4CQD

The reaction mechanism of the N-isopropylammelide isopropylaminohydrolase AtzC: insights from structural and mutagenesis studies

Summary for 4CQD

• Entry DOI: 10.2210/pdb4cqd/pdb
• Related: 4CQB 4CQC
• Descriptor: N-ISOPROPYLAMMELIDE ISOPROPYL AMIDOHYDROLASE, ZINC ION, 2-(N-MORPHOLINO)-ETHANESULFONIC ACID, ... (6 entities in total)
• Functional Keywords: hydrolase, atrazine breakdown
• Biological source: PSEUDOMONAS SP. ADP
• Cellular location: Cytoplasm : O52063
• Total number of polymer chains: 2
• Total formula weight: 94999.48

Authors

Balotra, S.,Newman, J.,French, N.G.,Peat, T.S.,Scott, C. (deposition date: 2014-02-13, release date: 2015-03-04, Last modification date: 2023-12-20)

Primary citation

Balotra, S.,Warden, A.C.,Newman, J.,Briggs, L.J.,Scott, C.,Peat, T.S.
X-Ray Structure and Mutagenesis Studies of the N-Isopropylammelide Isopropylaminohydrolase, Atzc
Plos One, 1:37700-, 2015

PubMed Abstract: The N-isopropylammelide isopropylaminohydrolase from Pseudomonas sp. strain ADP, AtzC, provides the third hydrolytic step in the mineralization of s-triazine herbicides, such as atrazine. We obtained the X-ray crystal structure of AtzC at 1.84 Å with a weak inhibitor bound in the active site and then used a combination of in silico docking and site-directed mutagenesis to understand the interactions between AtzC and its substrate, isopropylammelide. The substitution of an active site histidine residue (His249) for an alanine abolished the enzyme's catalytic activity. We propose a plausible catalytic mechanism, consistent with the biochemical and crystallographic data obtained that is similar to that found in carbonic anhydrase and other members of subtype III of the amidohydrolase family.

PubMed: 26390431
DOI: 10.1371/JOURNAL.PONE.0137700

Experimental method

X-RAY DIFFRACTION (2.25 Å)