Kessler A C, Haase A, Reeves P R
Department of Microbiology, University of Sydney, New South Wales, Australia.
J Bacteriol. 1993 Mar;175(5):1412-22. doi: 10.1128/jb.175.5.1412-1422.1993.
Salmonella enterica and Yersinia pseudotuberculosis are the only examples in nature known to use a variety of 3,6-dideoxyhexose derivatives as O antigen constituents. To allow a comparison of the responsible biosynthetic genes of the two organisms, we have sequenced a section of the Y. pseudotuberculosis serogroup IIA rfb region that contained the genes for the abequose biosynthetic pathway. Comparison of the identified genes with the rfb region of S. enterica LT2 showed that the two dideoxyhexose pathway gene clusters are related. The arrangement of the genes was largely conserved, and the G + C compositions of the two DNA regions were strikingly similar; however, the degree of conservation of nucleotide and protein sequences suggested that the two gene clusters have been evolving independently for considerable time. Hybridization experiments showed that the dideoxyhexose pathway genes are widespread throughout the various serogroups of Y. pseudotuberculosis.
肠炎沙门氏菌和假结核耶尔森氏菌是自然界中已知仅有的使用多种3,6-二脱氧己糖衍生物作为O抗原成分的例子。为了比较这两种生物的相关生物合成基因，我们对假结核耶尔森氏菌血清群IIA的rfb区域的一部分进行了测序，该区域包含阿比可糖生物合成途径的基因。将鉴定出的基因与肠炎沙门氏菌LT2的rfb区域进行比较，结果表明这两个二脱氧己糖途径基因簇是相关的。基因的排列在很大程度上是保守的，并且两个DNA区域的G + C组成非常相似；然而，核苷酸和蛋白质序列的保守程度表明这两个基因簇已经独立进化了相当长的时间。杂交实验表明，二脱氧己糖途径基因广泛分布于假结核耶尔森氏菌的各个血清群中。
