Absence of dbpA Results in the Delayed Initiation of DNA Replication in Escherichia coli

doi:10.13560/j.cnki.biotech.bull.1985.2018-0538

Abstract

Abstract: This work is to investigate the effect of ribosome maturation factor dbpA on the initiation of DNA replication in Escherichia coli. The phenotype changes such as DNA replication pattern,doubling time and cell size of ΔdbpA deletion mutants were observed,and the temperature sensitivity test and protein quantitative experiment were used to study the action mechanisms of dbpA. The results showed that the mild phenotypic change such as the delayed initiation of DNA replication,prolonged doubling time,declined cell size occurred in ΔdbpA cells compared with wild type BW25113. Moreover,the change in LB medium was more obvious than that in ABTGcasa medium. The temperature sensitivity test demonstrated that DbpA did not interact with DnaA,DnaB or DnaC protein. The protein quantitative experiment revealed that the amount of total protein and DnaA protein in ΔdbpA cell decreased,and the decrease degree was greater in LB medium than in ABTGcasa medium. Thus,the absence of dbpA leads to the delayed initiation of E. coli DNA replication,the reason of which may be that dbpA affects the protein synthesis through influencing the assembly or translation activity of ribosome,and subsequently reduces the total protein and DnaA protein in cells. This study provides a reference to clarify the function of dbpA.

Key words: dbpA, ribosome maturation factor, DNA replication initiation, bacterial phenotype

ZHANG Shu-jun, Wunier, DI Jian-jun, ZHANG Guo-wen, XU Ya-nan. Absence of dbpA Results in the Delayed Initiation of DNA Replication in Escherichia coli[J]. Biotechnology Bulletin, 2018, 34(12): 172-178.

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