Nucleosidpolyphosphate: Vorkommen, Metabolismus und Funktion

Abstract

Procaryotes have regulatory systems allowing to vary the metabolism in response to nutritional variations, to reduce the growth, and to start development. Nucleoside polyphosphates are mediators of coordinated alterations of metabolism. In this review, after a brief recall of the characteristics of the stringent response, the occurrence, determinations, and the metabolism of the nucleoside polyphosphates are presented. The representation of the pleiotropic effects includes the regulation of the protein synthesis and of the protein synthesis apparatus, of the protein turnover, of the N- and carbohydrate metabolism, of the formation of cell membranes and cell walls as well as the possible function of the development.

The role of guanosine-3',5'-bis-pyrophosphate in mediating antimicrobial activity of the antibiotic 3,5-dihydroxy-4-ethyl-trans-stilbene

“…The modest reduction of ATP accumulation in ES-treated cells suggests that the primary effect of ES is not directed at bacterial oxidative phosphorylation. Under our experimental conditions, ES did not produce an increase in other regulatory nucleotides such as AppppA (29), pGpp (17), or ppGp (36), which have previously been suggested to possess regulatory functions (41). However, an effect on the levels of pppGpp in some bacteria cannot be ruled out, since certain concentrations of ES appeared to induce an increase in pppGpp levels in M. luteus (data not shown).…”

“…The control of cellular and metabolic processes in bacterial cells can be mediated through a number of regulatory proteins and nucleotides (17,29,36,41). For example, the nucleotide guanosine-3',5'-bis-pyrophosphate (ppGpp) has been implicated in the regulation of a wide array of distinct physiological processes in Escherichia coli and a few other bacteria (8,15,33,39,42).…”

3H‐Thymidininkorporation nach Isoleucinlimitation in “stringent” und “relaxed” kontrollierten Stämmen von Escherichia coli

“…Dabei handelt es sich uni eine aul3er-ordentlich komplexe Beeinflussung verschiedenster Bereiche des Metabolismus, wovon der negativen Kontrolle anaboler Prozesse wie der Synthese von rHNA und ribosomaler Proteine sowie weiterer Translationsproteine, von Zellwandbestandteilen oder Membrankoniponenten eine Schliisselrolle zukonimt (vgl. ubersichten bei GALLANT 1979, RIEDEL 1983, HECKER 1983.…”