5XKO
Crystal structure of native Msmeg3575 deaminase from Mycobacterium smegmatis
Summary for 5XKO
| Entry DOI | 10.2210/pdb5xko/pdb |
| Related | 5XKP 5XKQ 5XKR |
| Descriptor | Cytidine/deoxycytidylate deaminase, zinc-binding region, CACODYLATE ION, GLYCEROL, ... (6 entities in total) |
| Functional Keywords | hydrolase, deaminase, cda fold, mutagens |
| Biological source | Mycobacterium smegmatis (strain ATCC 700084 / mc(2)155) |
| Total number of polymer chains | 2 |
| Total formula weight | 35188.69 |
| Authors | Gaded, V.M.,Anand, R. (deposition date: 2017-05-08, release date: 2017-08-09, Last modification date: 2024-03-27) |
| Primary citation | Gaded, V.,Anand, R. Selective Deamination of Mutagens by a Mycobacterial Enzyme J. Am. Chem. Soc., 139:10762-10768, 2017 Cited by PubMed Abstract: Structure-based methods are powerful tools that are being exploited to unravel new functions with therapeutic advantage. Here, we report the discovery of a new class of deaminases, predominantly found in mycobacterial species that act on the commercially important s-triazine class of compounds. The enzyme Msd from Mycobacterium smegmatis was taken as a representative candidate from an evolutionarily conserved subgroup that possesses high density of Mycobacterium deaminases. Biochemical investigation reveals that Msd specifically acts on mutagenic nucleobases such as 5-azacytosine and isoguanine and does not accept natural bases as substrates. Determination of the X-ray structure of Msd to a resolution of 1.9 Å shows that Msd has fine-tuned its active site such that it is a hybrid of a cytosine as well as a guanine deaminase, thereby conferring Msd the ability to expand its repertoire to both purine and pyrimidine-like mutagens. Mapping of active site residues along with X-ray structures with a series of triazine analogues aids in deciphering the mechanism by which Msd proofreads the base milieu for mutagens. The genome location of the enzyme reveals that Msd is part of a conserved cluster that confers the organism with innate resistance toward select xenobiotics by triggering their efflux. PubMed: 28708393DOI: 10.1021/jacs.7b04967 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (1.89 Å) |
Structure validation
Download full validation report
