High variation in pathogenicity of genetically closely related strains of Xanthomonas albilineans, the sugarcane leaf scald pathogen, in Guadeloupe
High variation in pathogenicity of genetically closely related strains of Xanthomonas albilineans, the sugarcane leaf scald pathogen, in Guadeloupe
复制标题
DOI：
10.1094/phyto-96-1081
复制
发表时间：
2006-10-01
期刊：
影响因子：
3.2
通讯作者：
Rott, P.
中科院分区：
文献类型：
--
作者：
Champoiseau, P.;Daugrois, J. -H.;Rott, P.
对瓜德罗普岛产的75株白色黄单胞菌进行了致病性鉴定。选取对叶片烫伤敏感的菌株B69566和19株具有代表性的菌株，根据茎定殖观察致病性的变化。这19株菌株的白孢霉素体外产量不同，但白孢霉素生物合成基因的限制性内切片段长度多态性模式相同。同样，脉冲场凝胶电泳也没有发现菌株之间的基因组变异。扩增片段长度多态性发现菌株间存在一定的变异，但这种变异与致病性差异无相关性。从瓜德罗普岛9株致病性不同的白胆螺旋体菌株的总基因组DNA中，聚合酶链反应仅扩增出与白胆螺旋体密切相关的40个致病基因中的3个（pilB、rpfA和xpsE）。这些基因的核苷酸序列在菌株间100%相同，并与这些基因和管家基因efp和ihfA进行系统发育研究表明，白胆弧菌是在X. campestris组和另一种维管植物病原体木杆菌（Xylella fastidiosa）之间的进化道路上进化的。白色黄单胞菌全基因组测序可能是破解白色白单胞菌致病性分子机制的下一步。
Pathogenicity of 75 strains of Xanthomonas albilineans from Guadeloupe was assessed by inoculation of sugarcane cv. B69566, which is susceptible to leaf scald, and 19 of the strains were selected as representative of the variation in pathogenicity observed based on stalk colonization. In vitro production of albicidin varied among these 19 strains, but the restriction fragment length polymorphism pattern of their albicidin biosynthesis genes was identical. Similarly, no genomic variation was found among strains by pulsed-field gel electrophoresis. Some variation among strains was found by amplified fragment length polymorphism, but no relationship between this genetic variation and variation in pathogenicity was found. Only 3 (pilB, rpfA, and xpsE) of 40 genes involved in pathogenicity of bacterial species closely related to X. albilineans could be amplified by polymerase chain reaction from total genomic DNA of all nine strains tested of X. albilineans differing in pathogenicity in Guadeloupe. Nucleotide sequences of these genes were 100% identical among strains, and a phylogenetic study with these genes and housekeeping genes efp and ihfA suggested that X. albilineans is on an evolutionary road between the X. campestris group and Xylella fastidiosa, another vascular plant pathogen. Sequencing of the complete genome of Xanthomonas albilineans could be the next step in deciphering molecular mechanisms involved in pathogenicity of X. albilineans.