Project description:Edwardsiella ictaluri and Edwardsiella piscicida are important fish pathogens affecting cultured and wild fish worldwide. To investigate the genome-level differences and similarities between catfish-adapted strains in these two species, the complete E. ictaluri 93-146 and E. piscicida C07-087 genomes were evaluated by applying comparative genomics analysis. All available complete (10) and non-complete (19) genomes from five Edwardsiella species were also included in a systematic analysis. Average nucleotide identity and core-genome phylogenetic tree analyses indicated that the five Edwardsiella species were separated from each other. Pan-/core-genome analyses for the 29 strains from the five species showed that genus Edwardsiella members have 9474 genes in their pan genome, while the core genome consists of 1421 genes. Orthology cluster analysis showed that E. ictaluri and E. piscicida genomes have the greatest number of shared clusters. However, E. ictaluri and E. piscicida also have unique features; for example, the E. ictaluri genome encodes urease enzymes and cytochrome o ubiquinol oxidase subunits, whereas E. piscicida genomes encode tetrathionate reductase operons, capsular polysaccharide synthesis enzymes and vibrioferrin-related genes. Additionally, we report for what is believed to be the first time that E. ictaluri 93-146 and three other E. ictaluri genomes encode a type IV secretion system (T4SS), whereas none of the E. piscicida genomes encode this system. Additionally, the E. piscicida C07-087 genome encodes two different type VI secretion systems. E. ictaluri genomes tend to encode more insertion elements, phage regions and genomic islands than E. piscicida. We speculate that the T4SS could contribute to the increased number of mobilome elements in E. ictaluri compared to E. piscicida. Two of the E. piscicida genomes encode full CRISPR-Cas regions, whereas none of the E. ictaluri genomes encode Cas proteins. Overall, comparison of the E. ictaluri and E. piscicida genomes reveals unique features and provides new insights on pathogenicity that may reflect the host adaptation of the two species.
Project description:Edwardsiella ictaluri is the causitive agent of enteric septicemia of catfish, one of the most important diseases impacting US catfish industry. The overall objective of this study is to identify E. ictaluri genes required for host encounter.
Project description:Edwardsiella ictaluri is the causitive agent of enteric septicemia of catfish, one of the most important diseases impacting US catfish industry. The overall objective of this study is to identify E. ictaluri genes required for serum resistance.
Project description:Edwardsiella ictaluri is the cause of extensive mortalities and economic losses to the channel catfish industry of the southeast United States. Here we report the complete genome of Edwardsiella ictaluri 93-146. Whole-genome sequence analysis of E. ictaluri provides a tool for understanding the genomic regions specific to the species and the Edwardsiella genus.
Project description:Edwardsiella ictaluri is the causitive agent of enteric septicemia of catfish, one of the most important diseases impacting US catfish industry. The overall objective of this study is to identify E. ictaluri genes required for host encounter. 4-plex NimbleGen array study using total RNA obtained from wild type and mutant Edwardsiella ictaluri encountered with or without catfish fry. Each treatment had four biological replica and each plex had two probe sets.
Project description:Edwardsiella ictaluri is the causitive agent of enteric septicemia of catfish, one of the most important diseases impacting US catfish industry. The overall objective of this study is to identify E. ictaluri genes required for serum resistance. 4-plex array study using total RNA obtained from wild type and mutant Edwardsiella ictaluri exposed to heat-inactivated catfish serum and normal serum. Each treatment had four biological replica and each plex had two probe sets.