Hughes C V, Andersen R N, Kolenbrander P E
Laboratory of Microbial Ecology, National Institute of Dental Research, Bethesda, Maryland 20892.
Infect Immun. 1992 Mar;60(3):1178-86. doi: 10.1128/iai.60.3.1178-1186.1992.
The gram-negative human oral bacterium Veillonella atypica PK1910 exhibits both lactose-inhibitable and lactose-noninhibitable coaggregations with certain human oral streptococci. A mild sonication procedure was used to obtain a veillonella surface protein preparation against which antisera were prepared. To characterize the lactose-inhibitable coaggregation, coaggregation-defective (COG-) mutants unable to exhibit this kind of coaggregation (class 1 mutants) were used to absorb the antisera. Only the lactose-inhibitable coaggregations were blocked by these absorbed antisera. The absorbed antiserum also reacted with a 45-kDa protein found in the parent and in class 2 COG- mutants that exhibited lactose-inhibitable coaggregation. This protein was not detected in surface protein preparations of class 1 COG- mutants. Two affinity protocols, involving agarose-lactose beads and the streptococcal coaggregation partner cells, were used to bind surface proteins from V. atypica PK1910. In each protocol, the 45-kDa protein was eluted by a solution containing 100 mM lactose. Antiserum was prepared against agarose-lactose beads with bound 45-kDa protein. When absorbed with class 1 COG- mutants, the antiserum blocked lactose-inhibitable coaggregation and reacted with the 45-kDa protein in immunoblots. When the same antiserum was absorbed with class 2 COG- mutant cells, it lost both properties, suggesting that the 45-kDa protein is an adhesin that mediates coaggregation with streptococci. The proposed adhesin does not seem to be the structural subunit of veillonella fimbriae, since no differences in fimbriae were observed by electron microscopy of the parent and all three classes of mutants.
革兰氏阴性人类口腔细菌非典型韦荣球菌PK1910与某些人类口腔链球菌表现出乳糖抑制性和乳糖非抑制性共聚。采用温和的超声处理程序获得韦荣球菌表面蛋白制剂，并制备了抗血清。为了表征乳糖抑制性共聚，使用无法表现出这种共聚的共聚缺陷（COG-）突变体（1类突变体）吸收抗血清。只有乳糖抑制性共聚被这些吸收的抗血清阻断。吸收后的抗血清还与亲本和表现出乳糖抑制性共聚的2类COG-突变体中发现的一种45 kDa蛋白发生反应。在1类COG-突变体的表面蛋白制剂中未检测到这种蛋白。使用两种亲和方法，涉及琼脂糖-乳糖珠和链球菌共聚伙伴细胞，来结合非典型韦荣球菌PK1910的表面蛋白。在每个方法中，45 kDa蛋白都被含有100 mM乳糖的溶液洗脱。制备了针对结合有45 kDa蛋白的琼脂糖-乳糖珠的抗血清。当用1类COG-突变体吸收时，该抗血清阻断乳糖抑制性共聚，并在免疫印迹中与45 kDa蛋白发生反应。当用2类COG-突变体细胞吸收相同的抗血清时，它失去了这两种特性，这表明45 kDa蛋白是一种介导与链球菌共聚的粘附素。所提出的粘附素似乎不是韦荣球菌菌毛的结构亚基，因为通过电子显微镜观察亲本和所有三类突变体的菌毛没有发现差异。
