Generation and characterization of monoclonal antibodies against Staphylococcus aureus thermonuclease.
Monoclonal antibodies (MAbs) against Staphylococcus aureus thermonuclease (TN) were raised by immunizing BALB/c mice with a commercial TN preparation. Six monoclones were generated producing MAbs specific for S. aureus TN as tested in Western blots and ELISA. They all combined with a 17 kD and a 21 kD protein, respectively, both of which showed DNase activity. All MAbs were of IgG1 isotype with kappa light chain. Competition ELISA showed that five of the MAbs recognized a total of three different binding sites of TN, designated I, II and III, respectively. Only the anti-site II MAbs inhibited the DNase activity. A MAb-based sandwich ELISA showed a lower detection limit for TN of approximately 0.5 ng/ml protein. Only S. aureus strains (culture supernatants) showed positive ELISA (31 positive/31 tested), although other tested gram positive cocci produced thermostable nucleases. The MAbs have potentials as reagents for rapid and specific detection of S. aureus.
Brakstad
O G
OG
Department of Microbiology, Faculty of Medicine, University of Trondheim, Norway.
Maeland
J A
JA
D000818:Animals; D000911:Antibodies, Monoclonal / Q000096:biosynthesis* / Q000276:immunology; D001665:Binding Sites; D004797:Enzyme-Linked Immunosorbent Assay; D051379:Mice; D008807:Mice, Inbred BALB C; D008836:Micrococcal Nuclease / Q000032:analysis / Q000276:immunology*; D011817:Rabbits; D013211:Staphylococcus aureus / Q000201:enzymology*
D000911:Antibodies, Monoclonal; D008836:Micrococcal Nuclease