Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
A GLUTAMATE RESIDUE IN THE CATALYTIC CENTER OF THE YEAST CHORISMATE MUTASE RESTRICTS ENZYME-ACTIVITY TO ACIDIC CONDITIONS
Autore:
SCHNAPPAUF G; STRATER N; LIPSCOMB WN; BRAUS GH;
Indirizzi:
UNIV GOTTINGEN,INST MIKROBIOL,GRISEBACHSTR 8 D-37077 GOTTINGEN GERMANY UNIV GOTTINGEN,INST MIKROBIOL D-37077 GOTTINGEN GERMANY HARVARD UNIV,GIBBS CHEM LAB CAMBRIDGE MA 02138
Titolo Testata:
Proceedings of the National Academy of Sciences of the United Statesof America
fascicolo: 16, volume: 94, anno: 1997,
pagine: 8491 - 8496
SICI:
0027-8424(1997)94:16<8491:AGRITC>2.0.ZU;2-4
Fonte:
ISI
Lingua:
ENG
Soggetto:
TRANSITION-STATE ANALOG; BACILLUS-SUBTILIS; SACCHAROMYCES-CEREVISIAE; ESCHERICHIA-COLI; PREPHENATE; MECHANISM; REARRANGEMENT; TRANSFORMATION; EQUILIBRIUM;
Keywords:
CLAISEN REARRANGEMENT; SITE-DIRECTED MUTAGENESIS;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Science Citation Index Expanded
Citazioni:
32
Recensione:
Indirizzi per estratti:
Citazione:
G. Schnappauf et al., "A GLUTAMATE RESIDUE IN THE CATALYTIC CENTER OF THE YEAST CHORISMATE MUTASE RESTRICTS ENZYME-ACTIVITY TO ACIDIC CONDITIONS", Proceedings of the National Academy of Sciences of the United Statesof America, 94(16), 1997, pp. 8491-8496

Abstract

Chorismate mutase acts at the first branchpoint of aromatic amino acid biosynthesis and catalyzes the conversion of chorismate to prephenate, Comparison of the x-ray structures of allosteric chorismate mutase from the yeast Saccharomyces cerevisiae with Escherichia coli chorismate mutase/prephenate dehydratase suggested conserved active sites between both enzymes, We have replaced all critical amino acid residues, Arg-16, Arg-157, Lys-168, Glu-198, Thr-242, and Glu-246, of yeast chorismate mutase by aliphatic amino acid residues, The resulting enzymes exhibit the necessity of these residues for catalytic function and provide evidence of their localization at the active site, Unlike some bacterial enzymes, yeast chorismate mutase has highest activity at acidicpH values, Replacement of Glu-246 in the yeast chorismate mutase by glutamine changes the pH optimum for activity of the enzyme from a narrow to a broad pH range, These data suggest that Glu-246 in the catalytic center must be protonated for maximum catalysis and restricts optimal activity of the enzyme to low pH.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 08/07/20 alle ore 07:54:33