title: Detection and diversity of a putative novel heterogeneous polymorphic proline-glycine repeat (Pgr) protein in the footrot pathogen Dichelobacter nodosus.
abstract: Dichelobacter nodosus, a Gram-negative anaerobic bacterium, is the essential causative agent of footrot in sheep. Currently, depending on the clinical presentation in the field, footrot is described as benign or virulent; D. nodosus strains have also been classified as benign or virulent, but this designation is not always consistent with clinical disease. The aim of this study was to determine the diversity of the pgr gene, which encodes a putative proline-glycine repeat protein (Pgr). The pgr gene was present in all 100 isolates of D. nodosus that were examined and, based on sequence analysis had two variants, pgrA and pgrB. In pgrA, there were two coding tandem repeat regions, R1 and R2: different strains had variable numbers of repeats within these regions. The R1 and R2 were absent from pgrB. Both variants were present in strains from Australia, Sweden and the UK, however, only pgrB was detected in isolates from Western Australia. The pgrA gene was detected in D. nodosus from tissue samples from two flocks in the UK with virulent footrot and only pgrB from a flock with no virulent or benign footrot for >10 years. Bioinformatic analysis of the putative PgrA protein indicated that it contained a collagen-like cell surface anchor motif. These results suggest that the pgr gene may be a useful molecular marker for epidemiological studies.
authors.affiliation: Department of Biological Sciences, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK. l.a.calvo-bado@warwick.ac.uk
authors.forename: Leo A
authors.initials: LA
authors.lastname: Calvo-Bado
authors.forename: Laura E
authors.initials: LE
authors.lastname: Green
authors.forename: Graham F
authors.initials: GF
authors.lastname: Medley
authors.forename: Atiya
authors.initials: A
authors.lastname: Ul-Hassan
authors.forename: Rose
authors.initials: R
authors.lastname: Grogono-Thomas
authors.forename: Nicky
authors.initials: N
authors.lastname: Buller
authors.forename: Jasmeet
authors.initials: J
authors.lastname: Kaler
authors.forename: Claire L
authors.initials: CL
authors.lastname: Russell
authors.forename: Ruth M
authors.initials: RM
authors.lastname: Kennan
authors.forename: Julian I
authors.initials: JI
authors.lastname: Rood
authors.forename: Elizabeth M H
authors.initials: EM
authors.lastname: Wellington
mesh_terms: D000818:Animals; D001315:Australia; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics*; D020376:Dichelobacter nodosus / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism*; D005535:Foot Rot / Q000382:microbiology; D014644:Genetic Variation; D005998:Glycine / Q000737:chemistry / Q000235:genetics; D018598:Minisatellite Repeats / Q000235:genetics; D008969:Molecular Sequence Data; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D011392:Proline / Q000737:chemistry / Q000235:genetics; D020449:Repetitive Sequences, Amino Acid / Q000235:genetics; D012756:Sheep; D012757:Sheep Diseases / Q000382:microbiology; D013548:Sweden; D006113:United Kingdom
chemical_list: D001426:Bacterial Proteins; D011392:Proline; D005998:Glycine