Transcriptome and proteome of fish-pathogenic Streptococcus agalactiae are modulated by temperature change

ABSTRACT: Streptococcus agalactiae is one of the most important pathogens associated with outbreaks of streptococcis in Nile tilapia farms around the world. High water temperature (above 27°C) have been described as factor predisposing for disease in fish. On the other hand, at low temperature (below 25°C) fish mortalities are no usually observed in farms. The temperature variation can modulate the expression of genes and proteins involved with metabolism, adaptation and bacterial pathogenicity, increasing or decreasing the host susceptibility to infection. The aim of this study was to evaluate the transcriptome and proteome of fish-pathogenic S. agalactiae strain (SA53) submitted to in vitro growth under different temperatures using microarray and label-free shotgun LC-HDMSE approach, and to compare the expression trends of proteins shared among GBS strains from different hosts (SA53 and NEM316). Biological triplicates of isolates were cultured in BHIT broth at 22°C or 32°C for RNA and protein isolation and submitted to transcriptomic and proteomic analysis. Total of 1730 transcripts were identified in SA53, being 107 genes differentially expressed among the temperature evaluated. A higher number of genes related with metabolism were detected as up-regulated proteins at 32°C, mainly PTS system and ABC transport system. In proteome analysis, 1046 proteins were identified in SA53 strain, being 81 proteins differentially regulated at 22 and 32ºC. Proteins involved in Defense mechanisms (V), Lipid transport and metabolism (I), and Nucleotide transport and metabolism (F) were up-regulated at 32ºC. A higher number of interactions was observed in the category F. The induction of genes/proteins involved in virulence were detected in both temperatures evaluated. A low correlation between transcriptome and proteome datasets was observed. And there is a distinct adaptation between fish and human GBS strains at the proteome level. Our study showed that the transcriptome and proteome of fish-adapted GBS strain are modulated by temperature, especially regulating the differential expression of genes/proteins involved with metabolism, adaptation and virulence, and revealing a host specificity at proteome regulation for human and fish hosts

ORGANISM(S): Streptococcus agalactiae

PROVIDER: GSE112416 | GEO | 2018/11/30

REPOSITORIES: GEO