Baratéla K C, Saridakis H O, Gaziri L C, Pelayo J S
Departamento de Microbiologia, Universidade Estadual de Londrina, Brazil.
J Appl Microbiol. 2001 Mar;90(3):482-7. doi: 10.1046/j.1365-2672.2001.01270.x.
The effects of medium composition, calcium, iron and oxygen tension on the haemolytic activity of Plesiomonas shigelloides were investigated.
The haemolytic activity of seven strains of Ple. shigelloides was tested on the surface of Luria Agar (LA), Brain Heart Infusion Agar (BHIA) and Trypitic Soy Agar (TSA) containing 5% (v/v) sheep blood, and in the Agar Overlay (AO) assay. All strains produced beta-haemolysis in the AO assay in three media, and on the surface of LA. The kinetics of growth and haemolytic activity of Ple. shigelloides 9P3-1 were evaluated in six different media, and the highest production of haemolysin occurred in Luria Broth (LB). The haemolytic activity of 9P3-1 was stimulated by Ca2+ and inhibited by EDTA. Addition of iron to the culture medium did not affect bacterial growth, although it reduced bacterial haemolytic activity. In the presence of an iron chelator, growth of the 9P3-1 was inhibited, but its haemolytic activity was enhanced.
The haemolytic activity of Ple. shigelloides depends on medium composition, and that it is regulated by iron and is calcium-dependent.
These results show the importance of optimization of media composition and oxygen tension for detection of Ple. shigelloides haemolytic activity.
研究培养基成分、钙、铁和氧张力对类志贺邻单胞菌溶血活性的影响。
在含有5%（v/v）羊血的吕氏琼脂（LA）、脑心浸液琼脂（BHIA）和胰蛋白胨大豆琼脂（TSA）表面以及琼脂覆盖（AO）试验中，检测了7株类志贺邻单胞菌的溶血活性。所有菌株在三种培养基的AO试验中以及在LA表面均产生β溶血。在六种不同培养基中评估了类志贺邻单胞菌9P3-1的生长动力学和溶血活性，溶血素产量最高出现在吕氏肉汤（LB）中。9P3-1的溶血活性受Ca2+刺激，受EDTA抑制。向培养基中添加铁不影响细菌生长，但会降低细菌溶血活性。在存在铁螯合剂的情况下，9P3-1的生长受到抑制，但其溶血活性增强。
类志贺邻单胞菌的溶血活性取决于培养基成分，且受铁调节并依赖于钙。
这些结果表明优化培养基成分和氧张力对检测类志贺邻单胞菌溶血活性的重要性。
