Chapter 5 - Microbial Diversity and Cellulase Production

Abstract

Even though only a small fraction of bacterial species can grow on cellulose as a sole carbon source, there is extensive diversity among cellulolytic bacteria for aerobic and anaerobic species. Out of 29 cultured bacterial phyla, 6 contain cellulolytic species. About half of the known cellulolytic bacteria are saprophytes that degrade dead plant material either in the soil, in the rumen, or in termites. Some soil saprophytes are aerobic and some are anaerobic. Many of the other cellulolytic bacteria are plant pathogens, which can degrade living plants. Many fungi degrade cellulose with most being aerobes, but a few anaerobic fungi degrade cellulose and they are found in the rumen. At this time there are only two reported cellulolytic archaea: Desulfurococcus fermentans and Thermogladius cellulolyticus, although there are other archaea that contain cellulase genes.