Objective This study aimed to investigate the regulation of histone-like nucleoid structuring protein(H-NS)on biofilm formation and cyclic diguanylate(c-di-GMP)synthesis in Vibrio parahaemolyticus RIMD2210633.Methods ...Objective This study aimed to investigate the regulation of histone-like nucleoid structuring protein(H-NS)on biofilm formation and cyclic diguanylate(c-di-GMP)synthesis in Vibrio parahaemolyticus RIMD2210633.Methods Regulatory mechanisms were analyzed by the combined utilization of crystal violet staining,quantification of c-di-GMP,quantitative real-time polymerase chain reaction,LacZ fusion,and electrophoretic-mobility shift assay.Results The deletion of hns enhanced the biofilm formation and intracellular c-di-GMP levels in V.parahaemolyticus RIMD2210633.H-NS can bind the upstream promoter-proximal DNA regions of scrA,scrG,VP0117,VPA0198,VPA1176,VP0699,and VP2979 to repress their transcription.These genes encode a group of proteins with GGDEF and/or EAL domains associated with c-di-GMP metabolism.Conclusion One of the mechanisms by which H-NS represses the biofilm formation by V.parahaemolyticus RIMD2210633 may be via repression of the production of intracellular c-di-GMP.展开更多
[Objectives]To amplify the h-ns gene of Vibrio alginolyticus and analyze it by bioinformatics.[Methods]According to the h-ns gene sequence of V.alginolyticus HY9901,a pair of specific primers were designed and amplifi...[Objectives]To amplify the h-ns gene of Vibrio alginolyticus and analyze it by bioinformatics.[Methods]According to the h-ns gene sequence of V.alginolyticus HY9901,a pair of specific primers were designed and amplified by PCR.[Results]The h-ns gene was 408 bp in length and 135 amino acids were encoded.The predicted theoretical protein molecular weight was about 14.98 kD,and the isoelectric point was 4.99.Protein subcellular localization,SignalP 5.0,TMHMM Server 2.0 and SoftBerry-Psite predictions showed that H-NS was located outside the cell membrane,and the protein was unstable and hydrophobic.There was no signal peptide cleavage site,no transmembrane region and no KEGG metabolic pathway.The amino acid sequence contained three phosphorylation sites,one N-terminal myristoylation site and three microsomal C-terminal target signal sites.Using MEGA 5.0,H-NS phylogenetic tree was constructed by ortho-connection method.The results showed that H-NS of V.alginolyticus was closer to H-NS of Vibrio diabolicus.Using SWISS-MODEL,the three-dimensional structure model of H-NS subunit was simulated,which was similar to the crystal structure of Salmonella typhimurium H-NS1-83.[Conclusions]This study lays a foundation for exploring the regulation mechanism of V.alginolyticus H-NS protein on bacterial virulence in the future.展开更多
目的:建立一种利用SYBR Green I荧光PCR反应快速、准确、便捷检测副溶血性弧菌的方法。方法:根据副溶血性弧菌的H-NS基因的保守区域设计引物,利用副溶血性弧菌的标准菌株以及12株其他种属的常见致病菌对引物的特异性和灵敏度进行评价。...目的:建立一种利用SYBR Green I荧光PCR反应快速、准确、便捷检测副溶血性弧菌的方法。方法:根据副溶血性弧菌的H-NS基因的保守区域设计引物,利用副溶血性弧菌的标准菌株以及12株其他种属的常见致病菌对引物的特异性和灵敏度进行评价。基于该基因利用SYBR Green I荧光PCR检测方法建立标准曲线,确定该检测方法的灵敏度。对用不同浓度的菌液污染的灭菌过的蚬子样品进行检测,确定该方法的的可行性。最后用该方法检测30份蚬子样品,并与国标GB4789.7-2013检测结果进行比较。结果:用H-NS基因作为靶基因检测副溶血性弧菌的SYBR Green I荧光PCR检测方法,建立的标准曲线的相关系数为0.998,检测灵敏度为7.3×10 CFU/m L。人工污染蚬子的检出限为6.7×102CFU/m L。对蚬子样品的检测结果为30份样品中有4份含有副溶血性弧菌,与国家标准方法 (GB4789.7-2013)的检测结果具有一致性。结论:表明该方法可以用于副溶血性弧菌的快速检测。展开更多
The thermal behavior of the complex Pr[(C5H8NS2)3(C12H8N2)] in a dry nitrogen flow was examined by TG-DTG analysis. The TG-DTG investigations indicated that Pr[(C5H8NS2)3-(C12H8N2)] was decomposed into Pr2S3 and depos...The thermal behavior of the complex Pr[(C5H8NS2)3(C12H8N2)] in a dry nitrogen flow was examined by TG-DTG analysis. The TG-DTG investigations indicated that Pr[(C5H8NS2)3-(C12H8N2)] was decomposed into Pr2S3 and deposited carbon in one step where Pr2S3 predominated in the final products. The results of non-isothermal kinetic calculations showed that the decomposition stage was the random nucleation and subsequent growth mechanism (n = 2/3), the corresponding apparent activation energy ?was 115.89 kJ·mol-1 and the pre-expo-nential constant ln[A/s] was 7.8697. The empirical kinetics model equation was proposed as/(α) =3/2(1-α)[-ln(1-α)]1/3.The X-ray powder diffraction patterns of the thermal decomposition products at 800℃under N2 atmosphere show that the product can be indexed to the cubic Pr2S3 phase. The transmission electron microscopy (TEM) of the final product reveals the particle appearance of a diameter within 40 nm. The experimental results show that the praseodymium sulfide nanocrystal can be prepared from thermal decomposition of Pr[(C5H8NS2)3(C12H8N2)].展开更多
The reaction of[CpMo(CO)_2]_2 with 8,8'-diquinolyl disulphide C_9H_6NSSNC_9H_6 resulted in the cleavage of Mo≡Mo triple bond to give a new nononuclear complex CpMo(CO)_2(N,S-C_9H_6NS)which was refluxed with PPh_3...The reaction of[CpMo(CO)_2]_2 with 8,8'-diquinolyl disulphide C_9H_6NSSNC_9H_6 resulted in the cleavage of Mo≡Mo triple bond to give a new nononuclear complex CpMo(CO)_2(N,S-C_9H_6NS)which was refluxed with PPh_3 in THF to form the title complex.The crystal structure of the title complex was determined by X-ray diffraction.展开更多
The non-isothermal decomposition reaction of Nd[(C_5H_ 10NS_2)_3(C_ 12H_8N_2)] were carried out by means of TG-DTG and the thermal decomposition mechanism, and the associated kinetics was investigated. The kinetic par...The non-isothermal decomposition reaction of Nd[(C_5H_ 10NS_2)_3(C_ 12H_8N_2)] were carried out by means of TG-DTG and the thermal decomposition mechanism, and the associated kinetics was investigated. The kinetic parameters are obtained from an analysis of the TG-DTG curves at different heating rate by integral and differential methods. The most probable kinetic model function of the decomposition reaction is Maple Power of n=3/2, f(α)=2/3α -1/2 and the apparent activation energy E is 116.67 kJ·mol -1 and the pre-exponential factor lg[A/s -1] is 7.6891.展开更多
基金supported by grants from the National Natural Science Foundation of China[Grant No.82072239]。
文摘Objective This study aimed to investigate the regulation of histone-like nucleoid structuring protein(H-NS)on biofilm formation and cyclic diguanylate(c-di-GMP)synthesis in Vibrio parahaemolyticus RIMD2210633.Methods Regulatory mechanisms were analyzed by the combined utilization of crystal violet staining,quantification of c-di-GMP,quantitative real-time polymerase chain reaction,LacZ fusion,and electrophoretic-mobility shift assay.Results The deletion of hns enhanced the biofilm formation and intracellular c-di-GMP levels in V.parahaemolyticus RIMD2210633.H-NS can bind the upstream promoter-proximal DNA regions of scrA,scrG,VP0117,VPA0198,VPA1176,VP0699,and VP2979 to repress their transcription.These genes encode a group of proteins with GGDEF and/or EAL domains associated with c-di-GMP metabolism.Conclusion One of the mechanisms by which H-NS represses the biofilm formation by V.parahaemolyticus RIMD2210633 may be via repression of the production of intracellular c-di-GMP.
基金Supported by Outstanding Graduate Entering Laboratory Project of College of Fisheries,Guangdong Ocean UniversityNational Natural Science Foundation of China(32073015)+2 种基金Natural Science Foundation of Guangdong Province(2021A1515011078)Undergraduate Innovation and Entrepreneurship Training Program of Guangdong Ocean University(CXXL2022005)Undergraduate Innovation Team of Guangdong Ocean University(CCTD201802).
文摘[Objectives]To amplify the h-ns gene of Vibrio alginolyticus and analyze it by bioinformatics.[Methods]According to the h-ns gene sequence of V.alginolyticus HY9901,a pair of specific primers were designed and amplified by PCR.[Results]The h-ns gene was 408 bp in length and 135 amino acids were encoded.The predicted theoretical protein molecular weight was about 14.98 kD,and the isoelectric point was 4.99.Protein subcellular localization,SignalP 5.0,TMHMM Server 2.0 and SoftBerry-Psite predictions showed that H-NS was located outside the cell membrane,and the protein was unstable and hydrophobic.There was no signal peptide cleavage site,no transmembrane region and no KEGG metabolic pathway.The amino acid sequence contained three phosphorylation sites,one N-terminal myristoylation site and three microsomal C-terminal target signal sites.Using MEGA 5.0,H-NS phylogenetic tree was constructed by ortho-connection method.The results showed that H-NS of V.alginolyticus was closer to H-NS of Vibrio diabolicus.Using SWISS-MODEL,the three-dimensional structure model of H-NS subunit was simulated,which was similar to the crystal structure of Salmonella typhimurium H-NS1-83.[Conclusions]This study lays a foundation for exploring the regulation mechanism of V.alginolyticus H-NS protein on bacterial virulence in the future.
文摘目的:建立一种利用SYBR Green I荧光PCR反应快速、准确、便捷检测副溶血性弧菌的方法。方法:根据副溶血性弧菌的H-NS基因的保守区域设计引物,利用副溶血性弧菌的标准菌株以及12株其他种属的常见致病菌对引物的特异性和灵敏度进行评价。基于该基因利用SYBR Green I荧光PCR检测方法建立标准曲线,确定该检测方法的灵敏度。对用不同浓度的菌液污染的灭菌过的蚬子样品进行检测,确定该方法的的可行性。最后用该方法检测30份蚬子样品,并与国标GB4789.7-2013检测结果进行比较。结果:用H-NS基因作为靶基因检测副溶血性弧菌的SYBR Green I荧光PCR检测方法,建立的标准曲线的相关系数为0.998,检测灵敏度为7.3×10 CFU/m L。人工污染蚬子的检出限为6.7×102CFU/m L。对蚬子样品的检测结果为30份样品中有4份含有副溶血性弧菌,与国家标准方法 (GB4789.7-2013)的检测结果具有一致性。结论:表明该方法可以用于副溶血性弧菌的快速检测。
基金supported by the National Natural Science Foundation of China(Grant No.20171036)Education Committee of Shannxi Province(No.01JK229)
文摘The thermal behavior of the complex Pr[(C5H8NS2)3(C12H8N2)] in a dry nitrogen flow was examined by TG-DTG analysis. The TG-DTG investigations indicated that Pr[(C5H8NS2)3-(C12H8N2)] was decomposed into Pr2S3 and deposited carbon in one step where Pr2S3 predominated in the final products. The results of non-isothermal kinetic calculations showed that the decomposition stage was the random nucleation and subsequent growth mechanism (n = 2/3), the corresponding apparent activation energy ?was 115.89 kJ·mol-1 and the pre-expo-nential constant ln[A/s] was 7.8697. The empirical kinetics model equation was proposed as/(α) =3/2(1-α)[-ln(1-α)]1/3.The X-ray powder diffraction patterns of the thermal decomposition products at 800℃under N2 atmosphere show that the product can be indexed to the cubic Pr2S3 phase. The transmission electron microscopy (TEM) of the final product reveals the particle appearance of a diameter within 40 nm. The experimental results show that the praseodymium sulfide nanocrystal can be prepared from thermal decomposition of Pr[(C5H8NS2)3(C12H8N2)].
文摘The reaction of[CpMo(CO)_2]_2 with 8,8'-diquinolyl disulphide C_9H_6NSSNC_9H_6 resulted in the cleavage of Mo≡Mo triple bond to give a new nononuclear complex CpMo(CO)_2(N,S-C_9H_6NS)which was refluxed with PPh_3 in THF to form the title complex.The crystal structure of the title complex was determined by X-ray diffraction.
文摘The non-isothermal decomposition reaction of Nd[(C_5H_ 10NS_2)_3(C_ 12H_8N_2)] were carried out by means of TG-DTG and the thermal decomposition mechanism, and the associated kinetics was investigated. The kinetic parameters are obtained from an analysis of the TG-DTG curves at different heating rate by integral and differential methods. The most probable kinetic model function of the decomposition reaction is Maple Power of n=3/2, f(α)=2/3α -1/2 and the apparent activation energy E is 116.67 kJ·mol -1 and the pre-exponential factor lg[A/s -1] is 7.6891.
