Wassenaar T M, van der Zeijst B A, Ayling R, Newell D G
Department of Bacteriology, Institute of Infectious Diseases and Immunology, School of Veterinary Medicine, University of Utrecht, The Netherlands.
J Gen Microbiol. 1993 Jun;139 Pt 6:1171-5. doi: 10.1099/00221287-139-6-1171.
Campylobacter jejuni strain 81116 contains two flagellin genes, flaA and flaB. Wild-type (WT) bacteria express flaA only, but flaB can be expressed under certain conditions. We have determined the importance of flagella for colonization of the avian caecum, which appears to be the natural environment for these bacteria. Mutants in which flaA or flaB, or both had been inactivated, and motility variants, were investigated. Flagella are not a requisite for colonization, but mutants lacking both flagellin genes colonized less efficiently than WT. Inactivation of the flaB gene, which had no effect on bacterial motility, enhanced chicken caecal colonization 1000-fold compared to WT. A variant (SF-1) with flagella composed of flagellin A, but with poor motility, also colonized better than WT. Conversely, mutants with an inactivated flaA gene colonized 100- to 1000-fold less efficiently than WT, regardless of their motility conferred by truncated or full-length flagellin B flagella. These results suggest that the presence of flagellin A, rather than motility, is essential for optimal bacterial colonization of chicken caeca.
空肠弯曲杆菌81116菌株含有两个鞭毛蛋白基因，flaA和flaB。野生型（WT）细菌仅表达flaA，但在某些条件下flaB也可表达。我们已经确定了鞭毛对于鸟类盲肠定殖的重要性，盲肠似乎是这些细菌的自然生存环境。我们研究了flaA或flaB或两者均失活的突变体以及运动性变体。鞭毛并非定殖所必需，但缺乏两个鞭毛蛋白基因的突变体定殖效率低于野生型。flaB基因的失活对细菌运动性没有影响，但与野生型相比，其增强了鸡盲肠定殖能力达1000倍。一种变体（SF-1），其鞭毛由鞭毛蛋白A组成，但运动性较差，其定殖能力也比野生型更好。相反，flaA基因失活的突变体定殖效率比野生型低100至1000倍，无论其由截短的或全长鞭毛蛋白B鞭毛赋予的运动性如何。这些结果表明，鞭毛蛋白A的存在而非运动性，对于鸡盲肠中细菌的最佳定殖至关重要。
