Potential virulence-associated properties of Plesiomonas shigelloides strains.

Serotyping and some potential virulence-associated markers were investigated in Plesiomonas shigelloides strains isolated from humans, animals and aquatic environments. Surface properties of these strains were evaluated using Congo red binding, salt-aggregation test, bacterial adherence to xylene and motility. Production of pancreatic elastase, proteinase (consistent with subtilisin Carlsberg), triacylglycerol lipase, histidine decarboxylase and beta-hemolysin was also determined. In addition, detection of signal molecules such as C4-C8 unsubstituted N-acylhomoserine lactones (AHLs) was performed. The serological typing of the P. shigelloides strains showed that the isolates belonged to 13 different serovars. The majority of the strains were hydrophobic and motile. The strains produced low levels of elastase, proteinase and histidine decarboxylase whereas triacylglycerol lipase activity was relatively high. Only 23.3 % of the strains produced hemolysin. The AHLs signal molecules were not detected. P. shigelloides strains were able to produce a variety of potential virulence markers which may be involved in the pathogenesis of Plesiomonas-associated infections.