Gram-negative halophilic bacteria-destructors of ortho-phthalate

Five strains of gram-negative bacteria-destructors of ortho-phthalate (ortho-PA), isolated from bottom sediments and potash production wastes of the region of potassium salt mining (Berezniki, Perm Region), were selected from the working collection of microorganisms (Laboratory of Molecular Microbiology and Biotechnology, Institute of Ecology and Genetics of Microorganisms, UB RAS). Based on phylogenetic analysis (16S rRNA genes), the strains have been identified as members of the genera Pseudomonas, Idiomarina, Alcanivorax, Martelella, Breoghania. It was established that the strains are halotolerant microorganisms and are capable of growth on a complete medium in the presence of up to 100 g/L NaCl, as well as growth on ortho-PA as a substrate with up to 70 g/L of salt in the culture medium. When grown in medium with increased salinity (30 g/l NaCl), most strains showed higher growth characteristics (maximum OD600, exponential growth rate) than in medium without salt addition. The strain Idiomarina sp. PSH17-1 revealed increased parameters of optical density and exponential growth rate in a medium with 50 and 70 g/l of salt. The features of the ortho-PA destruction for strains of the genus Martelella have not been previously described. The results of the study can serve as the basis for the development of effective biotechnologies for detoxification and monitoring of phthalates in contaminated saline soils.