Biomaterial Database

Virulence factors of Aeromonas salmonicida subsp. salmonicida strains associated with infections in turbot Psetta maxima. 2012

E P Lago, and T P Nieto, and R Farto

Departamento de Biología Funcional y Ciencias de la Salud, Universidad de Vigo, Vigo, Spain.

Virulence factors for Aeromonas salmonicida subsp. salmonicida (ASS) strains isolated from cultured turbot Psetta maxima L. are unknown with regard to this host. The presence of virulence genes associated with different stages of ASS infection in salmonids (vapA, tapA, fla, ascV, ascC, aexT, satA and aspA) was analysed using a polymerase chain reaction (PCR) technique in ASS strains isolated from turbot. Other ASS strains isolated from salmonids and environmental A. salmonicida (AS) strains were included for comparison. The presence of the genes was evaluated with respect to ASS virulence in turbot based on intraperitoneal and bath challenges. The genetic profile, including all of the genes studied, that was linked to virulent behaviour after intraperitoneal challenge was significantly more frequent in strains isolated from turbot than in those from salmonids or the environment. The data prove that it is not possible to predict the virulence of ASS in turbot based only on the presence of all genes tested. Moreover, the combined PCR results of vapA, aexT, ascV and ascC were useful for separating most of the ASS from environmental A. salmonicida strains. An association between virulence or genetic profile and the geographical or facility origin of the strains was not found.

UI	MeSH Term	Description	Entries
D005393	Fish Diseases	Diseases of freshwater, marine, hatchery or aquarium fish. This term includes diseases of both teleosts (true fish) and elasmobranchs (sharks, rays and skates).	Disease, Fish,Diseases, Fish,Fish Disease
D005412	Flatfishes	Common name for the order Pleuronectiformes. A very distinctive group in that during development they become asymmetrical, i.e., one eye migrates to lie adjacent to the other. They swim on the eyeless side. FLOUNDER, sole, and turbot, along with several others, are included in this order.	Pleuronectiformes,Scophthalmus maximus,Turbot,Psetta maxima,Solea,Turbots
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D014774	Virulence	The degree of pathogenicity within a group or species of microorganisms or viruses as indicated by case fatality rates and/or the ability of the organism to invade the tissues of the host. The pathogenic capacity of an organism is determined by its VIRULENCE FACTORS.	Pathogenicity
D015964	Gene Expression Regulation, Bacterial	Any of the processes by which cytoplasmic or intercellular factors influence the differential control of gene action in bacteria.	Bacterial Gene Expression Regulation,Regulation of Gene Expression, Bacterial,Regulation, Gene Expression, Bacterial
D016133	Polymerase Chain Reaction	In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.	Anchored PCR,Inverse PCR,Nested PCR,PCR,Anchored Polymerase Chain Reaction,Inverse Polymerase Chain Reaction,Nested Polymerase Chain Reaction,PCR, Anchored,PCR, Inverse,PCR, Nested,Polymerase Chain Reactions,Reaction, Polymerase Chain,Reactions, Polymerase Chain
D016905	Gram-Negative Bacterial Infections	Infections caused by bacteria that show up as pink (negative) when treated by the gram-staining method.	Bacterial Infections, Gram-Negative,Infections, Gram-Negative Bacterial,Bacterial Infection, Gram-Negative,Gram Negative Bacterial Infections,Gram-Negative Bacterial Infection,Infection, Gram-Negative Bacterial
D048409	Aeromonas salmonicida	A species of gram-negative bacteria, in the family Aeromonadaceae. It is strictly parasitic and often pathogenic causing FURUNCULOSIS in SALMONIDS and ulcer disease in GOLDFISH.
D037521	Virulence Factors	Those components of an organism that determine its capacity to cause disease but are not required for its viability per se. Two classes have been characterized: TOXINS, BIOLOGICAL and surface adhesion molecules that effect the ability of the microorganism to invade and colonize a host. (From Davis et al., Microbiology, 4th ed. p486)	Pathogenicity Factor,Pathogenicity Factors,Virulence Factor,Factor, Pathogenicity,Factor, Virulence,Factors, Pathogenicity,Factors, Virulence