Hancox L S, Yeh K S, Clegg S
Department of Microbiology, University of Iowa, College of Medicine, Iowa City 52242, USA.
FEMS Immunol Med Microbiol. 1997 Dec;19(4):289-96. doi: 10.1111/j.1574-695X.1997.tb01099.x.
Mutations in the fimH gene of Salmonella typhimurium result in a non-fimbriate, non-adhesive phenotype. This phenotype was shown to be due to the lack of both fimH and fimF expression since disruption of the fimH gene by insertion of a DNA cassette into this determinant results in mutants that are complemented by plasmids carrying both fimH and fimF. Deletion mutations within the S. typhimurium fimH gene carried on a recombinant plasmid can be used to complement the mutant, and these transformants are non-adhesive but fully fimbriate, consistent with the role of FimH as being necessary for fimbrial adhesin expression. Adherence to erythrocytes, HeLa, and Hep-2 cells is associated with expression of the FimH polypeptide, and fimbriate strains that cannot synthesize FimH are non-adhesive. Discrete differences in the amino acid sequences of the adhesive type 1 and the non-hemagglutinating type 2 FimH polypeptides were detected, and are most likely responsible for the differences in hemagglutinating activity.
鼠伤寒沙门氏菌fimH基因的突变会导致非菌毛、非黏附表型。这种表型被证明是由于fimH和fimF表达缺失所致，因为通过将DNA盒插入该决定簇来破坏fimH基因会产生可被携带fimH和fimF的质粒互补的突变体。携带在重组质粒上的鼠伤寒沙门氏菌fimH基因内的缺失突变可用于互补突变体，这些转化体不具有黏附性但菌毛完整，这与FimH作为菌毛黏附素表达所必需的作用一致。对红细胞、HeLa细胞和Hep - 2细胞的黏附与FimH多肽的表达相关，而不能合成FimH的菌毛菌株不具有黏附性。检测到1型黏附性和2型非血凝性FimH多肽的氨基酸序列存在明显差异，这很可能是血凝活性差异的原因。
