A Simple Method for Detection of Staphylococcus aureus Using Anti-Protein A IgY

Abstract

Egg yolk immunogloblins (IgY) which react specifically with staphylococcal protein A were studied to assess their suitability for use in an enzyme-linked immunosorbent assay (ELISA). The ELISA was positive for all 31 Staphylococcus aureus strains and was negative for 47 out of 49 (96%) other staphylococcal species. The ELISA was also performed for the detection of protein A added to homogenates of a rice ball and a cake, and these homogenates showed little inhibitory effect on the ELISA. The detection limits of the ELISA for enrichment cultures of S. aureus SA106 in artificially contaminated rice ball and cake were 7.6×10²cfu/g and 5.5cfu/g, respectively. The ELISA test using anti-protein A IgY was found to be a simple method for detecting S. aureus.