The biosynthesis of polysaccharides : 4. Plum leaf cellulose

• Published in: Phytochemistry (Oxford) Vol. 4; no. 5; pp. 751 - 757
• Main Authors: Andrews, P., Hough, L., Picken, J.M.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 1965
• ISSN: 0031-9422; 1873-3700
• DOI: 10.1016/S0031-9422(00)86244-5

Detached plum tree spurs were allowed to take up and metabolize 14CO 2, d-glucose-1- 14C and d-glucose-6- 14C and d-glucuronic acid-6- 14C for various periods of time. Incorporation of 14C from 14CO 2 into cellulose continued for at least 40 hr after the supply of isotope to the leaves had ceased. The labelling patterns in d-glucosyl units constituting the cellulose after incorporation of labelled glucoses suggest that units for cellulose synthesis originate from two distinct sources within the leaf, and a structural basis for the location of these sources is proposed. The labelling pattern in d-glucosyl units of cellulose following incorporation of labelled d-glucuronic acid indicates that 14CO 2 arising from decarboxylation of the glucuronate is re-incorporated into hexose within the leaf. The results further suggest that transfer of labelled precursor of high specific activity to the pool providing for cellulose synthesis occurs for only a brief period following the incorporation of labelled compounds by the leaves, so that the precursor's labelling pattern at this time is effectively trapped by its mixing with precursor already in the pool.