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Publication Abstract from PubMed

Ethylenediaminetetraacetate (EDTA) is currently the most abundant organic pollutant due to its recalcitrance and extensive use. Only a few bacteria can degrade it, using EDTA monooxygenase (EmoA) to initiate the degradation. EmoA is an FMNH2 -dependent monooxygenase that requires an NADH:FMN oxidoreductase (EmoB) to provide FMNH2 as a cosubstrate. Although EmoA has been identified from Chelativorans (ex. Mesorhizobium) sp. BNC1, its catalytic mechanism is unknown. Crystal structures of EmoA revealed a domain-like insertion into a TIM-barrel, which might serve as a flexible lid for the active site. Docking of MgEDTA2- into EmoA identified an intricate hydrogen bond network connected to Tyr71 , which should potentially lower its pKa. Tyr71 , along with nearby Glu70 and a peroxy flavin, facilitates a keto-enol transition of the leaving acetyl group of EDTA. Further, for the first time, the physical interaction between EmoA and EmoB was observed by ITC, molecular docking and enzyme kinetic assay, which enhanced both EmoA and EmoB activities probably through coupled channeling of FMNH2 . This article is protected by copyright. All rights reserved.

Structural and Biochemical Characterization of EDTA Monooxygenase and its Physical Interaction with a Partner Flavin Reductase.,Jun SY, Lewis KM, Youn B, Xun L, Kang C Mol Microbiol. 2016 Feb 29. doi: 10.1111/mmi.13363. PMID:26928990^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.