Characterization of pocket galls formed by an aphid on Distylium racemosum leaves.

2006 Fiscal Year Final Research Report Summary

• Project/Area Number: 16580274
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Boundary agriculture
• Research Institution: Okayama University
• Principal Investigator: KONNO Haruyoshi Research Institute for Bioresources, Associate Professor, 資源生物科学研究所, 助教授 (10108178)
• Co-Investigator(Kenkyū-buntansha): NAKASHIMA Susumu Research Iistitute for Bioresources, Associate Professor, 資源生物科学研究所, 助教授 (60033122) ; TSUMUKI Hisaaki Research Institute for Bioresources, Professor, 資源生物科学研究所, 教授 (60033255)
• Project Period (FY): 2004 – 2006
• Keywords: Distylium racemosum / insect gall / Distylium callus / plant cell wall / glycosyl-hydrolase / aphid

Research Abstract

This work investigated the isolation and characterization of the matrix polysaccharides in cell walls from the healthy leaf, gall, and callus of Distylium racemosum. The leaf cell walls consisted mainly of arabinose, xylose, glucose, and uronic acids, whereas the gall and callus cell walls consisted of arabinose, xylose, galactose, and uronic acids. Pectin solubilized from leaf, gall, and callus cell walls accounted for 3%, 7%, and 16%, respectively, of cell wall dry weight, whereas hemicellulose was solubilized 24% from depectinated cell walls of gall and callus. When the matrix polysaccharides were fractionated by anion-exchange chromatography, the hemicellulosic polymers of the gall and callus cell walls exhibited distinctly different elution patterns, compared with the leaf cell walls. A considerable difference in hemicellulose of the gall and callus cell walls as compared with leaf cell walls could be a consequence of a defect in arabinoxylan of cell wall structure.
Further many of the glycosyl-hydrolase activities were detected in the protein fractions solubilized with the buffer and the strong saline solution from leaf, gall, and callus. The β-galactosidase was purified from a protein fraction soluble in the buffer of callus cells and the purified enzyme was characterized with respect to the enzymatic properties such as molecular mass, isoelectric point, pH profile of activity and stability, temperature profile of activity and stability, inhibitors, and kinetic constant.