scispace - formally typeset
Search or ask a question
Author

Elwyn T. Reese

Other affiliations: National Research Council
Bio: Elwyn T. Reese is an academic researcher from United States Department of the Army. The author has contributed to research in topics: Cellulase & Cellulose. The author has an hindex of 29, co-authored 59 publications receiving 4649 citations. Previous affiliations of Elwyn T. Reese include National Research Council.


Papers
More filters
Journal ArticleDOI
TL;DR: Questions to which the following data are partial answers are asked: How widespread is the ability of microorganisms to utilize soluble cellulose derivatives as carbon sources?
Abstract: The use of soluble cellulose derivatives in the form of gels for pharmaceutical and other purposes depends in part upon the resistance of the preparation to liquefaction. Reports have reached us that products containing soluble carboxymethyl cellulose (CMC) liquefied on standing. From one of the deteriorated samples Woodward (1948) isolated Aspergillus niger and AspergiUus flavus; from another preparation Freeman et al. (1948) obtained gram-negative bacteria, which on reinoculation, again liquefied the CMC. Contaminated hydroxyethyl cellulose preparations behave in a similar fashion. From one sample Harry (1948) isolated two bacterial organisms. In a study of the availability of cellulose derivatives to Myrothecium verrucaria, Siu et al. (1949) found that CMC-Na salt and methocel (soluble methyl cellulose) were metabolized. From our viewpoint several points appeared to require further elucidation. How widespread is the ability of microorganisms to utilize soluble cellulose derivatives as carbon sources? How do the number, nature, and location of the substituents affect the availability of the modified cellulose? And, finally, is there any relationship between the enzymatic hydrolysis of cellulose derivatives and the hydrolysis of cellulose itself? These are the questions to which the following data are partial answers.

666 citations

Journal ArticleDOI
TL;DR: The present study is a reinvestigation of the induction of cellulase, showing that, under certain conditions, some sugars can induce cellulase formation in Trichoderma viride.
Abstract: Cellulase is an adaptive enzyme in most fungi (Reese and Levinson, 1952), although it is constitutive in cellulolytic bacteria (Hammerstrom et al., 1955). Many polysaccharases are adaptive in fungi, including: pentosanase (Simpson, 1954), polygalacturonase (Phaff, 1947), chitinase (Reynolds, 1954), dextranase (Hultin and Nordstr6m, 1949), and xylanase and mannanase (S0rensen, 1952). Since many of these substrates are insoluble, the question arises as to how an insoluble substrate can induce the formation of an extracellular enzyme. Products of polysaceharide hydrolysis can often induce their respective polysaccharases: galacturonic acid for polygalacturonase in Penicilliurn chrysogenum (Phaff, 1947); xylose for pentosanase in several molds (Simpson, 1954); maltose for amylase in Aspergillus niger (Tanabe and Tonomura, 1953); N-acetylglucosamine for chitinase in Aspergillus fumigatus and Myrothecium verrucaria (Reese, unpublished data). The use of the product as an inducer often leads to lower enzyme yields than are obtained with the substrate. In most cellulolytic fungi tested, however, neither glucose nor cellobiose acted as inducers of cellulase (Reese and Levinson, 1952). Further studies relating to this problem showed that, under certain conditions, some sugars can induce cellulase formation in Trichoderma viride. The present study is a reinvestigation of the induction of cellulase. For comparative purposes, some data on amylase production are also included.

552 citations

Journal ArticleDOI
TL;DR: Serratia marcescens was found to be the most active organism of 100 tested for the production of chitinase and Enterobacter liquefaciens produced nearly as much enzyme.
Abstract: Serratia marcescens was found to be the most active organism of 100 tested for the production of chitinase. Enterobacter liquefaciens produced nearly as much enzyme. Under optimal conditions high y...

532 citations

Journal ArticleDOI
TL;DR: Sophorose is a very powerful inducer of cellulase for Trichoderma viride, being 2500 times as active as cellobiose, and modifications of sophorose, such as reduction or glycoside formation, destroy its inducing ability.
Abstract: Mandels, Mary (Quartermaster Research and Engineering Center, Natick, Mass.), Fredrick W. Parrish, and Elwyn T. Reese. Sophorose as an inducer of cellulase in Trichoderma viride. J. Bacteriol. 83:400–408. 1962.—The impurity in glucose responsible for cellulase induction in Trichoderma viride QM 6a has been isolated and characterized as sophorose (2-O-β-d-glucopyranosyl-d-glucose). It is present at 0.0058% in reagent grade glucose. Sophorose is a very powerful inducer of cellulase for Trichoderma viride, being 2500 times as active as cellobiose. Modifications of sophorose, such as reduction or glycoside formation, destroy its inducing ability. The high activity of sophorose as an inducer is specific for T. viride.

345 citations

Journal ArticleDOI
TL;DR: This paper attempts to show thatcellobiose is the natural inducer of cellulase, and that the low enzyme yields obtained in cellobiose cultures are due to inhibitory and inactivating effects resulting from rapid growth on sugar.
Abstract: Cellulase is an adaptive enzyme in fungi. The inducing substrate, cellulose, is insoluble. How then does the induction occur? It is possible that soluble products of enzyme action are the natural inducers of the enzymes that attack insoluble substrates. This theory assumes that small amounts of the inducible enzymes are produced even in the absence of inducer. When substrate is present it is hydrolyzed, the soluble products then enter the cell and induce more enzyme. Examples of products acting as inducers of polysaccharases have been cited in a previous paper (AMandels and Reese, 1957), and cellobiose can act as an inducei of cellulase (Mandels and Reese, 1957; Talboys, 1958). However, the amount of cellulase produced when Trichodermna viride was grown on cellobiose was less than 5 per cent of the yield on cellulose. If products are the natural inducers, why do they induce so poorly? This paper attempts to show that cellobiose is the natural inducer of cellulase, and that the low enzyme yields obtained in cellobiose cultures are due to inhibitory and inactivating effects resulting from rapid growth on sugar.

305 citations


Cited by
More filters
Journal ArticleDOI
TL;DR: A concluding discussion identifies unresolved issues pertaining to microbial cellulose utilization, suggests approaches by which such issues might be resolved, and contrasts a microbially oriented cellulose hydrolysis paradigm to the more conventional enzymatically oriented paradigm in both fundamental and applied contexts.
Abstract: Fundamental features of microbial cellulose utilization are examined at successively higher levels of aggregation encompassing the structure and composition of cellulosic biomass, taxonomic diversity, cellulase enzyme systems, molecular biology of cellulase enzymes, physiology of cellulolytic microorganisms, ecological aspects of cellulase-degrading communities, and rate-limiting factors in nature. The methodological basis for studying microbial cellulose utilization is considered relative to quantification of cells and enzymes in the presence of solid substrates as well as apparatus and analysis for cellulose-grown continuous cultures. Quantitative description of cellulose hydrolysis is addressed with respect to adsorption of cellulase enzymes, rates of enzymatic hydrolysis, bioenergetics of microbial cellulose utilization, kinetics of microbial cellulose utilization, and contrasting features compared to soluble substrate kinetics. A biological perspective on processing cellulosic biomass is presented, including features of pretreated substrates and alternative process configurations. Organism development is considered for "consolidated bioprocessing" (CBP), in which the production of cellulolytic enzymes, hydrolysis of biomass, and fermentation of resulting sugars to desired products occur in one step. Two organism development strategies for CBP are examined: (i) improve product yield and tolerance in microorganisms able to utilize cellulose, or (ii) express a heterologous system for cellulose hydrolysis and utilization in microorganisms that exhibit high product yield and tolerance. A concluding discussion identifies unresolved issues pertaining to microbial cellulose utilization, suggests approaches by which such issues might be resolved, and contrasts a microbially oriented cellulose hydrolysis paradigm to the more conventional enzymatically oriented paradigm in both fundamental and applied contexts.

4,769 citations

Journal ArticleDOI
TL;DR: This review addresses the complex array of glucosinolates, the precursors of isothiocyanates, present in sixteen families of dicotyledonous angiosperms including a large number of edible species including Brassica vegetables.

2,679 citations

Journal ArticleDOI
TL;DR: The semimicro method gives quantitative recovery of purified cellulose from microbiological culture media, and also appears to be satisfactory for cellulOSE from paper pulp.

1,922 citations

Journal ArticleDOI
TL;DR: It is suggested that it is timely to revisit and reinvigorate functional modeling of cellulose hydrolysis and that this would be highly beneficial if not necessary in order to bring to bear the large volume of information available on cellulase components on the primary applications that motivate interest in the subject.
Abstract: Information pertaining to enzymatic hydrolysis of cellulose by noncomplexed cellulase enzyme systems is reviewed with a particular emphasis on development of aggregated understanding incorporating substrate features in addition to concentration and multiple cellulase components. Topics considered include properties of cellulose, adsorption, cellulose hydrolysis, and quantitative models. A classification scheme is proposed for quantitative models for enzymatic hydrolysis of cellulose based on the number of solubilizing activities and substrate state variables included. We suggest that it is timely to revisit and reinvigorate functional modeling of cellulose hydrolysis, and that this would be highly beneficial if not necessary in order to bring to bear the large volume of information available on cellulase components on the primary applications that motivate interest in the subject.

1,852 citations