Linked Life Data

11015384

Source:http://linkedlifedata.com/resource/pubmed/id/11015384

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
2000-11-1
pubmed:abstractText
Mycobacterium tuberculosis converts pyrazinamide to its active form by using the enzyme pyrazinamidase. This enzyme is coded for on the pncA gene, and mutations in the pncA gene result in absence of active enzyme, conferring resistance to the drug pyrazinamide. We investigated 27 strains of Mycobacterium tuberculosis suspected of being multidrug resistant. Each isolate was tested for susceptibility to pyrazinamide by the BACTEC 460TB method, and 19 were pyrazinamide resistant. The presence of active pyrazinamidase enzyme was sought by using the Wayne assay, which was positive in all of the sensitive isolates and four of the resistant isolates. The pncA gene was amplified by PCR, and mutations were sought by single-strand conformation polymorphism (SSCP) analysis. We identified four isolates which were phenotypically resistant to pyrazinamide, but which had active pyrazinamide enzyme on the Wayne assay and normal pncA gene SSCP. MICs measured by BACTEC 460TB and susceptibility testing at a lower pH of 5.5 confirmed genuine resistance. The pncA gene was sequenced in these four isolates and found not to have any mutations. This implies that an alternative mechanism of resistance exists in these strains. We conclude that genotypic assessment of pyrazinamide resistance is unreliable, because it depends on the identification of a single resistance mechanism. Phenotypic methods such as the BACTEC 460TB technique remain the best methods for pyrazinamide susceptibility testing.
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/11015384-10390239, http://linkedlifedata.com/resource/pubmed/commentcorrection/11015384-10411262, http://linkedlifedata.com/resource/pubmed/commentcorrection/11015384-10529902, http://linkedlifedata.com/resource/pubmed/commentcorrection/11015384-10973326, http://linkedlifedata.com/resource/pubmed/commentcorrection/11015384-13197751, http://linkedlifedata.com/resource/pubmed/commentcorrection/11015384-3142340, http://linkedlifedata.com/resource/pubmed/commentcorrection/11015384-3931319, http://linkedlifedata.com/resource/pubmed/commentcorrection/11015384-4203284, http://linkedlifedata.com/resource/pubmed/commentcorrection/11015384-4225184, http://linkedlifedata.com/resource/pubmed/commentcorrection/11015384-4964643, http://linkedlifedata.com/resource/pubmed/commentcorrection/11015384-4992754, http://linkedlifedata.com/resource/pubmed/commentcorrection/11015384-8095569, http://linkedlifedata.com/resource/pubmed/commentcorrection/11015384-8640557, http://linkedlifedata.com/resource/pubmed/commentcorrection/11015384-9055989, http://linkedlifedata.com/resource/pubmed/commentcorrection/11015384-9056006, http://linkedlifedata.com/resource/pubmed/commentcorrection/11015384-9196190
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0095-1137
pubmed:author
pubmed:issnType
Print
pubmed:volume
38
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3686-8
pubmed:dateRevised
2009-11-18
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Comparison of phenotypic and genotypic methods for pyrazinamide susceptibility testing with Mycobacterium tuberculosis.
pubmed:affiliation
Department of Medical Microbiology, Royal Free and University College Medical School, London, United Kingdom.
pubmed:publicationType
Journal Article, Comparative Study