Genetic Analysis of Multiple Loci Suggests that Mutations in the Pneumocystis carinii f. sp. hominis Dihydropteroate Synthase Gene Arose Independently in Multiple Strains

AUTOR(ES)

Ma, Liang

FONTE

American Society for Microbiology

RESUMO

To determine if mutations in the dihydropteroate synthase (DHPS) gene of Pneumocystis carinii f. sp. hominis arose in a single strain that was subsequently widely disseminated, we examined four genomic regions of 22 P. carinii clinical isolates selected based on the absence or presence of mutations in the DHPS gene. By single-strand conformation polymorphism and DNA sequencing, we found varying genotypes for each of the four regions in isolates with DHPS mutations, suggesting that these mutations occurred independently in multiple strains of P. carinii. This suggests that exposure to sulfa will select for these mutations in diverse strains.

Documentos Relacionados

• Sequences of Pneumocystis carinii f. sp. hominis strains associated with recurrent pneumonia vary at multiple loci.
• Relationship between Mutations in Dihydropteroate Synthase of Pneumocystis carinii f. sp. hominis Isolates in Japan and Resistance to Sulfonamide Therapy
• DNA sequences identical to Pneumocystis carinii f. sp. carinii and Pneumocystis carinii f. sp. hominis in samples of air spora.
• Potential Coinfections Complicate Typing of Pneumocystis carinii f. sp. hominis
• Identification of Pneumocystis carinii f. sp. hominis Gene Sequences in Filtered Air in Hospital Environments