Insights of biosurfactant producing Serratia marcescens strain W2.3 isolated from diseased tilapia fish: a draft genome analysis

Abstract

BackgroundSerratia marcescens is an opportunistic bacterial pathogen with broad range of host ranging from vertebrates, invertebrates and plants. S. marcescens strain W2.3 was isolated from a diseased tilapia fish and it was suspected to be the causal agent for the fish disease as virulence genes were found within its genome. In this study, for the first time, the genome sequences of S. marcescens strain W2.3 were sequenced using the Illumina MiSeq platform.ResultSeveral virulent factors of S. marcescens such as serrawettin, a biosurfactant, has been reported to be regulated by N-acyl homoserine lactone (AHL)-based quorum sensing (QS). In our previous studies, an unusual AHL with long acyl side chain was detected from this isolate suggesting the possibility of novel virulence factors regulation. This evokes our interest in the genome of this bacterial strain and hereby we present the draft genome of S. marcescens W2.3, which carries the serrawettin production gene, swrA and the AHL-based QS transcriptional regulator gene, luxR which is an orphan luxR.ConclusionWith the availability of the whole genome sequences of S. marcescens W2.3, this will pave the way for the study of the QS-mediated genes expression in this bacterium.

Characterization of <i>N</i>-acyl homoserine lactones (AHLs) producing bacteria isolated from vacuum-packaged refrigerated turbot (<i>Scophthalmus maximus</i>) and possible influence of exogenous AHLs on bacterial phenotype

“…Consistent with our result, they may have been C10-HSL or C12-HSL. The superiority of GC-MS compared with RP-TLC has also been exhibited in recent studies (Cataldi et al, 2007;Chan et al, 2011Chan et al, , 2013. In summary, short-chain AHLs were the predominate signaling in Serratia sp.…”

“…are Gram-negative, straight cells. These bacterial species are food-borne health-hazard opportunistic pathogens leading to pneumonia, intravenous catheter-associated infections, and osteomyelitis (Chan et al, 2013). Both of the bacterial strains widely exist in vacuum-packed refrigerated or iced raw food materials and have been reported to be involved in the spoilage of various aquatic food products, i.e., they have been isolated from spoiled cooked whole tropical shrimp (Penaeus vannamei) and spoiled raw salmon (Salmo salar) fillets stored under modified atmosphere packaging (Macé et al, 2012(Macé et al, , 2013.…”

Analysis of the genomic sequences and metabolites of Serratia surfactantfaciens sp. nov. YD25T that simultaneously produces prodigiosin and serrawettin W2

“…Therefore, serrawettin W2 has attracted interest as a potentially valuable antibiotic. At present, the available biosynthetic gene cluster for serrawettin W2 has not been identified, unless the 2.8 kb incomplete swr A is involved in the biosynthesis of the serrawettin W2 NRPS gene in S. marcescens MG1 [73] and S. marcescens A88copa13 [74]. In our study, a gene cluster of serrawettin W2 biosynthesis in YD25 T was directed by a hybrid PKS-NRPS system, and domain functions and a biosynthesis pathway were proposed.…”

“…S. marcescens Db10 is an insect pathogen that could produce serrawettin W2 but lacks the genes to produce prodigiosin [6]. There are pigment genes, and a 2631 bp sequence of swr A was found in S. marcescens W2.3 isolated from diseased tilapia fish; nevertheless, the related products have not been isolated and identified [74]. To date, YD25 T is the first reported Serratia strain that could concurrently produce the antibiotic secondary metabolite, prodigiosin and serrawettin W2 and also produce a spectrum of putative serrawettin W2 analogues simultaneously.…”

“…However, lux I and lux R genes do not occur in pairs in the YD25 T genome. The unpaired lux R gene has also been reported in the S. marcescens W2.3 genome [74]. Car R as a solo lux R, regulates the production of two secondary metabolite antibiotics, prodigiosin and carbapenem, in S. marcescens ATCC 39006 [77].…”