Download or read book Investigating the Enzymatic Hydrolysis of Crystalline Cellulose Using Fluorescence Based Assays written by Navaneetha Santhanam and published by . This book was released on 2009 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The hydrolysis kinetics of bacterial microcrystalline cellulose (BMCC) by the cellulases of Thermobifida fusca was studied using fluorescence based assays in three ways. First, the binding of fluorescence-labeled Cel5A, Cel6B and Cel9A in ternary synergistic mixtures was assessed. A rapid high-throughput binding assay using microwell plates was developed to measure the bound fractions of the three cellulases at varying mole ratios of Cel6B and Cel9A, with Cel5A fixed at 10% of the total cellulase loading. This study revealed that the bound fractions of cellulases in ternary mixtures were additive, unlike the hydrolytic activity which was synergistic. Second, an experimental system was developed for the application of high resolution fluorescence microscopy to examine the binding of individual Cel5A, Cel6B and Cel9A to immobilized cellulose with varying morphologies. The immobilization technique allowed deposition of cellulose morphologies ranging from nanoscale cellulose fibers, to microscale cellulose fibril mats to sub-millimeter scale cellulose particles. Fluorescently labeled Cel5A, Cel6B and Cel9A were successfully integrated with fluorescently labeled cellulose to obtain a miniaturized reaction system which retained the intrinsic binding and hydrolytic capabilities of cellulases. Direct visualization of the binding behavior of individual cellulases on cellulose with different morphologies was achieved using this system which showed that the binding behavior depended strongly on the morphology and complexity of cellulose aggregates. Third, the significance of product inhibition by cellobiose as a rateretarding factor in the hydrolysis of BMCC by Cel9A and Cel9A-68, its construct lacking the family 2 cellulose binding module, was investigated. Fluorescently labeled BMCC was used as the substrate for an analysis of initial rates in the presence of exogenous cellobiose. Increasing cellobiose concentrations ranging from 1- 5mM were found to decrease the initial rate by 10 - 30% but increasing cellobiose concentrations from 5 to 60 mM did not cause a further decline in initial rates, clearly ruling out classical competitive inhibition as a possible mechanism. No definitive correlation was observed between binding and cellobiose concentrations for both enzymes indicating that the presence of cellobiose does not lead to significant enhancement or inhibition of binding.
Download or read book Computational and Experimental Investigation of the Enzymatic Hydrolysis of Cellulose written by Prabuddha Bansal and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The enzymatic hydrolysis of cellulose to glucose by cellulases is one of the major steps in the conversion of lignocellulosic biomass to biofuel. This hydrolysis by cellulases, a heterogeneous reaction, currently suffers from some major limitations, most importantly a dramatic rate slowdown at high degrees of conversion in the case of crystalline cellulose. Various rate-limiting factors were investigated employing experimental as well as computational studies. Cellulose accessibility and the hydrolysable fraction of accessible substrate (a previously undefined and unreported quantity) were shown to decrease steadily with conversion, while cellulose reactivity, defined in terms of hydrolytic activity per amount of actively adsorbed cellulase, remained constant. Faster restart rates were observed on partially converted cellulose as compared to uninterrupted hydrolysis rates, supporting the presence of an enzyme clogging phenomenon. : Cellulose crystallinity is a major substrate property affecting the rates, but its quantification has suffered from lack of consistency and accuracy. Using multivariate statistical analysis of X-ray data from cellulose, a new method to determine the degree of crystallinity was developed. Cel7A CBD is a promising target for protein engineering as cellulose pretreated with Cel7A CBDs exhibits enhanced hydrolysis rates resulting from a reduction in crystallinity. However, for Cel7A CBD, a high throughput assay is unlikely to be developed. In the absence of a high throughput assay (required for directed evolution) and extensive knowledge of the role of specific protein residues (required for rational protein design), the mutations need to be picked wisely, to avoid the generation of inactive variants. To tackle this issue, a method utilizing the underlying patterns in the sequences of a protein family has been developed.
Download or read book Single Molecule Study of Cellulase Hydrolysis of Crystalline Cellulose written by and published by . This book was released on 2009 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cellobiohydrolase-I (CBH I), a processive exoglucanase secreted by Trichoderma reesei, is one of the key enzyme components in a commercial cellulase mixture currently used for processing biomass to biofuels. CBH I contains a family 7 glycoside hydrolase catalytic module, a family 1 carbohydrate-binding module (CBM), and a highly-glycosylated linker peptide. It has been proposed that the CBH I cellulase initiates the hydrolysis from the reducing end of one cellulose chain and successively cleaves alternate ß-1,4-glycosidic bonds to release cellobiose as its principal end product. The role each module of CBH I plays in the processive hydrolysis of crystalline cellulose has yet to be convincingly elucidated. In this report, we use a single-molecule approach that combines optical (total internal reflection fluorescence microscopy or TIRF-M) and non-optical (atomic force microscopy or AFM) imaging techniques to analyze the molecular motion of CBM tagged with green fluorescence protein (GFP) and to investigate the surface structure of crystalline cellulose and changes made in the structure by CBM and CBH I. Preliminary results reveal a confined nanometer-scale movement of the TrCBM1-GFP bound to cellulose, decreases in cellulose crystal size, and increases in surface roughness during CBH I hydrolysis of crystalline cellulose.
Download or read book Aqueous Pretreatment of Plant Biomass for Biological and Chemical Conversion to Fuels and Chemicals written by Charles E. Wyman and published by John Wiley & Sons. This book was released on 2013-03-27 with total page 597 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plant biomass is attracting increasing attention as a sustainable resource for large-scale production of renewable fuels and chemicals. However, in order to successfully compete with petroleum, it is vital that biomass conversion processes are designed to minimize costs and maximize yields. Advances in pretreatment technology are critical in order to develop high-yielding, cost-competitive routes to renewable fuels and chemicals. Aqueous Pretreatment of Plant Biomass for Biological and Chemical Conversion to Fuels and Chemicals presents a comprehensive overview of the currently available aqueous pretreatment technologies for cellulosic biomass, highlighting the fundamental chemistry and biology of each method, key attributes and limitations, and opportunities for future advances. Topics covered include: • The importance of biomass conversion to fuels • The role of pretreatment in biological and chemical conversion of biomass • Composition and structure of biomass, and recalcitrance to conversion • Fundamentals of biomass pretreatment at low, neutral and high pH • Ionic liquid and organosolv pretreatments to fractionate biomass • Comparative data for application of leading pretreatments and effect of enzyme formulations • Physical and chemical features of pretreated biomass • Economics of pretreatment for biological processing • Methods of analysis and enzymatic conversion of biomass streams • Experimental pretreatment systems from multiwell plates to pilot plant operations This comprehensive reference book provides an authoritative source of information on the pretreatment of cellulosic biomass to aid those experienced in the field to access the most current information on the topic. It will also be invaluable to those entering the growing field of biomass conversion.
Download or read book Cellulose Hydrolysis written by Liang-tseng Fan and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent economic trends, especially the worldwide decline in oil prices, and an altered political climate in the United States have combined to bring about major reductions in research on renewable energy resources. Yet there is no escaping the "facts of life" with regard to these resources. The days of inexpensive fossil energy are clearly numbered, the credibility of nuclear energy has fallen to a new low, and fusion energy stands decades or more from practical realization. Sooner than we may wish ,we will have to turn to renewable raw materials - plant "biomass" and, especially, wood - as significant suppliers of energy for both industry and everyday needs. It is therefore especially important to have a single, comprehensive and current source of information on a key step in any process for the technological exploitation of woody materials, cellulose hydrolysis. Further more, it is essential that any such treatment be unbiased with respect to the two methods - chemical and biochemical - for the breakdown of cellulose to sugars. Researchers on cellulose hydrolysis have frequently been chided by persons from industry, especially those individuals concerned with determining the economic feasibility of various technological alternatives. They tell us that schemes for the utilization of wood and other such resources fly in the face of economic realities.
Download or read book Biomass Recalcitrance written by Michael Himmel and published by Wiley-Blackwell. This book was released on 2008-06-23 with total page 552 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book examines the connection between biomass structure, ultrastructure, and composition, to resistance to enzymatic deconstruction, with the aim of discovering new cost-effective technologies for biorefineries. It contains chapters on topics extending from the highest levels of biorefinery design and biomass life-cycle analysis, to detailed aspects of plant cell wall structure, chemical treatments, enzymatic hydrolysis, and product fermentation options."--Pub. desc.
Download or read book Bacterial NanoCellulose written by Miguel Gama and published by CRC Press. This book was released on 2016-04-19 with total page 315 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first book dedicated to the potential applications and unique properties of bacterial cellulose (BC), this seminal work covers the basic science, technology, and economic impact of this bulk chemical as well as the companies and patents that are driving the field. It reviews the biosynthesis and properties of BC, including genetics and characterization; discusses the advancing technology as it relates to product development, bioreactors, and production; and analyzes the economic impact of BC on a diverse range of industry applications, including materials and biomaterials, biological and polymer sciences, and electromechanical engineering.
Download or read book Methods to Determine Enzymatic Activity written by Alane Beatriz Vermelho and published by Bentham Science Publishers. This book was released on 2013-11-22 with total page 334 pages. Available in PDF, EPUB and Kindle. Book excerpt: Methods to Determine Enzymatic Activity is a textbook about industrial enzymes. The book features definitions, classifications and applications of selected enzymes important in industry and in biotechnological processes. Analytical methods for these enzymes are also included in the text. The main objective of this textbook is to provide readers information focused on the current analysis methods of enzymatic activity at qualitative and quantitative levels. Each chapter is about one specific enzyme and contains information about its substrate and some biochemical properties. The methodologies are presented as an experimental protocol allowing interested readers to reproduce the experimental methods detailed within the textbook. These protocols contain the principle of the technique, materials, methods, and all steps necessary for the determination of enzyme activity and interpretation of results. Each methodology is illustrated with photos and schemes for a better and clear understanding. This book, therefore, uniquely brings modern analysis techniques of industrial enzymes in a single easy to understand volume. This textbook is suitable for undergraduate enzymology courses and advanced industrial biotechnology and microbiology courses.
Download or read book Cellulose written by Theo G.M. Van De Ven and published by BoD – Books on Demand. This book was released on 2013-08-28 with total page 380 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cellulose is destined to play a major role in the emerging bioeconomy. Awareness of the environment and a depletion of fossil fuels are some of the driving forces for looking at forest biomaterials for an alternative source of energy, chemicals and materials. The importance of cellulose is widely recognized world-wide and as such the field of cellulose science is expanding exponentially. Cellulose, the most abundant biopolymer on earth, has unique properties which makes it an ideal starting point for transforming it into useful materials. To achieve this, a solid knowledge of cellulose is essential. As such this book on cellulose, the first in a series of three, is very timely. It deals with fundamental aspect of cellulose, giving the reader a good appreciation of the richness of cellulose properties. Book Cellulose - Fundamental Aspects is a good introduction to books Cellulose - Medical, Pharmaceutical and Electronic Applications and Cellulose - Biomass Conversion , in which applications of cellulose and its conversion to other materials are treated.
Download or read book Bioassay Techniques for Drug Development written by Atta-ur-Rahman and published by CRC Press. This book was released on 2001-10-04 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt: The goal of an activity-directed isolation process is to isolate bioactive compounds which may provide structural leads of therapeutic importance. Whereas the traditional process of drug development is long and expensive, simple and rapid bioassays can serve as the starting point for drug discovery. This book presents a range of "bench top" bioassa
Download or read book Directed Enzyme Evolution written by Frances H. Arnold and published by Springer Science & Business Media. This book was released on 2008-02-02 with total page 381 pages. Available in PDF, EPUB and Kindle. Book excerpt: Directed evolution comprises two distinct steps that are typically applied in an iterative fashion: (1) generating molecular diversity and (2) finding among the ensemble of mutant sequences those proteins that perform the desired fu- tion according to the specified criteria. In many ways, the second step is the most challenging. No matter how cleverly designed or diverse the starting library, without an effective screening strategy the ability to isolate useful clones is severely diminished. The best screens are (1) high throughput, to increase the likelihood that useful clones will be found; (2) sufficiently sen- tive (i. e. , good signal to noise) to allow the isolation of lower activity clones early in evolution; (3) sufficiently reproducible to allow one to find small improvements; (4) robust, which means that the signal afforded by active clones is not dependent on difficult-to-control environmental variables; and, most importantly, (5) sensitive to the desired function. Regarding this last point, almost anyone who has attempted a directed evolution experiment has learned firsthand the truth of the dictum “you get what you screen for. ” The protocols in Directed Enzyme Evolution describe a series of detailed p- cedures of proven utility for directed evolution purposes. The volume begins with several selection strategies for enzyme evolution and continues with assay methods that can be used to screen enzyme libraries. Genetic selections offer the advantage that functional proteins can be isolated from very large libraries s- ply by growing a population of cells under selective conditions.
Download or read book Cellulose Chemistry and Properties Fibers Nanocelluloses and Advanced Materials written by Orlando J. Rojas and published by Springer. This book was released on 2016-02-25 with total page 341 pages. Available in PDF, EPUB and Kindle. Book excerpt: Vincent Bulone et al.: Cellulose sources and new understanding of synthesis in plants Thomas Heinze et al.:Cellulose structure and properties Thomas Rosenau, Antje Potthast, Ute Henniges et al.: Recent developments in cellulose aging (degradation / yellowing / chromophore formation) Sunkyu Park et al.:Cellulose crystallinity Lina Zhang et al.:Gelation and dissolution behavior of cellulose Yoshiyuki Nishio et al.:Cellulose and derivatives in liquid crystals Alessandro Gandini, Naceur Belgacem et al.:The surface and in-depth modification of cellulose fibers Emily D. Cranston et al.:Interfacial properties of cellulose Herbert Sixta, Michael Hummel et al.Cellulose Fibers Regenerated from Cellulose Solutions in Ionic Liquids Qi Zhou et al.:Cellulose-based biocomposites Orlando Rojas et al.:Films of cellulose nanocrystals and nanofibrils Pedro Fardim et al.:Functional cellulose particles Wadood Hamad et al.:Cellulose Composites
Download or read book Protein Engineering written by Mallorie N. Sheehan and published by Nova Science Publishers. This book was released on 2013-07 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Protein engineering is the process of developing useful or valuable proteins. It is a young discipline, with much research currently taking place into the understanding of protein folding and protein recognition for protein design principles. There are two general strategies for protein engineering. The first is known as rational design, in which the scientist uses detailed knowledge of the structure and function of the protein to make desired changes. The second strategy is known as directed evolution and this is where random mutagenesis is applied to a protein, and a selection regime is used to pick out variants that have the desired qualities. This book presents and reviews important data on protein engineering, such as application of engineered proteins and cell adhesive surfaces as scaffolds or other biomedical devices which has the potential to promote tissue repair and regeneration for a wide variety of tissues including bone and skin.
Download or read book Functional Chitosan written by Sougata Jana and published by Springer Nature. This book was released on 2020-03-05 with total page 489 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thanks to their unique properties, chitosan and chitosan-based materials have numerous applications in the field of biomedicine, especially in drug delivery. This book examines biomedical applications of functional chitosan, exploring the various functions and applications in the development of chitosan-based biomaterials. It also describes the chemical structure of chitosan and discusses the relationship between their structure and functions, providing a theoretical basis for the design of biomaterials. Lastly, it reviews chemically modified and composite materials of chitin and chitosan derivatives for biomedical applications, such as tissue engineering, nanomedicine, drug delivery, and gene delivery.
Download or read book Xylanolytic Enzymes written by Pratima Bajpai and published by Academic Press. This book was released on 2014-02-03 with total page 121 pages. Available in PDF, EPUB and Kindle. Book excerpt: Xylanolytic Enzymes describes the enzyme structure and its interaction with plant cell walls, the properties and production of different enzymes and their application, and the knowledge gathered on the hydrolysis mechanism of hemicellulose. The knowledge gathered about the hydrolysis mechanism of the hemicelluloses, especially xylans, has greatly promoted the rapid application of these enzymes in new areas. Recently there has been much industrial interest in xylan and its hydrolytic enzymatic complex, as a supplement and for the manufacturing of food, drinks, textiles, pulps and paper, and ethanol; and in xylitol production as a fermentation substrate for the production of enzymes. This book describes xylan as a major component of plant hemicelluloses. - Presents a thorough overview of all aspects of xylanolytic enzymes - Gives up-to-date authoritative information and cites pertinent research - Includes studies on xylanase regulation and synergistic action between multiple forms of xylanase
Download or read book Chemistry of Renewables written by Arno Behr and published by Springer Nature. This book was released on 2020-10-29 with total page 391 pages. Available in PDF, EPUB and Kindle. Book excerpt: This textbook introduces the industrial production and processing of natural resources. It is divided into six major topics (fats and oils, carbohydrates, lignin, terpenoids, other natural products, biorefinery), which are divided into a total of 20 chapters. Each chapter is self-contained and therefore a compact learning unit, which can be worked on by students in self-study or presented by lecturers. Clear illustrations, flow diagrams, apparatus drawings and photos facilitate the understanding of the subject matter. All chapters end with a succinct summary, the "Take Home Messages". Each chapter is supplemented by ten short test questions, which can be solved quickly after working through the chapter; the answers are at the end of the book. All chapters contain bibliographical references that focus on essential textbooks and reference works. As a prior knowledge, only basic knowledge of chemistry is required.
Download or read book Sludge Reduction Technologies in Wastewater Treatment Plants written by Paola Foladori and published by IWA Publishing. This book was released on 2010-07-31 with total page 381 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sludge Reduction Technologies in Wastewater Treatment Plants is a review of the sludge reduction techniques integrated in wastewater treatment plants with detailed chapters on the most promising and most widespread techniques. The aim of the book is to update the international community on the current status of knowledge and techniques in the field of sludge reduction. It will provide a comprehensive understanding of the following issues in sludge reduction: principles of sludge reduction techniques; process configurations; potential performance; advantages and drawbacks; economics and energy consumption. This book will be essential reading for managers and technical staff of wastewater treatment plants as well as graduate students and post-graduate specialists.
