Biphenyl Dioxygenase from an Arctic Isolate is not Cold-Adapted

Department of Microbiology and Immunology, Life Sciences Centre, University of British Columbia, Vancouver, British Columbia, V6T 1Z3, Canada; Department of Chemistry and Biochemistry, Concordia University, Montreal, Quebec, H4B 1R6, Canada

^* To whom correspondence should be addressed. Email: leltis{at}interchange.ubc.ca.

	Abstract

Biphenyl dioxygenase from the psychrotolerant bacterium Pseudomonas sp. Cam-1 (BPDO_Cam1) was purified and found to have a k_cat^app for biphenyl of 1.1 ± 0.1 s^-1 at 4°C. In contrast, BPDO_LB400 from a mesophile had no detectable activity at this temperature. At 57°C, the t of the BPDO_Cam1 oxygenase was less than half that of BPDO_LB400's. Nevertheless, BPDO_Cam1 appears to be a typical KF707-type dioxygenase.