The importance of controlled temperature during the four-days co-cultivation period was evaluated under the most physiologically relevant conditions for Agrobacterium tumefaciens-mediated transformation of tobacco (Ni...The importance of controlled temperature during the four-days co-cultivation period was evaluated under the most physiologically relevant conditions for Agrobacterium tumefaciens-mediated transformation of tobacco (Nicotiana tabacum L. cv. Xanthi (nn, Smith)) leaf disks. We compared the effect of temperatures ranging from 15°C, 18°C, 20°C, 22°C to 25°C on the stable expression of β-glucuronidase (GUS) activity of 14 days old hygromycin-selected leaf disks, and on the increase in the fresh weight yield of 28 days old kanamycin-selected calli. The highest average of GUS activity was obtained at 20°C among the five temperatures tested although the difference between the 18°C and 20°C treatment was not statistically significant. The GUS activity at 15°C was statistically lower than those at 18°C and 20°C. The GUS activity in 22°C treatment was an intermediate between the highest (18/20°C) and second highest averages (15°C), and was not statistically significantly different. The lowest average of GUS activity was observed at 25°C. The highest increase in the plate average of fresh weight yield was obtained at 20°C among the five temperature tested. The 20°C treatment was statistically significantly better than the 15°C and 18°C treatments. The 20°C co-cultivation treatment resulted in the higher FW yield than 22°C and 25°C even though the differences were not statistically significant. In conclusion, low co-cultivation temperature at 20°C resulted in the reproducible maximum increase in both the fresh weight yield and stable expression of GUS activity after transformation of tobacco leaf disks.展开更多
The management and recycling of plastic waste is a challenging global issue.Polyethylene terephthalate(PET),one of the most widely used synthetic plastics,can be hydrolyzed by a series of enzymes.However,upcycling the...The management and recycling of plastic waste is a challenging global issue.Polyethylene terephthalate(PET),one of the most widely used synthetic plastics,can be hydrolyzed by a series of enzymes.However,upcycling the resulting monomers is also a problem.In this study,we designed a co-cultivation system,in which PET degradation was coupled with polyhydroxybutyrate(PHB)production.First,PETase from Ideonalla sakaiensis was expressed in Yarrowia lipolytica Po1f with a signal peptide from lipase.The engineered PETase-producing Y.lipolytica was confirmed to hydrolyze bis(2-hydroxyethyl)terephthalate(BHET)and PET powder into the monomers terephthalate(TPA)and ethylene glycol(EG).Simultaneously,a TPA-degrading Pseudomonas stutzeri strain isolated from PET waste was transformed with a recombinant plasmid containing the phb CAB operon from Ralstonia eutropha,which encodes enzymes for the biosynthesis of PHB.The two co-cultivated engineered microbes could directly hydrolyze BHET to produce the bioplastic PHB in one fermentation step.During this process,5.16 g/L BHET was hydrolyzed in 12 h,and 3.66 wt%PHB(3.54 g/L cell dry weight)accumulated in 54 h.A total of 0.31g/L TPA was produced from the hydrolyzation of PET in 228 h.Although PHB could not be synthesized directly from PET because of the low hydrolyzing efficiency of PETase,this study provides a new strategy for the biodegradation and upcycling of PET waste by artificial microflora.展开更多
School of Information and Software Engineering at University of Electronic Science and Technology of China(abbreviated hereafter as "SISE") joined Excellent Engineer Education and Training Program launched b...School of Information and Software Engineering at University of Electronic Science and Technology of China(abbreviated hereafter as "SISE") joined Excellent Engineer Education and Training Program launched by Ministry of Education of China in 2011. This paper discussed nine models of school-enterprise cooperation practiced at SISE since 2011. The school-enterprise cooperation model effectively broadens the students' horizons and improves the students' practical ability and has been recognized by academic circles.展开更多
Zinc is an essential trace element required for bone remodelling process,but its role in such process remains to be elucidated.In particular,inconsistent results have been reported on the effect of Zn on osteoclastic ...Zinc is an essential trace element required for bone remodelling process,but its role in such process remains to be elucidated.In particular,inconsistent results have been reported on the effect of Zn on osteoclastic responses,and supplement of receptor activator of nuclear factor kappa-B ligand(RANKL)factors has been commonly adopted.Co-culture is a suitable approach to elucidating the role of Zn in bone remodelling process,by better imitating the cellular environment as the presence of osteoblasts plays critical role in modulating osteoclastic functions.In this study,zincsubstituted HA coatings have been deposited using a liquid precursor plasma spraying process at two different concentrations(1,2 wt.%).The effect of zinc substitution on osteoblastic and osteoclastic differentiation has been studied in vitro.In particular,a cultivation regime was designed to first induce osteoblastic differentiation of rat bone marrow stromal cells(BMSCs)for 14 days,and then induce osteoclastic differentiation of osteoclast-like precursor RAW 264.7 cells through the aid of the osteoblasts formed for additional 14 days,in the absence of the external addition of RANKL.The results showed that Zn substitution moderately promoted the BMSC differentiation into the osteoblasts and reduced the osteoclastic activity in early time(1 day co-culture).However,promotion of the osteoclastic activity were observed at later stages,as indicated by the significantly enhanced expressions of trap5b and IL-1(8-and 15-day co-culture)and moderate stimulation of the nucleus integration and formation of the multinucleated cells(14-day co-culture).Such stimulating effect of the osteoclastic activity was absent under mono-culture of RAW 264.7 cell,with simple RANKL supplementation.The results suggest that both the zinc and the presence of MSC/osteoblast play profound and highly interacted roles on osteoclast differentiation and activity,which is critical in modulating the bone remodelling process.展开更多
Algal phytoremediation represents a practical green solution for treating anaerobically digested piggery effluent(ADPE). The potential and viability of combining microalgae and macroalgae cultivation for the efficient...Algal phytoremediation represents a practical green solution for treating anaerobically digested piggery effluent(ADPE). The potential and viability of combining microalgae and macroalgae cultivation for the efficient treatment of ADPE were evaluated in this study.Bioprospecting the ability of different locally isolated macroalgae species illustrated the potential of Cladophora sp. to successfully grow and treat ADPE with up to 150 mg/L NH_4^+ with a biomass productivity of(0.13 ± 0.02) g/(L·day) and ammonium removal rate of(10.23 ± 0.18) mg/(L·day) NH_4^+. When grown by itself, the microalgae consortium used in this study consisting of Chlorella sp. and Scenedesmus sp. was found to grow and treat undiluted ADPE(up to 525 mg/L NH_4^+) with an average ammonium removal rate of 25 mg/(L·day) NH_4^+ and biomass productivity of(0.012 ± 0.0001) g/(L·day). Nevertheless, when combined together, despite the different cultivation systems(attached and non-attached) evaluated,microalgae and macroalgae were unable to co-exist together and treat ADPE as their respective growth were inversely related to each other due to direct competition for nutrients and available resources as well as the negative physical interaction between both algal groups.展开更多
文摘The importance of controlled temperature during the four-days co-cultivation period was evaluated under the most physiologically relevant conditions for Agrobacterium tumefaciens-mediated transformation of tobacco (Nicotiana tabacum L. cv. Xanthi (nn, Smith)) leaf disks. We compared the effect of temperatures ranging from 15°C, 18°C, 20°C, 22°C to 25°C on the stable expression of β-glucuronidase (GUS) activity of 14 days old hygromycin-selected leaf disks, and on the increase in the fresh weight yield of 28 days old kanamycin-selected calli. The highest average of GUS activity was obtained at 20°C among the five temperatures tested although the difference between the 18°C and 20°C treatment was not statistically significant. The GUS activity at 15°C was statistically lower than those at 18°C and 20°C. The GUS activity in 22°C treatment was an intermediate between the highest (18/20°C) and second highest averages (15°C), and was not statistically significantly different. The lowest average of GUS activity was observed at 25°C. The highest increase in the plate average of fresh weight yield was obtained at 20°C among the five temperature tested. The 20°C treatment was statistically significantly better than the 15°C and 18°C treatments. The 20°C co-cultivation treatment resulted in the higher FW yield than 22°C and 25°C even though the differences were not statistically significant. In conclusion, low co-cultivation temperature at 20°C resulted in the reproducible maximum increase in both the fresh weight yield and stable expression of GUS activity after transformation of tobacco leaf disks.
基金funding from the National Natural Science Foundation of China(grant numbers:Institute of Microbiology,Chi-nese Academy of Sciences:31961133016Beijing Institute of Technol-ogy:31961133015Shandong University:31961133014)and the Na-tional Key Research and Development Program of China(grant num-ber:2019YFA0706900)and was supported by European Union’s Hori-zon 2020 research and innovation programme under grant agreement No.870292(BIOICEP).
文摘The management and recycling of plastic waste is a challenging global issue.Polyethylene terephthalate(PET),one of the most widely used synthetic plastics,can be hydrolyzed by a series of enzymes.However,upcycling the resulting monomers is also a problem.In this study,we designed a co-cultivation system,in which PET degradation was coupled with polyhydroxybutyrate(PHB)production.First,PETase from Ideonalla sakaiensis was expressed in Yarrowia lipolytica Po1f with a signal peptide from lipase.The engineered PETase-producing Y.lipolytica was confirmed to hydrolyze bis(2-hydroxyethyl)terephthalate(BHET)and PET powder into the monomers terephthalate(TPA)and ethylene glycol(EG).Simultaneously,a TPA-degrading Pseudomonas stutzeri strain isolated from PET waste was transformed with a recombinant plasmid containing the phb CAB operon from Ralstonia eutropha,which encodes enzymes for the biosynthesis of PHB.The two co-cultivated engineered microbes could directly hydrolyze BHET to produce the bioplastic PHB in one fermentation step.During this process,5.16 g/L BHET was hydrolyzed in 12 h,and 3.66 wt%PHB(3.54 g/L cell dry weight)accumulated in 54 h.A total of 0.31g/L TPA was produced from the hydrolyzation of PET in 228 h.Although PHB could not be synthesized directly from PET because of the low hydrolyzing efficiency of PETase,this study provides a new strategy for the biodegradation and upcycling of PET waste by artificial microflora.
文摘School of Information and Software Engineering at University of Electronic Science and Technology of China(abbreviated hereafter as "SISE") joined Excellent Engineer Education and Training Program launched by Ministry of Education of China in 2011. This paper discussed nine models of school-enterprise cooperation practiced at SISE since 2011. The school-enterprise cooperation model effectively broadens the students' horizons and improves the students' practical ability and has been recognized by academic circles.
基金the Natural Science Foundation of China(No.31170922)National Basic Research Program of China(No.2012cb619103)+1 种基金the Research Fund for the Doctoral Program of Higher Education(No.20120181110058)Program for New Century Excellent Talents in University(NCET-12-0387).
文摘Zinc is an essential trace element required for bone remodelling process,but its role in such process remains to be elucidated.In particular,inconsistent results have been reported on the effect of Zn on osteoclastic responses,and supplement of receptor activator of nuclear factor kappa-B ligand(RANKL)factors has been commonly adopted.Co-culture is a suitable approach to elucidating the role of Zn in bone remodelling process,by better imitating the cellular environment as the presence of osteoblasts plays critical role in modulating osteoclastic functions.In this study,zincsubstituted HA coatings have been deposited using a liquid precursor plasma spraying process at two different concentrations(1,2 wt.%).The effect of zinc substitution on osteoblastic and osteoclastic differentiation has been studied in vitro.In particular,a cultivation regime was designed to first induce osteoblastic differentiation of rat bone marrow stromal cells(BMSCs)for 14 days,and then induce osteoclastic differentiation of osteoclast-like precursor RAW 264.7 cells through the aid of the osteoblasts formed for additional 14 days,in the absence of the external addition of RANKL.The results showed that Zn substitution moderately promoted the BMSC differentiation into the osteoblasts and reduced the osteoclastic activity in early time(1 day co-culture).However,promotion of the osteoclastic activity were observed at later stages,as indicated by the significantly enhanced expressions of trap5b and IL-1(8-and 15-day co-culture)and moderate stimulation of the nucleus integration and formation of the multinucleated cells(14-day co-culture).Such stimulating effect of the osteoclastic activity was absent under mono-culture of RAW 264.7 cell,with simple RANKL supplementation.The results suggest that both the zinc and the presence of MSC/osteoblast play profound and highly interacted roles on osteoclast differentiation and activity,which is critical in modulating the bone remodelling process.
基金supported by the Cooperative Research Centre for High Integrity Australian Pork(Pork CRC)through the grant(Pork CRC 4A-109)
文摘Algal phytoremediation represents a practical green solution for treating anaerobically digested piggery effluent(ADPE). The potential and viability of combining microalgae and macroalgae cultivation for the efficient treatment of ADPE were evaluated in this study.Bioprospecting the ability of different locally isolated macroalgae species illustrated the potential of Cladophora sp. to successfully grow and treat ADPE with up to 150 mg/L NH_4^+ with a biomass productivity of(0.13 ± 0.02) g/(L·day) and ammonium removal rate of(10.23 ± 0.18) mg/(L·day) NH_4^+. When grown by itself, the microalgae consortium used in this study consisting of Chlorella sp. and Scenedesmus sp. was found to grow and treat undiluted ADPE(up to 525 mg/L NH_4^+) with an average ammonium removal rate of 25 mg/(L·day) NH_4^+ and biomass productivity of(0.012 ± 0.0001) g/(L·day). Nevertheless, when combined together, despite the different cultivation systems(attached and non-attached) evaluated,microalgae and macroalgae were unable to co-exist together and treat ADPE as their respective growth were inversely related to each other due to direct competition for nutrients and available resources as well as the negative physical interaction between both algal groups.
