Functional characterization of Helicobacter pylori DnaB helicase

被引：43

作者：

Soni, RK

Mehra, P

Choudhury, NR

Mukhopadhyay, G

Dhar, SK ^{[1
]}

机构：

[1] Jawaharlal Nehru Univ, Special Ctr Mol Med, New Delhi 110067, India

[2] Int Ctr Genet Engn & Biotechnol, New Delhi 110067, India

来源：

NUCLEIC ACIDS RESEARCH | 2003年 / 31卷 / 23期

关键词：

D O I：

10.1093/nar/gkg895

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

Helicobacter pylori causes gastric ulcer diseases and gastric adenocarcinoma in humans. Not much is known regarding DNA replication in H.pylori that is important for cell survival. Here we report the cloning, expression and characterization of H.pylori DnaB (HpDnaB) helicase both in vitro and in vivo. Among the DnaB homologs, only Escherichia coli DnaB has been studied extensively. HpDnaB showed strong 5' to 3' helicase and ATPase activity. Interestingly, H.pylori does not have an obvious DnaC homolog which is essential for DnaB loading on the E.coli chromosomal DNA replication origin (oriC). However, HpDnaB can functionally complement the E.coli DnaB temperature-sensitive mutant at the non-permissive temperature, confirming that HpDnaB is a true replicative helicase. Escherichia coli DnaC co-eluted in the same fraction with HpDnaB following gel filtration analysis suggesting that these proteins might physically interact with each other. It is possible that a functional DnaC homolog is present in H.pylori. The complete characterization of H.pylori DnaB helicase will also help the comparative analysis of DnaB helicases among bacteria.

引用

页码：6828 / 6840

页数：13

共 42 条

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