(p)ppGpp and the bacterial cell cycle

Journal of biosciences

Aanisa Nazir¹  Rajendran Harinarayanan1¹ 

[1] Laboratory of Bacterial Genetics, Center for DNA Fingerprinting and Diagnostics, Hyderabad, India$$

关键词: (p)ppGpp;    bacteria;    cell cycle;    cell division;    replication;   

DOI  :  

来源: Indian Academy of Sciences

【 摘 要 】

Genes of the Rel/Spo homolog (RSH) superfamily synthesize and/or hydrolyse the modified nucleotides pppGpp/ppGpp (collectively referred to as (p)ppGpp) and are prevalent across diverse bacteria and in plant chloroplasts. Bacteria accumulate (p)ppGpp in response to nutrient deprivation (generically called the stringent response) and elicit appropriate adaptive responses mainly through the regulation of transcription. Although at different concentrations (p)ppGpp affect the expression of distinct set of genes, the two well-characterized responses are reduction in expression of the protein synthesis machinery and increase in the expression of genes coding for amino acid biosynthesis. In Escherichia coli, the cellular (p)ppGpp level inversely correlates with the growth rate and increasing its concentration decreases the steady state growth rate in a defined growth medium. Since change in growth rate must be accompanied by changes in cell cycle parameters set through the activities of the DNA replication and cell division apparatus, (p)ppGpp could coordinate protein synthesis (cell mass increase) with these processes. Here we review the role of (p)ppGpp in bacterial cell cycle regulation.

【 授权许可】

Unknown