Kinetics of the Biosynthesis of Cellulose in Cotton Bolls by Different Light Intensities

PREVIOUS kinetic investigations of the biosynthesis of cellulose in higher plants suggested that the secondary wall cellulose is synthesized by a structure-controlled mechanism (template mechanism)1–5. In order to confirm my assumption I changed the reaction rate by varying the intensity of illumination of the cotton plants. Cotton plants (Gossypium herbaceum) were grown in a glass-house at a mean temperature of 25° C (the night temperatures never were less than 18° C). The intensity of illumination amounted to 4,000, 15,000 and 60,000 lux respectively (mean values). The time of maturity was calculated from the time the flowers were fertilized. Bolls of different maturities were picked, imm…

On the biosynthesis of cellulose in higher and lower plants

Kinetic experiments on cotton cellulose and cellulose from the alga Valonia show, that the degree of polymerization during the biosynthesis of the secondary wall is independent of conversion and reaction conditions. During the whole synthesis period it remains constant at a DPw ∼ 13,000 for cotton and 16,500 for Valonia, respectively. Fractionation experiments indicate complete uniformity of the degree of polymerization at every stage of the biosynthesis. This means that the biosynthesis of secondary wall cellulose for both higher and lower plants must be a structure-controlled process and not a time-controlled one. Contrary to this evidence the synthesis of primary wall cellulose takes pla…

Zur Biosynthese der Cellulose

Comparison of the Biosynthesis of Cellulose in vitro and in vivo in Cotton Bolls

THE work of Hassid et al.1–3 on the cell-free synthesis of cellulose with an enzyme system isolated from mung bean seedlings and young cotton bolls has shown that the enzyme is apparently unable to distinguish guanosine diphosphate-D-glucose from guanosine diphosphate-D-mannose. Moreover, there was a notable decrease in the amount of the synthesized cellulose using enzymes from cotton bolls older than 15 days.