TitleComparison of CryoEM and X-ray structures of dimethylformamidase.
Publication TypeJournal Article
Year of Publication2020
AuthorsVinothkumar KR, Arya C, Ramanathan G, Subramanian R
JournalProg Biophys Mol Biol
Date Published2020 Jul 28

Dimethylformamidase (DMFase) catalyzes the hydrolysis of dimethylformamide, an industrial solvent, introduced into the environment by humans. Recently, we determined the structures of dimethylformamidase by electron cryo microscopy and X-ray crystallography revealing a tetrameric enzyme with a mononuclear iron at the active site. DMFase from Paracoccus sp. isolated from a waste water treatment plant around the city of Kanpur in India shows maximal activity at 54 °C and is halotolerant. The structures determined by both techniques are mostly identical and the largest difference is in a loop near the active site. This loop could play a role in co-operativity between the monomers. A number of non-protein densities are observed in the EM map, which are modelled as water molecules. Comparison of the structures determined by the two methods reveals conserved water molecules that could play a structural role. The higher stability, unusual active site and negligible activity at low temperature makes this a very good model to study enzyme mechanism by cryoEM.

Alternate JournalProg. Biophys. Mol. Biol.
PubMed ID32735943