Moist heat sterilization is one of the most common sterilization methods in hospitals.Among all the ways of sterilization monitoring,biological monitoring is the most accurate one,which has become the focus of numerou...Moist heat sterilization is one of the most common sterilization methods in hospitals.Among all the ways of sterilization monitoring,biological monitoring is the most accurate one,which has become the focus of numerous studies in recent years.Bacillus stearothermophilus ATCC7953,as a kind of standard bacterial strain,receives much attention.Biological indicator(BI)able to read in shorter time is called as Rapid-Read biological indicator(RRBI).This article will introduce several characters of ATCC7953 including some simple parameters and spores germination.Additionally,the application of ATCC7953 in BI,especially RRBI,will also be covered.展开更多
Microbial synthesis of functional polymers has become increasingly important for industrial biotechnology. For the first time, it became possible to synthesize controllable composition of poly（3-hydroxyalkanoate） （...Microbial synthesis of functional polymers has become increasingly important for industrial biotechnology. For the first time, it became possible to synthesize controllable composition of poly（3-hydroxyalkanoate） （P3HA） consisting of 3-hydroxydodec- anoate （3HDD） and phenyl group on the side-chain when chromosome of Pseudomonas entomophila was edited to weaken its t-oxidation. Cultured in the presence of 5-phenylvaleric acid （PVA）, the edited P. entomophila produced only homopolymer poly（3-hydroxy-5-phenylvalerate） or P（3HPhV）. While copolyesters P（3HPhV-co-3HDD） of 3-hydroxy-5-phenylvalerate （3HPhV） and 3-hydroxydodecanoate （3HDD） were synthesized when the strain was grown on mixtures of PVA and dodecanoic acid （DDA）. Compositions of 3HPhV in P（3HPhV-co-3HDD） were controllable ranging from 3% to 32% depending on DDDA/PVA ratios. Nuclear magnetic resonance （NMR） spectra clearly indicated that the polymers were homopolymer of P（3HPhV） and random copolymers of 3HPhV and 3HDD. Their mechanical and thermal properties varied dramatically de- pending on the monomer ratios. Our results demonstrated the possibility to produce tailor-made, novel functional PHA using the chromosome edited P. entomophila.展开更多
文摘Moist heat sterilization is one of the most common sterilization methods in hospitals.Among all the ways of sterilization monitoring,biological monitoring is the most accurate one,which has become the focus of numerous studies in recent years.Bacillus stearothermophilus ATCC7953,as a kind of standard bacterial strain,receives much attention.Biological indicator(BI)able to read in shorter time is called as Rapid-Read biological indicator(RRBI).This article will introduce several characters of ATCC7953 including some simple parameters and spores germination.Additionally,the application of ATCC7953 in BI,especially RRBI,will also be covered.
基金supported by the National High Technology Research and Development Program of China(2012AA023102 to Liu Lei,Guo Kai and Wu Qiong)the National Basic Research Program of China(2012CB725201 to Chen GuoQiang and Chen JinChun,2012CB725204 to Guo Kai and Wu Qiong)National Natural Science Foundation of China(31270146 to Chen GuoQiang)
文摘Microbial synthesis of functional polymers has become increasingly important for industrial biotechnology. For the first time, it became possible to synthesize controllable composition of poly（3-hydroxyalkanoate） （P3HA） consisting of 3-hydroxydodec- anoate （3HDD） and phenyl group on the side-chain when chromosome of Pseudomonas entomophila was edited to weaken its t-oxidation. Cultured in the presence of 5-phenylvaleric acid （PVA）, the edited P. entomophila produced only homopolymer poly（3-hydroxy-5-phenylvalerate） or P（3HPhV）. While copolyesters P（3HPhV-co-3HDD） of 3-hydroxy-5-phenylvalerate （3HPhV） and 3-hydroxydodecanoate （3HDD） were synthesized when the strain was grown on mixtures of PVA and dodecanoic acid （DDA）. Compositions of 3HPhV in P（3HPhV-co-3HDD） were controllable ranging from 3% to 32% depending on DDDA/PVA ratios. Nuclear magnetic resonance （NMR） spectra clearly indicated that the polymers were homopolymer of P（3HPhV） and random copolymers of 3HPhV and 3HDD. Their mechanical and thermal properties varied dramatically de- pending on the monomer ratios. Our results demonstrated the possibility to produce tailor-made, novel functional PHA using the chromosome edited P. entomophila.
