1 January 2002
Stow the ax: Cellulose may save trees
Austin, TexasCellulose in a special group of organisms could produce itself and eventually eliminate the need to harvest trees for wood or pulp, said researchers at the University of Texas at Austin.
Blue-green algae are among the most ancient of today's living organisms and have been in existence for more than 2.8 billion years. Cellulose is a biopolymer that plants use as the primary building block for their cell walls. Cellulose is important economically because it is the major source of such significant and useful plant products as wood, cotton, and flax.
"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," said David R. Nobles, a third-year graduate student and lead author of a paper published in the October issue of Plant Physiology.
Another researcher, R. Malcolm Brown Jr., who holds the Johnson & Johnson Centennial Chair in Plant Biology in the Section of Molecular Genetics and Microbiology at UT's School of Biological Sciences, said a possibility based on this discovery could be industrial production of cellulose from cyanobacteria: "If industrial production from this source were to be achieved, we might never need to harvest trees again for wood or pulp. In the future, we could possibly use cyanobacterial cellulose."
The discovery of cellulose biosynthesis in nine species of cyanobacteria, or blue-green algae, may also be the source of genetic material used for cellulose biosynthesis in present-day plants, such as trees and cotton.
Brown said cyanobacteria inhabits vast, incredibly diverse environments ranging from freshwater lakes and ponds to hypersaline water to deserts with no rainfall. Cyanobacteria is common in the dry valleys of Antarctica and can live embedded in the surface of rocks. Some cyanobacteria does not require fresh water, nitrate-based fertilizer, or even arable land to grow and flourish.
From the standpoint of the evolutionary history of life, Brown said the discovery "has shown that the cyanobacterial genes for cellulose production are closely related to those genes in land plants. This strongly suggests that the genetic code for the major building blocks for cellulose production of land plants came directly from the cyanobacteria," he said.