Furthermore, changes in protein levels in response to growth phas

Furthermore, changes in protein levels in response to growth phase may help in hypothesizing

regulatory elements that may be targeted for increasing product yields during monoculture and co-culture fermentation processes. Below we discuss key proteins involved in carbohydrate utilization and transport, glycolysis, energy storage, pentose phosphate production, pyruvate catabolism, end-product synthesis, and energy production. Proteins involved in STAT inhibitor cellulose and (hemi)cellulose degradation and transport Cellulose hydrolysis C. thermocellum encodes a number of carbohydrate active enzymes (CAZymes) allowing for efficient degradation of cellulose and associated polysaccharides

(Carbohydrate Active Enzyme database; http://​www.​cazy.​org/​). Torin 1 These include (i) endo-β-glucanases, which cleave internal amorphous regions of the cellulose chain into shorter soluble oligosaccharides, (ii) exo-β-glucanases (cellodextrinases and cellobiohydrolases), which act in a possessive manner on reducing or nonreducing ends of the cellulose chain liberating shorter cellodextrins, and (iii) β-glucosidases (cellodextrin and MEK162 ic50 cellobiose phosphorylases), which hydrolyze soluble cellodextrins ultimately O-methylated flavonoid into glucose [10]. Other glycosidases that allow hydrolysis of lignocellulose include xylanases, lichenases, laminarinases, β-xylosidases, β-galactosidases, and β-mannosidases, while pectin processing

is accomplished via pectin lyase, polygalacturonate hydrolase, and pectin methylesterase [64, 65]. These glycosidases may be secreted as free enzymes or may be assembled together into large, cell-surface anchored protein complexes (“cellulosomes”) allowing for the synergistic breakdown of cellulosic material. The cellulosome consists of a scaffoldin protein (CipA) which contains (i) a cellulose binding motifs (CBM) allowing for the binding of the scaffoldin to the cellulose fiber, (ii) nine type I cohesion domains with that mediate binding of various glycosyl hydrolases via their type I dockerin domains, and (iii) a type II dockerin domain which mediates binding to the type II cohesion domain found on the cell-surface anchoring proteins. The cell-surface anchoring proteins are in turn noncovalently bound to the peptidoglycan cell wall via C-terminal surface-layer homology (SLH) repeats [64]. During growth on cellulose, the cellulosome is attached to the cell in early exponential phase, released during late exponential phase, and is found attached to cellulose during stationary phase [64].

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