Comparative Pathogenomics of Bacteria Causing Infectious Diseases in Fish

Abstract

Fish living in the wild as well as reared in the aquaculture facilities are susceptible to infectious diseases caused by a phylogenetically diverse collection of bacterial pathogens. Control and treatment options using vaccines and drugs are either inadequate, inefficient, or impracticable. The classical approach in studying fish bacterial pathogens has been looking at individual or few virulence factors. Recently, genome sequencing of a number of bacterial fish pathogens has tremendously increased our understanding of the biology, host adaptation, and virulence factors of these important pathogens. This paper attempts to compile the scattered literature on genome sequence information of fish pathogenic bacteria published and available to date. The genome sequencing has uncovered several complex adaptive evolutionary strategies mediated by horizontal gene transfer, insertion sequence elements, mutations and prophage sequences operating in fish pathogens, and how their genomes evolved from generalist environmental strains to highly virulent obligatory pathogens. In addition, the comparative genomics has allowed the identification of unique pathogen-specific gene clusters. The paper focuses on the comparative analysis of the virulogenomes of important fish bacterial pathogens, and the genes involved in their evolutionary adaptation to different ecological niches. The paper also proposes some new directions on finding novel vaccine and chemotherapeutic targets in the genomes of bacterial pathogens of fish.

The Potential Exploitation of the Mediterranean Invasive Alga Caulerpa cylindracea: Can the Invasion Be Transformed into a Gain?

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Sensors, Biosensors, and Analytical Technologies for Aquaculture Water Quality

“…Fish and fish productrelated bacteria and virus are diverse. Based on the extent of infection, some of them only infect or kill fishes without infecting human, e.g., Vibrio harveyi, Vibrio anguillarum, and Aeromonas salmonicida [81,82], but some of them can infect both fish and human such as Vibrio vulnificus, Mycobacterium marinum, and Streptococcus iniae [83]. There are also pathogens that may not necessarily infect the fish, but infect human through consumption of contaminated fish 7 Research products, e.g., Vibrio cholerae, Escherichia coli, and Salmonella spp.…”

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