scholarly journals Conditions of hydrolysis with a specific pair of endo- and exo-cellulases

2021 ◽  
Author(s):  
Yoshiki Kitano
Keyword(s):  
Synergistic Effect ◽  
Crystalline Cellulose ◽  
Carbohydrate Binding ◽  
Amorphous Cellulose ◽  
Potential Synergy ◽  
Hydrolysis Of Cellulose ◽  
Potential Alternative ◽  
Specific Pair ◽  
Hydrolysis Of ◽  
Increased Activity

Enzymatic hydrolysis of cellulose is a technology involved in the production of bioethanol, a potential alternative renewable energy. Many cellulases with endo- and exo- type of activity are known to hydrolyze cellulose synergistically. In this thesis, potential synergy between an endo-cellulase, Cel5B, with and without a carbohydrate- binding module (CBM6), and a new exo-cellulase, CBH1, from Trichoderma harzianum FP108 were examined during the hydrolysis of semi- crystalline cellulose (Avicel). Since CBM6 is recognized as having a high affinity for amorphous cellulose, it was hypothesized that this affinity could enhance the synergistic effect between the endo- and exo-cellulases by focusing the action to Cel5B+CBM6 on the amorphous regions of the Avicel substrate. The increased activity of Cel5B+CBM6 over Cel5B alone was confirmed. However, in contrast to our expectations, a synergistic effect was not observed between either endo- and exo-cellulase pairs. From the obtained hydrolysis yield, it was inferred that Cel5B+CBM6 may have exo-type activity that caused a competitive interaction with the exo-cellulase, which resulted in no synergy.

scholarly journals Conditions of hydrolysis with a specific pair of endo- and exo-cellulases

2021 ◽  
Author(s):  
Yoshiki Kitano
Keyword(s):  
Synergistic Effect ◽  
Crystalline Cellulose ◽  
Carbohydrate Binding ◽  
Amorphous Cellulose ◽  
Potential Synergy ◽  
Hydrolysis Of Cellulose ◽  
Potential Alternative ◽  
Specific Pair ◽  
Hydrolysis Of ◽  
Increased Activity

Enzymatic hydrolysis of cellulose is a technology involved in the production of bioethanol, a potential alternative renewable energy. Many cellulases with endo- and exo- type of activity are known to hydrolyze cellulose synergistically. In this thesis, potential synergy between an endo-cellulase, Cel5B, with and without a carbohydrate- binding module (CBM6), and a new exo-cellulase, CBH1, from Trichoderma harzianum FP108 were examined during the hydrolysis of semi- crystalline cellulose (Avicel). Since CBM6 is recognized as having a high affinity for amorphous cellulose, it was hypothesized that this affinity could enhance the synergistic effect between the endo- and exo-cellulases by focusing the action to Cel5B+CBM6 on the amorphous regions of the Avicel substrate. The increased activity of Cel5B+CBM6 over Cel5B alone was confirmed. However, in contrast to our expectations, a synergistic effect was not observed between either endo- and exo-cellulase pairs. From the obtained hydrolysis yield, it was inferred that Cel5B+CBM6 may have exo-type activity that caused a competitive interaction with the exo-cellulase, which resulted in no synergy.

scholarly journals In situ detection of cell wall polysaccharides in sitka spruce (Picea sitchensis (Bong.) Carrière) wood tissue

BioResources ◽  
2007 ◽  
Vol 2 (2) ◽  
pp. 284-295
Author(s):  
Clemens Altaner ◽  
J. Paul Knox ◽  
Michael C. Jarvis
Keyword(s):  
Cell Wall ◽  
Monoclonal Antibodies ◽  
Cell Walls ◽  
Sitka Spruce ◽  
Picea Sitchensis ◽  
Crystalline Cellulose ◽  
Carbohydrate Binding ◽  
Cell Wall Polysaccharides ◽  
Amorphous Cellulose ◽  
Carbohydrate Binding Modules

Wood cell wall polysaccharides can be probed with monoclonal antibodies and carbohydrate-binding modules (CBMs). Binding of monoclonal antibodies to β-1-4-xylan, β-1-4-mannan, β-1-3-glucan, and α-1-5-arabinan structures were observed in native Sitka spruce (Picea sitchensis (Bong.) Carrière) wood cell walls. Furthermore CBMs of different families, differing in their affinities for crystalline cellulose (3a) and amorphous cellulose (17 and 28), were shown to bind to the native wood cell walls with varying intensities. Resin channel forming cells exhibited an increased β-1-4-xylan and a decreased β-1-4-mannan content. Focusing on severe compression wood (CW) tracheids, β-1-3-glucan was found towards the cell lumen. In contrast, α-1-5-arabinan structures were present in the intercellular spaces between the round tracheids in severe CW, highlighting the importance of this polymer in cell adhesion.

scholarly journals Surface Pitting on Nanofibrous Matrix as an Ultra- Sensitive Indicator for Enzymatic Hydrolysis of Crystalline Cellulose

2021 ◽  
Author(s):  
mikiko tsudome ◽  
Mikako Tachioka ◽  
Miwako Tsuda ◽  
Yoshihiro Takaki ◽  
Shigeru Deguchi
Keyword(s):  
Enzymatic Hydrolysis ◽  
Enzymatic Degradation ◽  
Synthetic Polymers ◽  
Water Soluble ◽  
Crystalline Cellulose ◽  
Optical Profilometry ◽  
Enzymatic Hydrolysis Of Cellulose ◽  
Reaction Proceeds ◽  
Hydrolysis Of Cellulose ◽  
Hydrolysis Of

<p>Assaying enzymatic degradation of the water-insoluble substrate such as cellulose and synthetic polymers has remained technically challenging, primarily because only the surface of the substrate is accessible to the enzymes and the reaction proceeds very slowly compared with those of water-soluble substrates. Here we show an ultra-sensitive and semi-quantitative assay for enzymatic hydrolysis of cellulose. By combining nanofibrous matrices with piezo-driven inkjet printing and optical profilometry, enzymatic hydrolysis of less than 1 nanogram of crystalline cellulose was successfully quantified. Unprecedented genetic diversity of cellulase was revealed when the same principle was applied for elucidating microbial degradation of cellulose in the deep sea. This work demonstrates that truly interdisciplinary efforts, encompassing diverse disciplines from nanotechnology to microbiology, are crucial to address scientific and technological problems towards sustainability.<br></p>

scholarly journals The Fibronectin Type 3-Like Repeat from the Clostridium thermocellum Cellobiohydrolase CbhA Promotes Hydrolysis of Cellulose by Modifying Its Surface

2002 ◽  
Vol 68 (9) ◽  
pp. 4292-4300 ◽  
Author(s):  
Irina A. Kataeva ◽  
Ronald D. Seidel ◽  
Ashit Shah ◽  
Larry T. West ◽  
Xin-Liang Li ◽  
...  
Keyword(s):  
Filter Paper ◽  
Clostridium Thermocellum ◽  
Catalytic Domain ◽  
Glycosyl Hydrolase ◽  
Binding Domain ◽  
Carbohydrate Binding ◽  
Hydrolysis Of Cellulose ◽  
Type 3 ◽  
Hydrolysis Of ◽  
Fibronectin Type

ABSTRACT Fibronectin type 3 homology domains (Fn3) as found in the cellobiohydrolase CbhA of Clostridium thermocellum are common among bacterial extracellular glycohydrolases. The function of these domains is not clear. CbhA is modular and composed of an N-terminal family IV carbohydrate-binding domain (CBDIV), an immunoglobulin-like domain, a family 9 glycosyl hydrolase catalytic domain (Gh9), two Fn3-like domains (Fn31,2), a family III carbohydrate-binding domain (CBDIII), and a dockerin domain. Efficiency of cellulose hydrolysis by truncated forms of CbhA increased in the following order: Gh9 (lowest efficiency), Gh9-Fn31,2 (more efficient), and Gh9-Fn31,2-CBDIII (greatest efficiency). Thermostability of the above constructs decreased in the following order: Gh9 (most stable), Gh9-Fn31,2, and then Gh9-Fn31,2-CBDIII (least stable). Mixing of Orpinomyces endoglucanase CelE with Fn31,2, or Fn31,2-CBDIII increased efficiency of hydrolysis of acid-swollen cellulose (ASC) and filter paper. Scanning electron microscopic studies of filter paper treated with Fn31,2, Fn31,2-CBDIII, or CBDIII showed that the surface of the cellulose fibers had been loosened up and crenellated by Fn31,2 and Fn31,2-CBDIII and to a lesser extent by CBDIII. X-ray diffraction analysis did not reveal changes in the crystallinity of the filter paper. CBDIII bound to ASC and filter paper with capacities of 2.45 and 0.73 μmoles g−1 and relative affinities (K r) of 1.12 and 2.13 liters g−1, respectively. Fn31,2 bound weakly to both celluloses. Fn31,2-CBD bound to ASC and filter paper with capacities of 3.22 and 0.81 μmoles g−1 and K rs of 1.14 and 1.98 liters g−1, respectively. Fn31,2 and CBDIII contained 2 and 1 mol of calcium per mol, respectively. The results suggest that Fn31,2 aids the hydrolysis of cellulose by modifying its surface. This effect is enhanced by the presence of CBDIII, which increases the concentration of Fn31,2 on the cellulose surface.

scholarly journals Increased Crystalline Cellulose Activity via Combinations of Amino Acid Changes in the Family 9 Catalytic Domain and Family 3c Cellulose Binding Module of Thermobifida fusca Cel9A

2010 ◽  
Vol 76 (8) ◽  
pp. 2582-2588 ◽  
Author(s):  
Yongchao Li ◽  
Diana C. Irwin ◽  
David B. Wilson
Keyword(s):  
Amino Acid ◽  
Catalytic Domain ◽  
Crystalline Cellulose ◽  
Thermobifida Fusca ◽  
Carbohydrate Binding ◽  
Synergistic Activity ◽  
The Family ◽  
Cellulose Binding ◽  
Increased Activity ◽  
Catalytic Cleft

ABSTRACT Amino acid modifications of the Thermobifida fusca Cel9A-68 catalytic domain or carbohydrate binding module 3c (CBM3c) were combined to create enzymes with changed amino acids in both domains. Bacterial crystalline cellulose (BC) and swollen cellulose (SWC) assays of the expressed and purified enzymes showed that three combinations resulted in 150% and 200% increased activity, respectively, and also increased synergistic activity with other cellulases. Several other combinations resulted in drastically lowered activity, giving insight into the need for a balance between the binding in the catalytic cleft on either side of the cleavage site, as well as coordination between binding affinity for the catalytic domain and CBM3c. The same combinations of amino acid variants in the whole enzyme, Cel9A-90, did not increase BC or SWC activity but did have higher filter paper (FP) activity at 12% digestion.

scholarly journals CalkGH9T: A Glycoside Hydrolase Family 9 Enzyme from Clostridium alkalicellulosi

Catalysts ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1011
Author(s):  
Paripok Phitsuwan ◽  
Sengthong Lee ◽  
Techly San ◽  
Khanok Ratanakhanokchai
Keyword(s):  
Glycoside Hydrolase ◽  
Cellulose Degradation ◽  
Glycoside Hydrolase Family ◽  
Carbohydrate Binding ◽  
Type I ◽  
Amorphous Cellulose ◽  
Carbohydrate Binding Modules ◽  
Glycoside Hydrolase Family 9 ◽  
Hydrolysis Of ◽  
Hydrolase Family

Glycoside hydrolase family 9 (GH9) endoglucanases are important enzymes for cellulose degradation. However, their activity on cellulose is diverse. Here, we cloned and expressed one GH9 enzyme (CalkGH9T) from Clostridium alkalicellulosi in Escherichia coli. CalkGH9T has a modular structure, containing one GH9 catalytic module, two family 3 carbohydrate binding modules, and one type I dockerin domain. CalkGH9T exhibited maximal activity at pH 7.0–8.0 and 55 °C and was resistant to urea and NaCl. It efficiently hydrolyzed carboxymethyl cellulose (CMC) but poorly degraded regenerated amorphous cellulose (RAC). Despite strongly binding to Avicel, CalkGH9T lacked the ability to hydrolyze this substrate. The hydrolysis of CMC by CalkGH9T produced a series of cello-oligomers, with cellotetraose being preferentially released. Similar proportions of soluble and insoluble reducing ends generated by hydrolysis of RAC indicated non-processive activity. Our study extends our knowledge of the molecular mechanism of cellulose hydrolysis by GH9 family endoglucanases with industrial relevance.

scholarly journals UTILIZATION OF OIL PALM EMPTY FRUIT BUNCH (OPEFB) FOR BIOETHANOL PRODUCTION THROUGH ALKALI AND DILUTE ACID PRETREATMENT AND SIMULTANEOUS SACCHARIFICATION AND FERMENTATION

2010 ◽  
Vol 10 (2) ◽  
pp. 261-267 ◽  
Author(s):  
Yanni Sudiyani ◽  
Euis Hermiati
Keyword(s):  
Oil Palm ◽  
Dilute Acid Pretreatment ◽  
High Price ◽  
Empty Fruit Bunch ◽  
Acid Pretreatment ◽  
Alternative Source ◽  
Hydrolysis Of Cellulose ◽  
Potential Alternative ◽  
The Cost ◽  
Hydrolysis Of

Lignocellulosic biomass is a potential alternative source of bioethanol for energy. The lignocellulosics are abundantly available in Indonesia. Most of them are wastes of agriculture, plantation and forestry. Among those wastes, oil palm empty fruit bunch (OP EFB) is one of a potential lignocellulosics to be converted to bioethanol. This EFB, which is wastes in oil palm factories, is quite abundant (around 25 million tons/year) and also has high content of cellulose (41-47%). The conversion of OPEFB to ethanol basically consists of three steps which are pretreatment, hydrolysis of cellulose and hemicellulose to simple sugars (hexoses and pentoses), and fermentation of simple sugars to ethanol. Acid and alkali pretreatments are considered the simplest methods and are potentially could be applied in the next couple of years. However, there are still some problems that have to be overcome to make the methods economically feasible. The high price of cellulose enzyme that is needed in the hydrolysis step is one of factors that cause the cost of EFB conversion is still high. Thus, the search of potential local microbes that could produce cellulase is crucial. Besides that, it is also important to explore fermenting microbes that could ferment six carbon sugars from cellulose as well as five carbon sugars from hemicellulose, so that the conversion of lignocellulosics, particularly EFB, would be more efficient. Keywords: OPEFB, lignocellulosics, pretreatment, fermentation, ethanol

scholarly journals Cellobiohydrolase from Trichoderma reesei

1983 ◽  
Vol 215 (3) ◽  
pp. 677-683 ◽  
Author(s):  
M Nummi ◽  
M L Niku-Paavola ◽  
A Lappalainen ◽  
T M Enari ◽  
V Raunio
Keyword(s):  
Trichoderma Reesei ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Culture Liquid ◽  
Protein Band ◽  
Immunoaffinity Chromatography ◽  
Amorphous Cellulose ◽  
Single Protein ◽  
Hydrolysis Of Cellulose ◽  
Hydrolysis Of

A 1,4-beta-D-glucan cellobiohydrolase (EC 3.2.1.91) was purified from the culture liquid of Trichoderma reesei by using biospecific sorption on amorphous cellulose and immunoaffinity chromatography. A single protein band in polyacrylamide-gel electrophoresis and one arc in immunoelectrophoresis corresponded to the enzyme activity. The Mr was 65 000. The pI was 4.2-3.6. The purified enzyme contained about 10% hexose. The enzyme differs from previously described cellobiohydrolases in being more effective in the hydrolysis of cellulose.

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