Data from: The Rickettsia endosymbiont of Ixodes pacificus contains all the genes of de novo folate biosynthesis

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.