Heterogeneity of heat-resistant proteases from milk Pseudomonas species.

摘要: Pseudomonas fragi, lundensis and members of the fluorescens group may spoil Ultra High Temperature (UHT) treated milk dairy products, due to production heat-stable proteases in cold chain raw milk. Since aprX gene codes for a heat-resistant protease P. fluorescens, presence this has also been investigated other genus. For purpose an aprX-screening PCR test developed. Twenty-nine representatives important species thirty-five reference strains were screened. In 42 out 55 strains, was detected, which proves potential aprX-PCR as screening tool potentially proteolytic samples. An extensive study obtained aprX-sequences on DNA amino acid level, however, revealed large heterogeneity within isolates. Although sets limitations general detection method all milk, it offers great development multiplex targeting individual aprX-genes. Furthermore, our data illustrated use taxonomic marker, help resolving current deadlock group.