Introducing transglycosylation activity in a liquefying alpha-amylase.
By mutating Ala-289 by Phe or Tyr in the Bacillus stearothermophilus alpha-amylase, we induced this enzyme to perform alcoholytic reactions, a function not present in the wild-type enzyme. This residue was selected from homology analysis with neopullulanase, where the residue has been implicated in the control of transglycosylation [Kuriki et al. (1996) J. Biol. Chem. 271, 17321-173291. We made some inferences about the importance of electrostatic and geometrical modifications in the active site environment of the amylase to explain the behavior of the modified enzyme.
Instituto de Biotecnología, UNAM, Cuernavaca, Morelos, Mexico.
G
G
Saab-Rincón
G
G
del-Río
R I
RI
Santamaría
A
A
López-Munguía
X
X
Soberón
D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D020134:Catalytic Domain; D001411:Geobacillus stearothermophilus / Q000201:enzymology*; D006026:Glycoside Hydrolases / Q000378:metabolism; D006031:Glycosylation; D016695:Glycosyltransferases / Q000235:genetics / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D008958:Models, Molecular; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D016415:Sequence Alignment; D017421:Sequence Analysis; D000516:alpha-Amylases / Q000235:genetics / Q000378:metabolism*
D016695:Glycosyltransferases; D006026:Glycoside Hydrolases; D000516:alpha-Amylases; C058484:neopullulanase