Valonia cellulose microscopy

Baker AA, Helbert W. Sugiyama J, Miles MJ. High-resolution atomic force microscopy of native Valonia cellulose I. Microcrystals. J Struct Biol 1997 119 129-138. 

Valonia cellulose I was peracetylated under nonswelling conditions. The observations made by electron microscopy and electron diffraction on the fibrous tri-O-acetylcellulose I (CTA I) and the cellulose I obtained by deacetylation thereof led to the conclusion that the chains in CTA I are parallel-packed, as in cellulose I. Similar experiments showed that CTA II and cellulose II have the same antiparallel polarity of the chains in the lattice. 

Mercerization of fibrous Valonia cellulose has been achieved with aqueous ethanolic sodium hydroxide and the course of mercerization was monitored by electron microscopy. The production of single-cell proteins from cellulosic wastes has been described. ... 

Although one can have a broad picture of how Type A function comes about, the detailed kinetics and thermodynamics still present unsolved problems. The planar, hydrophobic, aromatic face presented by all the protein folds that have Type A function suggests that the driving force is hydrophobic and that therefore Type A CBDs should bind preferentially to hydrophobic faces of the polysaccharide crystal. Indeed, with gold-labelled CBM 1 and CBM 3 binding to cellulose lo, (triclinic) crystals of Valonia ventricosa, electron microscopy reveals just that - preferential binding to the (110) face of the crystal. 

Fig. 44. Microciystals of Valonia macrophysa cellulose subjected to the action of celluloses (CeI7A from Humicola insolens) consisting of a hydrolytic core, a cellulose-binding module, and a linker that binds the two enzymic components. The reducing end of the cellulose chains is indicated. R, transmission electron microscopy of the cellulose microciystals before and after the enzyme aetion indieates that Cel7A induced a...

H. Chanzy, B. Heiuissat, M. Vincendon, S. Tanner, and P. B. Belton, Solid-state C-NMR and electron microscopy study on the reversible cellulose I —> cellulose nil transformation in Valonia, Carbohydr. Res., 160 (1987) 1-11. 

E. Roche and H. Chanzy, Electron microscopy study of the transformation of cellulose I into cellulose Ilh in Valonia, Int. J. Biol. Macromol, 3 (1981) 201-206. 

Crystals of ivory nut D-mannan have been grown on microfibrils from Valonia sp. cellulose. These crystals were in the form of perpendicularly orientated lamellae with widths of ca. 10 A as revealed by electron microscopy. The structure has been designated a shish-kebab type structure. Precipitation of the D-mannan on beaten softwood pulp fragments also gave shish-kebab type structures, indicating that the cellulosic fibre cell wall is a good substrate for orientated crystallization of D-mannan. 

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