Aerobic Microbial Cellulase Systems

Wilson, David B.

doi:10.1002/9781444305418.ch11

Cited by 21 publications

(18 citation statements)

References 96 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Many aerobic microorganisms use the free cellulase mechanism involving the secretion of a set of individual cellulases, which then act synergistically to degrade cellulose [14]. Cellulase synergism can increase the specific activity of appropriate mixtures by up to 15-fold compared to individual cellulases [15].…”

Section: Microbial Sources Of Cellulasementioning

confidence: 99%

Cellulases from Insects

Fischer

Ostafe

Twyman

2013

Yellow Biotechnology II

View full text Add to dashboard Cite

Bioethanol is currently produced by the fermentation of sugary and starchy crops, but waste plant biomass is a more abundant source because sugars can be derived directly from cellulose. One of the limiting steps in the biomass-to-ethanol process is the degradation of cellulose to fermentable sugars (saccharification). This currently relies on the use of bacterial and/or fungal cellulases, which tend to have low activity under biorefinery conditions and are easily inhibited. Some insect species feed on plant biomass and can efficiently degrade cellulose to produce glucose as an energy source. Although insects were initially thought to require symbiotic relationships with bacteria and fungi to break down cellulose, several species in the orders Dictyoptera, Orthoptera, and Coleoptera have now been shown to produce their own cellulases in the midgut or salivary glands, and putative cellulase genes have been identified in other orders. Insect cellulases often work in concert with cellulases provided by symbiotic microbiota in the gut to achieve efficient cellulolysis. We discuss the current status of insect cellulases and potential strategies that could be used to find novel enzymes and improve their efficiency.

show abstract

Section: Microbial Sources Of Cellulasementioning

confidence: 99%

Cellulases from Insects

Fischer

Ostafe

Twyman

2013

Yellow Biotechnology II

View full text Add to dashboard Cite

show abstract

“…Thus, there is great incentive to utilize cellulosic biomass via its breakdown to soluble sugars that can then be fermented to ethanol. In nature, the decomposition of lignocellulose is mediated by microorganisms, representing a key step in the carbon cycle on Earth (4,19,36,37). The hydrolysis of cellulose is very challenging, since it has a highly ordered, tightly packed crystalline structure; in addition, the polymer is associated with hemicellulose and surrounded by a lignin seal (16).…”

mentioning

confidence: 99%

Cellodextrin and Laminaribiose ABC Transporters in Clostridium thermocellum

et al. 2009

View full text Add to dashboard Cite

Clostridium thermocellum is an anaerobic thermophilic bacterium that grows efficiently on cellulosic biomass. This bacterium produces and secretes a highly active multienzyme complex, the cellulosome, that mediates the cell attachment to and hydrolysis of the crystalline cellulosic substrate. C. thermocellum can efficiently utilize only ␤-1,3 and ␤-1,4 glucans and prefers long cellodextrins. Since the bacterium can also produce ethanol, it is considered an attractive candidate for a consolidated fermentation process in which cellulose hydrolysis and ethanol fermentation occur in a single process. In this study, we have identified and characterized five sugar ABC transporter systems in C. thermocellum.

show abstract

“…The most reviewed is the fungi, Trichoderma reesei, which has been used industrially for production and extraction of cellulases (Wilson 2008). Nevertheless, anaerobic bacteria such as Clostridium spp and fungi including, genera Neocallimastix, Piromonas, and Sphaeromonas comprise complexed cellulase systems, where the cellulose hydrolyzing enzymes are enclosed in membranebound enzyme complexes (called cellulosomes).…”

Section: Microbial Degradation Of Cellulose and Hemicellulosementioning

confidence: 99%

Biogas from Lignocellulosic Materials

Kabir

Forgács

Horváth

2015

Lignocellulose-Based Bioproducts

View full text Add to dashboard Cite

Methane production via anaerobic digestion is a steadily growing industry in Europe and all over the world. Biomethane reduces the demand for fossil fuels, since it can be used for the production of power and heat or converted to vehicle fuel. Anaerobic digestion is a renewable energy technology; however, it can also be considered as a low-cost environmental-friendly waste management process, since it reduces the emission of greenhouse gases (GHGs), while it stabilizes the wastes. Currently, mainly the organic fraction of household waste, food waste, sewage sludge, manure, and energy crops is used for biogas production; nevertheless, there are a wide range of other organic substrates which can be utilized for biogas production. Among the organic matters, lignocellulosic materials have a great potential. Great abundance worldwide and carbohydrate-rich contents make them an attractive feedstock for biofuel production. Currently, anaerobic digestion of energy crops is widespread; however, biogas production from lignocellulosic residuals and wastes is still under investigation. This chapter focuses on anaerobic digestion of lignocellulosic materials. It explains the anaerobic digestion process and the current technologies used for crops digestion. It also summarizes the biogas potential of different lignocellulosic materials and the latest research on pretreatments to improve the methane yield. Finally, this chapter compares anaerobic digestion of lignocellulosic materials with energy production from these kinds of materials through thermochemical processes.

show abstract

Aerobic Microbial Cellulase Systems

Cited by 21 publications

References 96 publications

Cellulases from Insects

Cellulases from Insects

Cellodextrin and Laminaribiose ABC Transporters in Clostridium thermocellum

Biogas from Lignocellulosic Materials

Contact Info

Product

Resources

About