Sporotrichum Pulverulentum Research Articles

Vanillic acid metabolism by the white-rot fungus Sporotrichum pulverulentum

Vanillic acid metabolism was studied in wild-type Sporotrichum pulverulentum and three different mutants. Vanillic acid was found to be oxidatively decarboxylated to methoxyhydroquinone (MHQ) and simultaneously reduced to vanillin and vanillyl alcohol to different degrees depending upon the cultivation conditions. The reducing pathway cannot be utilized unless the fungus has access to an easily metabolized carbon source such as glucose or cellobiose, while decarboxylation takes place in cultures with only vanillic acid present. Polymerization reactions also occurred in the culture solutions. Some evidence for reoxidation of vanillin and vanillyl alcohol was obtained in vivo, and in vitro experiments using horseradish peroxidase.

Studies of growth conditions in wood for three white‐rot fungi and their cellulaseless mutants

AbstractWhite‐rot fungi, which have the ability to degrade all the wood components including lignin, are of great interest in biotechnological processes based on wood and other lignocellulosic materials. It was demonstrated earlier that enough lignin can be degraded to cause a decrease in the energy demand for production of thermomechanical pulp if wood chips are pretreated by cellulaseless mutants of white‐rot fungi. This paper concerns the growth conditions in wood for three white‐rot fungi and their cellulaseless mutants in order to determine optimal conditions for such pretreatment processes. The pH and temperature optima have been determined as well as the growth rate in wood. The results show that the growth rate in wood. at least for Cel 44 (a cellulaseless mutant of Sporotrichum pulverulentum), is not the rate‐limiting step in delignification. From different mixtures of urea and NH4H2PO4 the optimal nitrogen source was determined for the mutants. The optimal C/N ratio was found to vary between 160/1 and 400/1. It is suggested that the lower the C/N ratio, the faster the growth. It was also demonstrated that both water‐ and acetone‐extractable substances in wood supported the growth of cellulaseless mutants. When some glucose was added to the wood, the weight loss caused by Cel 44 increased. All these observations support earlier findings that lignin in wood cannot be degraded by white‐rot fungi unless a more easily metabolizable carbon source is used simultaneously.

Intracellular quinone reduction in Sporotrichum pulverulentum by a NAD(P)H: Quinone oxidoreductase : Possible role in vanillic acid catabolism

FEBS LettersVolume 108, Issue 1 p. 229-232 Full-length articleFree Access Intracellular quinone reduction in Sporotrichum pulverulentum by a NAD(P)H: Quinone oxidoreductase Possible role in vanillic acid catabolism Correction(s) for this article Intracellular quinone reduction in Sporotrichum pulverulentum by a NAD(P)H: quinone oxidoreductase (1979) Volume 120Issue 1FEBS Letters pages: 157-157 First Published online: November 14, 2001 J.A. Buswell, J.A. Buswell Chemistry Department, Swedish Forest Products Research Laboratory, Box 5604, S-114 86 Stockholm, SwedenSearch for more papers by this authorS. Hamp, S. Hamp Chemistry Department, Swedish Forest Products Research Laboratory, Box 5604, S-114 86 Stockholm, SwedenSearch for more papers by this authorK.-E. Eriksson, K.-E. Eriksson Chemistry Department, Swedish Forest Products Research Laboratory, Box 5604, S-114 86 Stockholm, SwedenSearch for more papers by this author J.A. Buswell, J.A. Buswell Chemistry Department, Swedish Forest Products Research Laboratory, Box 5604, S-114 86 Stockholm, SwedenSearch for more papers by this authorS. Hamp, S. Hamp Chemistry Department, Swedish Forest Products Research Laboratory, Box 5604, S-114 86 Stockholm, SwedenSearch for more papers by this authorK.-E. Eriksson, K.-E. Eriksson Chemistry Department, Swedish Forest Products Research Laboratory, Box 5604, S-114 86 Stockholm, SwedenSearch for more papers by this author First published: December 01, 1979 https://doi.org/10.1016/0014-5793(79)81216-8Citations: 34AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Volume108, Issue1December 01, 1979Pages 229-232 ReferencesRelatedInformation

Aromatic ring cleavage by the white-rot fungus Sporotrichum pulverulentum

FEBS LettersVolume 104, Issue 2 p. 258-260 Full-length articleFree Access Aromatic ring cleavage by the white-rot fungus Sporotrichum pulverulentum J.A. Buswell, J.A. Buswell Chemistry Department, Swedish Forest Products Research Laboratory, Box 5604, S-114 86 Stockholm, SwedenSearch for more papers by this authorK.-E. Eriksson, K.-E. Eriksson Chemistry Department, Swedish Forest Products Research Laboratory, Box 5604, S-114 86 Stockholm, SwedenSearch for more papers by this author J.A. Buswell, J.A. Buswell Chemistry Department, Swedish Forest Products Research Laboratory, Box 5604, S-114 86 Stockholm, SwedenSearch for more papers by this authorK.-E. Eriksson, K.-E. Eriksson Chemistry Department, Swedish Forest Products Research Laboratory, Box 5604, S-114 86 Stockholm, SwedenSearch for more papers by this author First published: August 15, 1979 https://doi.org/10.1016/0014-5793(79)80827-3Citations: 53AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. References 1 R.B. Cain, R.F. Bilton, J. Darrah, Biochem. J., 108, (1968), 797– 828. 2 W. Flaig, K. Haider, Arch. Mikrobiol., 40, (1961), 212– 223. 3 V. Nečesaný, Drev Výskum, 20, (1975), 23– 36. 4 J.A. Buswell, P. Ander, B. Pettersson, K.-E. Eriksson, FEBS Lett., (1979), in press 5 Ander, P., Hatakka, A. and Eriksson, K.-E. unpublished results. 6 T.K. Kirk, L.F. Lorenz, Appl. Microbiol., 26, (1973), 173– 175. 7 P.J. Chapman, D.W. Ribbons, J. Bacteriol., 125, (1976), 985– 998. 8 A.C.H. Rothera, J. Physiol., 37, (1908), 491– 494. 9 W.R. Sistrom, R.Y. Stanier, J. Bacteriol., 66, (1953), 404– 406. 10 S. Dagley, D.T. Gibson, Biochem. J., 95, (1965), 466– 474. 11 A. Gaal, H.Y. Neujahr, J. Bacteriol., 137, (1979), 13– 21. 12 S. Dagley, Adv. Microb. Physiol., 6, (1971), 1– 46. 13 P. Larway, W.C. Evans, Biochem. J., 95, (1965), 52P– 14 Y. Ohta, D.W. Ribbons, FEBS Lett., 11, (1970), 189– 192. 15 R.L. Crawford, P.E. Perkins, FEBS Lett., 4, (1978), 161– 162. 16 V.L. Sparnins, J.J. Anderson, J. Omans, S. Dagley, J. Bacteriol., 136, (1978), 449– 451. Citing Literature Volume104, Issue2August 15, 1979Pages 258-260 ReferencesRelatedInformation

Oxidative decarboxylation of vanillic acid by Sporotrichum pulverulentum

FEBS LettersVolume 103, Issue 1 p. 98-101 Full-length articleFree Access Oxidative decarboxylation of vanillic acid by Sporotrichum pulverulentum J.A. Buswell, J.A. Buswell Chemistry Department, Swedish Forest Products Research Laboratory, Box 5604, S-114 86 Stockholm, SwedenSearch for more papers by this authorP. Ander, P. Ander Chemistry Department, Swedish Forest Products Research Laboratory, Box 5604, S-114 86 Stockholm, SwedenSearch for more papers by this authorB. Pettersson, B. Pettersson Chemistry Department, Swedish Forest Products Research Laboratory, Box 5604, S-114 86 Stockholm, SwedenSearch for more papers by this authorK.-E. Eriksson, K.-E. Eriksson Chemistry Department, Swedish Forest Products Research Laboratory, Box 5604, S-114 86 Stockholm, SwedenSearch for more papers by this author J.A. Buswell, J.A. Buswell Chemistry Department, Swedish Forest Products Research Laboratory, Box 5604, S-114 86 Stockholm, SwedenSearch for more papers by this authorP. Ander, P. Ander Chemistry Department, Swedish Forest Products Research Laboratory, Box 5604, S-114 86 Stockholm, SwedenSearch for more papers by this authorB. Pettersson, B. Pettersson Chemistry Department, Swedish Forest Products Research Laboratory, Box 5604, S-114 86 Stockholm, SwedenSearch for more papers by this authorK.-E. Eriksson, K.-E. Eriksson Chemistry Department, Swedish Forest Products Research Laboratory, Box 5604, S-114 86 Stockholm, SwedenSearch for more papers by this author First published: July 01, 1979 https://doi.org/10.1016/0014-5793(79)81258-2Citations: 57AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Volume103, Issue1July 01, 1979Pages 98-101 ReferencesRelatedInformation

Production , purification and partial characterization of 1,4-beta-glucosidase enzymes from Sporotrichum pulverulentum.

The production of 1,4-β-glucosidase activity by the rot fungus Sporotrichum pulverulentum has been investigated. It was found that cellobiose or cellulose is necessary to cause induction. With cellobiose as sole carbon source only cell-wall-bound enzymes are produced. For extracellular excretion cellulose seems to be a necessary carbon source. The purification procedures, for purification of enzyme activity in the culture solution, involve the following steps: (a) ultrafiltration, (NH4)2SO4 precipitation and dialyses; (b) preparative slab gel isoelectric focusing I, pH range 3–10; (c) phenyl-Sepharose chromatography; (d) preparative slab gel isoelectric focusing II, pH range 3–5. On the phenyl-Sepharose column the β-glucosidase activity was associated with two separable enzyme peaks, enzyme A and B. When these enzymes were subjected to further purification on preparative isoelectric focusing II, enzyme A was split into two peaks, A1 and A2, and enzyme B was split into three peaks, B1, B2 and B3. The significance of the separations is discussed. The isoelectric points of all the enzymes have been determined and found to vary between 4.52 to 5.15. The molecular weights, determined by dodecylsulphate-polyacrylamide gel electrophoresis, vary between 165000 and 182000. The kinetic constants Km and Ki have been determined for enzyme A and B as well as for the cell-bound β-glucosidase activity. Km for cellobiose was for both enzyme A and B higher than Km for p-nitrophenyl β-d-glucoside. Km/Ki of the free enzymes for gluconolactone is approximately 2500 (enzyme B) to 13000 (enzyme A) with cellobiose as substrate.

Cellobiose oxidase, purification and partial characterization of a hemoprotein from Sporotrichum pulverulentum.

An extracellular enzyme which utilizes molecular oxygen to oxidize cellodextrins to the corresponding aldonic acids has been isolated from culture filtrates of the white-rot fungus Sporotrichum pulverulentum. This enzyme, tentatively named cellobiose oxidase, has been highly purified by classical techniques and has been demonstrated to be a glycoprotein with a molecular weight of approximately 93000. Ultraviolet spectra of the enzyme in the presence and absence of substrate are characteristic of a hemoprotein. Acidic hydrolyses of the enzyme followed by a spectrofluorimetric investigation of the hydrolysate has demonstrated the presence of approximately one flavin component per enzyme molecule. The possible role of this complex enzyme in cellulose degradation is discussed.

Regulation of Endo-1,4-beta-glucanase production in Sporotrichum pulverulentum.

Regulation of endo-1,4-β-glucanases in the white-rot fungus Sporotrichum pulverulentum has been investigated using a new, sensitive method. The method is based upon the viscosity-lowering effect of endo-1,4-β-glucanases on solutions of CM-cellulose. The effect of inducers and repressors can be determined whether the enzymes are localized on the cell wall surfaces or are released into the surrounding solution. The results show that cellobiose causes induction at concentrations as low as 1 mg/l and that glucose concentrations as low as 50 mg/l cause repression of the enzyme formation. Mixtures of inducer and repressor produce a delayed induction compared with solutions of inducer only. Corresponding studies of the mould Trichoderma viride show that cellobiose is not an efficient inducer. Sophorose, however, causes induction of endo-1,4-β-glucanases at 1 mg/l. In mixtures of sophorose and glucose a delayed induction time is also obtained with this fungus. The comparison between the regulation of endo-1,4-β-glucanases in the two fungi shows several other important differences. Thus the solution with CM-cellulose alone induces enzyme formation in S. pulverulentum but not in T. viride. In our experiments no endo-1,4-β-glucanases were actively excreted into the solution by T. viride. the enzymes were bound to the cell wall. S. pulverulentum, however, released the enzymes into the solution although they first appeared bound to the cell wall. These differences imply that the two fungi in their natural environments assure their nutrition in different ways.

Enzyme mechanisms involved in cellulose hydrolysis by the rot fungus Sporotrichum pulverulentum

AbstractThis article presents a review of the enzyme mechanisms involved in degradation of cellulose by the white‐rot fungus Sporotrichum poulverulentum. The hydrolytic enzymes involved include: (1) five endo‐1,4‐β‐glucanases; (2) one exo‐1,4‐β‐glucanase, and (3) one or several 1,4‐β‐glucosidases. A recently discovered oxidative enzyme of importance in in vitro cellulose degradation seems to be a cellobiose oxidase. An oxidoreductase, cellobiose:quinone oxidoreductase, is of importance both in cellulose and in lignin degradation. Regulatory mechanisms of the extracellular enzyme activities, such as monosugar levels causing catabolite repression of the endoglucanases, have also been investigated. The enzymes used by S. pulverulentum in cellulose hydrolysis are compared to those used by Trichoderma viride. Very similar types of enzymes are used in both cases. However, no oxidative enzyme has so far been found to be involved in extracellular cellulose degradation in the case of T. viride. Recommendations for further research are given.

Cellulose and Lignocellulose Degradation by Thermophilic and Thermotolerant Fungi

Twenty-one species of thermophilic and thermotolerant fungi were tested for the ability to degrade cellulose and lignocellulose. Thielavai thermophila is newly described as cellulolytic. Only Chrysosporium pruinosum and Sporotrichum pulverulentum were found to degrade lignocellulose extensively. In a number of cases the moisture content of the solid substrate influenced degradation by the species tested.

Selective Degradation of Wood Components by White‐Rot Fungi

AbstractIn order to find naturally occurring white‐rot fungi which preferentially degrade lignin. 25 different species of such fungi were cultivated on pine wood blocks and on kraft lignin agar plates with and without cellulose. Due to differences in phenol oxidase reactions on the kraft lignin agar plates, the 25 fungi could be divided into two groups, 1 and 2, which also differed in other properties. The three Group I fungi Sporotrichum pulverulentum, Phanerochaete sp. L1 and Polyporus dichrous produced high levels of endo‐l,4‐β‐glucanase and cellobiose:quinone oxidoreductase in shaking cellulose flasks and a low level of phenol oxidase in standing wood meal flasks, The four fungi Merulius tremellosus, Phlebia radiata, Pycuoporus cinnabarinus and Pleurotus ostreatus from Group 2, on the other hand, produced low levels of endo‐1,4‐β‐glucanase and cellobiose:.quinone oxidoreductase in the cellulose. flasks and a high level of phenol oxidase in the wood meal flasks.Analyses of pine wood blocks degraded by the above‐mentioned fungi in the presence of either malt extract, asparagine or NH4H2PO4 revealed that malt extract gave good lignin degradation. In the presence of this nutrient source. P. cinnabarinus, at 3.4% weight loss, even degraded 12.5% lignin without loss of cellulose or mannan. No common degradation pattern was, however, obtained using mall extract, asparagine or NH4H2PO4, It is suggested that while‐rot fungi, which preferentially degrade lignin, may be found among Group 2 fungi producing large amounts of phenol oxidases.

The importance of phenol oxidase activity in lignin degradation by the white-rot fungus Sporotrichum pulverulentum

The lignin degradation abilities of wildtype, a phenol oxidase-less mutant and a phenol oxidase-positive revertant of Sporotrichum pulverulentum were compared to determine if phenol oxidase activity is necessary for lignin degradation by white-rot fungi. The phenol oxidase-less mutant was unable to degrade kraft lignin or wood. The phenol oxidase-positive revertant, however, regained the ability of the wildtype to degrade kraft lignin and all of the major components of wood. It was found that kraft lignin and lignin-related phenols decreased cellulase and xylanase production by the phenol oxidase-less mutant. Addition of highly purified laccase increased the production of endo-1,4-β-glucanase in the phenol oxidase-less mutant in the presence of vanillic acid and kraft lignin. After addition of laccase to kraft lignin agar plates, the phenol oxidase-less mutant could degrade kraft lignin.

Extracellular enzyme system utilized by the fungus Sporotrichum pulverulentum (Chrysosporium lignorum) for the breakdown of cullulose. Functional characterization of five endo-1,4-beta-glucanases and one exo-1,4-beta-glucanase.

A strong synergistic response was observed between the five endo-1,4-beta-glucanases and the exo-1,4-beta-glucanase obtained from culture solutions of the rot fungus Sporotrichum pulverulentum (formerly called Chrysosporium lignorum), when these enzymes were allowed to degrade de-waxed cotton and Avicel. No synergism was observed if Walseth cellulose, an acid-swollen cullulose, was used. If de-waxed cotton was pretreated with endo-1,4-beta-glucanases, the exo-1,4-beta-glucanase enzyme released much more degradation products than from an untreated cotton...

Submerged cultivation of a thermotolerant basidiomycete on cereal flours and other substrates

AbstractThe imperfect state, Sporotrichum pulverulentum, of thecellulolytic basidiomycete Phanerochaete chrysosporiumhas been grown on barley flour and other agricultural products in shake cultures, in an air‐lift fermentor, and in stirred fermentors. The growth morphology varied with cultivation conditions, but it was possible to maintain heavy suspensions of loosely associated mycelia in fermentors. The fungus can grow in temperatures up to 40°C and use ammonium salts or organic nitrogen sources to convert sugars, starch, pectin, and various seed residues to a biomass containing 30–40% protein with a favorable amino acid composition. Serial cultures were grown on flours under conditions where the larger part of the culture was withdrawn and replaced with new medium every, or every other, day. The mycelia are easy to harvest by filtration and have several properties which make the product attractive as a potential food ingredient.

Fermentation of waste mechanical fibers from a newsprint mill by the rot fungus Sporotrichum pulverulentum

AbstractThe growth and protein production of Sporotrichum pulverulentum, formerly called Chrysosporium lignorum, have been studied in submerged cultures using lignin‐containing waste fibers from a newsprint mill as the only carbon source. The influence of different nitrogen sources on the growth parameters has been particularly investigated. The regulation of the production of extracellular enzymes and their interaction with the fibers is discussed. Experiments with cellulose of different degrees of polymerization and crystallinities showed that the protein content in the residual substance decreased, particularly when the crystallinity increased. When the highly crystalline powder cellulose was used as carbon source, the protein content in the residual substance was only 6% and with the mechanical waste fibers 14%. The results obtained demonstrate that the more complex the carbon source the more difficult it is to digest and the more enzyme has to be produced for its degradation. This puts a heavy burden on the protein synthesizing mechanism. Utilizing results from other work, where the endo‐ and exo‐l, 4‐β‐glucanases produced by S. pulverulentum for the degradation of cellulose have been quantitatively purified, it has been calculated that the extracellular enzymes under these conditions can together account for approximately 30% of the protein in the mycelium. The endo‐ and exo‐1,4‐β‐glucanases account for up to 55% of the extracellular protein.Certain possibilities of producing a final product with a high protein content using complex carbon sources are also mentioned.

Extracellular Enzyme System Utilized by the Fungus Sporotrichum pulverulentum (Chrysosporium lignorum) for the Breakdown of Cellulose

Five endo-1,4-beta-glucanases (EC 3.2.1.4) have been separated from culture solutions OF THE ROT FUNGUS Sporotrichum pulverulentum (formerly called Chrysosporium lignorum) grown on powder cellulose as the sole carbon source. They have been extensively purified and characterized with regard to some physicochemical properties. The purifications have been carried out on a quantitative basis, the purity of the enzymes being tested in several ways. After purification they all showed one single protein band in analytical polyacrylamide electrophoresis, on dodecyl-sulphate gels and in analytical isoelectric focusing on flat-bed polyacrylamide gels. One exo-1,4-beta-glucanase has also been identified in the culture solution and separated from the endo-1,4-beta-glucanases. From the data obtained during the quantitative purification it has been possible to calculate that the ratio of activity between the five endoglucanases T1, T2a, T2b, T3a, and T3b in the culture solutions is 4:1:1:1:1. It has also been calculated that the weight ratio endoglucanase protein to exoglucanase protein is approximately 1:1. Flat-bed isoelectric focusing has been used for the identification of the individual endoglucanases and a new zymogram technique, useful for studies of carbohydrases in general, has been developed. The molecular weights, determined by ultracentrifugation, and calculated on the basis of a knowledge of the amino acid composition and carbohydrate content vary between 28200 and 37500. Small but significant differences in the amino acid compositions of the different endoglucanases have been found. The carbohydrate content varies between 0 and 10.5%, all but one of the enzymes being glycoproteins. For two of these the exact carbohydrate composition has been determined. Enzyme T1 contains 2 glucose and 19 mannose units per enzyme molecule while enzyme T2b contains 5 mannose, 7 galactose, 1 glucose and 1 arabinose unit per molecule.

Extracellular enzyme system utilized by the fungus Sporotrichum pulverulentum (Chrysosporium lignorum) for the breakdown of cellulose. 2. Activities of the five endo-1,4-beta-glucanases towards carboxymethylcellulose.

A complementary discussion is given of an earlier presented theory for viscometric determination of enzymic activity towards polymer substrates. Five different, purified endo-1,4-beta-glucanases from the fungus Sporotrichum pulverulentum have been characterised with respect to their molecular activities(Am) and Michaelis-Menten constants (Km). The errors in the Am and Km values are discussed. The Am value seems to be more valuable as a distinguishing parameter than the Km value.

Extracellular Enzyme System Utilized by the Fungus Sporotrichum pulverulentum (Chrysosporium lignorum) for the Breakdown of Cellulose

An exo-1,4-beta-glucanase from culture solution of the rot fungus Sporotrichum pulverulentum (formerly called Chrysosporium lignorum) grown on powder cellulose as the sole carbon source has been extensively purified and characterized with respect to some physico-chemical properties. The purification has been carried out in a five-step procedure comprising chromatography on DEAE-Sephadex, gel filtration on polyacrylamide P-150, activation on a Dowex 2-X8 anion exchanger, chromatography on Concanavalin A-Sepharose and chromatography on SP-Sephadex. The purified enzyme was found to be pure and homogeneous by analytical polyacrylamide electrophoresis, by electrophoresis on dodecylsulphate gels and by analytical polyacrylamide electrophoresis, by electrophoresis on dodecylsulphate gels and by analytical isoelectric focusing. A single symmetrical peak was obtained with the free zone electrophoresis method. The purification factor is about 15 and the yield of exo-1,4-beta-glucanase activity 7%. After purification, the enzyme showed no viscosity-decreasing activity towards carboxymethyl-cellulose solutions. The exo-1,4-beta-glucanase was isoelectric at pH 4.3 (4 degrees C). A molecular weight of 48600 was calculated on the basis of a knowledge of the partial specific volume, ultracentrifugation data and the amino acid composition. The enzyme contained no carbohydrate.

Purification and Properties of Cellobiose:Quinone Oxidoreductase from Sporotrichum pulverulentum.

Cellobiose: quinone oxidoreductase was purified by ammonium sulfate precipitation, SP-Sephadex C-50 chromatography, and hydroxylapatite column chromatography. The purified enzyme is homogeneous by ultracentrifugal and SDS-gel electrophoretic analyses. The enzyme is a flavoprotein with FAD as the prosthetic group and produces cellobiono-delta-lactone as the product of cellobiose oxidation. Cellopentaose is also oxidized but no oxidation of cellulose could be detected. The enzyme oxidizes lactose and 4-beta-glucosylmannose but not 4-beta-mannosylglucose which implicates the C-2-hydroxyl of the non-reducing end of the disaccharide as important for substrate specificity.

Ultrastructure of a Thermotolerant Basidiomycete Possibly Suitable for Production of Food Protein

The imperfect cellulolytic fungus Sporotrichum pulverulentum, which is commonly found growing in wood-chip piles, was grown in submerged culture on wheat shorts and other cereal flours. These substrates were broken down in 1 to 4 days at 30 to 40 C, and the mycelial mass was easily harvested by filtration. Scanning electron micrographs of hyphae in mycelial pellets are presented, and thin sections of conidia and hyphae were studied in a transmission electron microscope. Dolipores in septa of hyphae were observed, and cell walls are shown to be lamellar, which is characteristic of the Basidiomycetes. Actively growing hyphae are full of cytoplasm with numerous mitochondria, whereas old mycelial pellets contain highly vacuolated and almost empty cells.