Use of murine myeloma protein M467 for detecting Salmonella spp. in milk.
This investigation introduces the use of an immunoglobulin A mouse myeloma protein for the detection of Salmonella spp. in milk. The immunoglobulin A protein M467 reacts with flagellin from a wide variety of serotypes. Two assays were developed which used an enzyme-linked immunosorbent assay (ELISA) and M467. Alkaline phosphatase was conjugated to M467 (M467-PH), and the presence of Salmonella dublin was detected by a competitive solid-phase ELISA and a membrane filtration ELISA. The competitive assay competed viable Salmonella spp. found in contaminated milk against polymerized flagellin or whole bacteria fixed to polyvinyl plates for binding by M467-PH. The membrane filtration method utilized a hydrophilic membrane for filtering the bacteria, which were then detected by the reaction with M467-PH and substrate. The sensitivity of the competitive solid-phase ELISA was 10(3) bacteria ml-1, whereas the filter membrane assay required the media containing the bacteria to be cultured in enrichment medium for 4 h before the assay to ensure detection. Either assay could be run within a typical 8-h work day. The filter membrane assay was not suitable for milk due to the high level of natural alkaline phosphatase activity in the liquid food.
D000818:Animals; D000942:Antigens, Bacterial / Q000302:isolation & purification; D002417:Cattle; D004797:Enzyme-Linked Immunosorbent Assay; D005407:Flagella / Q000276:immunology; D005516:Food Microbiology; D051379:Mice; D008892:Milk / Q000382:microbiology*; D009194:Myeloma Proteins / Q000276:immunology*; D012475:Salmonella / Q000276:immunology / Q000302:isolation & purification*
D000942:Antigens, Bacterial; D009194:Myeloma Proteins; C020957:myeloma protein M 467