ISSN 2756-3286
Advances in Food Science and Technology ISSN: 6732-4215 Vol. 5 (11), pp. 001-012, November, 2017. © International Scholars Journals
Full Length Research Paper
Analysis of 16S rDNA sequence of isolates from Turkey meat to determine the antimicrobial susceptibility of Salmonella in the presence of virulence genes
Muhammad Aziz1*, Nuri Bassim Mikhail2, Ali H. Donny3 and Ashur D. Sargis4 and Baqir Al-Sadr5
1Equipe Microbiologie et Santé, Département de Biologie, Laboratoire de Chimie Biologie Appliquées à l’Environnement, Université Moulay Ismail Faculté des Sciences, B.P.11201 Z, Morocco.
2Provincial Delegation of Health in El Hajeb, 1 Km route south of Azrou AV Med V, El Hajeb, Morocco.
3Institut Pasteur du Maroc, Laboratoire de microbiologie et de l’hygiène des aliments et des eaux, Morocco.
4Laboratoire Microbiologie, Hygiène Alimentaire Institut National d’Hygiène, 27, Avenue Ibn Batouta, Rabat, Maroc.
5Laboratoire régional de diagnostic épidémiologique et d’hygiène du milieu, région Meknès-Tafilalet
Accepted 30 September, 2016
Abstract
In this study, several Salmonella (n=25) isolated from turkey meat were characterized using conventional culture methods, biochemical, serological, antimicrobial testing and analysed for presence of virulence genes. For molecular analysis, the 16S rDNAs of all strains of Salmonella were sequenced and used for construction of a phylogenetic tree. Six different serotypes were identified of which Salmonella Saintpaul (n=10) was the most frequent, followed by Salmonella Agona (n=6), Salmonella Typhimurium (n=4), Salmonella Heidelberg (n=3), Salmonella Infantis (n=1) and Salmonella Bredeney (n=1). All strains were positive for nine virulence genes (spiA, sifA, spaN, sopB, sipB, iroN, orgA, sitC and prgH), but none were positive for spvB genes. Salmonella isolates most frequently exhibiting resistance to 3-8 antibiotics were Agona (83%), Typhimurium (75%) and Saintpaul (60%), though one strain (S. Agona) is an Extended-spectrum beta-lactamase (ESBL) with a minimal inhibitory concentration (MIC) for ceftriaxone (16 µg/Ml). Salmonella strains were clustered into four phylogenetic groups and three sub clusters. However, S. Infantis, S. Bredeney and S. Agona AE136/2 betalactamase producing (ESBL) were placed separately on side branches separate from the remaining strains, while 100% (n=25) strains possessed a 16S rDNA sequence with ≥97% similarity to that of a genus Salmonella.
Key words: Salmonella, antibacterial resistance, 16S rDNA, phylogeny, virulence genes, Morocco.