Zainuddin Z F, Dale J W
Department of Microbiology, University of Surrey, Guildford, UK.
Tubercle. 1990 Mar;71(1):43-9. doi: 10.1016/0041-3879(90)90060-l.
Evidence of the presence of plasmids in Mycobacterium tuberculosis is lacking, whereas they are widespread in some other mycobacterial species. We examined, by agarose gel electrophoresis, a total of 197 clinical isolates of M. tuberculosis, mostly resistant to one or more antibiotics, and were able to detect bands of apparently extrachromosomal DNA at a low level in some isolates. These presumptive plasmids could not be isolated by CsCl/ethidium bromide gradient ultracentrifugation, and may consist of unusual forms of DNA. The possible existence of single stranded plasmid DNA is discussed.
在结核分枝杆菌中缺乏质粒存在的证据，而它们在其他一些分枝杆菌物种中广泛存在。我们通过琼脂糖凝胶电泳检查了总共197株结核分枝杆菌临床分离株，这些分离株大多对一种或多种抗生素耐药，并且能够在一些分离株中低水平检测到明显的染色体外DNA条带。这些推测的质粒不能通过氯化铯/溴化乙锭梯度超速离心分离，可能由不寻常形式的DNA组成。本文讨论了单链质粒DNA存在的可能性。
