Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
16
pubmed:dateCreated
2011-7-29
pubmed:abstractText
HAMP domains are sensory transduction modules that connect input and output domains in diverse signaling proteins from archaea, bacteria, and lower eukaryotes. Here, we employed in vivo disulfide cross-linking to explore the structure of the HAMP domain in the Escherichia coli aerotaxis receptor Aer. Using an Aer HAMP model based on the structure of Archaeoglobus fulgidus Af1503-HAMP, the closest residue pairs at the interface of the HAMP AS-1 and AS-2' helices were determined and then replaced with cysteines and cross-linked in vivo. Except for a unique discontinuity in AS-2, the data suggest that the Aer HAMP domain forms a parallel four-helix bundle that is similar to the structure of Af1503. The HAMP discontinuity was associated with a segment of AS-2 that was recently shown to interact with the Aer-PAS sensing domain. The four-helix HAMP bundle and its discontinuity were maintained in both the kinase-on and kinase-off states of Aer, although differences in the rates of disulfide formation also indicated the existence of different HAMP conformations in the kinase-on and kinase-off states. In particular, the kinase-on state was accompanied by significantly increased disulfide formation rates at the distal end of the HAMP four-helix bundle. This indicates that HAMP signaling may be associated with a tilting of the AS-1 and AS-2' helices, which may be the signal that is transmitted to the kinase control region of Aer.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
1098-5530
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
193
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4095-103
pubmed:meshHeading
pubmed:year
2011
pubmed:articleTitle
Different conformations of the kinase-on and kinase-off signaling states in the Aer HAMP domain.
pubmed:affiliation
Division of Microbiology and Molecular Genetics, Loma Linda University, Loma Linda, CA 92350, USA.
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural