Work

Guanosine Tetra- and Pentaphosphate Promote Accumulation of Inorganic Polyphosphate in Escherichia coli

Year: 1997

Type: article

Abstract: High levels of guanosine tetraphosphate (ppGpp) and guanosine pentaphosphate (pppGpp), generated in response to amino acid starvation in Escherichia coli, lead to massive accumulations of inorganic polyphosphate (polyP). Inasmuch as the activities of the principal enzymes that synthesize and degrade polyP fluctuate only slightly, the polyP accumulation can be attributed to a singular and profound inhibition by pppGpp and/or ppGpp of the hydrolytic breakdown of polyP by exopolyphosphatase, thereby blocking the dynamic turnover of polyP. The Ki values of 10 microM for pppGpp and 200 microM for ppGpp are far below the concentrations of these nucleotides in nutritionally stressed cells. In the complex metabolic network of pppGpp and ppGpp, the greater inhibitory effect of pppGpp (compared with ppGpp) leading to the accumulation of polyP, may have some significance in the relative roles played by these regulatory compounds.

Source: Journal of Biological Chemistry

DOI: 10.1074/jbc.272.34.21240

Authors: Akio Kuroda, Helen Murphy, Michael Cashel, Arthur Kornberg

Institutions: Stanford Medicine, Stanford University, National Institutes of Health, Eunice Kennedy Shriver National Institute of Child Health and Human Development

Language: English

Topic: Bacterial Genetics and Biotechnology

Subfield: Genetics

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

Open Access status: hybrid

Estimated APC paid: $3,430

OpenAlex ID: W2087345689

FWCI: 4.926

Cites: 18

Cited by: 250

Related to: 10