FIG. 1.
Chromosomal region surrounding the X. fastidiosa type II R-M system. The orientations and locations of the putative open reading frames (ORFs; arrows) and tRNAAsn (triangle) are indicated. The PD1608 gene is predicted to encode a subtype P type II REase; the PD1607 gene is predicted to encode a subtype gamma type II MTase (REBASE) (25). The PD1608-PD1607 operon is located within prophage-like region Xpd8 (4) and adjacent to tRNAAsn. The PD1605 ORF contains a frameshift mutation, which disrupts the putative integrase of Xpd8 (4). PD1606 extends toward and overlaps the 3′ end of PD1607 by 143 bp. The hypothetical protein encoded by the PD1606 gene shows some similarity in its N terminus (4e-10) to proteins belonging to the bacteriophage P4-like integrase subfamily (cd00801 sequence cluster) (19). However, PD1606 does not resemble PD1605 or other X. fastidiosa integrases.