Cellulose in Cyanobacteria. Origin of Vascular Plant Cellulose Synthase?

Abstract

Although cellulose biosynthesis among the cyanobacteria has been suggested previously, we present the first conclusive evidence, to our knowledge, of the presence of cellulose in these organisms. Based on the results of x-ray diffraction, electron microscopy of microfibrils, and cellobiohydrolase I-gold labeling, we report the occurrence of cellulose biosynthesis in nine species representing three of the five sections of cyanobacteria. Sequence analysis of the genomes of four cyanobacteria revealed the presence of multiple amino acid sequences bearing the DDD35QXXRW motif conserved in all cellulose synthases. Pairwise alignments demonstrated that CesAs from plants were more similar to putative cellulose synthases from Anabaena sp. Pasteur Culture Collection 7120 and Nostoc punctiforme American Type Culture Collection 29133 than any other cellulose synthases in the database. Multiple alignments of putative cellulose synthases from Anabaena sp. Pasteur Culture Collection 7120 and N. punctiforme American Type Culture Collection 29133 with the cellulose synthases of other prokaryotes, Arabidopsis, Gossypium hirsutum, Populus alba × Populus tremula, corn (Zea mays), and Dictyostelium discoideumshowed that cyanobacteria share an insertion between conserved regions U1 and U2 found previously only in eukaryotic sequences. Furthermore, phylogenetic analysis indicates that the cyanobacterial cellulose synthases share a common branch with CesAs of vascular plants in a manner similar to the relationship observed with cyanobacterial and chloroplast 16s rRNAs, implying endosymbiotic transfer of CesA from cyanobacteria to plants and an ancient origin for cellulose synthase in eukaryotes.

The evolutionary development of plant body plans

“…For example, remarkable molecular homologies among the functionally nonredundant cellulose synthase genes (CesA) exist across diverse clades. Ultrastructural comparisons of the trans-membrane complexes containing CesA proteins support this hypothesis (Delmer 1999;Richmond and Somerville 2000;Nobles et al 2001;Roberts et al 2002;Römling 2002). All members of the CesA gene family isolated from embryophytes encode for integral membrane proteins with one or two trans-membrane helices in the N-terminal protein region, three to six trans-membrane helices in the C-terminal region, and an N-terminal domain structure that includes a cytoplasmic loop of four conserved regions (U1-U4), each of which contains a D residue or the QXXRW sequence, which is predicted to code for glycosyltransferase functionality (Richmond and Somerville 2000).…”

“…Molecular comparisons indicate that the CR-P insertion and the D-D-D-QXXRW motif evolved before the appearance of the embryophytes -indeed, before that of eukaryotes -because both features have been identified in CesA proteins from the green alga Mesotaenium caldariorum (Roberts et al 2002) and in CesA-like proteins from cyanobacteria (Nobles et al 2001). Thus, the genome for cellulose biosynthesis may be traceable to the endosymbiotic origins of chloroplasts, a key event in the history of life (Niklas 2004).…”

Hormonal regulation in green plant lineage families

“…As pointed out by Bode and Müller (2003), in contrast to the generally accepted hypothesis, several plant-specific metabolic pathways have in recent years also been found in prokaryotes. For instance cellulase synthase in vascular plants has been suggested to been transferred from cyanobacteria to plants (Nobles et al, 2001). …”

Cellulose and Its Derivatives Use in the Pharmaceutical Compounding Practice

“…It is present in the cell walls of a great diversity of organisms, from bacteria (Cyanobacteria), prokaryotes (Acetobacter, Rhizobium, Agrobacterium) to eukaryotes (fungis, amoebae, green algae, freshwater and marine algae, mosses, ferns, angiosperms, gymnosperms). It is also produced by some animals, the tunicates (urochordates), members of the subphylum Tunicata in the Chordata phylum [17][18][19]. Native cellulose made by biosynthesis in living organisms is composed only of glucose monomers, as anhydroglucose (AGU) or glucan units (C6H10O5, n) with -1,4 linkages ( Figure 1).…”