%0 Journal Article
%T The Main Aeromonas Pathogenic Factors
%A J. M. Tom¨˘s
%J ISRN Microbiology
%D 2012
%R 10.5402/2012/256261
%X The members of the Aeromonas genus are ubiquitous, water-borne bacteria. They have been isolated from marine waters, rivers, lakes, swamps, sediments, chlorine water, water distribution systems, drinking water and residual waters; different types of food, such as meat, fish, seafood, vegetables, and processed foods. Aeromonas strains are predominantly pathogenic to poikilothermic animals, and the mesophilic strains are emerging as important pathogens in humans, causing a variety of extraintestinal and systemic infections as well as gastrointestinal infections. The most commonly described disease caused by Aeromonas is the gastroenteritis; however, no adequate animal model is available to reproduce this illness caused by Aeromonas. The main pathogenic factors associated with Aeromonas are: surface polysaccharides (capsule, lipopolysaccharide, and glucan), S-layers, iron-binding systems, exotoxins and extracellular enzymes, secretion systems, fimbriae and other nonfilamentous adhesins, motility and flagella. 1. Introduction Ever since the first reference of an organism that could be considered a motile aeromonad in 1891 the taxonomy of the genus Aeromonas, initiated in 1943, is complex and continuously changing. Although historically the genus Aeromonas was included in the family Vibrionaceae, together with the genera Vibrio, Photobacterium, and Plesiomonas, phylogenetic investigations indicated that they should form their own family: Aeromonadaceae [1]. The family Aeromonadaceae consists of Gram-negative, facultative anaerobic, chemoorganotroph bacteria with an optimal growing temperature of about 22ˇăC to 28ˇăC. Generally they are motile by polar flagellation, able to reduce nitrates to nitrites and able to catabolize glucose and several carbohydrates while producing acids and often gases as well. Initially, in BergeyˇŻs Manual of Systematic Bacteriology this family only included the genus Aeromonas and was divided into two principal subgroups: the nonmotile and psycnrophilic species (A. salmonicida) and the motile and mesophilic species (A. hydrophila, A. caviae, and A. sobria) [2]. The current edition, list three genera in this family: Aeromonas, Oceanimonas, and Tolumonas [3]. The first classifications within the Aeromonas genus have been determined phenotypically (phenospecies), based on growth characteristics and biochemical tests. Nevertheless, there is a great difficulty in identifying the different Aeromonas strains on a species level by these characteristics, due to the phenotypical heterogeneity and growing number of known species [4]. One of the
%U http://www.hindawi.com/journals/isrn.microbiology/2012/256261/