Genetic engineering of the phosphocarrier protein NPr of the Escherichia coli phosphotransferase system selectively improves sugar uptake activity.
J Biol Chem
; 287(35): 29931-9, 2012 Aug 24.
Article
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| MEDLINE
| ID: mdl-22767600
The Escherichia coli phosphoenolpyruvate:sugar phosphotransferase system (PTS) in prokaryotes mediates the uptake and phosphorylation of its numerous substrates through a phosphoryl transfer chain where a phosphoryl transfer protein, HPr, transfers its phosphoryl group to any of several sugar-specific Enzyme IIA proteins in preparation for sugar transport. A phosphoryl transfer protein of the PTS, NPr, homologous to HPr, functions to regulate nitrogen metabolism and shows virtually no enzymatic cross-reactivity with HPr. Here we describe the genetic engineering of a "chimeric" HPr/NPr protein, termed CPr14 because 14 amino acid residues of the interface were replaced. CPr14 shows decreased activity with most PTS permeases relative to HPr, but increases activity with the broad specificity mannose permease. The results lead to the proposal that HPr is not optimal for most PTS permeases but instead represents a compromise with suboptimal activity for most PTS permeases. The evolutionary implications are discussed.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Proteínas Bacterianas
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Proteínas Recombinantes de Fusión
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Sistema de Fosfotransferasa de Azúcar del Fosfoenolpiruvato
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Proteínas Portadoras
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Ingeniería Genética
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Proteínas de Escherichia coli
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Escherichia coli
Idioma:
En
Revista:
J Biol Chem
Año:
2012
Tipo del documento:
Article
Pais de publicación:
Estados Unidos