检索结果-南通市图书馆

Characterization of NADase-Inactive NAD<sup>+</sup>Glycohydrolase in <i>Streptococcus pyogenes</i>

Advances in Microbiology 2013年第1期3卷 91-100页

作者： Ichiro Tatsuno masanori isaka Tadao Hasegawa Department of Bacteriology Graduate School of Medical Sciences Nagoya City UniversityNagoya Japan

Background: Streptococcus pyogenes secretes NAD+ glycohydrolase (NADase, also known as SPN or Nga). All S. pyogenes strains examined to date possess the gene that encodes SPN (spn), but some strains produce SPN that lacks detectable NADase activity. Although there is much evidence to support that SPN’s NADase activity contributes to virulence, there is very little evidence that NADase-inactive SPN has detectable functions. Results: In order to characterize the NADase-inactive SPN, we firstly attempted to clone the NADase-inactive spn allele in Escherichia coli. Although we obtained recombinants which were shown to have the correct size insert, all had some mutations in the spn allele. Therefore, we attempted to change the mutated nucleotides back to the original nucleotides. While a nucleotide mutagenesis (inverse PCR method) easily changed a target nucleotide of control genes back to the original nucleotides, the mutations of NADase-inactive spn allele were never successfully converted back to the original nucleotides. Finally the mutant spn alleles were sub-cloned into another vector (pLZ12-Km2), which is maintained in both E. coli and S. pyogenes. The resultant plasmids were subjected to nucleotide mutagenesis using inverse PCR;the resultant mutagenized plasmid DNAs were used to transform both E. coli and S. pyogenes strains. We observed successful nucleotide substitutions back to the original spn nucleotide sequence in S. pyogenes transformants, but not in E. coli transformants. Thus, the NADase-inactive spn allele was successfully cloned in S. pyogenes, but not in E. coli. However, we could not find an association with NADase-inactive spn allele and virulence in a mouse infection model. Conclusions: These results suggest that NADase-inactive spn allele has some toxic effect to E. coli, but not S. pyogenes. This effect may due to an as of yet unknown function attributable to NADase-inactive SPN.

关键词： Streptococcus pyogenes NAD+ Glycohydrolase NADase SPN Streptococcal SF370

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：