鲍氏不动杆菌鳜鱼分离株的侵袭特性

Invasion of an Acinetobacter baumannii Train Isolated from Mandarin Fish

取从发病鳜鱼体内分离到的鲍氏不动杆菌 ( Acinetobacterbaumannii) MF1株 ,以 HEp-2细胞为指示细胞 ,用庆大霉素清洗裂解培养法和细胞超薄切片电镜观察 ,研究了 MF1株对 HEp-2细胞的侵袭力 ,同时用庆大霉素清洗裂解培养法比较了细菌在 4、1 0、2 8、37℃的侵袭力。结果显示 ,MF1株在 2 8、37℃时侵袭 HEp-2细胞 ,侵袭率达 0 .2 % ,细菌入胞后能增殖。MFl株在侵袭 HEp-2细胞 1 0～ 1 2 h时 ,胞内细菌数最多。电镜观察 ,可见胞内有内化的 MF1菌株。 MF1株在 4、1 0℃下不具侵袭力 。

Invasion of Acinetobacter baumannii strain MF1 isolated from diseased mandarin fish to cultured HEp 2 cells monolayer were evaluated by two methods, the electronic microscopy observation and the recovery of gentamincin resistant (Gm r) bacteria from Triton X 100 cell lysates. This strain was shown to be positive of invasion, meanwhile Gm r progeny recovered from MF1 infected cell monolayers which surpassed 0.2% amount of challenge inoculum. Intracellular growth of MF1 invasion demonstrated that the invaded bacteria could replicate in HEp 2 cells. With the maximum number of Gm r progeny to be obtained at 10 12 h postinfection. It indicated that MF1 invasion would be temperature dependent with it's invasive ability into HEp 2 cell being at 28℃ or 37℃, but not at 4℃ or 10℃. [WT5HZ]