The initial kinetics of hydrolysis by cellobiohydrolases I and II is consistent with a cellulose surface − erosion model

Väljamaë, Priit; Sild, Veljo; Pettersson, Göran; Johansson, Gunnar

doi:10.1046/j.1432-1327.1998.2530469.x

Cited by 136 publications

(137 citation statements)

References 5 publications

Supporting

Mentioning

122

Contrasting

Unclassified

Order By: Relevance

“…Among such phenomena are effects of high enzyme loading, including competitive or synergistic adsorption of cellulase components (Jeoh et al, 2002;Kyriacou et al, 1989;Ryu et al, 1984), as well as implications of incorporating a substrate material balance distinguishing between free and total substrate sites (Lynd et al, 2002). Further phenomena relevant in this context include changes in F a and perhaps other substrate properties during the course of hydrolysis (Ooshima et al, 1990;Valjamae et al, 1998;Zhang et al, 1999), as well as product inhibition (Gong et al, 1977;Holtzapple et al, 1990;Hong et al, 1981;Ladisch et al, 1980Ladisch et al, , 1981, substrate inhibition (Fenske et al, 1999;Hong et al, 1981;Huang and Penner, 1991;Valjamae et al, 2001), and cellulase deactivation and/or unproductive binding (Kadam et al, 2004;Valjamae et al, 2001). A model that meaningfully incorporates random adsorption, active-and inactive-adsorbed species, and dependence upon the availability of chain ends is an important objective for future research.…”

Section: Discussionmentioning

confidence: 99%

A functionally based model for hydrolysis of cellulose by fungal cellulase

Zhang

Lynd

2006

Biotechnol. Bioeng.

204

158

View full text Add to dashboard Cite

A new functionally based kinetic model for enzymatic hydrolysis of pure cellulose by the Trichoderma cellulase system is presented. The model represents the actions of cellobiohydrolases I, cellobiohydrolase II, and endoglucanase I; and incorporates two measurable and physically interpretable substrate parameters: the degree of polymerization (DP) and the fraction of b-glucosidic bonds accessible to cellulase, F a (Zhang and Lynd, 2004). Initial enzyme-limited reaction rates simulated by the model are consistent with several important behaviors reported in the literature, including the effects of substrate characteristics on exoglucanase and endoglucanase activities; the degree of endo/exoglucanase synergy; the endoglucanase partition coefficient on hydrolysis rates; and enzyme loading on relative reaction rates for different substrates. This is the first cellulase kinetic model involving a single set of kinetic parameters that is successfully applied to a variety of cellulosic substrates, and the first that describes more than one behavior associated with enzymatic hydrolysis. The model has potential utility for data accommodation and design of industrial processes, structuring, testing, and extending understanding of cellulase enzyme systems when experimental date are available, and providing guidance for functional design of cellulase systems at a molecular scale. Opportunities to further refine cellulase kinetic models are discussed, including parameters that would benefit from further study.

show abstract

Section: Discussionmentioning

confidence: 99%

A functionally based model for hydrolysis of cellulose by fungal cellulase

Zhang

Lynd

2006

Biotechnol. Bioeng.

204

158

View full text Add to dashboard Cite

show abstract

“…On the other hand, an increase of enzyme concentration produces a higher density of cellulase on the crystalline surface, and these bound molecules may interfere with the ability of the CD of other enzyme molecules to capture a single cellulose chain. Since CBH is adsorbed on the surface of the substrate only via CBD, but not via both CD and CBD, this is called non-productive binding, because no hydrolytic product is formed by these molecules (14). Therefore, there is an optimum amount of adsorbed enzyme on the surface of cellulose.…”

Section: B Hydrolysis Of Crystalline Cellulose By Cellobiohydrolasementioning

confidence: 99%

Kinetic Analysis of Cellobiohydrolase: Quantification of Enzymatic Reaction at a Solid/Liquid Interface Applying the Concept of Surface Density

Igarashi

Wada

Samejima

2009

TIGG

View full text Add to dashboard Cite

In nature, crystalline cellulose is mainly degraded by cellobiohydrolases (CBHs) produced by various microorganisms. Since both substrate and enzymatic features relate to the reaction and the reaction proceeds at a solid/liquid interface, it is quite di‹cult to perform the quantitative analysis of CBH. In the present study, we estimate the surface area of crystalline celluloses by the adsorption maxima (Amax) of CBH, the speciˆc activity of CBH (k＝v/A) was plotted versus surface density ( r＝ A/Amax) to adjust for the diŠerence of surface area, and quantify the reaction rate of CBH. The results obtained from the approach indicate that the feature of crystalline cellulose greatly aŠects the reaction of CBH.

show abstract

“…Primarily due to the limitations of the assay methods that have been employed, most of the previous enzymecellulosic substrate interaction studies have used purified enzymes or reconstituted mixtures of purified enzymes [15,16] and/ or model substrates such as pure cellulose or substrates with a very low lignin content [17,18] to simplify the subsequent enzyme assays and analyses. While these studies have advanced our understanding of enzymes-substrate interaction, they have not looked at the interactions occurring during the hydrolysis of an industrially relevant lignocellulosic substrate using a complete enzyme mixture.…”

Section: Introductionmentioning

confidence: 99%

The Development and Use of an Elisa-Based Method to Follow the Distribution of Cellulase Monocomponents During the Hydrolysis of Pretreated Corn Stover

Pribowo¹,

Hu²,

Arantes³

et al. 2015

Fuel Production From Non-Food Biomass

View full text Add to dashboard Cite

Background: It is widely recognised that fast, effective hydrolysis of pretreated lignocellulosic substrates requires the synergistic action of multiple types of hydrolytic and some non-hydrolytic proteins. However, due to the complexity of the enzyme mixture, the enzymes interaction with and interference from the substrate and a lack of specific methods to follow the distribution of individual enzymes during hydrolysis, most of enzyme-substrate interaction studies have used purified enzymes and pure cellulose model substrates. As the enzymes present in a typical "cellulase mixture" need to work cooperatively to achieve effective hydrolysis, the action of one enzyme is likely to influence the behaviour of others. The action of the enzymes will be further influenced by the nature of the lignocellulosic substrate. Therefore, it would be beneficial if a method could be developed that allowed us to follow some of the individual enzymes present in a cellulase mixture during hydrolysis of more commercially realistic biomass substrates. Results: A high throughput immunoassay that could quantitatively and specifically follow individual cellulase enzymes during hydrolysis was developed. Using monoclonal and polyclonal antibodies (MAb and PAb, respectively), a double-antibody sandwich enzyme-linked immunosorbent assay (ELISA) was developed to specifically quantify cellulase enzymes from Trichoderma reesei: cellobiohydrolase I (Cel7A), cellobiohydrolase II (Cel6A), and endoglucanase I (Cel7B). The interference from substrate materials present in lignocellulosic supernatants could be minimized by dilution. Conclusion: A double-antibody sandwich ELISA was able to detect and quantify individual enzymes when present in cellulase mixtures. The assay was sensitive over a range of relatively low enzyme concentration (0 -1 μg/ml), provided the enzymes were first pH adjusted and heat treated to increase their antigenicity. The immunoassay was employed to quantitatively monitor the adsorption of cellulase monocomponents, Cel7A, Cel6A, and Cel7B, that were present in both Celluclast and Accellerase 1000, during the hydrolysis of steam-pretreated corn stover (SPCS). All three enzymes exhibited different individual adsorption profiles. The specific and quantitative adsorption profiles observed with the ELISA method were in agreement with earlier work where more labour intensive enzyme assay techniques were used.

show abstract

The initial kinetics of hydrolysis by cellobiohydrolases I and II is consistent with a cellulose surface − erosion model

Cited by 136 publications

References 5 publications

A functionally based model for hydrolysis of cellulose by fungal cellulase

A functionally based model for hydrolysis of cellulose by fungal cellulase

Kinetic Analysis of Cellobiohydrolase: Quantification of Enzymatic Reaction at a Solid/Liquid Interface Applying the Concept of Surface Density

The Development and Use of an Elisa-Based Method to Follow the Distribution of Cellulase Monocomponents During the Hydrolysis of Pretreated Corn Stover

Contact Info

Product

Resources

About