Cellulose-degrading bacteria

Cows and termites can break down cellulose because they harbor cellulose-degrading bacteria in their gut. 

Fig. 4 Cellulose-degrading bacteria on cellulose fibers (phase contrast microscopy, x 1,000 magnification)...

Identification of key players for cellulose degradation in the biogas fermenter is hampered by the limited knowledge on truly cellulolytic bacteria. Some important cellulose-degrading bacteria in nature seem to be still undetected,... 

Elberson MA, Malekzadeh F, Yazdi MT, Kameranpour N, Noori-Dloii MR, Matte MH, Shahamat M, Colwell RR, Sowers KR (2000) Cellulomonaspersica sp. nov. and Cellulomonas iranensis sp. nov., mesophilic cellulose-degrading bacteria isolated from forest soil. Int J Syst Evol Microbiol 50 993-996... 

Under natural conditions, cotton products are widely used in contact with the soil (fabrics for tents) receiving damage both from the inside and the outside. The main role here is played by cellulose degrading bacteria and fungi. 

RunUnococcus albus and Ruminococcus flavefadens. These bacteria are important cellulose-degraders found in the rumen of cattle and sheep (2). Most isolated strains ferment cellulose and xylan and all ferment cellobiose. Fermentation of glucose and some other carbohydrates depends on the particular strain. R flavefadens and B. succinogenes can ferment the highly ordered crystalline cellulosic su trates but R albus cannot. No evidence has been found for extracellular cellulase production by R albus, but Ohmiya et al. purified cellobiosidase from this culture 17). Laboratory growth of R albus has been conducted at pH 7.0 and 37 C. 

Weimer, P.J. and Odt, C.L., Cellulose degradation by ruminal microbes physiological and hydrolytic diversity among ruminal cellulolytic bacteria, in Enzymatic Degradation of Insoluble Carbohydrates, Saddler, J.N. and Penner, M.H., Eds., ACS Symposium Series, No. 618, American Chemical Society, Washington, D.C., 1995, chap. 18. 

Schwarz W. H. (2001) The cellulosome and cellulose degradation by anaerobic bacteria. Appl. Microbiol. Bio-technol. 56(5-6), 634-649. 

Schwarz WH. (2001). The ceUulosome and cellulose degradation hy anaerobic bacteria. Appl Microbiol Biotechnol, 56, 634-649. 

The final areas in which PHB biodegradation is of interest are the specialized cellulose-degrading locations of animals, such as the rumen of cattle and sheep and the colons of goats. PHB is degraded in these environments and, as one would expect, the rate is intermediate between slow hydrolysis in vivo and the more rapid attack of bacteria and fungi in soil or sewage. 

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