A specific enzyme hydrolyzing 6-O(4-O)-indole-3-ylacetyl-beta-D-glucose in immature kernels of Zea mays.
The purification of 6-O(4-O)-indole-3-ylacetyl-beta-D-glucose (IAGlc) hydrolase from immature kernels of maize (Zea mays) was undertaken to separate this enzyme from 1-O-IAGlc hydrolase and beta-glucosidase. Partially purified 6-O(4-O)-IAGlc hydrolase was found to be the specific enzyme catalyzing hydrolysis of stable esters of IAA and glucose. Among a range of ester conjugates tested as substrates, only 6-O(4-O)-IAA-glucose and IBA-glucose isomers were effectively hydrolyzed. No activity against p-nitrophenyl-beta-D-glucopyranoside, a synthetic substrate for beta-glucosidase, was detected in the enzyme preparation. The enzyme is probably involved in the regulation of the IAA levels by the target release of free auxin from ester-linked conjugates, its inactive storage forms.
Jakubowska
Anna
A
Department of Biochemistry, Institute of General and Molecular Biology, Nicolaus Copernicus University, ul Gagarina 9, 87-100 Toruń, Poland. anjakubo@uni.torun.pl
Kowalczyk
Stanisław
S
D005947:Glucose / Q000031:analogs & derivatives / Q000378:metabolism; D005960:Glucosides / Q000378:metabolism*; D006867:Hydrolases / Q000302:isolation & purification* / Q000378:metabolism*; D007210:Indoleacetic Acids / Q000378:metabolism; D007211:Indoles / Q000378:metabolism*; D012639:Seeds / Q000201:enzymology*; D013379:Substrate Specificity; D003313:Zea mays / Q000201:enzymology*; D001617:beta-Glucosidase / Q000378:metabolism
C500670:6-O(4-O)-indole-3-ylacetyl-beta-D-glucose; D005960:Glucosides; D007210:Indoleacetic Acids; D007211:Indoles; C037009:1-O-indol-3-ylacetylglucose; D006867:Hydrolases; D001617:beta-Glucosidase; D005947:Glucose