不同生长时期的金黄色葡萄球菌对重组人血小板型磷脂酶A_2的敏感性研究

Susceptibility of Staphylococcus Aureus at Different Growth Phase to the Recombinant Human Platelet Phospholipase A_2

目的:观察不同生长时期的金黄色葡萄球菌(简称金葡菌)对重组人血小板型磷脂酶A2(PLA2)杀菌作用的敏感性。方法:使用孵育培养和抗生素干预(红霉素预处理)2种方法来观察处于对数生长期或静止期的金葡菌对血小板型PLA2杀菌作用的敏感性,以只加入金葡菌者为空白对照,采用金葡菌存活率为指标评价杀菌作用。结果:血小板型PLA2对对数生长期金葡菌杀菌作用强于静止期金葡菌,120min时二者金葡菌存活率分别为1%、55%;经红霉素预处理后的对数生长期的金葡菌对血小板型PLA2的敏感性降低,120min时金葡菌存活率为63%,而未经红霉素预处理者为1%。结论:生长活跃期金葡菌较静止期金葡菌对血小板型PLA2的杀菌作用更敏感;红霉素可降低金葡菌对血小板型PLA2的敏感性。

OBJECTIVE： To study the susceptibility of Staphylococcus aureus（S.aureus） at different growth phase to recombinant human platelet phospholipase A2（PLA2） . METHODS： The susceptibility of S.aureus in logarithmic phase or silent phase to the recombinant human platelet PLA2 were observed through incubation culture and erythromycin pretreatment with nonetreated S.aureus as blank control. The bactericidal action was evaluated with the survival rate of S.aureus as index. RESULTS： The recombinant human platelet PLA2 showed stronger bactericidal activity against logarithmic phase S. aureus than silent phase S.aureus ; The survival rate at 120 min was 1% for logarithmic phase S. aureus and 55% for silent phase S. aureus. Erythromycin pretreatment reduces the susceptibility of logarithmic phase S. aureus to PLA2, and the sur- vival rate of which was 63% at 120 min, however, the survival rate of the untreated logarithmic phase S. aureus was 1%. CONCLUSIONS： As compared with the S. aureus in silent stage, the S. aureus in active growth stage are more susceptible to PLA2. Erythromycin can lower the susceptibility of S. aureus to PLA2.