title: Characterization of a novel cryptic plasmid, pHLHK26, in Laribacter hongkongensis.
abstract: We report the complete nucleotide sequence and characterization of a cryptic plasmid, pHLHK26, recovered from a strain of Laribacter hongkongensis isolated from a patient with community acquired gastroenteritis. pHLHK26 consists of 8700 bp, with G + C content 51.3%. The copy number (mean +/- SD) is 0.57 +/- 0.07 and it is stable after four passages (about 240 generations) in the absence of selection. There is a predicted origin of replication that consists of a DnaA box and five 22-bp direct repeats. pHLHK26 has four ORFs with two genes encoded in the sense direction and the other two in antisense direction. These four ORFs encode a putative plasmid partitioning protein of the ParA family, a putative protein that contains putative ADP-ribose 1"-phosphatase activity belonging to the Appr-1-p processing enzyme family, a putative recombinase (TniR) of the resolvase/invertase family, and a putative replication protein, respectively. We speculate that pHLHK26 is a theta, possibly Class A, replicative plasmid, as it contains an origin of replication with AT-rich region, a number of iterons and a DnaA box and a gene that encodes a replicative protein most homologous to those of other theta replicative plasmids and it shares eight of the nine positions of the consensus sequence TTAT(C/A)CA(C/A)A (TTTTCCACA in pHLHK26) in the DnaA boxes observed in other classical examples of Class A plasmids of this group.
authors.affiliation: Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong.
authors.forename: Patrick C Y
authors.initials: PC
authors.lastname: Woo
authors.forename: Jade L L
authors.initials: JL
authors.lastname: Teng
authors.forename: Shirley S L
authors.initials: SS
authors.lastname: Ma
authors.forename: Susanna K P
authors.initials: SK
authors.lastname: Lau
authors.forename: Kwok-Yung
authors.initials: KY
authors.lastname: Yuen
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D001482:Base Composition; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D017714:Community-Acquired Infections / Q000382:microbiology; D016384:Consensus Sequence; D004265:DNA Helicases / Q000235:genetics; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D005759:Gastroenteritis / Q000382:microbiology; D006801:Humans; D008969:Molecular Sequence Data; D009346:Neisseriaceae / Q000235:genetics* / Q000302:isolation & purification; D016366:Open Reading Frames; D010744:Phosphoric Monoester Hydrolases / Q000235:genetics; D010802:Phylogeny; D010957:Plasmids / Q000235:genetics*; D045522:Recombinases / Q000235:genetics; D018741:Replication Origin / Q000235:genetics; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D015534:Trans-Activators / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; C066312:DnaA protein, Bacteria; D045522:Recombinases; D015534:Trans-Activators; C052883:chromosome partition proteins, bacterial; C045264:replication initiator protein; D010744:Phosphoric Monoester Hydrolases; D004265:DNA Helicases