Sensitivity of efflux-driven carrier turnover to external pH in mutants of the Escherichia coli lactose carrier that have tyrosine or phenylalanine substituted for histidine-322. A comparison of lactose and melibiose.

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Article

Sensitivity of efflux-driven carrier turnover to external pH in mutants of the Escherichia coli lactose carrier that have tyrosine or phenylalanine substituted for histidine-322. A comparison of lactose and melibiose.

The Journal of biological chemistry - 25 Feb 1990

King S C, Wilson T H

Abstract excerpt

Two Escherichia coli lactose carrier mutants (tyrosine or phenylalanine substituted for histidine 322) were studied under conditions of net efflux or equilibrium exchange. Net lactose efflux by either mutant was 10-20-fold slower than by the parent and was sensitive to extracellular pH (5.6-8.0). The presence of extracellular lactose (equilibrium exchange) failed to accelerate loss of [14C]lactose, indicating...

Topics

Disaccharides
Edetic Acid
Escherichia coli
Escherichia coli Proteins
Histidine
Hydrogen-Ion Concentration
Kinetics
Lactose
Melibiose
Membrane Transport Proteins

Methodology Data sources Editorial policy Privacy About Contact Helena Bioinformatics

Models, Theoretical

Monosaccharide Transport Proteins

Mutation

Phenylalanine

Symporters

Tyrosine

Source

Open in PubMed

Identifiers

PMID: 2105944

Provenance

PubMed metadata and Literature Corpus relationships. Corpus snapshot updated 29 Aug 2026. Prepared record publication-2105944-2026-08-29.1. Manifest publication-graph-cohort-2026-08-29.1.

Source receipt: PubMed via Helena Literature Corpus, retrieved 29 Aug 2026.

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Sensitivity of efflux-driven carrier turnover to external pH in mutants of the Escherichia coli lactose carrier that have tyrosine or phenylalanine substituted for histidine-322. A comparison of lactose and melibiose.PMID 2105944Read ↗

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