title: Presence of Salmonella pathogenicity island 2 genes in seafood-associated Salmonella serovars and the role of the sseC gene in survival of Salmonella enterica serovar Weltevreden in epithelial cells.
abstract: The type III secretion system encoded by the Salmonella pathogenicity island 2 (SPI-2) has a central role in the pathogenesis of systemic infections by Salmonella. Sixteen genes (ssaU, ssaB, ssaR, ssaQ, ssaO, ssaS, ssaP, ssaT, sscB, sseF, sseG, sseE, sseD, sseC, ssaD and sscA) of SPI-2 were targeted for PCR amplification in 57 seafood-associated serovars of Salmonella. The sseC gene of SPI-2 was found to be absent in two isolates of Salmonella enterica serovar Weltevreden, SW13 and SW39. Absence of sseC was confirmed by sequencing using flanking primers. SW13 had only 66 bp sequence of the sseC gene and SW39 had 58 bp sequence of this gene. A clinical isolate, S. Weltevreden--SW3, 10:r:z6--was used to construct a deletion mutant for the sseC gene. Significant reduction in the survival of SW3, 10:r:z6 ΔsseC and natural mutants SW13 and SW39 in HeLa cells suggests that sseC has a crucial role in the intracellular survival of S. Weltevreden. Expression of sseC was upregulated during the intracellular phase of both S. enterica serovar Typhimurium and clinical isolate S. Weltevreden SW3, 10:r:z6, suggesting a crucial role for this gene in the survival of S. Weltevreden inside host cells.
authors.affiliation: Department of Fishery Microbiology, Karnataka Veterinary, Animal and Fisheries Sciences University, College of Fisheries, Mangalore 575 002, India.
authors.forename: Patit P
authors.initials: PP
authors.lastname: Bhowmick
authors.affiliation: Department of Fishery Microbiology, Karnataka Veterinary, Animal and Fisheries Sciences University, College of Fisheries, Mangalore 575 002, India.
authors.forename: Devananda
authors.initials: D
authors.lastname: Devegowda
authors.affiliation: Department of Fishery Microbiology, Karnataka Veterinary, Animal and Fisheries Sciences University, College of Fisheries, Mangalore 575 002, India.
authors.forename: H A Darshanee
authors.initials: HAD
authors.lastname: Ruwandeepika
authors.affiliation: Department of Fishery Microbiology, Karnataka Veterinary, Animal and Fisheries Sciences University, College of Fisheries, Mangalore 575 002, India.
authors.forename: Iddya
authors.initials: I
authors.lastname: Karunasagar
authors.affiliation: Department of Fishery Microbiology, Karnataka Veterinary, Animal and Fisheries Sciences University, College of Fisheries, Mangalore 575 002, India.
authors.forename: Indrani
authors.initials: I
authors.lastname: Karunasagar
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics*; D004269:DNA, Bacterial / Q000235:genetics; D004847:Epithelial Cells / Q000382:microbiology*; D005798:Genes, Bacterial; D044404:Genomic Islands; D006367:HeLa Cells; D006801:Humans; D050296:Microbial Viability; D016133:Polymerase Chain Reaction; D012475:Salmonella / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity*; D012480:Salmonella Infections / Q000382:microbiology*; D012486:Salmonella typhimurium / Q000235:genetics / Q000472:pathogenicity; D017747:Seafood / Q000382:microbiology*; D037521:Virulence Factors / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; C502375:SseC protein, Salmonella typhimurium; D037521:Virulence Factors