Linked Life Data

8218185

Source:http://linkedlifedata.com/resource/pubmed/id/8218185

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
41
pubmed:dateCreated
1993-11-26
pubmed:abstractText
The mannitol permease, an enzyme II of the phosphoenolpyruvate-dependent carbohydrate phosphotransferase system (PTS) of Escherichia coli, carries out the transport and phosphorylation of D-mannitol in this organism. Previous studies have shown that His-554 and Cys-384 in the mannitol permease are sequentially phosphorylated in reactions necessary for the transport and phosphorylation of the substrate. These residues are located in a large cytoplasmic domain of the protein. Interaction of the permease with mannitol, and its membrane translocation, however, must involve the N-terminal, transmembrane domain (EIIC domain) of the protein. In this report, we use site-directed mutagenesis and mutant complementation to investigate the role of His-195 in the EIIC domain of the mannitol permease, a residue that is conserved in many PTS permeases. In a previous report [Weng, Q.-P., Elder, J., & Jacobson, G. R. (1992) J. Biol. Chem. 267, 19529-19535], we inferred a role for His-195 that involves its hydrogen-bonding ability. Here we show that His-195 plays a role in high-affinity mannitol binding. Moreover, mutant complementation studies show that a functional His-195 must be on the same subunit as a functional Cys-384 in a permease dimer for phosphotransfer to mannitol to occur. These results and kinetic studies of His-195 mutant proteins imply that His-195 also may play an important role in this phosphotransfer reaction. His-195 is predicted to be in a cytoplasmic "loop" in the EIIC domain of the mannitol permease, in which several other residues have been shown to have roles in mannitol permease activity.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
19
pubmed:volume
32
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
11211-6
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
Role of a conserved histidine residue, His-195, in the activities of the Escherichia coli mannitol permease.
pubmed:affiliation
Department of Biology, Boston University, Massachusetts 02215.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.