嗜肺巴氏杆菌L型的诱导及其流行病学意义初探

Preliminary Study on the Induction of Pasteurella pneumotropica L-form and Its Implications in Epidemiology

目的 探讨L型嗜肺巴氏杆菌在诊断学及流行病学上的意义。方法青霉素液体法诱导，并对嗜肺巴氏杆菌L型的生物学特性进行系统观察。结果嗜肺巴氏杆菌L型具有典型的“煎蛋状”(L型)和“丝状”(F型)菌落，扫描电镜观察，L型菌体呈球状、杆状、长丝状：革兰染色呈阴性、缠绕的长丝体，并具有圆球体及巨型体，细胞壁染色显示细胞壁缺失：对紫外线、新洁尔灭抵抗力较原菌增强5-10倍；自然干燥环境中，原菌2d死亡，而L型可存活12d：能透过0．45lam滤膜；回复的最初几代，其菌体形态较原菌大数倍。结论L型嗜肺巴氏杆菌在形态学方面有较大变化，对理化因素及外界环境抵抗力增强，有可能透过胎盘屏障垂直传播。本研究提示L型嗜肺巴氏杆菌在该菌诊断学及流行病学上有重要意义。

Objective To study the significant importance of L-form of Pasteurella pneumotropica in the diagnostics and epidemiology of P.pneumotropica. Methods The biological characteristics of L-form of Pasteurella pneumotropica induced with the penicillin G were observed Results Two types of L-form of Pasteurella pneumotropica were found, that is, filamentous (F) type and fried-egg (L) type, it was found that L form had polymorphism including long filamentous bodies, round bodies and rod bodies under scanning electron microscope. It was gram negative bacteria with many filamentous bodies coiled together, and also a small amount of spherical and giant bodies were observed. Cell wall deficiency was found by cell wall staining. Its resistance to ultraviolet and Benzalkonium bromide was increased..In natural dry conditions, L-form could live 12 days whereas parent form only 2 days. L-form could pass through the filter of 0.45μm-pore-size. When returned to parent form, the body was larger than original parent form. Conclusion There are many differences in morphology between L-form and parent form. L-form has much resistance to physical and chemical factors. It could permeate the placenta barrier, and may result in vertical transmission to the fetal mice. Our findings suggest that L-form of P.pneumotropica is of significant importance in the diagnostics and epidemiology of P.pneumotropica.