Description of a novel Mycobacterium simiae allelic variant isolated from Caribbean AIDS patients by PCR-restriction enzyme analysis and sequencing of hsp65 gene

A sudden upsurge in the isolation of Mycobacterium simiae from terminally i ll AIDS patients was recently reported on the Caribbean island of Guadeloup e. Identification of these M. simiae isolates was achieved using biochemica l tests and further confirmed by PCR-restriction analysis (PRA) of a 439-bp fragment of hsp65. A novel PRA profile III (three Bst EII fragments of 240 /125/80 bp and four HaeIII fragments of 145/125/40/25 bp) was observed in f our blood isolates from two patients. The 16S rRNA gene sequencing of the h ypervariable A region confirmed that all the pattern III isolates were inde ed M. simiae species, and the hsp65 sequencing confirmed the existence of a new hsp65 allele in these caribbean isolates. A hsp65 sequence-based phylo genetic tree was also created for 39 species including M. simiae and relate d mycobacterial species as well as other rapid and slow growing mycobacteri a, and may serve as an useful tool for identification of mycobacteria to sp ecies level. (C) 2000 Academic Press.