Cytoplasmic Escherichia coli ADP sugar pyrophosphatase binds to cell membranes in response to extracellular signals as the cell population density increases.
FEMS Microbiol Lett
; 288(1): 25-32, 2008 Nov.
Article
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| MEDLINE
| ID: mdl-18778276
ABSTRACT
ADP sugar pyrophosphatase (AspP) is a member of the 'Nudix' (Nucleoside diphosphate linked to some other moiety X) hydrolase family of enzymes that catalyzes the hydrolytic breakdown of ADP-glucose (ADPG) linked to glycogen biosynthesis. In a previous work, we showed that AspP activity is strongly enhanced by both glucose-1,6-bisphosphate and nucleotide-sugars, and by macromolecular crowding. In this work, we show that AspP binds to cell membranes as the bacterial population density increases, c. 30% of the total enzyme remaining membrane associated as glycogen depletes during the stationary phase. This process is not dependent on the stationary transcription factor RpoS, the producer of the bacterial quorum-sensing autoinducer 2 (LuxS), the presence of glycogen granules or glucose availability, but is stimulated by small soluble heat-labile molecule(s) occurring in cell-free spent supernatants of stationary cultures that are acid stabile and base labile. These data further point to AspP as a highly regulated enzyme, and provide a first set of evidences indicating that glycogen metabolism is subjected to regulation by intercellular communication in Escherichia coli.
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1
Banco de datos:
MEDLINE
Asunto principal:
Pirofosfatasas
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Proteínas Bacterianas
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Escherichia coli
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Espacio Extracelular
Idioma:
En
Año:
2008
Tipo del documento:
Article