Linked Life Data

17439954

Source:http://linkedlifedata.com/resource/pubmed/id/17439954

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
23
pubmed:dateCreated
2007-6-4
pubmed:abstractText
The ArsA ATPase is the catalytic subunit of the ArsAB pump encoded by the arsRDABC operon of Escherichia coli plasmid R773. ArsD is a metallochaperone that delivers As(III) to ArsA, increasing its affinity for As(III), thus conferring resistance to environmental concentrations of arsenic. R773 ArsD is a homodimer with three vicinal cysteine pairs, Cys(12)-Cys(13), Cys(112)-Cys(113), and Cys(119)-Cys(120), in each subunit. Each vicinal pair binds As(III) or Sb(III). Alignment of the primary sequence of homologues of ArsD indicates that only the first vicinal cysteine pair, Cys(12)-Cys(13), and an additional cysteine, Cys(18), are conserved. The effect of cysteine-to-alanine substitutions and truncations were examined. By yeast two-hybrid analysis, nearly all of the ArsD mutants were able to interact with wild type ArsD, indicating that the mutations do not interfere with dimerization. ArsD mutants with alanines substituting for Cys(112), Cys(113), Cys(119), or Cys(120) individually or in pairs or truncations lacking the vicinal pairs retained ability to interact with ArsA and to activate its ATPase activity. Cells expressing these mutants retained ArsD-enhanced As(III) efflux and resistance. In contrast, mutants with substitutions of conserved Cys(12), Cys(13), or Cys(18), individually or in pairs, were unable to activate ArsA or to enhance the activity of the ArsAB pump. We propose that ArsD residues Cys(12), Cys(13), and Cys(18), but not Cys(112), Cys(113), Cys(119), or Cys(120), are required for delivery of As(III) to and activation of the ArsAB pump.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
8
pubmed:volume
282
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
16783-91
pubmed:dateRevised
2010-9-2
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
ArsD residues Cys12, Cys13, and Cys18 form an As(III)-binding site required for arsenic metallochaperone activity.
pubmed:affiliation
Department of Biochemistry and Molecular Biology, Wayne State University, School of Medicine, Detroit, Michigan 48201, USA.
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural