Gene expression of Vibrio parahaemolyticus growing in laboratory isolation conditions compared to those common in its natural ocean environment

Abstract

Background Vibrio parahaemolyticus is an autochthonous marine bacterial species comprising strains able to grow in broth containing bile salts at 37 °C, a condition seldom found in the ocean. However, this condition is used for isolation in the laboratory because it is considered a necessary property for pathogenesis. In this context, revealing how gene expression enables V. parahaemolyticus to adapt to this particular condition –common to almost all V. parahaemolyticus isolates- will improve our understanding of the biology of this important pathogen. To determine the genes of V. parahaemolyticus differentially expressed when growing in isolation condition (37 °C, 0.9% NaCl, and 0.04% bile salts) referred to those at the temperature and salt concentration prevailing in ocean south of Chile (marine-like condition; 12 °C, 3% NaCl, and absence of bile salts) we used high-throughput sequencing of RNA.ResultsOur results showed that in the isolation condition, among the 5034 genes annotated in the V. parahaemolyticus RIMD2210633 genome, 344 were upregulated and 433 downregulated referred to the marine-like condition, managing an adjusted P-value (Padj) < E−5. Between the 50 more highly expressed genes, among the small RNAs (sRNA), the three carbon storage regulators B (CsrB) were up four to six times, while RyhB, related to iron metabolism besides motility control, was down about eight times. Among proteins, BfdA, a hemolysin-co-regulated protein (Hcp1) secreted by T6SS1, one of the most highly expressed genes, was about 140 times downregulated in isolation condition. The highest changes in relative expression were found among neighboring genes coding for proteins related to respiration, which were about 40 times upregulated.ConclusionsWhen V. parahaemolyticus is grown in conditions used for laboratory isolation 777 genes are up- or downregulated referred to conditions prevailing in the marine-like condition; the most significantly overrepresented categories among upregulated processes were those related to transport and localization, while secretion and pathogenesis were overrepresented among downregulated genes. Genes with the highest differential expression included the sRNAs CsrB and RhyB and the mRNAs related with secretion, nutritional upshift, respiration and rapid growing.Electronic supplementary materialThe online version of this article (doi:10.1186/s12866-017-1030-6) contains supplementary material, which is available to authorized users.

Holistic analysis of lysine acetylation in aquaculture pathogenic bacteria Vibrio alginolyticus under bile salt stress

“…Pick monoclonal colonies from TSB (Tryptone Soya Broth, Oxoid U.S.A., Inc., Columbia, Md) medium plates into TSB liquid medium for overnight culture. The next day, overnight culture transfer by 1% to a fresh TSB medium containing 0.04% bile salts (Sigma-Aldrich, St. Louis, MO) ( 32 ) and culture until the OD was about 1.0, and then collect cells were by centrifugation. The pellet was washed twice with pre-cooled PBS (Phosphate Buffered Saline) and dissolved in lysis buffer [containing 100 mM NH 4 HCO 3 (pH 8), 6 M Urea and 0.2% SDS], followed by 5 min of ultrasonication on ice.…”

Survival and Genome Diversity of Vibrio parahaemolyticus Isolated from Edible Aquatic Animals

“…A total of 1718 V. parahaemolyticus isolates have been sequenced (GenBank database, https://www.ncbi.nlm.nih.gov/, accessed on 17 September 2021), among which, complete genome sequences of 63 V. parahaemolyticus isolates are now available. Nevertheless, few studies on comparative genome analyses of these V. parahaemolyticus genomes have yet been conducted [3,8,21,22].…”

Conservation of Small Regulatory RNAs in Vibrio parahaemolyticus: Possible role of RNA-OUT Encoded by the Pathogenicity Island (VPaI-7) of Pandemic Strains

“…Another study recently showed that, besides Spot42 and RhyB, one qrr sRNA was significantly upregulated during infection of pandemic V. parahaemolyticus in an animal model compared to laboratory culture conditions [21]. Similarly, our group also demonstrated that the expression of sRNAs in V. parahaemolyticus changes when bacterial growth conditions are modified [20].…”

“…Only two of the 43 sRNAs described in V. parahaemolyticus have been experimentally studied, RyhB [18] and Spot42 [19]. The former modulates the expression of several genes related to motility, chemotaxis, biofilm formation, and iron metabolism [18,20], while Spot42 post-transcriptionally regulates the expression of chaperone protein VP1682 of the Type III secretion system of chromosome 1 (T3SS1) [19], suggesting a role in cytotoxicity. Another study recently showed that, besides Spot42 and RhyB, one qrr sRNA was significantly upregulated during infection of pandemic V. parahaemolyticus in an animal model compared to laboratory culture conditions [21].…”