Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2007-3-1
pubmed:abstractText
This study investigated the mechanisms of multidrug resistance (MDR) in an isolate of Bacteroides fragilis (WI1) from a patient with anaerobic sepsis. The MDR of WI1 affected susceptibility to beta-lactams, clindamycin, fluoroquinolones, metronidazole and tetracycline. In addition to its 5.31-Mb chromosome, WI1 possessed two low-copy-number plasmids, pHagl (5.6 kb) and pHag2 (9.9 kb), that were absent from B. fragilis NCTC 9343. Restriction digestion with EcoRV, HindIII and SstI, combined with DNA sequencing, revealed that pHAG2 contained a tet(Q) gene at base position 3689 that resided on the conjugative transposon CTn341. Genes cfiA (encoding a metallo-beta-lactamase) and erm(F) (encoding a macrolide-lincosamide-streptogramin B resistance determinant) were also found in WI1, but were absent from B. fragilis NCTC 9343. Nitrocefin hydrolysis revealed that WI1 had high beta-lactamase activity. Sequencing of the gyrA quinolone resistance-determining region revealed a mutation causing a Ser82 --> Phe substitution, and comparative quantitative real-time RT-PCR revealed that the cfiA, erm(F) and tet(Q) genes were all expressed in WI1. In addition, the resistance-nodulation-division efflux pump genes bmeB9 and bmeB15 were significantly over-expressed (12.30 +/- 0.42-fold and 3541.1 +/- 95.4-fold, respectively), and the efflux pump inhibitors carbonyl cyanide m-chlorophenylhydrazone and reserpine significantly increased the susceptibility of the isolate to several unrelated antibiotics (p <0.005). These data suggested that WI1 was highly multidrug-resistant because of the additive effects of chromosome- and plasmid-encoded resistance determinants.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
1198-743X
pubmed:author
pubmed:issnType
Print
pubmed:volume
13
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
183-9
pubmed:meshHeading
pubmed-meshheading:17328731-Amino Acid Substitution, pubmed-meshheading:17328731-Anti-Bacterial Agents, pubmed-meshheading:17328731-Anti-Infective Agents, pubmed-meshheading:17328731-Bacteroides Infections, pubmed-meshheading:17328731-Bacteroides fragilis, pubmed-meshheading:17328731-Chromosomes, Bacterial, pubmed-meshheading:17328731-Clindamycin, pubmed-meshheading:17328731-DNA, Bacterial, pubmed-meshheading:17328731-DNA Transposable Elements, pubmed-meshheading:17328731-Drug Resistance, Multiple, Bacterial, pubmed-meshheading:17328731-Fluoroquinolones, pubmed-meshheading:17328731-Genes, Bacterial, pubmed-meshheading:17328731-Humans, pubmed-meshheading:17328731-Metronidazole, pubmed-meshheading:17328731-Microbial Sensitivity Tests, pubmed-meshheading:17328731-Phenylalanine, pubmed-meshheading:17328731-Plasmids, pubmed-meshheading:17328731-Sequence Analysis, DNA, pubmed-meshheading:17328731-Tetracycline, pubmed-meshheading:17328731-beta-Lactamases
pubmed:year
2007
pubmed:articleTitle
Genetic analysis of mechanisms of multidrug resistance in a clinical isolate of Bacteroides fragilis.
pubmed:affiliation
Greater Los Angeles Veterans Administration Healthcare Systems, Los Angeles, CA, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't