title: Sortase inhibitor phenyl vinyl sulfone inhibits Renibacterium salmoninarum adherence and invasion of host cells.
abstract: Renibacterium salmoninarum, the causative agent of bacterial kidney disease in salmonid fishes, is a Gram-positive diplococcobacillus belonging to the family Micrococcaceae. Analysis of the genome sequence of the bacterium demonstrated the presence of a sortase homolog (srtD), a gene specifying an enzyme found in Gram-positive bacteria and required for covalent anchoring of cell surface proteins. Interference of sortase activity is being examined as a target for therapeutic prevention of infection by several pathogenic Gram-positive bacterial species. In silico analysis identified 8 open reading frames containing sortase recognition motifs, suggesting these proteins are translocated to the bacterial cell wall. The sortase and potential sortase substrate genes are transcribed in R. salmoninarum, suggesting they encode functional proteins. Treatment of R. salmoninarum with phenyl vinyl sulfone (PVS) significantly reduced bacterial adherence to Chinook salmon fibronectin. In addition, the ability of the PVS-treated bacteria to adhere to Chinook salmon embryo cells (CHSE-214) in vitro was dramatically reduced compared to that of untreated bacteria. More importantly, PVS-treated bacteria were unable to invade and replicate within CHSE-214 cells (demonstrated by an intracellular growth assay and by light microscopy). When treated with PVS, R. salmoninarum was not cytopathic to CHSE-214 cells, whereas untreated bacteria produced cytopathology within a few days. These findings clearly show that PVS, a small molecule drug and a known sortase inhibitor, can interfere with the ability of R. salmoninarum to adhere and colonize fish cells, with a corresponding decrease in virulence.
authors.affiliation: Northwest Fisheries Science Center, NOAA Fisheries Service, 2725 Montlake Boulevard East, Seattle, Washington 98112, USA.
authors.forename: Ponnerassery S
authors.initials: PS
authors.lastname: Sudheesh
authors.forename: Samuel
authors.initials: S
authors.lastname: Crane
authors.forename: Kenneth D
authors.initials: KD
authors.lastname: Cain
authors.forename: Mark S
authors.initials: MS
authors.lastname: Strom
mesh_terms: D000193:Actinomycetales Infections / Q000382:microbiology / Q000473:pathology / Q000662:veterinary; D000595:Amino Acid Sequence; D019881:Aminoacyltransferases / Q000737:chemistry / Q000235:genetics; D000818:Animals; D001422:Bacterial Adhesion / Q000187:drug effects*; D001426:Bacterial Proteins / Q000032:analysis / Q000737:chemistry / Q000235:genetics; D001483:Base Sequence; D002460:Cell Line; D003546:Cysteine Endopeptidases / Q000737:chemistry / Q000235:genetics; D004269:DNA, Bacterial / Q000737:chemistry; D004625:Embryo, Nonmammalian / Q000166:cytology; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005353:Fibronectins / Q000187:drug effects / Q000378:metabolism; D005393:Fish Diseases / Q000382:microbiology; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects; D008835:Micrococcaceae / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics / Q000472:pathogenicity*; D008969:Molecular Sequence Data; D012474:Salmon / Q000382:microbiology; D016415:Sequence Alignment; D013450:Sulfones / Q000494:pharmacology*; D013997:Time Factors
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004791:Enzyme Inhibitors; D005353:Fibronectins; D013450:Sulfones; C512310:phenyl vinyl sulfone; D019881:Aminoacyltransferases; D003546:Cysteine Endopeptidases