Linked Life Data

9462429

Source:http://linkedlifedata.com/resource/pubmed/id/9462429

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1998-3-12
pubmed:abstractText
Klebsiella oxytoca strain HB60 is highly resistant to cefoperazone and aztreonam (MICs = 128 mg/L). It produces a chromosomally encoded beta-lactamase of pI 5.7 which was highly efficient against penicillins, first-generation cephalosporins and cefoperazone, a non-oxyimino third-generation cephalosporin. Aztreonam and oxyimino broad-spectrum cephalosporins were less good substrates. The beta-lactamase activity was susceptible to inhibition by clavulanic acid (IC50 = 1 microM). The enzyme purified to homogeneity had a specific activity towards benzylpenicillin of 3670 U/mg. The 263 amino acid residues of the protein were sequenced by Edman degradation of proteolytic peptides. The beta-lactamase was shown to belong to the OXY-2 group as it had only one amino acid substitution (Asn for Asp at ABL position 197) compared with the beta-lactamase (pI 5.2) from the aztreonam-susceptible K. oxytoca strain SL911 and two substitutions (Ala223 for Val and Asp255 for Asn) compared with the beta-lactamase (pI 6.4) from the aztreonam-resistant K. oxytoca strain D488. These three OXY-2-group enzymes behave in the same way towards beta-lactam antibiotics. The variability in the resistance of these K. oxytoca strains would thus seem to be due to variation in the level of production of the beta-lactamases rather than to structural alteration of the enzymes.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0305-7453
pubmed:author
pubmed:issnType
Print
pubmed:volume
40
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
789-95
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Characterization and amino acid sequence of the OXY-2 group beta-lactamase of pI 5.7 isolated from aztreonam-resistant Klebsiella oxytoca strain HB60.
pubmed:affiliation
Laboratoire de Chimie, URA 401, IFR 63 CNRS, Muséum National d'Histoire Naturelle, Paris, France.
pubmed:publicationType
Journal Article, Comparative Study