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Title: Differential scanning calorimetry of plant cell walls

Abstract

High-sensitivity differential scanning calorimetry has been used to study the phase transition of cell wall preparations of the elongating and mature regions of soybean hypocotyls and of celery epidermis and collenchyma strands. A step-like transition believed to be glass transition was observed in walls isolated from the elongating region of soybean hypocotyls at 52.9C. Addition of 1 mM CaCl{sub 2} to the cell wall preparation increased the transition temperature to 60.8C and greatly reduced the transition magnitude. In walls from the mature region, the transition was small and occurred at a higher temperature (60.1C). Addition of calcium to the mature region cell wall had little effect on the transition. Based on the known interactions between calcium and pectin, the authors propose that calcium affects the glass transition by binding to the polygalacturonate backbone of wall pectin, resulting in a more rigid wall with a smaller transition at a higher temperature. The mature region either has more calcium in the wall or has more methyl-esterified pectin, making it less responsive to added calcium.

Authors:
;  [1];  [2]
  1. (Washington Univ., St. Louis, MO (United States))
  2. (Monsanto Co., St. Louis, MO (United States))
Publication Date:
OSTI Identifier:
5078163
DOE Contract Number:
FG02-84ER13255
Resource Type:
Journal Article
Resource Relation:
Journal Name: Proceedings of the National Academy of Sciences of the United States of America; (United States); Journal Volume: 88:6
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; CELL WALL; PHASE STUDIES; PLANT CELLS; DIFFERENTIAL THERMAL ANALYSIS; CALCIUM CHLORIDES; CALORIMETRY; PECTINS; SOYBEANS; ALKALINE EARTH METAL COMPOUNDS; BLOOD SUBSTITUTES; CALCIUM COMPOUNDS; CALCIUM HALIDES; CARBOHYDRATES; CELL CONSTITUENTS; CHLORIDES; CHLORINE COMPOUNDS; DRUGS; FOOD; HALIDES; HALOGEN COMPOUNDS; HEMATOLOGIC AGENTS; ORGANIC COMPOUNDS; PLANTS; POLYSACCHARIDES; SACCHARIDES; THERMAL ANALYSIS; VEGETABLES; 550300* - Cytology

Citation Formats

Lin, Liangshiou, Varner, J.E., and Yuen, H.K. Differential scanning calorimetry of plant cell walls. United States: N. p., 1991. Web. doi:10.1073/pnas.88.6.2241.
Lin, Liangshiou, Varner, J.E., & Yuen, H.K. Differential scanning calorimetry of plant cell walls. United States. doi:10.1073/pnas.88.6.2241.
Lin, Liangshiou, Varner, J.E., and Yuen, H.K. 1991. "Differential scanning calorimetry of plant cell walls". United States. doi:10.1073/pnas.88.6.2241.
@article{osti_5078163,
title = {Differential scanning calorimetry of plant cell walls},
author = {Lin, Liangshiou and Varner, J.E. and Yuen, H.K.},
abstractNote = {High-sensitivity differential scanning calorimetry has been used to study the phase transition of cell wall preparations of the elongating and mature regions of soybean hypocotyls and of celery epidermis and collenchyma strands. A step-like transition believed to be glass transition was observed in walls isolated from the elongating region of soybean hypocotyls at 52.9C. Addition of 1 mM CaCl{sub 2} to the cell wall preparation increased the transition temperature to 60.8C and greatly reduced the transition magnitude. In walls from the mature region, the transition was small and occurred at a higher temperature (60.1C). Addition of calcium to the mature region cell wall had little effect on the transition. Based on the known interactions between calcium and pectin, the authors propose that calcium affects the glass transition by binding to the polygalacturonate backbone of wall pectin, resulting in a more rigid wall with a smaller transition at a higher temperature. The mature region either has more calcium in the wall or has more methyl-esterified pectin, making it less responsive to added calcium.},
doi = {10.1073/pnas.88.6.2241},
journal = {Proceedings of the National Academy of Sciences of the United States of America; (United States)},
number = ,
volume = 88:6,
place = {United States},
year = 1991,
month = 3
}
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