Involvement of the central loop of the lactose permease of Escherichia coli in its allosteric regulation by the glucose-specific enzyme IIA of the phosphoenolpyruvate-dependent phosphotransferase system.
J Bacteriol
; 178(20): 6082-6, 1996 Oct.
Article
en En
| MEDLINE
| ID: mdl-8830713
ABSTRACT
Allosteric regulation of several sugar transport systems such as those specific for lactose, maltose and melibiose in Escherichia coli (inducer exclusion) is mediated by the glucose-specific enzyme IIA (IIAGlc) of the phosphoenolpyruvatesugar phosphotransferase system (PTS). Deletion mutations in the cytoplasmic N and C termini of the lactose permease protein, LacY, and replacement of all cysteine residues in LacY with other residues did not prevent IIAGlc-mediated inhibition of lactose uptake, but several point and insertional mutations in the central cytoplasmic loop of this permease abolished transport regulation and IIAGlc binding. The results substantiate the conclusion that regulation of the lactose permease in E. coli by the PTS is mediated by a primary interaction of IIAGlc with the central cytoplasmic loop of the permease.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Proteínas de Transporte de Membrana
/
Proteínas de Transporte de Monosacáridos
/
Sistema de Fosfotransferasa de Azúcar del Fosfoenolpiruvato
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Proteínas de Escherichia coli
/
Simportadores
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Escherichia coli
Idioma:
En
Revista:
J Bacteriol
Año:
1996
Tipo del documento:
Article
País de afiliación:
Estados Unidos