Planta

, Volume 155, Issue 6, pp 467–472

Exoglucanases fromZea mays L. seedlings: their role inβ-D-glucan hydrolysis and their potential role in extension growth

Authors

  • Donald J. Huber
    • Vegetable Crops Department, Institute of Food and Agricultural SciencesUniversity of Florida
    • Department of BotanyIowa State University
  • Donald J. Nevins
    • Vegetable Crops Department, Institute of Food and Agricultural SciencesUniversity of Florida
    • Department of BotanyIowa State University
Article

DOI: 10.1007/BF01607569

Cite this article as:
Huber, D.J. & Nevins, D.J. Planta (1982) 155: 467. doi:10.1007/BF01607569

Abstract

Exoglucanases of corn seedlings were examined and evaluated in terms of their participation in the hydrolysis of cell-wall β-D-glucan and their possible role in extension growth. An exo-β-1,3-glucanase (EC 3.2.1.58), a component of the protein dissociated from isolated wall by use of high salt solutions, was purified using gel-filtration and ion-exchange chromatography. The purified enzyme hydrolyzed a number of polymeric and oligosaccharide substrates, including those of mixedlinkage, and their direct conversion to monosaccharide was evidence that the enzyme was capable of hydrolyzing both β1–4 and β1–3 linkages. The enzyme was considerably more active toward glucan that had been previously hydrolyzed by a cell-wall endo-β-D-glucanase. Similarly, the capacity of the purified exo-β-D-glucanase to degrade isolated wall was enhanced by more than 60% when the wall had been previously treated with the endoenzyme. The exo-β-D-glucanase did not exhibit growth-promoting properties nor was its activity, measured in vivo, enhanced by auxin. Another glucanase was obtained from the soluble fraction of seedling homogenates. It functioned strictly as a β-glucosidase and did not appear to participate in the hydrolysis of wall β-D-glucan.

Key words

Cell wall (autolysis)Glucan (β-D)Glucanase (exo-β-D)β-GlucosidaseZea
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Copyright information

© Springer-Verlag 1982