title: 4-hydroxyphenylpyruvate dioxygenase catalysis: identification of catalytic residues and production of a hydroxylated intermediate shared with a structurally unrelated enzyme.
abstract: 4-Hydroxyphenylpyruvate dioxygenase (HPPD) catalyzes the conversion of 4-hydroxyphenylpyruvate (HPP) into homogentisate. HPPD is the molecular target of very effective synthetic herbicides. HPPD inhibitors may also be useful in treating life-threatening tyrosinemia type I and are currently in trials for treatment of Parkinson disease. The reaction mechanism of this key enzyme in both plants and animals has not yet been fully elucidated. In this study, using site-directed mutagenesis supported by quantum mechanical/molecular mechanical theoretical calculations, we investigated the role of catalytic residues potentially interacting with the substrate/intermediates. These results highlight the following: (i) the central role of Gln-272, Gln-286, and Gln-358 in HPP binding and the first nucleophilic attack; (ii) the important movement of the aromatic ring of HPP during the reaction, and (iii) the key role played by Asn-261 and Ser-246 in C1 hydroxylation and the final ortho-rearrangement steps (numbering according to the Arabidopsis HPPD crystal structure 1SQD). Furthermore, this study reveals that the last step of the catalytic reaction, the 1,2 shift of the acetate side chain, which was believed to be unique to the HPPD activity, is also catalyzed by a structurally unrelated enzyme.
authors: Université Joseph Fourier, France.
authors: Corinne
authors: C
authors: Raspail
authors: Matthieu
authors: M
authors: Graindorge
authors: Yohann
authors: Y
authors: Moreau
authors: Serge
authors: S
authors: Crouzy
authors: Bertrand
authors: B
authors: Lefèbvre
authors: Adeline Y
authors: AY
authors: Robin
authors: Renaud
authors: R
authors: Dumas
authors: Michel
authors: M
authors: Matringe
references: Anal Biochem. 1974 May;59(1):277-82
references: 4407487
references: Proc Natl Acad Sci U S A. 1977 Oct;74(10):4641-5
references: 270706
references: Biochemistry. 2004 Jun 1;43(21):6370-7
references: 15157070
references: FEBS Lett. 1993 Mar 1;318(2):162-6
references: 8382628
references: Biochemistry. 2000 Jun 27;39(25):7501-7
references: 10858299
references: Phys Rev A Gen Phys. 1988 Sep 15;38(6):3098-3100
references: 9900728
references: J Biol Chem. 1977 Jul 25;252(14):5094-9
references: 873933
references: Proc Natl Acad Sci U S A. 2006 Aug 29;103(35):12966-73
references: 16920789
references: Biochemistry. 2004 Jan 27;43(3):663-74
references: 14730970
references: Arch Biochem Biophys. 1980 Oct 15;204(2):544-50
references: 7447462
references: Structure. 1999 Aug 15;7(8):977-88
references: 10467142
references: Plant Physiol. 1994 Dec;106(4):1429-1433
references: 12232420
references: J Bacteriol. 1975 Jan;121(1):272-85
references: 234937
references: Science. 1967 Sep 29;157(3796):1524-30
references: 6038165
references: Biochemistry. 2004 Aug 17;43(32):10414-23
references: 15301540
references: FEBS Lett. 2000 Sep 1;480(2-3):301-5
references: 11034349
references: J Mol Biol. 1976 May 15;103(2):227-49
references: 985660
references: Anal Biochem. 1976 May 7;72:248-54
references: 942051
references: Chem Rev. 2000 Jan 12;100(1):235-350
references: 11749238
references: Pest Manag Sci. 2005 Mar;61(3):269-76
references: 15633191
references: Toxicol Appl Pharmacol. 1995 Jul;133(1):12-9
references: 7597701
references: Lancet. 1992 Oct 3;340(8823):813-7
references: 1383656
references: Biochemistry. 2004 Sep 28;43(38):12331-42
references: 15379572
references: Phys Rev B Condens Matter. 1988 Jan 15;37(2):785-789
references: 9944570
references: Biochem J. 1974 Aug;142(2):437-40
references: 4374200
references: Biochemistry. 2003 Feb 25;42(7):2072-80
references: 12590595
references: Plant Physiol. 1999 Apr;119(4):1507-16
references: 10198110
references: Plant Physiol. 2004 Apr;134(4):1388-400
references: 15084729
references: Biochemistry. 1985 Jun 18;24(13):3158-65
references: 4027238
references: Pediatr Res. 1983 Feb;17(2):92-6
references: 6828337
references: Clin Chim Acta. 1978 Dec 1;90(2):195-200
references: 719903
references: Mol Genet Metab. 2000 Nov;71(3):506-10
references: 11073718
references: Biochemistry. 2008 Feb 19;47(7):2002-13
references: 18215022
references: J Am Chem Soc. 2003 Jun 11;125(23):6868-9
references: 12783530