Heat resistance and presence of genes encoding staphylococcal enterotoxins evaluated by multiplex-PCR of Staphylococcus aureus isolated from pasteurized camel milk.

Heat resistance and presence of genes encoding staphylococcal enterotoxins evaluated by multiplex-PCR of Staphylococcus aureus isolated from pasteurized camel milk. Biosci Rep. 2019 Nov 29;39(11): Authors: Yehia HM, Ismail EA, Hassan ZK, Al-Masoud AH, Al-Dagal MM Abstract Milk pasteurization eliminates vegetative pathogenic microorganisms and reduces microorganisms associated with spoilage. Camel milk is a well-accepted, traditionally consumed food in Arab countries. The present study aimed to investigate the microflora of pasteurized camel milk sold in Riyadh City, Saudi Arabia. The heat resistance of the microflora was tested in culture medium and lab-sterilized milk, and its composition was verified by multiplex polymerase chain reaction (PCR) using specific primers. Further verification was performed by using separate specific primers. The identified strain survived heat treatment at 65, 72, 80, 85, and 90°C for 30, 15, 10, 5, and 2 min, respectively. An unanticipated result was obtained when an enterotoxin producing strain of Staphylococcus aureus showed abnormal resistance to heat treatment. The enterotoxin gene within the PCR fragment was identified as enterotoxin C by DNA sequencing. During Basic Local Alignment Search Tool (BLAST) analysis, the isolated enterotoxin C genes showed >99% similarity to published database sequences of the Staphylococcus aureus strain SAI48 staphylococcal enterotoxin C variant v4 (sec) gene. T...
Source: Bioscience Reports - Category: Biomedical Science Authors: Tags: Biosci Rep Source Type: research