钩端螺旋体轴丝的分离纯化和SDS-PAGE分析

PURIFICATION:AND SDS-PAGE ANALYSIS OF AXIAL FILAMENTS FROM LEPTOSPIRES

作者应用差速离心和蔗糖密度梯度离心法,分离纯化了钩端螺旋体(钩体)轴丝,并在电镜下观察其超微结构。用SDS-PAGE分析了轴丝蛋白组成和分子量。比较了三株不同毒力、不同种属钩体的轴丝蛋白。结果显示轴丝由6～7种蛋白质构成,分子量为26～80kd,三株钩体都有分子量为31.5kd的蛋白质。讨论了轴丝在钩体分类及钧体病诊断中应用的可能性。

A modified method, differential centri-fugation followed by sucrose density centri-fugation, was used to purify axial filamentsfrom three strains of Leptospires. Ultra-structure of the axial filaments was studiedand profiles of the axial filaments werecharacterized and compared. The resultshave shown that all the three strains ofLeptospires, j. e., L. interrogsans serovarLai strain 017, L. biflexa serovar patocstrain Patoc I and L. illini strain 3055, havetwo axial filaments in one cell. The axialfilament is 20 nm in diameter. It is the firstobservation that the end which inserts thecytoplasms cylinder is wider in diameterthan the free one. An insertion pore struc-ture is observed. The new method yields1.5mg axial filaments from 12 g leptospirescells. SDS-PAGE was first employed in theanalysis of axial filaments of leptospires,The results have also shown that there are6 proteins in the axial filaments of strain017, MW 26 000-50 000 while 7 proteins inthe axial filaments of strain Patoc I andstrain 3055. MW 29 000-80 000 and 28 500-80 000 respectively. Interestingly, all the axialfilaments of the three strains have a com-mon protein band of MW 31 5000. Thepossibility of using axial filament proteinsas a new criterion for typing and a sero-diagnosis antigen is discussed.