The trisaccharide unit in lipopolysaccharide of Bordetella pertussis is important for immune recognition,but how the rare sugar 2-acetamido-4-methylamino-fucose in the trisaccharide unit is synthesized and transferred...The trisaccharide unit in lipopolysaccharide of Bordetella pertussis is important for immune recognition,but how the rare sugar 2-acetamido-4-methylamino-fucose in the trisaccharide unit is synthesized and transferred to the core of lipopolysaccharide in B.pertussis remains unclear.In this study,we demonstrated that the genes bplF,bplG,bplL and bplI are involved in the synthesis and transfer of 2-acetamido-4-methylamino-fucose to the core of lipopolysaccharide in B.pertussis.These genes were overexpressed with various combination in a recombinant E.coli strain which can synthesize B.pertussis corelipid A.Lipopolysaccharides were isolated from these strains and analyzed by using SDS-PAGE,ion chromatography and NMR.Based on these analyses,the mechanism of biosynthesis and transfer of 2-acetamido-4-methylamino-l-fucose to the core-lipid A in B.pertussis is proposed.展开更多
Background Increasing numbers of pertussis cases have been reported in recent years.The reported cases from Shenzhen Children's Hospital were close to one tenth of all cases in China.The epidemiology of antigenic ...Background Increasing numbers of pertussis cases have been reported in recent years.The reported cases from Shenzhen Children's Hospital were close to one tenth of all cases in China.The epidemiology of antigenic genotype and antibiotic resistance of circulating strains in children have been unknown in Shenzhen,southern China.The aim of this study was to describe the clinical features and explore the genotypes and antimicrobial susceptibility of circulating Bordetella pertussis among children in Shenzhen.Methods Data of hospitalized children with pertussis in Shenzhen Children's Hospital from August 2015 to April 2017 were collected.The genetic variability of isolates was investigated and Etest was performed for phenotypic susceptibility to erythromycin,azithromycin,clarithromycin,clindamycin,and trimethoprim/sulfamethoxazole.Results 469 children with pertussis confirmed by real-time quantitative polymerase chain reaction were hospitalized and strains were isolated from 105 patients.White blood cell count≥20×10^9/L and lymphocyte proportion≥60%were observed in 39.29%of infants younger than 3 months.The two predominant profiles of virulence-associated allelic genes were ptxA1/ptxC1/ptxPl/prnl(48.6%)and ptxA1/ptxC2/ptxP3/prn2(44.8%).Among the isolates,48.6%(51/105)were found resistant to macrolides.Conclusions These findings indicate that leukocytosis is not a sensitive indicator of pertussis.Isolates with the gene profile ptxP3/prn2 were highly circulating in Shenzhen and less resistant to macrolides,different from patterns observed in other parts of China.展开更多
Objective: To observe the effect of 654-2 on brain edema model induced by pertussis bacilli in rabbits. Methods: Brain edema model of 26 rabbits induced by pertussis bacilli was prepared for observation,their brain wa...Objective: To observe the effect of 654-2 on brain edema model induced by pertussis bacilli in rabbits. Methods: Brain edema model of 26 rabbits induced by pertussis bacilli was prepared for observation,their brain water content and brain glutamate level were determined before and after treatment. Results: 654-2could decline the water content of brain and increase the glutamate level in brain tissue of the treatment group as compared with group without treatment. Conclusion: 654-2 has protective effect on brain edema induced by pertussis bacilli.展开更多
基金supported by the National Key Research and Development Program of China(2018YFA0900300)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(CX10295).
文摘The trisaccharide unit in lipopolysaccharide of Bordetella pertussis is important for immune recognition,but how the rare sugar 2-acetamido-4-methylamino-fucose in the trisaccharide unit is synthesized and transferred to the core of lipopolysaccharide in B.pertussis remains unclear.In this study,we demonstrated that the genes bplF,bplG,bplL and bplI are involved in the synthesis and transfer of 2-acetamido-4-methylamino-fucose to the core of lipopolysaccharide in B.pertussis.These genes were overexpressed with various combination in a recombinant E.coli strain which can synthesize B.pertussis corelipid A.Lipopolysaccharides were isolated from these strains and analyzed by using SDS-PAGE,ion chromatography and NMR.Based on these analyses,the mechanism of biosynthesis and transfer of 2-acetamido-4-methylamino-l-fucose to the core-lipid A in B.pertussis is proposed.
基金This research was funded by Sanming Project of Medicine in Shenzhen(SZSM201512030)The funding organization had no involvement in study design,collection of data,the writing of draft,and the decision to submit the article for publication.
文摘Background Increasing numbers of pertussis cases have been reported in recent years.The reported cases from Shenzhen Children's Hospital were close to one tenth of all cases in China.The epidemiology of antigenic genotype and antibiotic resistance of circulating strains in children have been unknown in Shenzhen,southern China.The aim of this study was to describe the clinical features and explore the genotypes and antimicrobial susceptibility of circulating Bordetella pertussis among children in Shenzhen.Methods Data of hospitalized children with pertussis in Shenzhen Children's Hospital from August 2015 to April 2017 were collected.The genetic variability of isolates was investigated and Etest was performed for phenotypic susceptibility to erythromycin,azithromycin,clarithromycin,clindamycin,and trimethoprim/sulfamethoxazole.Results 469 children with pertussis confirmed by real-time quantitative polymerase chain reaction were hospitalized and strains were isolated from 105 patients.White blood cell count≥20×10^9/L and lymphocyte proportion≥60%were observed in 39.29%of infants younger than 3 months.The two predominant profiles of virulence-associated allelic genes were ptxA1/ptxC1/ptxPl/prnl(48.6%)and ptxA1/ptxC2/ptxP3/prn2(44.8%).Among the isolates,48.6%(51/105)were found resistant to macrolides.Conclusions These findings indicate that leukocytosis is not a sensitive indicator of pertussis.Isolates with the gene profile ptxP3/prn2 were highly circulating in Shenzhen and less resistant to macrolides,different from patterns observed in other parts of China.
文摘Objective: To observe the effect of 654-2 on brain edema model induced by pertussis bacilli in rabbits. Methods: Brain edema model of 26 rabbits induced by pertussis bacilli was prepared for observation,their brain water content and brain glutamate level were determined before and after treatment. Results: 654-2could decline the water content of brain and increase the glutamate level in brain tissue of the treatment group as compared with group without treatment. Conclusion: 654-2 has protective effect on brain edema induced by pertussis bacilli.
