Linked Life Data

10639363

Source:http://linkedlifedata.com/resource/pubmed/id/10639363

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2000-3-23
pubmed:abstractText
We describe Klebsiella pneumoniae 15571, a clinical isolate resistant to ceftazidime MIC = 32 microg/ml) and piperacillin-tazobactam (MICs = 1,024 and 128 microg/ml). K. pneumoniae 15571 expresses a single beta-lactamase with a pI of 7.6. However, when cloned in a high-copy-number vector in Escherichia coli, this bla(SHV-1) gene did not confer resistance to ceftazidime, a spectrum consistent with the nucleotide sequence, which was nearly identical to those of previously described bla(SHV-1) genes. Outer membrane protein (OMP) analysis of K. pneumoniae 15571 revealed a decrease in the quantity of a minor 45-kDa OMP in comparison to that in K. pneumoniae 44NR, a low-level ampicillin-resistant strain that also expresses a chromosomally determined bla(SHV-1). Crude beta-lactamase enzyme extracts from K. pneumoniae 15571 produced roughly 200-fold more beta-lactamase activity than K. pneumoniae 44NR. Northern hybridization analysis revealed that this difference was explainable by quantifiable differences in transcription of the bla(SHV-1) gene in the two strains. Primer extension analysis of bla(SHV-1) mRNA from K. pneumoniae 15571 and 44NR indicated that the transcriptional start sites were identical in the two strains. DNA sequencing of the promoter regions upstream of the of bla(SHV-1) open reading frames in the two K. pneumoniae strains revealed an A-->C change in the second position of the -10 region in K. pneumoniae 44NR compared to that in 15571. Site-directed mutagenesis of the cloned K. pneumoniae 15571 bla(SHV-1), in which the A in the second position of the 15571 -10 region was changed to a C, resulted in a substantial lowering of the MIC of ampicillin. When the levels of beta-lactamase enzyme expression in E. coli were compared, the bla(SHV-1) downstream of the altered -10 region produced 17-fold less beta-lactamase enzyme. These results indicate that elevated levels of ceftazidime resistance can result from a combination of increased enzyme production and minor OMP changes and that levels of chromosomally encoded SHV-1 beta-lactamase production can vary substantially with a single-base-pair change in promoter sequence.
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/10639363-10217760, http://linkedlifedata.com/resource/pubmed/commentcorrection/10639363-1952834, http://linkedlifedata.com/resource/pubmed/commentcorrection/10639363-2033379, http://linkedlifedata.com/resource/pubmed/commentcorrection/10639363-2073110, http://linkedlifedata.com/resource/pubmed/commentcorrection/10639363-2197339, http://linkedlifedata.com/resource/pubmed/commentcorrection/10639363-2221867, http://linkedlifedata.com/resource/pubmed/commentcorrection/10639363-2982966, http://linkedlifedata.com/resource/pubmed/commentcorrection/10639363-319999, http://linkedlifedata.com/resource/pubmed/commentcorrection/10639363-3260490, http://linkedlifedata.com/resource/pubmed/commentcorrection/10639363-3533626, http://linkedlifedata.com/resource/pubmed/commentcorrection/10639363-4564689, http://linkedlifedata.com/resource/pubmed/commentcorrection/10639363-6092432, http://linkedlifedata.com/resource/pubmed/commentcorrection/10639363-6326054, http://linkedlifedata.com/resource/pubmed/commentcorrection/10639363-6605714, http://linkedlifedata.com/resource/pubmed/commentcorrection/10639363-8390809, http://linkedlifedata.com/resource/pubmed/commentcorrection/10639363-8537652, http://linkedlifedata.com/resource/pubmed/commentcorrection/10639363-8834877, http://linkedlifedata.com/resource/pubmed/commentcorrection/10639363-9021210, http://linkedlifedata.com/resource/pubmed/commentcorrection/10639363-9055993, http://linkedlifedata.com/resource/pubmed/commentcorrection/10639363-9174192, http://linkedlifedata.com/resource/pubmed/commentcorrection/10639363-9222043, http://linkedlifedata.com/resource/pubmed/commentcorrection/10639363-9668979, http://linkedlifedata.com/resource/pubmed/commentcorrection/10639363-9925535
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0066-4804
pubmed:author
pubmed:issnType
Print
pubmed:volume
44
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
362-7
pubmed:dateRevised
2009-11-18
pubmed:meshHeading
pubmed-meshheading:10639363-Bacterial Outer Membrane Proteins, pubmed-meshheading:10639363-Base Sequence, pubmed-meshheading:10639363-Biological Transport, pubmed-meshheading:10639363-Ceftazidime, pubmed-meshheading:10639363-Cephalosporins, pubmed-meshheading:10639363-Chromosomes, pubmed-meshheading:10639363-Cloning, Molecular, pubmed-meshheading:10639363-DNA, Bacterial, pubmed-meshheading:10639363-Drug Resistance, Microbial, pubmed-meshheading:10639363-Enzyme Inhibitors, pubmed-meshheading:10639363-Gene Expression Regulation, Bacterial, pubmed-meshheading:10639363-Humans, pubmed-meshheading:10639363-Klebsiella pneumoniae, pubmed-meshheading:10639363-Microbial Sensitivity Tests, pubmed-meshheading:10639363-Molecular Sequence Data, pubmed-meshheading:10639363-Nucleic Acid Hybridization, pubmed-meshheading:10639363-Penicillanic Acid, pubmed-meshheading:10639363-Penicillins, pubmed-meshheading:10639363-Piperacillin, pubmed-meshheading:10639363-Promoter Regions, Genetic, pubmed-meshheading:10639363-Sequence Homology, Nucleic Acid, pubmed-meshheading:10639363-beta-Lactamases
pubmed:year
2000
pubmed:articleTitle
High-level expression of chromosomally encoded SHV-1 beta-lactamase and an outer membrane protein change confer resistance to ceftazidime and piperacillin-tazobactam in a clinical isolate of Klebsiella pneumoniae.
pubmed:affiliation
Medical Service, Department of Veterans Affairs Medical Center, Cleveland, OH 44106, USA. louis.rice@med.va.gov
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S.