A newly described cellulosomal cellobiohydrolase, CelO, from Clostridium thermocellum: investigation of the exo-mode of hydrolysis, and binding capacity to crystalline cellulose
               The GenBank accession number for the sequence determined in this work is AJ275975.

Zverlov, Vladimir V.; Velikodvorskaya, G. A.; Schwarz, Wolfgang H.

doi:10.1099/00221287-148-1-247

Cited by 52 publications

(40 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…3), as is typical for cellobiohydrolases, including those acting on crystalline cellulose [4,11]. However, analysis of the kinetics of ASC digestion with Cel48C showed the additional production of minor amounts of cellotriose and cellotetraose (not shown), suggesting that the enzyme could bear some minor endoglucanase activity, as described for certain exocellulases [10].…”

Section: Mode Of Action Of Cel48cmentioning

confidence: 99%

“…Reducing-end directed processive exocellulases have already been described among family 48 glycosyl hydrolases [8,9], with some members also having some endoglucanase activity like Cel48C [10,11]. Nevertheless, the real function of such class of enzymes has not been solved to date, as they show very low and restricted activity on most common cellulosic substrates.…”

Section: Mode Of Action Of Cel48cmentioning

confidence: 99%

“…The results obtained indicate that, although very low, the enzyme bears activity on these substrates and suggest that Cel48C cannot proceed from the free nonreducing end of the sugar chain. In fact, if pNP-cellopentaoside were hydrolysed from the nonreducing end, the expected products would be cellobiose and pNP-glucoside (or pNP-cellotrioside) [10], not found after Cel48C hydrolysis. Although it cannot be ruled out that the presence of the aromatic group may affect the expected pattern of degradation, cellobiose should be released after hydrolysis from the nonreducing end [9].…”

Section: Mode Of Action Of Cel48cmentioning

confidence: 99%

“…Thus, cellulose can only access the active site through one of its ends, where the enzyme acts processively releasing cellobiose units by sliding along the substrate chain [4,8]. Although the activity of most cellobiohydrolases occurs at the nonreducing end of the glucose polymer, certain processing enzymes acting from the reducing end of the carbohydrate chain have been identified [9,10,11]. Existence of both types of processive enzymes with specificity for either chain-end would account for a productive and complete degradation of cellulose [9,12].…”

mentioning

confidence: 99%

See 3 more Smart Citations

Exo‐mode of action of cellobiohydrolase Cel48C from Paenibacillus sp. BP‐23

Sánchez

Pastor

Dı́az

2003

European Journal of Biochemistry

View full text Add to dashboard Cite

Sequence analysis of a Paenibacillus sp. BP-23 recombinant clone coding for a previously described endoglucanase revealed the presence of an additional truncated ORF with homology to family 48 glycosyl hydrolases. The corresponding 3509-bp DNA fragment was isolated after gene walking and cloned in Escherichia coli Xl1-Blue for expression and purification. The encoded enzyme, a cellulase of 1091 amino acids with a deduced molecular mass of 118 kDa and a pI of 4.85, displayed a multidomain organization bearing a canonical family 48 catalytic domain, a bacterial type 3a cellulose-binding module, and a putative fibronectin-III domain. The cloned cellulase, unique among Bacillales and designated Cel48C, was purified through affinity chromatography using its ability to bind Avicel. Maximum activity was achieved at 45°C and pH 6.0 on acid-swollen cellulose, bacterial microcrystalline cellulose, Avicel and cellodextrins, whereas no activity was found on carboxy methyl cellulose, cellobiose, cellotriose, pNPglycosides or 4-methylumbeliferyl a-D-glucoside. Cellobiose was the major product of cellulose hydrolysis, identifying Cel48C as a processive cellobiohydrolase. Although no chromogenic activity was detected from pNP-glycosides, TLC analysis revealed the release of p-nitrophenyl-glycosides and cellodextrins from these substrates, suggesting that Cel48C acts from the reducing ends of the sugar chain. Presence of such a cellobiohydrolase in Paenibacillus sp. BP-23 would contribute to widen up its range of action on natural cellulosic substrates.

show abstract

Section: Mode Of Action Of Cel48cmentioning

confidence: 99%

Section: Mode Of Action Of Cel48cmentioning

confidence: 99%

Section: Mode Of Action Of Cel48cmentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Exo‐mode of action of cellobiohydrolase Cel48C from Paenibacillus sp. BP‐23

Sánchez

Pastor

Dı́az

2003

European Journal of Biochemistry

View full text Add to dashboard Cite

show abstract

“…C. thermocellum produces a multiprotein complex, the cellulosome, which contains a range of cellulases, hemicellulases, structural components, and carbohydrate binding domains (7). In aerobic conditions white rot fungi, such as Phanaerochaete chyrosporium (8), or brown rot fungi such as Postia placenta (9), are major degraders of woody biomass.…”

mentioning

confidence: 99%

Molecular insight into lignocellulose digestion by a marine isopod in the absence of gut microbes

King

Cragg

et al. 2010

Proc. Natl. Acad. Sci. U.S.A.

118

105

View full text Add to dashboard Cite

The digestion of lignocellulose is attracting attention both in terms of basic research into its metabolism by microorganisms and animals, and also as a means of converting plant biomass into biofuels. Limnoriid wood borers are unusual because, unlike other wood-feeding animals, they do not rely on symbiotic microbes to help digest lignocellulose. The absence of microbes in the digestive tract suggests that limnoriid wood borers produce all the enzymes necessary for lignocellulose digestion themselves. In this study we report that analysis of ESTs from the digestive system of Limnoria quadripunctata reveals a transcriptome dominated by glycosyl hydrolase genes. Indeed, >20% of all ESTs represent genes encoding putative cellulases, including glycosyl hydrolase family 7 (GH7) cellobiohydrolases. These have not previously been reported in animal genomes, but are key digestive enzymes produced by wood-degrading fungi and symbiotic protists in termite guts. We propose that limnoriid GH7 genes are important for the efficient digestion of lignocellulose in the absence of gut microbes. Hemocyanin transcripts were highly abundant in the hepatopancreas transcriptome. Based on recent studies indicating that these proteins may function as phenoloxidases in isopods, we discuss a possible role for hemocyanins in lignin decomposition. biofuels | cellulase | hemocyanin | phenoloxidase | wood degradation

show abstract