Goh K S, Legrand E, Sola C, Rastogi N
Unité de la Tuberculose et des Mycobactéries, Institut Pasteur de Guadeloupe, BP 484, F-97165 Pointe-à-Pitre Cedex, Guadeloupe.
J Clin Microbiol. 2001 Oct;39(10):3705-8. doi: 10.1128/JCM.39.10.3705-3708.2001.
A total of 102 isolates of the Mycobacterium tuberculosis complex, including available "M. canettii" isolates, were studied by PCR-restriction analysis of a 441-bp fragment of the hsp65 gene. PRA upon HhaI enzyme digestion (GCGC) allowed easy differentiation of "M. canettii" from other members of the M. tuberculosis complex (three bands of 260, 105, and 60 bp for "M. canetti," compared to four bands of 185, 105, 75, and 60 bp for other members of the M. tuberculosis complex). Sequencing of the 441-bp hsp65 fragment of "M. canettii" isolates showed the disappearance of an HhaI site at position 235 due to a C-to-T transition that corresponded to position 631 of the homologous hsp65 gene of M. tuberculosis H37Rv. Considering that "M. canettii" may also exist as a stable rough morphotype, we suggest that the true number of "M. canettii" isolates may be underestimated in clinical microbiology laboratories.
对总共102株结核分枝杆菌复合群菌株,包括可得的“堪氏分枝杆菌”菌株,通过对hsp65基因441 bp片段进行PCR-限制性分析来研究。用HhaI酶(GCGC)消化后的PCR-限制性分析能够轻松区分“堪氏分枝杆菌”与结核分枝杆菌复合群的其他成员(“堪氏分枝杆菌”有260、105和60 bp三条带,而结核分枝杆菌复合群的其他成员有185、105、75和60 bp四条带)。对“堪氏分枝杆菌”菌株的441 bp hsp65片段进行测序显示,由于对应于结核分枝杆菌H37Rv同源hsp65基因第631位的C到T转换,第235位的HhaI位点消失。鉴于“堪氏分枝杆菌”也可能以稳定的粗糙形态型存在,我们认为临床微生物学实验室中“堪氏分枝杆菌”菌株的实际数量可能被低估。