Isolation identification molecular characterization and comparative studies of salmonella spp isolated from various food environmental and clinical specimens from Nanded district of Maharashtra

Abstract

Salmonella spp. reported to be one of the most important food pathogen studied worldwide. Salmonella causes typhoidal and non-typhoidal diseases in humans and animals. The economic losses are too big to ignore and measures has to be taken in order to prevent the spread of the microbe and also to study the genetic relatedness. In this research salmonella spp. from poultry products, environmental, and clinical specimens are isolated and identified using RT PCR technique. The genetic relatedness of the isolates was correlated using bioinformatics software, Applied Math. 48, 44, and 27 isolates of salmonella spp. were isolated form poultry, environmental and clinical respectively. A standard salmonella isolation method was used in the bacterial isolation. Colonies from microbial plates were confirmed using MicroSEQ Salmonella spp. Detection Kits, and Step One Plus RT PCR Machine from Applied Biosystems. A genetic dendrogram was generated using Applied Math software from the PFGE gels generated by Xbal digestion of the strains and using Salmonella braenderup (H9812) as reference strain. All gels were analyzed groupwise according to the source and combined. It was found that the strains from poultry and environmental sources had similar band patterns, which are 100% identical. While clinical specimen isolates did not show any similarity to any strains from other two sources or even to each other. Isolates from the poultry exhibited maximum number of similarity groups (3 groups) with a total of 29 isolates, among which 3 in the first group and 11 and 15 strains in the second and third group respectively. Environmental isolates had 6 groups of isolates spread over two clusters. In cluster A, 3 different groups with 2, 3 and 6 isolates produced indistigutiable band patterns. Cluster B, composed of 3 groups with 2, 8 and 2 isolates from both soil and sewage sources across different places. When all isolates analyzed together, the dendrogram produced 2 groups of isolates among poultry and environmental sources w