title: Presence of glutamine at position 74 of pocket 4 in the BoLA-DR antigen binding groove is associated with occurrence of clinical mastitis caused by Staphylococcus species.
abstract: Potential relationships between amino acid motifs in the antigen binding groove of various alleles of the bovine major histocompatibility complex DR (BoLA-DR) molecule and occurrence of clinical mastitis caused by Staphylococcus species (non-Staphylococcus aureus) were investigated in a case-control study. A significant association (P< or =0.05) was detected between the presence of glutamic acid at position beta 74 and occurrence of mastitis caused by Staphylococcus spp. with a relative risk of 11. This motif is present in BoLA-DRB3.2*22, *23 and *24 alleles. Presence of a positively charged residue (arginine or lysine) at position 13 also showed a tendency (P< o r=0.1) towards an association with a higher risk of clinical mastitis caused by the same bacteria. This motif is present in BoLA-DRB3.2*23 and *8 alleles. Similarly, presence of arginine at position beta 71 (present in alleles *23 and *22) was associated with occurrence of this disease. These positions (beta 13, beta 71 and beta 74) form pocket 4 of the antigen binding groove, which plays an instrumental role in antigen binding and recognition by T-lymphocytes. Thus, it can be concluded that pocket 4 of the BoLA-DR molecule is involved in conferring susceptibility to clinical mastitis caused by Staphylococcus spp.
authors.affiliation: Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada N1G 2W1.
authors.forename: S
authors.initials: S
authors.lastname: Sharif
authors.forename: B A
authors.initials: BA
authors.lastname: Mallard
authors.forename: J M
authors.initials: JM
authors.lastname: Sargeant
mesh_terms: D000483:Alleles; D020816:Amino Acid Motifs / Q000235:genetics / Q000276:immunology; D000818:Animals; D016022:Case-Control Studies; D002417:Cattle; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D005260:Female; D000949:Histocompatibility Antigens Class II / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D008414:Mastitis, Bovine / Q000276:immunology* / Q000378:metabolism / Q000382:microbiology; D016133:Polymerase Chain Reaction / Q000662:veterinary; D012150:Polymorphism, Restriction Fragment Length; D017422:Sequence Analysis, DNA; D013203:Staphylococcal Infections / Q000276:immunology / Q000382:microbiology / Q000662:veterinary*; D013210:Staphylococcus / Q000276:immunology*
chemical_list: C423282:BoLA-DRB3 antigen; D018076:DNA, Complementary; D000949:Histocompatibility Antigens Class II