Investigation of pathogenic Streptococci species in local and imported mozzarella soft cheese in Baghdad city

Moutaz A.W Abdul Mounam, Nagham Mohammed Al-Gburi, Basil R.F. Razook


Background: The present work investigated the profile and biodiversity of the pathogenic streptococci species isolated from local and imported mozzarella soft cheese in Baghdad City from October 2022 to January 2023. The study aimed to examine the molecular characterization of 16Sr RNA gene in some streptococcus species isolates from mozzarella soft cheese in Baghdad city

Methods: From 50 samples, 8 isolates in all were found and identified based on the VITEK, molecular, and sequencing of the 16SrRNA gene. The eight isolates represented Lactococcus cremoris. Streptococcus alactolyticus, Streptococcus sanguinis, and Streptococcus thoraltensis. The isolates were subjected to conventional PCR and electrophoresis to detect the 16SrRNA gene using specific primers , Streptococcal genes were used in the neighbor-joining phylogenetic analysis that determined these sequences were derived from Streptococcal genes.

Results: DNA sequencing evaluation Significant alignments (96-99% identities) to the Streptococci isolates found in BLAST-NCBI Gene-bank were discovered after sequencing the bacterial DNA products generated by PCR. The results revealed that 8/50 amplified the 16SrRNA gene, which has a molecular weight of about 1250 bp. the gene distribution was statistically significant (p ≤ 0.05).

Conclusion: Streptococcus isolates from mozzarella soft cheese by using molecular tools to first stop the spread of the epidemic of harmful microorganisms in food, it is represented a health risk for the consumers.

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