Identification of Dalapon degrading bacterial strain, Psychrobacter sp. TaeBurcu001 isolated from Antarctica

Abstract

Extreme microorganism has gained interest because of their special contribution to the environmental and industrial biotechnology, particularly psychrophilic microorganisms which can live and thrive at lower temperatures. They produce enzymes with great potential to adapt to extreme conditions. In this study, a novel psychrophilic bacterial strain designated as TaeBurcu001 grew (optimally at 5.C) on a chemically defined medium containing dalapon (refer to as 2,2-dichloropropionic acid, 2,2-DCP) as the sole carbon source. TaeBurcu001 was isolated from Galindez Island, Antarctica. Phylogenetic analysis based on 16S rRNA gene sequence (GeneBank ID MN061637) showed that TaeBurcu001 was closely related to members of the genus Psychrobacter (99%). Comparisons of phenotypic and biochemical characteristics between the isolate and the other known Psychrobacter species showed that they are very similar. Chloride ion release was detected using colorimetric assay with maximum value recorded at 0.27 mmol/L in 30 mM of 2,2-DCP. Furthermore, the partial dehalogenase sequence of Psychrobacter TaeBurcu001 (GeneBank ID MW311072) showed a very high similarity (88%) to the previously reported 2-haloacid dehalogenase (DehE) from Rhizobium sp. (GeneBank ID CAA75671). To the best of our knowledge, this is the first study reporting on the isolation and characterisation of psychrophilic bacteria able to grow on halogenated compounds as a carbon source. Results are expected to gain new insight for further studies to uncover the full potential of these microorganisms to be applied in environmental processes and the remediation of contaminated ecosystems.