Novel bacterial molybdenum and tungsten enzymes: three-dimensional structure, spectroscopy, and reaction mechanism

• Published in: Biological chemistry Vol. 386; no. 10; pp. 999 - 1006
• Main Authors: Boll, Matthias, Schink, Bernhard, Messerschmidt, Albrecht, Kroneck, Peter M.H.
• Format: Journal Article
• Language: English
• Published: Germany Walter de Gruyter 01.10.2005
• Subjects: 4-hydroxybenzoyl-CoA reductase; acetylene hydratase; Bacteria; Bacteria, Anaerobic - enzymology; Bacterial Proteins - chemistry; Bacterial Proteins - metabolism; dithiolene; Enzymes - chemistry; Enzymes - metabolism; hydration; Iron-Sulfur Proteins - chemistry; Iron-Sulfur Proteins - metabolism; Metalloproteins - chemistry; Metalloproteins - metabolism; Molybdenum - chemistry; Protein Conformation; pyrogallol-phloro-glucinol transhydroxylase; reductive dehydroxylation; Spectrum Analysis; transhydroxylation; Tungsten - chemistry
• ISSN: 1431-6730; 1437-4315
• DOI: 10.1515/BC.2005.116

The molybdenum enzymes 4-hydroxybenzoyl-CoA reductase and pyrogallol-phloroglucinol transhydroxylase and the tungsten enzyme acetylene hydratase catalyze reductive dehydroxylation reactions, i.e., transhydroxylation between phenolic residues and the addition of water to a triple bond. Such activities are unusual for this class of enzymes, which carry either a mononuclear Mo or W center. Crystallization and subsequent structural analysis by high-resolution X-ray crystallography has helped to resolve the reaction centers of these enzymes to a degree that allows us to understand the interaction of the enzyme and the respective substrate(s) in detail, and to develop a concept for the respective reaction mechanism, at least in two cases.