In peanuts, a mechanism of resistance to fungal infection is reported on the synthesis of stilbene phytoalexins, which are antibiotic, low molecular weight metabolites. The phytoalexin-associated response of different...In peanuts, a mechanism of resistance to fungal infection is reported on the synthesis of stilbene phytoalexins, which are antibiotic, low molecular weight metabolites. The phytoalexin-associated response of different peanut varieties to the inoculation with A. flavus has not been investigated and might be useful for breed- ing resistant peanut cultivars. In this study, peanut varieties resistant or susceptible to aflatoxin accumulation caused by A. flavus were selected to compare the synthe- sis differences of the four main stilbenes （resveratrol, ε-viniferin, 6-viniferin and pterostilbene） and the activities of their resistant enzymes （PAL, POD, PPO）, and explore the relationship between stilbene synthesis and resistance to aflatoxin accu- mulation. The results indicated that the synthesis speed of stilbenes was related to the resistance to aflatoxin accumulation in peanuts seeds. The total content of the four stilbenes reached the highest value of 47.37 μg/g in the resistant cultivars （Qian huasheng 3） after inoculation by A. flavus （54 times of the control） on the 3nd day, while the total content of stilbenes in susceptible cultivars （Huayu 22） was 5.5 μg/g. The content of stilbenes and the activities of their resistant enzymes from the resistant cultivars were both higher than from the susceptible one. The four peanut varieties with relative higher stilbene contents and lower disease index and aflatoxin content were selected by using the stilbene content. Very significant negative corre- lation, with correlation coefficients （r） of -0.789, -0.851 and -0.850, was observed between the stilbene content with disease index, the content of aflatoxin B1 and the total content of aflatoxins, respectively. Therefore, the study suggested that the total content of stilbene compounds might serve as an important chemical index in peanut seeds after inoculation with A. flavus on the 3nd day, during screening and breeding of peanut varieties resistant to aflatoxin accumulation.展开更多
[Objective] The antifungal activity of the extracts from,Atractylodes macracephal Koidz and Pulsatilla chinensis Bunge Regel,against Botrytis cinerea and Alternaria solani were studied under the condition of laborator...[Objective] The antifungal activity of the extracts from,Atractylodes macracephal Koidz and Pulsatilla chinensis Bunge Regel,against Botrytis cinerea and Alternaria solani were studied under the condition of laboratory,in order to develop and utilize these two plants.[Method] The mycelium growth rate test was applied to measure the antifungal activities of extracts against fungi.[Result] the extracts of all the two plants showed strong antifungal activity against the target pathogenic fungi,especially the antifungal activity of the extract from Pulsatilla chinensis Bunge Regel was stronger and more stable.The inhibition rate to the mycelium growth of Botrytis cinerea was 80.25%.At the same concentration,the extract from Atractylodes macracephal Koidz showed little inhibition to Botrytis cinerea and Alternaria solani.The petrolelum ether extract of Atractylodes macracephal Koidz showed stronger antifungal activities and the EC50 was 5.31 mg/ml,and the n-butanol extract of Pulsatilla chinensis Bunge Regel showed stronger antifungal activities and the EC50 was 2.93 mg/ml.[Conclusion] The extracts from Pulsatilla chinensis Bunge Regel showed the stronger antifungal activity against Botrytis cinerea and Alternaria solani.展开更多
Aim To synthesize 4″-carbamate derivatives of erythromycin and test their antibacterial activities in vitro. Methods New erythromycin antibacterial agents containing 4″-carbamate group were designed and synthesized ...Aim To synthesize 4″-carbamate derivatives of erythromycin and test their antibacterial activities in vitro. Methods New erythromycin antibacterial agents containing 4″-carbamate group were designed and synthesized from azithromycin via protection, aminoformylation, amination and deprotection. Their antibacterial activities against Staphylococcus aureus strains were tested. Results Nine compounds were synthesized. Their structures were confirmed by MS, IR, ~ 1 H NMR and ~ 13 C NMR, and the synthetic conditi...展开更多
Gray mold caused by Botrytis cinerea is a major disease of greenhouse cucumbers and its control is largely dependent on the succinate dehydrogenase inhibitor boscalid.In this study,gray mold-infected cucumbers were co...Gray mold caused by Botrytis cinerea is a major disease of greenhouse cucumbers and its control is largely dependent on the succinate dehydrogenase inhibitor boscalid.In this study,gray mold-infected cucumbers were collected from greenhouses located in 11 towns in which boscalid had been used,and 163 B.cinerea strains were isolated by single-spore method.The EC50 value effective concentration that could inhibit conidia germination by 50%compared with the control for sensitive isolates ranged from 0.045μg/mL to 50.148μg/mL in the assays.Additionally,101 isolates were resistant to boscalid,and the resistance frequency ranged from 33.33%to 86.67%in these towns.Most of the resistant isolates showed a low or moderately resistant phenotype,with the resistance frequency of moderately resistant isolates being as high as 80%.The SdhB gene harbored a single mutation corresponding to His272.The fitness evaluation showed that the hyphal growth,sporulation,germinability and pathogenicity were different among the resistant and sensitive isolates.The results suggested that dual resistance to boscalid in B.cinerea populations could result in failure to control gray mold.展开更多
The water extract of dry mycelium ofPenicillium chrysogenum （DME） was used to induce resistance in Virginia tobacco plants against Phtophthora parasitica var. nicotianae. Results showed that the efficacy of DME in c...The water extract of dry mycelium ofPenicillium chrysogenum （DME） was used to induce resistance in Virginia tobacco plants against Phtophthora parasitica var. nicotianae. Results showed that the efficacy of DME in controlling black shank disease depended on both DME solution concentration and its＇ treatment methodology. Soil application of 1.5-5% DME 72 hr before inoculation with Phtophthora parasitica vat. nicotianae provided highly significant protection against black shank, relative to the control without DME treatment. Optimized tobacco plant treatment with 2.5% DME significantly increased peroxidase （POD） and polyphenol oxidase （PPO） activity levels in the upper leaf sections of the tobacco plants. DME had no direct antifungal activity on the growth of Phtophthora parasitica var. nicotianae in vitro, suggesting that disease control with DME treatment resulted from the induced propagation of natural defense mechanisms in the tobacco plants.展开更多
There is a method for investigating the transformation of resistance gene of carbendazim into Trichoderma harzianum. In order to introduce the resistance to benzimidazole fungicide into bio-control microorganism Trich...There is a method for investigating the transformation of resistance gene of carbendazim into Trichoderma harzianum. In order to introduce the resistance to benzimidazole fungicide into bio-control microorganism Trichoderma harzianum was transformed with the resistance gene. In this study, we investigate resistance level and calculate EC 50 (effective concentration of carbendazim that can survive 50% of Trichoderma harzianum in that concentration) and stability of the resistance for the transformant isolate of Trichoderma harzianum. Results show the transformants can growth on the medium containing more than 1 000 μg/ml carbendazim and the resistance is stabled after 10 times transfer on non-selective medium and have EC 50 average about, 1 200 μg/ml.展开更多
SalNa （sodium salinomycin） reacts with divalent transition metal ions of Co（II）, Ni（II）, Cu（II） and Zn（II） to produce novel compounds characterized by various spectroscopic methods. The interaction of metal ...SalNa （sodium salinomycin） reacts with divalent transition metal ions of Co（II）, Ni（II）, Cu（II） and Zn（II） to produce novel compounds characterized by various spectroscopic methods. The interaction of metal （II） ions with SalNa results in the formation of mononuclear complexes of a general composition of [M（Sal）2·（H2O）2] nH2O （n = 0 or 2） where the divalent cations replace Na~ ions from the cavity of initial compound. The new compounds （disalinomycinates） possess an enhanced antibacterial activity against Gram-positive microorganisms as compared to both SalNa and SalH （salinomycinic acid）, respectively. The metal （II） complexes manifest strong concentration dependent cytotoxic effect in experiments using human leukemia cell lines. The complexes of Co0I） and Cu（lI） proved to exert superior activity as compared to the Ni（II） and Zn（II） analogues and are much more cytotoxic than SalNa and SalH. Further studies should be conducted to determine the therapeutic indexes of the new compounds.展开更多
In this study, three hymexazol-linked chitosan derivatives （HML-CS） were synthesized and their structures confirmed by Fourier transform infrared and elemental analysis. Linkage ratios were measured by high performa...In this study, three hymexazol-linked chitosan derivatives （HML-CS） were synthesized and their structures confirmed by Fourier transform infrared and elemental analysis. Linkage ratios were measured by high performance liquid chromatography. The derivatives＇ antifungal activity against the plant pathogenic fimgi Rhizoctonia solani CGMCC 3.28 and Gibberella zeae CGMCC 3.42 were investigated at concentrations of 100, 200, and 400 mg/L. These HML-CS derivatives exhibited stronger antifungal activity than CS alone. HML-CS-1 showed the best antifizngal activity against G. zeae, whose antifimgal index was 65.9% at 400 mg/L, and also showed the best antifungal activity against R. solani, whose antifimgal index was 52.7% at 400 mg/L. This conjugation of CS and HML suggested the presence of synergistic effects between the moieties and indicated that these derivatives possessed great potential as novel fungicides and require further research for the development of applications in crop protection.展开更多
Synechococcus sp.CC9311 is a marine cyanobacterium characterized by type IV chromatic acclimation(CA).A genetic transformation system was developed as a first step to elucidate the molecular mechanism of CA.The result...Synechococcus sp.CC9311 is a marine cyanobacterium characterized by type IV chromatic acclimation(CA).A genetic transformation system was developed as a first step to elucidate the molecular mechanism of CA.The results show that Synechococcus sp.CC9311 cells were sensitive to four commonly used antibiotics:ampicillin,kanamycin,spectinomycin,and chloramphenicol.An integrative plasmid to disrupt the putative phycoerythrin lyase gene mpeV,using a kanamycin resistance gene as selectable marker,was constructed by recombinant polymerase chain reaction.The plasmid was then transformed into Synechococcus sp.CC9311 via electroporation.High transformation efficiency was achieved at a field strength of 2 kV/cm.DNA analysis showed that mpeV was fully disrupted following challenge of the transformants with a high concentration of kanamycin.In addition,the transformants that displayed poor growth on agar SN medium could be successfully plated on agarose SN medium.展开更多
Increasing the self-resistance levels of Streptomyces is an effective strategy to improve the production of antibiotics.To increase the oxytetracycline(OTC) production in Streptomyces rimosus,we investigated the coope...Increasing the self-resistance levels of Streptomyces is an effective strategy to improve the production of antibiotics.To increase the oxytetracycline(OTC) production in Streptomyces rimosus,we investigated the cooperative effect of three co-overexpressing OTC resistance genes:one gene encodes a ribosomal protection protein(otrA) and the other two express efflux proteins(otrB and otrC).Results indicated that combinational overexpression of otrA,otrB,and otrC(MKABC) exerted a synergetic effect.OTC production increased by 179%in the recombinant strain compared with that of the wild-type strain M4018.The resistance level to OTC was increased by approximately two-fold relative to the parental strain,thereby indicating that applying the cooperative effect of self-resistance genes is useful to improve OTC production.Furthermore,the previously identified cluster-situated activator OtcR was overexpressed in MKABC in constructing the recombinant strain MKRABC;such strain can produce OTC of approximately7.49 g L^((-1)),which represents an increase of 19%in comparison with that of the OtcR-overexpressing strain alone.Our work showed that the cooperative overexpression of self-resistance genes is a promising strategy to enhance the antibiotics production in Streptomyces.展开更多
Bacterial infections are grave threats to human health,particularly those caused by the most common Grampositive bacteria.The massive administration of broad-spectrum antibiotics to treat various bacterial infections ...Bacterial infections are grave threats to human health,particularly those caused by the most common Grampositive bacteria.The massive administration of broad-spectrum antibiotics to treat various bacterial infections has led to the evolution and spread of drug resistance.As a universal antimicrobial technique unapt to induce drug resistance,photothermal therapy(PTT)is attracting extensive attention in recent years.However,its unspecific killing capability and side effects towards adjacent mammalian cells severely impede the practical applications.Herein,we proposed a metabolic engineering strategy to selectively inactivate Gram-positive bacteria by PTT.A bioorthogonal photothermal agent was prepared by the conjugation of IR-780 iodide and dibenzocyclooctyne(IR780-DBCO).Upon pre-metabolizing with 3-azido-D-alanine,Gram-positive bacteria rather than Gramnegative ones,such as Staphylococcus aureus and vancomycinresistant Enterococcus faecalis(VRE),could be specifically tied up by the explosive IR780-DBCO via copper-free click chemistry.Thereafter,they spontaneously detonated under 15 min near-infrared light irradiation and inactivated nearly 100% Gram-positive bacteria in vitro.Moreover,superbug VRE-induced infection was significantly inhibited by this approach in a mouse skin wound model.This metabolic labelling-based photothermal ablation strategy specific to Gram-positive microbes would stimulate the development of precise antibacterial candidates for preclinical applications.展开更多
基金Supported by Natural Science Foundation of Hainan Province(809034)National Nonprofit Institute Research Grant of CATAS-TCGRI(1630032012025)~~
文摘In peanuts, a mechanism of resistance to fungal infection is reported on the synthesis of stilbene phytoalexins, which are antibiotic, low molecular weight metabolites. The phytoalexin-associated response of different peanut varieties to the inoculation with A. flavus has not been investigated and might be useful for breed- ing resistant peanut cultivars. In this study, peanut varieties resistant or susceptible to aflatoxin accumulation caused by A. flavus were selected to compare the synthe- sis differences of the four main stilbenes （resveratrol, ε-viniferin, 6-viniferin and pterostilbene） and the activities of their resistant enzymes （PAL, POD, PPO）, and explore the relationship between stilbene synthesis and resistance to aflatoxin accu- mulation. The results indicated that the synthesis speed of stilbenes was related to the resistance to aflatoxin accumulation in peanuts seeds. The total content of the four stilbenes reached the highest value of 47.37 μg/g in the resistant cultivars （Qian huasheng 3） after inoculation by A. flavus （54 times of the control） on the 3nd day, while the total content of stilbenes in susceptible cultivars （Huayu 22） was 5.5 μg/g. The content of stilbenes and the activities of their resistant enzymes from the resistant cultivars were both higher than from the susceptible one. The four peanut varieties with relative higher stilbene contents and lower disease index and aflatoxin content were selected by using the stilbene content. Very significant negative corre- lation, with correlation coefficients （r） of -0.789, -0.851 and -0.850, was observed between the stilbene content with disease index, the content of aflatoxin B1 and the total content of aflatoxins, respectively. Therefore, the study suggested that the total content of stilbene compounds might serve as an important chemical index in peanut seeds after inoculation with A. flavus on the 3nd day, during screening and breeding of peanut varieties resistant to aflatoxin accumulation.
基金Supported by Talent Introduction Grantin Anhui Science and Technology University(ZRC2007102)Outstanding Young Talets Project of Anhui Provincal Universities(2009SQRZ11)~~
文摘[Objective] The antifungal activity of the extracts from,Atractylodes macracephal Koidz and Pulsatilla chinensis Bunge Regel,against Botrytis cinerea and Alternaria solani were studied under the condition of laboratory,in order to develop and utilize these two plants.[Method] The mycelium growth rate test was applied to measure the antifungal activities of extracts against fungi.[Result] the extracts of all the two plants showed strong antifungal activity against the target pathogenic fungi,especially the antifungal activity of the extract from Pulsatilla chinensis Bunge Regel was stronger and more stable.The inhibition rate to the mycelium growth of Botrytis cinerea was 80.25%.At the same concentration,the extract from Atractylodes macracephal Koidz showed little inhibition to Botrytis cinerea and Alternaria solani.The petrolelum ether extract of Atractylodes macracephal Koidz showed stronger antifungal activities and the EC50 was 5.31 mg/ml,and the n-butanol extract of Pulsatilla chinensis Bunge Regel showed stronger antifungal activities and the EC50 was 2.93 mg/ml.[Conclusion] The extracts from Pulsatilla chinensis Bunge Regel showed the stronger antifungal activity against Botrytis cinerea and Alternaria solani.
基金The Project Sponsored by the Foundation for Doctors, Jinan University, No.B0511
文摘Aim To synthesize 4″-carbamate derivatives of erythromycin and test their antibacterial activities in vitro. Methods New erythromycin antibacterial agents containing 4″-carbamate group were designed and synthesized from azithromycin via protection, aminoformylation, amination and deprotection. Their antibacterial activities against Staphylococcus aureus strains were tested. Results Nine compounds were synthesized. Their structures were confirmed by MS, IR, ~ 1 H NMR and ~ 13 C NMR, and the synthetic conditi...
基金Supported by the National Natural Science Foundation of China(31501665)the Application Program of Yuncheng University(CY2018016)the Doctoral Fund of Yuncheng University(YQ-2018012) and Subject Program of Yuncheng University(XK-2018006)~~
文摘Gray mold caused by Botrytis cinerea is a major disease of greenhouse cucumbers and its control is largely dependent on the succinate dehydrogenase inhibitor boscalid.In this study,gray mold-infected cucumbers were collected from greenhouses located in 11 towns in which boscalid had been used,and 163 B.cinerea strains were isolated by single-spore method.The EC50 value effective concentration that could inhibit conidia germination by 50%compared with the control for sensitive isolates ranged from 0.045μg/mL to 50.148μg/mL in the assays.Additionally,101 isolates were resistant to boscalid,and the resistance frequency ranged from 33.33%to 86.67%in these towns.Most of the resistant isolates showed a low or moderately resistant phenotype,with the resistance frequency of moderately resistant isolates being as high as 80%.The SdhB gene harbored a single mutation corresponding to His272.The fitness evaluation showed that the hyphal growth,sporulation,germinability and pathogenicity were different among the resistant and sensitive isolates.The results suggested that dual resistance to boscalid in B.cinerea populations could result in failure to control gray mold.
文摘The water extract of dry mycelium ofPenicillium chrysogenum （DME） was used to induce resistance in Virginia tobacco plants against Phtophthora parasitica var. nicotianae. Results showed that the efficacy of DME in controlling black shank disease depended on both DME solution concentration and its＇ treatment methodology. Soil application of 1.5-5% DME 72 hr before inoculation with Phtophthora parasitica vat. nicotianae provided highly significant protection against black shank, relative to the control without DME treatment. Optimized tobacco plant treatment with 2.5% DME significantly increased peroxidase （POD） and polyphenol oxidase （PPO） activity levels in the upper leaf sections of the tobacco plants. DME had no direct antifungal activity on the growth of Phtophthora parasitica var. nicotianae in vitro, suggesting that disease control with DME treatment resulted from the induced propagation of natural defense mechanisms in the tobacco plants.
文摘There is a method for investigating the transformation of resistance gene of carbendazim into Trichoderma harzianum. In order to introduce the resistance to benzimidazole fungicide into bio-control microorganism Trichoderma harzianum was transformed with the resistance gene. In this study, we investigate resistance level and calculate EC 50 (effective concentration of carbendazim that can survive 50% of Trichoderma harzianum in that concentration) and stability of the resistance for the transformant isolate of Trichoderma harzianum. Results show the transformants can growth on the medium containing more than 1 000 μg/ml carbendazim and the resistance is stabled after 10 times transfer on non-selective medium and have EC 50 average about, 1 200 μg/ml.
文摘SalNa （sodium salinomycin） reacts with divalent transition metal ions of Co（II）, Ni（II）, Cu（II） and Zn（II） to produce novel compounds characterized by various spectroscopic methods. The interaction of metal （II） ions with SalNa results in the formation of mononuclear complexes of a general composition of [M（Sal）2·（H2O）2] nH2O （n = 0 or 2） where the divalent cations replace Na~ ions from the cavity of initial compound. The new compounds （disalinomycinates） possess an enhanced antibacterial activity against Gram-positive microorganisms as compared to both SalNa and SalH （salinomycinic acid）, respectively. The metal （II） complexes manifest strong concentration dependent cytotoxic effect in experiments using human leukemia cell lines. The complexes of Co0I） and Cu（lI） proved to exert superior activity as compared to the Ni（II） and Zn（II） analogues and are much more cytotoxic than SalNa and SalH. Further studies should be conducted to determine the therapeutic indexes of the new compounds.
基金Supported by the National Natural Science Foundation of China(No.41306071)the Public Science and Technology Research Funds Projects of Ocean(No.201305016-2)the Science and Technology Development Program of Shandong Province(No.2012GHY11530)
文摘In this study, three hymexazol-linked chitosan derivatives （HML-CS） were synthesized and their structures confirmed by Fourier transform infrared and elemental analysis. Linkage ratios were measured by high performance liquid chromatography. The derivatives＇ antifungal activity against the plant pathogenic fimgi Rhizoctonia solani CGMCC 3.28 and Gibberella zeae CGMCC 3.42 were investigated at concentrations of 100, 200, and 400 mg/L. These HML-CS derivatives exhibited stronger antifungal activity than CS alone. HML-CS-1 showed the best antifizngal activity against G. zeae, whose antifimgal index was 65.9% at 400 mg/L, and also showed the best antifungal activity against R. solani, whose antifimgal index was 52.7% at 400 mg/L. This conjugation of CS and HML suggested the presence of synergistic effects between the moieties and indicated that these derivatives possessed great potential as novel fungicides and require further research for the development of applications in crop protection.
基金Supported by the Key Innovation Project of Institute of Oceanology,Chinese Academy of Sciences(No.2009-2)the Natural Science Foundation of Shandong Province(No.2009ZRB02542)+2 种基金the Foundation of Key Laboratory of Marine Bioactive Substance and Modern Analytical Techniques,SOA(No.MBSMAT-2010-03)the National Natural Science Foundation of China(No.41276164)the Natural Science Foundation of Jiangsu Province(No.BK2012650)
文摘Synechococcus sp.CC9311 is a marine cyanobacterium characterized by type IV chromatic acclimation(CA).A genetic transformation system was developed as a first step to elucidate the molecular mechanism of CA.The results show that Synechococcus sp.CC9311 cells were sensitive to four commonly used antibiotics:ampicillin,kanamycin,spectinomycin,and chloramphenicol.An integrative plasmid to disrupt the putative phycoerythrin lyase gene mpeV,using a kanamycin resistance gene as selectable marker,was constructed by recombinant polymerase chain reaction.The plasmid was then transformed into Synechococcus sp.CC9311 via electroporation.High transformation efficiency was achieved at a field strength of 2 kV/cm.DNA analysis showed that mpeV was fully disrupted following challenge of the transformants with a high concentration of kanamycin.In addition,the transformants that displayed poor growth on agar SN medium could be successfully plated on agarose SN medium.
基金supported by funding from Shengxue Dacheng Pharmaceutical Co.,Ltd,National Natural Science Foundation of China(31400034 and 31570031)the Ministry of Science and Technology of China(2013CB734001)
文摘Increasing the self-resistance levels of Streptomyces is an effective strategy to improve the production of antibiotics.To increase the oxytetracycline(OTC) production in Streptomyces rimosus,we investigated the cooperative effect of three co-overexpressing OTC resistance genes:one gene encodes a ribosomal protection protein(otrA) and the other two express efflux proteins(otrB and otrC).Results indicated that combinational overexpression of otrA,otrB,and otrC(MKABC) exerted a synergetic effect.OTC production increased by 179%in the recombinant strain compared with that of the wild-type strain M4018.The resistance level to OTC was increased by approximately two-fold relative to the parental strain,thereby indicating that applying the cooperative effect of self-resistance genes is useful to improve OTC production.Furthermore,the previously identified cluster-situated activator OtcR was overexpressed in MKABC in constructing the recombinant strain MKRABC;such strain can produce OTC of approximately7.49 g L^((-1)),which represents an increase of 19%in comparison with that of the OtcR-overexpressing strain alone.Our work showed that the cooperative overexpression of self-resistance genes is a promising strategy to enhance the antibiotics production in Streptomyces.
基金supported by the National Natural Science Foundation of China(52003222 and 21875189)Ningbo Natural Science Foundation(202003N4064)+2 种基金the Natural Science Foundation of Chongqing(cstc2020jcyj-msxmX0752)the Joint Research Funds of Department of Science&Technology of Shaanxi Province and Northwestern Polytechnical University(2020GXLH-Z-013)the Fundamental Research Funds for the Central Universities.
文摘Bacterial infections are grave threats to human health,particularly those caused by the most common Grampositive bacteria.The massive administration of broad-spectrum antibiotics to treat various bacterial infections has led to the evolution and spread of drug resistance.As a universal antimicrobial technique unapt to induce drug resistance,photothermal therapy(PTT)is attracting extensive attention in recent years.However,its unspecific killing capability and side effects towards adjacent mammalian cells severely impede the practical applications.Herein,we proposed a metabolic engineering strategy to selectively inactivate Gram-positive bacteria by PTT.A bioorthogonal photothermal agent was prepared by the conjugation of IR-780 iodide and dibenzocyclooctyne(IR780-DBCO).Upon pre-metabolizing with 3-azido-D-alanine,Gram-positive bacteria rather than Gramnegative ones,such as Staphylococcus aureus and vancomycinresistant Enterococcus faecalis(VRE),could be specifically tied up by the explosive IR780-DBCO via copper-free click chemistry.Thereafter,they spontaneously detonated under 15 min near-infrared light irradiation and inactivated nearly 100% Gram-positive bacteria in vitro.Moreover,superbug VRE-induced infection was significantly inhibited by this approach in a mouse skin wound model.This metabolic labelling-based photothermal ablation strategy specific to Gram-positive microbes would stimulate the development of precise antibacterial candidates for preclinical applications.
