Linked Life Data

15451673

Source:http://linkedlifedata.com/resource/pubmed/id/15451673

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2004-9-28
pubmed:abstractText
FlhA is an integral membrane component of the Salmonella type III flagellar protein export apparatus. It consists of 692 amino acid residues and has two domains: the N-terminal transmembrane domain consisting of the first 327 amino acid residues, and the C-terminal cytoplasmic domain (FlhAC) comprising the remainder. Here, we have investigated the structure and function of FlhAC. DNA sequence analysis revealed that temperature-sensitive flhA mutations, which abolish flagellar protein export at the restrictive temperature, lie in FlhAC, indicating that FlhAC plays an important role in the protein export process. Limited proteolysis of purified His-FlhAC by trypsin and V8 showed that only a small part of FlhAC near its N terminus (residues 328-351) is sensitive to proteolysis. FlhAC38K, the smallest fragment produced by V8 proteolysis, is monomeric and has a spherical shape as judged by analytical gel filtration chromatography and analytical ultracentrifugation. The far-UV CD spectrum of FlhAC38K showed that it contains considerable amounts of secondary structure. FlhA(Delta328-351) missing residues 328-351 failed to complement the flhA mutant, indicating that the proteolytically sensitive region of FlhA is important for its function. FlhA(Delta328-351) was inserted into the cytoplasmic membrane, and exerted a strong dominant negative effect on wild-type cells, suggesting that it retains the ability to interact with other export components within the cytoplasmic membrane. Overproduced FlhAC38K inhibited both motility and flagellar protein export of wild-type cells to some degree, suggesting that FlhAC38K is directly involved in the translocation reaction. Amino acid residues 328-351 of FlhA appear to be a relatively flexible linker between the transmembrane domain and FlhAC38K.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0022-2836
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
343
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
457-66
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Structural and functional analysis of the C-terminal cytoplasmic domain of FlhA, an integral membrane component of the type III flagellar protein export apparatus in Salmonella.
pubmed:affiliation
Dynamic NanoMachine Project, ICORP, JST, 1-3 Yamadaoka, Suita, Osaka 565-0871, Japan.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.