Abstract:
Multi drug resistant Salmonella enterica is one of the most important foodborne pathogens
and mainly associated with gastroenteritis infection both in humans and animals. The
irrational use of antibiotics has developed potential antimicrobial resistance in non typhoidal S. enterica. Currently, the number of human infections caused by Salmonella
enterica serovar Infantis has been rising worldwide as these strains have become multi
drug resistant. Whole Genome Sequencing has become an important tool in the
surveillance of antimicrobial resistance in S. enterica. The aim of this study was whole
genome sequencing-based genome analysis of three indigenous strains of Salmonella
Infantis and detection of genetic components responsible for antimicrobial resistance in
them. Result revealed the genome size of all three strains, S. Infantis RW51, S. Infantis
RW52, and S. Infantis SKR55 is approximately 4.8Mb with 52.0% GC content. These
strains harbour resistance determinants; golA, sdiA, adeF. kpnE, rsmA, APH(3')-Iia,
ANT(3'')-Iia, tet(A), gyrA and arr-2 that provide resistance to beta-lactams,
aminoglycosides, tetracycline, macrolides, fluoroquinolones Chloramphenicol,
sulfonamides and rifampicin. Several genetic factors such as mobile genetic elements,
prophages and insertion sequences were also identified that influence the genetic and
phenotypic diversity of antimicrobial resistance and virulence in them. Phylogenetic
analysis inferred that RW51 and RW52 are evolutionarily related to strain S. Infantis
119944 reported from Israel while SKR55 is found to be closely related to strain
VNCSE001 reported from Vietnam.
