Studies on structural and functional divergence among seven WhiB proteins of Mycobacterium tuberculosis H37Rv

摘要: The whiB-like genes (1-7) of Mycobacterium tuberculosis are involved in cell division, nutrient starvation, pathogenesis, antibiotic resistance and stress sensing. Although the biochemical properties WhiB1, WhiB3 WhiB4 known, there is no information about other proteins. Here, we elucidate detail biophysical WhiB2, WhiB5, WhiB6 WhiB7 M. present a comprehensive comparative study on molecular all WhiB UV-Vis spectroscopy has suggested presence redox-sensitive [2Fe-2S] cluster each proteins, which remains stably bound to proteins 8 m urea. protein was oxidation labile but rate loss decreased under reducing environments. responded differently oxidative effect air oxidized glutathione. In cases, disassembly coupled with cysteine-thiols formation two intramolecular disulfide bonds. Both CD fluorescence revealed that structurally divergent members same family. Similar WhiB4, apo also reduced insulin, model substrate. However, reduction efficiency varied significantly. Surprisingly, WhiB2 did not reduce insulin disulfide, even though its basic were similar those others. structural functional divergence among indicated distinguished member family together they may represent novel redox system for tuberculosis.