Publication no. C-2003-0211-01R |  VIEW ARTICLE

Aryl-Glycosidase Activities in Germinating Maize.

Peter Biely (1), Jeffrey A. Ahlgren (2,3), Timothy D. Leathers (2,4), Richard V. Greene (5), and Michael A. Cotta (2). (1) Institute of Chemistry, Slovak Academy of Sciences, Bratislava, Slovak Republic. (2) Fermentation Biotechnology Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, USDA, Peoria, IL 61604. Names are necessary to report factually on available data; however, the USDA neither guarantees nor warrants the standard of the product, and the use of the name by the USDA implies no approval of the product to the exclusion of others that may also be suitable. (3) Current address: Wyatt Technology Corp., Santa Barbara, CA 93117. (4) Corresponding author. Phone: 309-681-6377. Fax: 309-681-6427. E-mail: <leathetd@ncaur.usda.gov> (5) Office of International Programs, Agricultural Research Service, USDA, Beltsville, MD 20705. Cereal Chem. 80(2):144-147. Accepted September 27, 2002. This article is in the public domain and not copyrightable. It may be freely reprinted with customary crediting of the source. American Association of Cereal Chemists, Inc., 2003.

Soluble protein extracts of germinating maize seedlings exhibited a limited ability to hydrolyze purified xylans, and specific assays were unable to confirm the presence of endo-beta-1,4-xylanase activity. However, extracts contained a variety of aryl-glycosidase activities, including beta-glucosidase, beta-xylosidase, and alpha-L-arabinofuranosidase. These activities peaked in three- to four-day seedlings and were particularly concentrated in shoot and root tissues. Maximal levels of beta-glucosidase were two orders of magnitude greater than those of beta-xylosidase or alpha-L-arabinofuranosidase. Isoelectric focusing gels revealed multiple forms of these enzymes. The principal beta-glucosidase and alpha-L-arabinofuranosidase protein species were clustered at pI 4.8-4.9 and pI 5.8-6.0, respectively. beta-Xylosidase activity appeared to be associated with both of these enzymes, and no evidence was obtained for a distinct beta-xylosidase.