In vitro versus in vivo cellulose microfibrils from plant primary wall synthases: Structural differences
2002 (English)In: Journal of Biological Chemistry, ISSN 0021-9258, E-ISSN 1083-351X, Vol. 277, no 40, 36931-36939 p.Article in journal (Refereed) Published
Detergent extracts of microsomal fractions from suspension cultured cells of Rubus fruticosus (blackberry) were tested for their ability to synthesize in vitro sizable quantities of cellulose from UDP-glucose. Both Brij 58 and taurocholate were effective and yielded a substantial percentage of cellulose microfibrils together with (1-->3)-beta-D-glucan (callose). The taurocholate extracts, which did not require the addition of Mg2+, were the most efficient, yielding roughly 20% of cellulose. This cellulose was characterized after callose removal by methylation analysis, electron microscopy, and electron and x-ray synchrotron diffractions; its resistance toward the acid Updegraff reagent was also evaluated. The cellulose microfibrils synthesized in vitro had the same diameter as the endogenous microfibrils isolated from primary cell walls. Both polymers diffracted as cellulose IVI, a disorganized form of cellulose I. Besides these similarities, the in vitro microfibrils had a higher perfection and crystallinity as well as a better resistance toward the Updegraff reagent. These differences can be attributed to the mode of synthesis of the in vitro microfibrils that are able to grow independently in a neighbor-free environment, as opposed to the cellulose in the parent cell walls where new microfibrils have to interweave with the already laid polymers, with the result of a number of structural defects.
Place, publisher, year, edition, pages
2002. Vol. 277, no 40, 36931-36939 p.
beta-glucan synthesis, secondary cell-wall, cotton fiber, enzymatic polymerization, molecular directionality, magnetic-resonance, chitin synthetase, native cellulose, x-ray, biosynthesis
IdentifiersURN: urn:nbn:se:kth:diva-21949ISI: 000178447100005OAI: oai:DiVA.org:kth-21949DiVA: diva2:340647
QC 201005252010-08-102010-08-10Bibliographically approved