IUCr journals

The molecular structure of Rv2074, a probable pyridoxine 5′-phosphate oxidase from Mycobacterium tuberculosis, at 1.6 Å resolution

Acta Cryst. (2006). F62, 735–742 [doi.org/10.1107/S1744309106025012]

[Electron density map]The 2|Fo|-|Fc| electron-density map (blue) contoured at the 1σ level, showing two citric acid molecules bound in the active site of Rv2074. The citrate carbon and oxygen atoms are shown in grey and red colors, respectively. Also shown are the sodium atom (magenta) and two coordinating water molecules (red).
In an attempt to predict the biological functions of conserved hypothetical proteins among the Actinomycetes subgroup of bacteria from their three-dimensional structures, the crystal structure of Rv2074 from Mycobacterium tuberculosis (Mtb) was determined. Rv2074 is a dimer in the crystals; each monomer folds into a six-stranded antiparallel β-barrel flanked by two α-helices. Owing to its extensive structural similarity with Mtb Rv1155 and to the E. coli and human pyridoxine 5′-phosphate oxidases, Rv2074 may possibly be involved in the final step in the biosynthesis of pyridoxal 5′-phosphate (PLP, vitamin B6). Two citric acid molecules are bound fortuitously to the proposed active site of Rv2074.

Bichitra K. Biswal, Karolyn Au, Maia M. Cherney, Craig Garen and Michael N.G. James