Konjac glucomannan

Takigami, Shoji

doi:10.1016/b978-0-12-820104-6.00001-2

Cited by 6 publications

(3 citation statements)

References 29 publications

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“…The product spectrum for konjac glucomannan showed a continuum of oligosaccharides ranging from DP4 to DP14 (Fig. 4 A, lower panel), which one would expect if the ratio of glucose to mannan distribution is random, which is the case [ 33 ]. Konjac glucomannan contains about 5–10% of the acetylated sugars [ 34 ], and the oligosaccharides observed at masses m/z 2189 ([DP13 + Na + acetyl] + ) and 2352 ([DP14 + Na + acetyl] + ), indeed suggest the presence of acetylation.…”

Section: Resultsmentioning

confidence: 99%

Biochemical and structural characterisation of a family GH5 cellulase from endosymbiont of shipworm P. megotara

Junghare

Manavalan

Fredriksen

et al. 2023

Biotechnol Biofuels

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Background Cellulases play a key role in the enzymatic conversion of plant cell-wall polysaccharides into simple and economically relevant sugars. Thus, the discovery of novel cellulases from exotic biological niches is of great interest as they may present properties that are valuable in the biorefining of lignocellulosic biomass. Results We have characterized a glycoside hydrolase 5 (GH5) domain of a bi-catalytic GH5-GH6 multi-domain enzyme from the unusual gill endosymbiont Teredinibacter waterburyi of the wood-digesting shipworm Psiloteredo megotara. The catalytic GH5 domain, was cloned and recombinantly produced with or without a C-terminal family 10 carbohydrate-binding module (CBM). Both variants showed hydrolytic endo-activity on soluble substrates such as β-glucan, carboxymethylcellulose and konjac glucomannan, respectively. However, low activity was observed towards the crystalline form of cellulose. Interestingly, when co-incubated with a cellulose-active LPMO, a clear synergy was observed that boosted the overall hydrolysis of crystalline cellulose. The crystal structure of the GH5 catalytic domain was solved to 1.0 Å resolution and revealed a substrate binding cleft extension containing a putative + 3 subsite, which is uncommon in this enzyme family. The enzyme was active in a wide range of pH, temperatures and showed high tolerance for NaCl. Conclusions This study provides significant knowledge in the discovery of new enzymes from shipworm gill endosymbionts and sheds new light on biochemical and structural characterization of cellulolytic cellulase. Study demonstrated a boost in the hydrolytic activity of cellulase on crystalline cellulose when co-incubated with cellulose-active LPMO. These findings will be relevant for the development of future enzyme cocktails that may be useful for the biotechnological conversion of lignocellulose.

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Section: Resultsmentioning

confidence: 99%

Biochemical and structural characterisation of a family GH5 cellulase from endosymbiont of shipworm P. megotara

Junghare

Manavalan

Fredriksen

et al. 2023

Biotechnol Biofuels

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show abstract

“…The product spectrum for konjac glucomannan showed a continuum of oligosaccharides ranging from DP4 to DP14 (Fig. 4A, lower panel), which one would expect if the ratio of glucose to mannan distribution is random, which is the case [33]. Konjac glucomannan contains about 5-10% of the acetylated sugars [34], and the oligosaccharides observed at masses m/z 2189 ([DP13 + Na + acetyl]+) and 2352 ([DP14 + Na + acetyl]+), indeed suggest the presence of acetylation.…”

Section: The Products Analysis From Enzymatic Hydrolysismentioning

confidence: 91%

Biochemical and structural characterisation of a family GH5 cellulase from endosymbiont of shipworm P. megotara

Junghare

Manavalan

Fredriksen

et al. 2023

Preprint

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Background Cellulases play a key role in enzymatic conversion of plant cell-wall polysaccharides into simple and economically relevant sugars. The discovery of novel cellulases from exotic biological niches is of interest as they may present properties that are valuable in biorefining of lignocellulose. Results We have characterized a glycoside hydrolase 5 (GH5) domain of a bi-catalytic GH5-GH6 multidomain enzyme from the unusual bacterial endosymbiont Teredinibacter waterbury of the wood-digesting shipworm Psiloteredo megotara. The cellulase enzyme, TwCel5, was produced with and without a native C-terminal family 10 carbohydrate-binding module belongs to GH5, subfamily 2. Both variants showed hydrolytic endo-activity on soluble substrates such as, β-glucan, carboxymethylcellulose and konjac glucomannan. However, low activity was observed towards crystalline form of cellulose. Interestingly, when co-incubated with a cellulose active LPMO, a clear synergy was observed that boosted hydrolysis of crystalline cellulose. The crystal structure of the GH5 catalytic domain was solved to 1.0 Å resolution and revealed a substrate binding cleft containing a putative +3 subsite, which is uncommon in this enzyme family. The enzyme TwCel5 was active in a wide range of pH and temperatures and showed high tolerance for NaCl. Conclusions This study provides an important advance on discovery new enzymes from shipworm and shed new light on biochemical and structural characterization of cellulolytic cellulase and showed boost in hydrolytic activity of cellulase on crystalline cellulose when co-incubated with cellulose active LPMO. These findings will be relevant for the development of future enzyme cocktail that may be useful for the biotechnological conversion of lignocellulose.

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“…KGM absorbs water, swells, and turns into a gel. The swelling property can be accelerated by addition into diluents, heat treatment, or through vigorous stirring 9,15 …”

Section: Water Solubility and Absorption Propertiesmentioning

confidence: 99%

Konjac glucomannan: A functional biopolymer for multifaceted drug delivery applications

Kulkarni,

Agnihotri,

Bhinge

et al. 2024

Polymers for Advanced Techs

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Konjac glucomannan (KGM) is a hydrophilic, neutral polysaccharide obtained from the corm of Amorphophallus konjac (Araceae). Excellent biodegradability, biocompatibility, and nontoxicity has marked the utilization of KGM in variety of drug delivery and biomedical applications. KGM has generally regarded as safe (GRAS) status approved by the United States Food and Drug Administration. The gelling, and film‐forming properties possessed by native KGM has attracted a widespread attention of the researchers for exploring its drug delivery potential. Additionally, the versatility of KGM modifications further extends the drug delivery opportunities through ever‐increasing array of functional properties of KGM. Present review is aimed at presenting the state‐of‐the‐art collection of structure, functional properties, biosynthesis, in vitro and in vivo degradation, chemical modifications, and finally, the drug delivery applications of the KGM. Authors tried to cover the aspects of the KGM relevant to the formulation personnel, and academicians involved in the investigation on variety of pharmaceutical, biotechnological, and biomedical applications of KGM. This article may encourage the investigators to explore the use of KGM, owing to its beneficial traits, as pharmaceutical excipient for drug delivery applications.

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Konjac glucomannan

Cited by 6 publications

References 29 publications

Biochemical and structural characterisation of a family GH5 cellulase from endosymbiont of shipworm P. megotara

Biochemical and structural characterisation of a family GH5 cellulase from endosymbiont of shipworm P. megotara

Biochemical and structural characterisation of a family GH5 cellulase from endosymbiont of shipworm P. megotara

Konjac glucomannan: A functional biopolymer for multifaceted drug delivery applications

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