The gene encoding mycobacterial DNA-binding protein I (MDPI) transformed rapidly growing bacteria to slowly growing bacteria

Pathogenic species of Mycobacterium are slowly growing intracellular bacter ia. Slow growth is import-ant for the parasitism of these organisms and chr onicity of the disease, but its precise mechanism has not been elucidated. Recently, we found that a novel DNA-binding protein (MDPI) was expressed (7 -10% in total protein) in mycobacteria, such as Mycobacterium bovis bacillu s Calmette-Guerin, Mycobacterium tuberculosis, and Mycobacterium leprae. In this study, we observed that MDPI interfered with replication, transcripti on, and translation in the analysis in in vitro E. coli cell-free macromole cular biosynthesizing systems. Furthermore, MDPI inhibited the rapid growth of both Escherichia coli and Mycobacterium smegmatis, and NH2-terminal sec ond amino acid, asparagine, was observed to be important in terms of this f unction. These data suggest an important role of MDPI for suppression of gr owth rates of mycobacteria. (C) 2000 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved.