4IDM

Crystal structure of the Delta-pyrroline-5-carboxylate dehydrogenase from Mycobacterium tuberculosis

Summary for 4IDM

• Entry DOI: 10.2210/pdb4idm/pdb
• Related: 4IDS
• Descriptor: Delta-1-pyrroline-5-carboxylate dehydrogenase (2 entities in total)
• Functional Keywords: pyrroline dehydrogenase, aldehyde dehydrogenase, pyrroline-5-carboxylate dehydrogeanse, pyrroline-5-carboxylic acid, dehydrogenation, oxidoreductase
• Biological source: Mycobacterium tuberculosis
• Total number of polymer chains: 1
• Total formula weight: 61556.62

Authors

Lagautriere, T.,Bashiri, G.,Baker, E.N. (deposition date: 2012-12-12, release date: 2013-12-18, Last modification date: 2014-04-16)

Primary citation

Lagautriere, T.,Bashiri, G.,Paterson, N.G.,Berney, M.,Cook, G.M.,Baker, E.N.
Characterization of the proline-utilization pathway in Mycobacterium tuberculosis through structural and functional studies.
Acta Crystallogr.,Sect.D, 70:968-980, 2014

PubMed Abstract: The proline-utilization pathway in Mycobacterium tuberculosis (Mtb) has recently been identified as an important factor in Mtb persistence in vivo, suggesting that this pathway could be a valuable therapeutic target against tuberculosis (TB). In Mtb, two distinct enzymes perform the conversion of proline into glutamate: the first step is the oxidation of proline into Δ(1)-pyrroline-5-carboxylic acid (P5C) by the flavoenzyme proline dehydrogenase (PruB), and the second reaction involves converting the tautomeric form of P5C (glutamate-γ-semialdehyde) into glutamate using the NAD(+)-dependent Δ(1)-pyrroline-5-carboxylic dehydrogenase (PruA). Here, the three-dimensional structures of Mtb-PruA, determined by X-ray crystallography, in the apo state and in complex with NAD(+) are described at 2.5 and 2.1 Å resolution, respectively. The structure reveals a conserved NAD(+)-binding mode, common to other related enzymes. Species-specific conformational differences in the active site, however, linked to changes in the dimer interface, suggest possibilities for selective inhibition of Mtb-PruA despite its reasonably high sequence identity to other PruA enzymes. Using recombinant PruA and PruB, the proline-utilization pathway in Mtb has also been reconstituted in vitro. Functional validation using a novel NMR approach has demonstrated that the PruA and PruB enzymes are together sufficient to convert proline to glutamate, the first such demonstration for monofunctional proline-utilization enzymes.

PubMed: 24699642
DOI: 10.1107/S1399004713034391

Experimental method

X-RAY DIFFRACTION (2.5 Å)