Dataset for: Structural and genetic analysis of START superfamily protein MSMEG_0129 from <i>Mycobacterium smegmatis</i>

<i>Mycobacterium tuberculosis</i>, a notorious pathogen, still threatens human health. Rv0164, an antigen of both T- and B-cells conserved across the mycobacteria, and MSMEG_0129, its close homolog in <i>Mycobacterium smegmatis</i>, are predicted members of the START domain superfamily, but their molecular function is unknown. Here, gene knockout studies demonstrated MSMEG_0129 is essential for bacterial growth, suggesting Rv0164 may be a potential drug target. The MSMEG_0129 crystal structure determined at 1.95 Å reveals a fold similar to that in polyketide aromatase/cyclases ZhuI and TcmN from <i>Streptomyces sp.</i>. Structural comparisons and docking simulations, however, infer that MSMEG_0129 and Rv0164 are unlikely to catalyze polyketide aromatization/cyclization, but probably play an irreplaceable role, for example in lipid transfer, in cell envelope synthesis during mycobacterial growth.