Lepper A W, Power B E
CSIRO Division of Animal Health, Animal Health Research Laboratory, Parkville, Victoria.
Aust Vet J. 1988 Oct;65(10):305-9. doi: 10.1111/j.1751-0813.1988.tb14512.x.
The degree of piliation of 29 haemolytic and 4 non-haemolytic Australian strains of Moraxella bovis representing 7 different pilus antigen groups was determined. The infectivity and virulence for the eye was measured in steroid-treated mice and in cattle. Non-piliated strains failed to infect the murine eye. Most moderately or heavily piliated strains reproducibly produced the highest infectivity and virulence scores in mice when compared with lightly or very lightly piliated strains (p less than 0.05). Non-haemolytic, piliated strains were infective and in one instance virulent for mice. Almost similar levels of infectivity and virulence were observed for 7 representative haemolytic strains tested in both cattle and mice. The relative molecular weight of pilin sub-units was compared using sodium dodecyl-sulphate polyacrylamide gel electrophoresis. Three classes of pili, alpha, beta and gamma of ascending sub-unit size were identified among the 7 pilus antigen serogroups. Pilin sub-unit size bore no relationship to the degree of piliation but most strains that were highly virulent in mice and cattle expressed alpha and gamma sub-units. Some strains appeared capable of switching from alpha to beta or form beta to gamma sub-unit production.
对代表7个不同菌毛抗原组的29株溶血性和4株非溶血性澳大利亚牛莫拉菌菌株的菌毛化程度进行了测定。在经类固醇处理的小鼠和牛中测量了其对眼睛的感染性和毒力。无菌毛菌株未能感染小鼠眼睛。与轻度或极轻度菌毛化菌株相比，大多数中度或重度菌毛化菌株在小鼠中可重复性地产生最高的感染性和毒力评分（p小于0.05）。非溶血性、菌毛化菌株具有感染性，在一个实例中对小鼠具有毒力。在牛和小鼠中测试的7株代表性溶血性菌株观察到几乎相似水平的感染性和毒力。使用十二烷基硫酸钠聚丙烯酰胺凝胶电泳比较菌毛蛋白亚基的相对分子量。在7个菌毛抗原血清群中鉴定出三类菌毛，α、β和γ，亚基大小依次递增。菌毛蛋白亚基大小与菌毛化程度无关，但在小鼠和牛中具有高毒力的大多数菌株表达α和γ亚基。一些菌株似乎能够从α亚基转换为β亚基或从β亚基转换为γ亚基产生。
