The Rickettsia Endosymbiont of Ixodes pacificus Contains All the Genes of De Novo Folate Biosynthesis.
The Rickettsia Endosymbiont of Ixodes pacificus Contains All the Genes of De Novo Folate Biosynthesis.
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DOI：
10.1371/journal.pone.0144552
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发表时间：
2015
期刊：
影响因子：
3.7
通讯作者：
Zhong J
中科院分区：
文献类型：
--
作者：
Hunter DJ;Torkelson JL;Bodnar J;Mortazavi B;Laurent T;Deason J;Thephavongsa K;Zhong J
蜱和其他节肢动物通常是提供营养的细菌内共生体的宿主，这些细菌内共生体通过提供维生素和氨基酸等营养物质来促进宿主的健康。我们实验室已检测到太平洋硬蜱是立克次氏体种系统型G 021的宿主。这种内共生体主要存在于I.太平洋。研究G 021型转基因水稻在水稻中的作用。太平洋，生物信息学和分子方法进行。MUMmer全基因组序列比对。scapularis，与I. pacificus的全基因组序列进行比较。bellii OSU85-389、R. conorii，和R. felis等鉴定了8，190个与NCBI Trace Archive中的立克次体序列同源的独特序列。MetaCyc代谢重建显示，从头叶酸生物合成所需的所有叶酸基因直系同源物（folA、folC、folE、folKP、ptpS）存在于I.肩胛肌目的：研究G 021在I. pacificus中，使用简并引物PCR扩增细菌的叶酸生物合成途径的基因。经BLAST检索，folA、folC、folE、folKP和ptpS基因与布氏立克次体相应基因的核苷酸序列同源性分别为98.6%、98.8%、98.9%、98.5%和99.0%。系统进化树的构建表明，G 021型立克次体的叶酸基因与其它立克次体的同源基因是单系的。这项研究表明，所有的叶酸基因存在于立克次体属G 021型的基因组中，并且该细菌具有从头合成叶酸的遗传能力。
Ticks and other arthropods often are hosts to nutrient providing bacterial endosymbionts, which contribute to their host’s fitness by supplying nutrients such as vitamins and amino acids. It has been detected, in our lab, that Ixodes pacificus is host to Rickettsia species phylotype G021. This endosymbiont is predominantly present, and 100% maternally transmitted in I. pacificus. To study roles of phylotype G021 in I. pacificus, bioinformatic and molecular approaches were carried out. MUMmer genome alignments of whole genome sequence of I. scapularis, a close relative to I. pacificus, against completely sequenced genomes of R. bellii OSU85-389, R. conorii, and R. felis, identified 8,190 unique sequences that are homologous to Rickettsia sequences in the NCBI Trace Archive. MetaCyc metabolic reconstructions revealed that all folate gene orthologues (folA, folC, folE, folKP, ptpS) required for de novo folate biosynthesis are present in the genome of Rickettsia buchneri in I. scapularis. To examine the metabolic capability of phylotype G021 in I. pacificus, genes of the folate biosynthesis pathway of the bacterium were PCR amplified using degenerate primers. BLAST searches identified that nucleotide sequences of the folA, folC, folE, folKP, and ptpS genes possess 98.6%, 98.8%, 98.9%, 98.5% and 99.0% identity respectively to the corresponding genes of Rickettsia buchneri. Phylogenetic tree constructions show that the folate genes of phylotype G021 and homologous genes from various Rickettsia species are monophyletic. This study has shown that all folate genes exist in the genome of Rickettsia species phylotype G021 and that this bacterium has the genetic capability for de novo folate synthesis.