Molecular detection of some virulence factors genes of salmonella spp. isolated from chicken’s products and human in Wasit province, Iraq

Abstract

A total of 300 samples (150 chicken products samples (eggs, livers and minced meat) from different local supermarkets and 150 human fecal samples from clinical cases) were collected for isolation and identification of Salmonella enterica from Wasit Province of Iraq from January to December 2022 by using PCR assay and sequencing for three virulence factors genes (stn, avr A, and sop B). The results of isolation for S. enterica showed 4.6% (7/150) in humans, and 8.66% (13/150) in the chicken products (6/50 eggs, 3/50 livers, and 4/50 minced meat); Also showed 7/7 of S. typhi in human, while in the eggs showed 3/6 of S. typhi, 2/6 of S. typhimurium and 1/6 of S. enteritidis. Also, the results showed 3/3 and 4/4 of S. typhimurium in both livers and minced meat, respectively. The results of virulence factors recorded that the stn gene was absent in human isolates, while 10/13 in chicken products isolates, also showed in human and chicken products isolates 7/7 and 13/13, respectively, for both avr A and sop B genes. The serovare S. typhi were 10/10 carried both avr A and sop B genes, but lacked the stn gene. While S. typhimurium and S. enteritidis were 9/9 and 1/1 respectively carried stn, avr A and sop B genes. Sequencing was done for some PCR products for three virulence factors that were registered in NCBI. The nucleotide sequencing showed many nucleotide substitutions (mutations) in the sop B and avr A genes while no substitution in the stn gene.

Keywords

• salmonella enterica
• stn
• avr a
• sop b
• pcr