Identification of the new Pseudomonas species for aquaculture and important biochemical characteristics

Introduction: The genus Pseudomonas is one of the most complex Gram-negative bacterialgenera as it currently is the genus with the largest number of species. While Pseudomonas causesevere disease for humans, the incidence or transmission route not known very well from aquacultureto humans. Recently, there are many possible novel Pseudomonas species identified,but a few of them identified from fish. In the present study, the identification of Pseudomonasspecies recovered from farmed salmonid species and the determination of the most importantbiochemical characteristics were aimed.Methodology: Pseudomonas species were isolated from farmed salmonids in Turkey, 2013 -2018. The strains were identified by 16S rRNA gene sequence analysis with the similarity indexon NCBI database. Growth condition of Pseudomonas spp. on different salinity, incubationtemperature, distilled and tap water were showed by using Tryptic soy broth media. In addition,the fluorescent pigment and biofilm production were determined by using Pseudomonas selectiveagar and broth media.Results: The Pseudomonas species isolated from rainbow trout (Onchorhynchus mykiss), localtrout species (Salvelinus fontinalis, Salmo trutta magrostigma, Salmo trutta labrax), Carp(Cyrpinus carpio) and also farm water samples. More than ten different Pseudomonas specieswere identified with the similarity of NCBI database such as P. jessenii, P. madelii, P. gessardiiand a number of them are possible for novel species. The most of our isolates could growth on0 - 6% NaCl-TSB medium, distilled and tap water and also 4 - 37 °C incubation temperature.Conclusion: This is the first comprehensive research about Pseudomonas species determinationon aquaculture in Turkey. The identified species were determined in the first time in salmonidsand also some of them are possible novel Pseudomonas species isolated from aquaculture. Alsoour findings showed that the Pseudomonas can growth on distilled and tap water in additionbroad range of salinity and incubation temperature. Thus, the transmission of this agent fromaquaculture to human/animal/environment via water pose a big risk factor.Keywords: Pseudomonas, new species, biochemical characteristicsFunding: Scientific and Technological Research Council (TUBITAK) of Turkey, project number:118O420.