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Microfibril structure is determined largely by the organization of arrays of integral plasma membrane protein particles known as “terminal complexes”, which include cellulose synthase catalytic subunits encoded by CesA genes. Although the CesA genes of plants and bacteria share conserved regions, variations in terminal complex and microfibril structure presumably result from sequence differences....
Use of pyrolytic carbon from cellulose has been limited in practice to activated adsorbent carbon, but cellulose-derived carbon retaining the nanoscale microfibrillar morphology offers rich possibilities as an advanced material. Here we developed novel methods to prepare such materials by an improved drying of wet cellulose prior to pyrolysis. This procedure is an adaptation from electron microscopy...
Cellulose synthase (CESA) molecules are the building blocks and catalytic centers of the CESA complex. The study of mutants in Arabidopsis has led to insight into the structure of these nanomachines. Inside the plasma membrane, the CESA molecules are arranged in complexes, which, apart from the CESA molecules proper, contain other, mostly unidentified, proteins. We developed a theory in which CESA...
Cellulose is synthesized in plant cell walls by large membrane-bound protein complexes proposed to contain several copies of the catalytic subunit of the cellulose synthase, CesA. Here we report identification of 10 distinct CesA genes within a database of 100,000 ESTs of the hybrid aspen, Populus tremula (L.) × P. tremuloides (Michx.). Expression analyses in normal wood undergoing xylogenesis and...
We proposed in a previous paper a unique form of β-glucan association, nematic ordered cellulose (NOC) that is molecularly ordered, yet non-crystalline. NOC has unique characteristics; in particular, its surface properties provide with a function of tracks or scaffolds for regulated movements and fiber-production of Acetobacter xylinum [Kondo et al. 2002. Proc. Natl. Acad. Sci. USA 99: 14008–14013]...
The aim of this work was to optimize the conditions for in vitro synthesis of (1→3)-β-D-glucan (callose) and cellulose, using detergent extracts of membranes from hybrid aspen (Populus tremula ×tremuloides) cells grown as suspension cultures. Callose was the only product synthesized when CHAPS extracts were used as a source of enzyme. The optimal reaction mixture for callose synthesis contained 100...
Distinct bacterial species belonging to the family of enterobacteriaceae produce cellulose as an exopolysaccharide. Cellulose produced by Salmonella enterica serovar Typhimurium was isolated by various methods. Subsequently, transmission electron microscopy (TEM) studies of the isolated material revealed novel structural details of enterobacterial cellulose.
Freeze fracture investigations have been carried out to investigate cellulose-synthesizing terminal complexes (TCs) in some chromophyte algae. The xanthophycean alga Botrydiopsis intercedens has TCs that consist of 3–8 diagonal rows of particles in the PF of the plasma membrane. A new type of TC was found in the phaeothamniophycean algae Phaeoschizochlamys mucosa, Phaeothamnion confervicola and Stichogloea doederleinii...
Cellulose-deficient Arabidopsis mutants were identified using FT-IR microspectroscopy. The study of these mutants not only led to the identification of actors in cellulose synthesis, but also provided insights in the organization of the hexameric terminal complex from CESA mutants and identified unsuspected accessory proteins with so far unknown roles in the synthesis and/or assembly of cellulose...
Stalk lodging in maize results in significant yield losses. We have determined that cellulose per unit length of the stalk is the primary determinant of internodal strength. An increase in cellulose concentration in the wall might allow simultaneous improvements in stalk strength and harvest index. Cellulose formation in plants can be perturbed by mutations in the genes involved in cellulose synthesis,...
Structural characteristics of microbial cellulose synthesized by two different methods have been compared using FT-IR and X-ray diffraction techniques. Cellulose synthesized by Acetobacter xylinum NQ-5 strain from agitated culture conditions is characterized by a lower Iϑ mass fraction than cellulose that was produced statically. Such a decrease was in good correlation with smaller crystallite sizes...
We have used Affymetrix gene chips to measure the expression of 10 CESA and 29 CSL genes of Arabidopsis in different developmental stages or organs. These measurements reveal that many of the genes exhibit different levels of expression in the various organs. While several CESA genes are highly expressed in all the tissues examined, very few CSL genes approach such high levels of expression. This...
Energy surfaces imply which molecular shapes are more likely and which are less likely. Therefore, they are valuable for assisting the understanding of the structures involved in biosynthesis and many practical post-harvest exploitations of cellulose. Although usually calculated with molecular mechanics, energy surfaces for the cellobiose fragment of cellulose can now be based on quantum mechanics...
Cellulose synthase and other members of the family 2 glycosyltransferases are ubiquitous in all kingdoms of life. To date, no attempt has been made to construct a phylogeny that positions cellulose synthases in relation to other members of this family or to elucidate relationships within the cellulose synthase group. In this study, a sequence from the unicellular, marine cyanobacterium Synechococcus...
The sodium dodecyl sulfate (SDS)-solubilized freeze fracture replica labeling (SDS-FRL) technique has been successfully applied to a vascular plant, Vigna angularis [Kimura et al. 1999, Plant Cell 11: 2075–2085] and a bacterium, Acetobacter xylinum [Kimura et al. 2001, J. Bacteriol. 183: 5668–5674] for understanding cellulose biosynthesis. However, we do not know yet how many gold particles can be...
Current knowledge about the integration of cellulose synthesis into cellular carbon metabolism and the cool temperature sensitivity of cellulose synthesis is reviewed briefly. Roles for sucrose synthase (to channel UDP-glucose to the cellulose synthase) and sucrose phosphate synthase (to recycle the fructose released by sucrose synthase to more sucrose) in secondary wall cellulose synthesis are described...
The structure of cellulose synthesizing terminal complexes (TCs) has been investigated in different species of ascidians. The linear-shaped TCs consisting of two types of membrane particles were found in four species belonging to two orders including previous data . A relationship between the length of TCs and the size of produced cellulose microfibrils was found within the same order. The density...
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