Abstract
High concentrations of water-soluble carbohydrates, mainly fructan, accumulate in the growth zone of tall fescue (Festuca arundinacea Schreb.) leaf blades. We studied sucrose-hydrolyzing activities in the leaf growth zone because of their importance in carbohydrate partitioning. Sucrose hydrolysis in the basal 1.5 cm was largely due to fructosyltransferases, which had activities up to 10 times higher than in fully developed leaf tissue. Three fructosyltransferases (F1, F2, and F3) were purified from the leaf growth zone. Each synthesized, from either sucrose or 1-kestose, a mixture of trisaccharides and higher-order oligofructans identical with the low-degree of polymerization fructan extracted from similar plant tissue. The highly purified fructosyltransferases retained ability (13%) to transfer fructose from sucrose to water. Time-dependent and substrate-dependent studies, using sucrose as the substrate, showed proportional production of fructose and glucose, indicating that both products are from the same enzyme. Fructosyltransferase was calculated to contribute about half the total transfer of fructose to water in the basal 1.5 cm. Invertase activity increased to near 2.0 cm when fructosyl transfer to sucrose and other oligofructans decreased. Invertase was the major activity for sucrose hydrolysis at positions distal to 3.0 cm.
Full Text
The Full Text of this article is available as a PDF (1.6 MB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Allard G., Nelson C. J. Photosynthate partitioning in Basal zones of tall fescue leaf blades. Plant Physiol. 1991 Mar;95(3):663–668. doi: 10.1104/pp.95.3.663. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bradford M. M. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem. 1976 May 7;72:248–254. doi: 10.1016/0003-2697(76)90527-3. [DOI] [PubMed] [Google Scholar]
- Gabriel O., Wang S. F. Determination of enzymatic activity in polyacrylamide gels. I. Enzymes catalyzing the conversion of nonreducing substrates to reducing products. Anal Biochem. 1969 Mar;27(3):545–554. doi: 10.1016/0003-2697(69)90068-2. [DOI] [PubMed] [Google Scholar]
- Jeong B. R., Housley T. L. Purification and Characterization of Wheat beta(2-->1) Fructan:Fructan Fructosyl Transferase Activity. Plant Physiol. 1992 Sep;100(1):199–204. doi: 10.1104/pp.100.1.199. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
- Macadam J. W., Volenec J. J., Nelson C. J. Effects of nitrogen on mesophyll cell division and epidermal cell elongation in tall fescue leaf blades. Plant Physiol. 1989 Feb;89(2):549–556. doi: 10.1104/pp.89.2.549. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Obenland D. M., Simmen U., Boller T., Wiemken A. Purification and characterization of three soluble invertases from barley (Hordeum vulgare L.) leaves. Plant Physiol. 1993 Apr;101(4):1331–1339. doi: 10.1104/pp.101.4.1331. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schnyder H., Nelson C. J. Growth Rates and Carbohydrate Fluxes within the Elongation Zone of Tall Fescue Leaf Blades. Plant Physiol. 1987 Oct;85(2):548–553. doi: 10.1104/pp.85.2.548. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schnyder H., Nelson C. J. Growth rates and assimilate partitioning in the elongation zone of tall fescue leaf blades at high and low irradiance. Plant Physiol. 1989 Jul;90(3):1201–1206. doi: 10.1104/pp.90.3.1201. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Simmen U., Obenland D., Boller T., Wiemken A. Fructan Synthesis in Excised Barley Leaves (Identification of Two Sucrose-Sucrose Fructosyltransferases Induced by Light and Their Separation from Constitutive Invertases). Plant Physiol. 1993 Feb;101(2):459–468. doi: 10.1104/pp.101.2.459. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Spollen W. G., Nelson C. J. Characterization of fructan from mature leaf blades and elongation zones of developing leaf blades of wheat, tall fescue, and timothy. Plant Physiol. 1988 Dec;88(4):1349–1353. doi: 10.1104/pp.88.4.1349. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Spollen W. G., Nelson C. J. Response of Fructan to Water Deficit in Growing Leaves of Tall Fescue. Plant Physiol. 1994 Sep;106(1):329–336. doi: 10.1104/pp.106.1.329. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Straathof A. J., Kieboom A. P., van Bekkum H. Invertase-catalysed fructosyl transfer in concentrated solutions of sucrose. Carbohydr Res. 1986 Jan 15;146(1):154–159. doi: 10.1016/0008-6215(86)85033-9. [DOI] [PubMed] [Google Scholar]