Insights into the Mechanistic Pathway of the Pantoea agglomerans Phenylalanine Aminomutase


  • We thank the Department of Energy, Office of Science, Basic Energy Sciences, Chemical Sciences, Geosciences and Biosciences Division (DE-FG02-06ER15822 to J.H.G.) and the National Science Foundation (CAREER Award 0746432 to K.D.W.) for financial support, and acknowledge Prof. Christopher Walsh, Harvard Medical School, for providing the cDNA clone encoding AdmH (PaPAM).


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The structure of the title aminomutase has been solved. The steric bulk of Phe 455 (green CPK structure) twists the phenylpropanoate ligand (green stick) by approximately 15° about the Cβ axis, which precludes a stronger bidentate salt bridge with Arg 323 (magenta structure). Instead, a weaker monodentate bridge may partially explain the different configuration of the product, relative to that obtained with an isoenzyme that forms a bidentate intermediate.