic membranes in adherent to signal-biopeptides using some advanced techniques such as ultra-sound probe based polydispersity of radioactive trace-elements assisted microdialysis as micro-separating techniques in between those miscible and immiscible compounds.
基金Science and Engineering Research Board(SERB)Govt.of India,New Delhi,under File No.SERB-DST-NPDF/2016/001409.
文摘Fusarium dry rot is considered to be the most critical soilborne and postharvest disease that damages potato tubers worldwide when they are stored for a long time.This study was performed to demonstrate the effect of crude extract,culture filtrate,and cell suspension obtained from the bacterium Bacillus subtilis Hussain T-AMU,on the net house and field.From oil-contaminated soil,through the serial dilution method,biosurfactant bacteria were isolated on nutrient agar medium.To isolate and screen the prospective biosurfactant strain,various biosurfactant screening methods were used.Standard protocols were carried out for morphological,molecular,and chemical characterization.The disease incidences were significantly decreased under net house and field conditions after treatment with biosurfactant extract(20%,70%),culture filtrate(23%,49%),and bacterial cell suspension(46%,27%),respectively.These results indicate a significant effect of B.subtilis HussainT-AMU against Fusarium oxysporum.The characterization of the partially purified extract by gas-chromatography indicated the existence of a high amount of methyl ester fatty acids.The quantitative analysis determined the presence of lipopeptide-surfactin,fengycin,and iturin in the biosurfactant extract.Scanning electron microscopy revealed that morphological variation was revealed in the structure of stomata size in leaves and in the mycelia of the pathogen that was investigated.This promising biocontrol agent can be a plausible option for further research and can also be used for the production of green biomolecules at an additional industrial level.
基金The work was supported by Tamil Nadu State Council for Science and Technology(TNSCST),Chennai,India(MS-004/TNSCST/SPS/AR/2010-2011)
文摘Objective:To characterize the pharmacological importance of biosurfactants isolated from halophilic Bacillus sp BS3.Methods:Halophilic Bacillus sp.BS3 was isolated from solar salt works,identified by 16S rRNA sequencing and was used for screening their biosurfactant production.Characters of the biosurfactant and their anticancer activity were analyzed and performed in mammary epithelial carcinoma cell at different concentrations.Results:The biosurfactant were characterized by TLC,FTIR and GC-MS analysis and identified as lipopeptide type.GC-MS analysis revealed that,the biosurfactant had various compounds including 13Docosenamide.(Z);Mannosamine,9- and N,N,N',N'-tetramethyl.Surprisingly the antiviral activity was found against shrimp white spot syndrome virus(WSSV) by suppressing the viral replication and significantly raised shrimp survival(P<0.01).Anticancer activity performed in the mammary epithelial carcinoma cell at different concentrations of biosurfactants,among the various concentrations of biosurfactants such as 0.000 25,0.002 5,0.025,0.25 and 2.5 μ g,the 0.25 μ g concentration suppressed the cells significantly(P<0.05) to 24.8%.Conclusions:Based on the findings,the present study concluded that,there is a possibility to develop eco-friendly antimicrobial and anticancer drugs from the extremophilic origin.
