SCIENCE@home

THE PATHWAY AND CONTROL OF SERINE BIOSYNTHESIS IN ESCHERICHIA COLI.

L. Pizer

Published 1963 in Journal of Biological Chemistry

ABSTRACT

The work of Ichihara and Greenberg (1) provides evidence that serine biosynthesis in mammalian liver involves the following enzymic reactions: oxidation of the glycolytic intermediate 3-phosphoglycerate (I) to phosphohydroxypyruvate (II), subsequent transamination to phosphoserine (III), and finally dephosphorylation to serine (IV). Sallach and Willis (2, 3) have described analogous enzymic reactions in which the intermediates are the nonphosphorylated compounds, glycerate and hydroxypyruvate. Two enzymes of the phosphorylated pathway, the transaminase and the phosphatase, and one enzyme of the nonphosphorylated pathway, the dehydrogenase, were discovered in Escherichia coli extracts by Smith et al. (4), but it was not possible from their study to determine which, if either, of these pathways was physiologically important. This paper describes work designed to establish the nature of the major biosynthetic pathway in E. coli and to esplain at the enzyme level the observation of Roberts et al. (5) that an exogenous supply of serine limited endogenous serine synthesis from glucose. Enzymes that convert phosphoglycerate to serine via the phosphorylated intermediates, hydroxypyruvate-P and serine-P, have been found in extracts of E. coli strain W, and since a mutation that disrupts this sequence results in a growth requirement for serine or glycine, it is concluded that this is the major biosynthetic pathway in this strain. The first enzyme in this sequence is strongly inhibited by L-serine and thereby establishes a feedback system that controls serine production from glucose. Umbarger and Umbarger (6) have recently found that the phosphorylated pathway functions in Salmonella typhimurium and that the initial enzyme is sensitive to serine inhibition.

PUBLICATION RECORD

CITATION MAP

EXTRACTION MAP

CLAIMS

  • No claims are published for this paper.

CONCEPTS

  • No concepts are published for this paper.

REFERENCES

Showing 1-22 of 22 references · Page 1 of 1

CITED BY

Showing 1-100 of 198 citing papers · Page 1 of 2

12
Next