Severina E, Ramirez M, Tomasz A
The Rockefeller University, New York, New York 10021, USA.
J Clin Microbiol. 1999 Oct;37(10):3308-15. doi: 10.1128/JCM.37.10.3308-3315.1999.
The great majority of clinical isolates of Streptococcus pneumoniae carry prophages that may be identified through their hybridization with a DNA probe specific for the pneumococcal lytA gene (M. Ramirez, E. Severina, and A. Tomasz, J. Bacteriol. 181:3618-3625, 1999). We now show that the lytA hybridization pattern of chromosomal SmaI digests is stable for a given strain during extensive serial culturing in the laboratory; the pattern is specific for the strain's clonal type, as defined by pulsed-field gel electrophoretis (PFGE) pattern, and variations in PFGE subtypes may be explained by changes in the number and chromosomal localization of this prophage(s). These observations indicate that the lytA hybridization pattern may be used as a molecular epidemiological marker that offers additional resolution of the genetic background of S. pneumoniae strains.
绝大多数肺炎链球菌临床分离株携带原噬菌体，可通过它们与针对肺炎球菌lytA基因的DNA探针杂交来鉴定（M. 拉米雷斯、E. 塞韦里娜和A. 托马兹，《细菌学杂志》181:3618 - 3625，1999年）。我们现在表明，在实验室进行广泛的连续传代培养期间，染色体SmaI酶切片段的lytA杂交模式对于给定菌株是稳定的；该模式对于菌株的克隆类型具有特异性，如通过脉冲场凝胶电泳（PFGE）模式所定义的，并且PFGE亚型的变化可以通过这种原噬菌体的数量和染色体定位的改变来解释。这些观察结果表明，lytA杂交模式可作为一种分子流行病学标记，为肺炎链球菌菌株的遗传背景提供额外的分辨率。
