A new subfamily of short bacterial adenylate kinases with the Mycobacterium tuberculosis enzyme as a model: A predictive and experimental study

The adk gene from Mycobacterium tuberculosis codes for an enzyme of 181 ami no acids. A sequence comparison with 52 different forms of adenylate kinase s (AT) suggests that the enzyme from M. tuberculosis belongs to a new subfa mily of "short" bacterial AKs. The recombinant protein, over-expressed in E scherichia coil, exhibits a low catalytic activity and an unexpectedly high thermal stability (Tm = 64.8 degrees C). Based on various spectroscopic da ta, on the known three-dimensional structure of the AR from E. coli and on secondary structure predictions for various sequenced AKs, we propose a str uctural model for AK from M. tuberculosis (AKmt). (C) 1999 Wiley-Liss, Inc.