Cellulose in the cyanobacteria

textMultiple aspects of cellulose biosynthesis in cyanobacteria were investigated: product identification and characterization; function, sequence and phylogenetic analyses of the cellulose synthases; suitability of cyanobacteria for transgenic cellulose synthase expression; and improved tools for the detection and identification of product. Cellulose was positively identified in members of three sections of cyanobacteria. Sequence and phylogenetic analyses established a cyanobacterial origin of vascular plant cellulose synthases. An insertional knockout of a plant-like cellulose synthase caused a loss of heterocyst envelope birefringence, altered the homogeneous polysaccharide layer of the heterocyst, and impaired nitrogen fixation in Nostoc punctiforme. Mutants of Synechococcus leopoliensis strain UTCC 100 expressing genes from the cellulose synthase operon of Acetobacter xylinum secreted extracellular material, which bound Tinopal and CBHI-gold, but could not be positively identified as cellulose. Finally, specific β 1,4-glucan probes for use in fluorescence and electron microscopy were successfully created by fusing the cellulose binding module of Trametes hirsuta to Green Fluorescent Protein (GFP) and Ferritin (FtnA), respectively.Biological Sciences, School o