Linked Life Data

15794654

Source:http://linkedlifedata.com/resource/pubmed/id/15794654

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
13
pubmed:dateCreated
2005-3-29
pubmed:abstractText
In an effort to probe the structure of a group Bb metallo-beta-lactamase, Co(II)-substituted ImiS was prepared and characterized by electronic absorption, NMR, and EPR spectroscopies. ImiS containing 1 equiv of Co(II) (Co(II)(1)-ImiS) was shown to be catalytically active. Electronic absorption studies of Co(II)(1)-ImiS revealed the presence of two distinct features: (1) an intense sulfur to Co(II) ligand to metal charge transfer band and (2) less intense, Co(II) ligand field transitions that suggest 4-coordinate Co(II) in Co(II)(1)-ImiS. (1)H NMR studies of Co(II)(1)-ImiS suggest that one histidine, one aspartic acid, and one cysteine coordinate the metal ion in Co(II)(1)-ImiS. The addition of a second Co(II) to Co(II)(1)-ImiS did not result in any additional solvent-exchangeable NMR resonances, strongly suggesting that the second Co(II) does not bind to a site with histidine ligands. EPR studies reveal that the metal ion in Co(II)(1)-ImiS is 4-coordinate and that the second Co(II) is 5/6 coordinate. Taken together, these data indicate that the catalytic site in ImiS is the consensus Zn(2) site, in which Co(II) (and by extrapolation Zn(II)) is 4-coordinate and bound by Cys221, His263, Asp120, and probably one solvent water molecule. These studies also show that the second, inhibitory metal ion does not bind to the consensus Zn(1) site and that the metal ion binds at a site significantly removed from the active site. These results give the first structural information on metallo-beta-lactamase ImiS and suggest that the second metal binding site in ImiS may be targeted for inhibitors.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
5
pubmed:volume
44
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
5168-76
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Spectroscopic studies on cobalt(II)-substituted metallo-beta-lactamase ImiS from Aeromonas veronii bv. sobria.
pubmed:affiliation
Department of Chemistry and Biochemistry, 112 Hughes Hall, Miami University, Oxford, Ohio 45056, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.