hrp基因是植物病原细菌中一类重要的致病基因,一般成簇排列。对14种已完成全基因组测序的植物病原细菌基因组中的hrp基因簇进行了大小、G+C含量、基因组成的BlastP比较。发现它们的大小在18～24 kb,由22～28个基因组成。欧文氏菌属和假单胞菌属的菌株中G+C含量较低,拉尔氏菌属和黄单胞菌属菌株的G+C含量较高。而且,各菌属的基因簇都有其独有的hrp基因,如假单胞菌属是hrpK1、hrpV、hrpA|欧文氏菌属是hrpT、hrpV、hrpA|拉尔氏菌属是hrpZ、hrpX、hrpY、hrpV|黄单胞菌属是hrpE、hrpD6、hpaA。其中,基因hrpA1、hrpA、hrpY和hrpE在假单胞菌属、欧文氏菌属、拉尔氏菌属和黄单胞菌属中均编码Ⅲ型菌毛的基因,可能在寄主和病原物识别中起重要作用。
hrpgene is one of important pathogenitygenes in phytopathogenic bacteria,usually in cluster. The size,g+ C contents and BlastP of the constitutedgenes of 14 completed sequenced phytopathogenic bacterias in this article compare. It find that these size ofgene clusters among 18-24 kb,made up by 22-28genes. Theg+ C con-tents is lower in the Pseudomonas and Erwiniagenus,but higher in the Xanthomonas and Ralstoniagenus. Moreo-ver,everygenus has its own unique hrpgene cluster,such as in the Pseudomonas are hrpZ1,hrpA1,hrpVgenes. In the Erwiniagenus are hrpT,hrpV,hrpAgenes. In the Ralstoniagenus are hrpZ,hrpX,hrpY,hrpVgenes. In the Xan-thomonas are hrpE,hrpD6,hpaA. Among thesegenes,hrpA1,hrpA,hrpY,hrpE respectively belong to Pseudomonas spp,Erwinia spp,Ralstonia spp and Xanthomonas spp,encode type Ⅲ pilus,thesegenes maybe act as important function in pathogens recognize host progross.
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