Department of Microbiology, Chonnam National University Medical School, Gwangju, Republic of Korea.
J Microbiol. 2010 Oct;48(5):663-7. doi: 10.1007/s12275-010-9268-9. Epub 2010 Nov 3.
Cytolysin A (ClyA) is a pore-forming hemolytic protein encoded by the clyA gene. It has been identified in Salmonella enterica serovars Typhi and Paratyphi A. To identify and characterize the clyA genes in various Salmonella enterica strains, 21 different serotypes of strains isolated from clinical specimens were presently examined. Full-length clyA genes were found in S. enterica serovar Brandenburg, Indiana, Panama, and Schwarzengrund strains by polymerase chain reaction amplification. The ClyA proteins from these four strains showed >97% amino acid identity to that of S. enterica serovar Typhi. Although all four serovars expressed detectable levels of ClyA as determined by Western blot analysis, they did not show a strong hemolytic effect on blood agar, indicating that ClyA may not be efficiently expressed or secreted. Escherichia coli transformed with clyA genes from the four serovars enhanced production of ClyA proteins and hemolytic activities to a level similar to S. enterica serovar Typhi ClyA. The present results suggest that ClyA may play a role in the pathogenesis of S. enterica serovar Brandenburg, Indiana, Panama and Schwarzengrund.
细胞溶素 A（ClyA）是一种由 clyA 基因编码的形成孔的溶血蛋白。它已在伤寒沙门氏菌血清型 Typhi 和 Paratyphi A 中被鉴定。为了鉴定和描述各种沙门氏菌菌株中的 clyA 基因，目前对 21 种从临床标本中分离的不同血清型菌株进行了检查。通过聚合酶链反应扩增，在肠炎沙门氏菌血清型 Brandenburg、Indiana、Panama 和 Schwarzengrund 菌株中发现了全长的 clyA 基因。这四个菌株的 ClyA 蛋白与伤寒沙门氏菌的氨基酸序列同源性>97%。尽管所有四个血清型在 Western blot 分析中均检测到 ClyA 的表达水平，但它们在血琼脂上并没有显示出强烈的溶血作用，表明 ClyA 可能没有得到有效表达或分泌。用来自四个血清型的 clyA 基因转化的大肠杆菌增强了 ClyA 蛋白和溶血活性的产生，使其水平与伤寒沙门氏菌血清型 Typhi ClyA 相似。目前的结果表明，ClyA 可能在肠炎沙门氏菌血清型 Brandenburg、Indiana、Panama 和 Schwarzengrund 的发病机制中发挥作用。
