Production of acetyl xylan esterase by Trichoderma reesei and Schizophyllum commune

1988 ◽  
Vol 34 (6) ◽  
pp. 767-772 ◽  
Author(s):  
P. Blely ◽  
C. R. MacKenzie ◽  
H. Schneider
Keyword(s):  
Trichoderma Reesei ◽  
Esterase Activity ◽  
Extracellular Enzymes ◽  
Carbon Sources ◽  
Schizophyllum Commune ◽  
Resistant Mutant ◽  
Activity Levels ◽  
Acetyl Xylan Esterase ◽  
Low Levels ◽  
C 30

Activity of acetyl xylan esterase, an enzyme that removes acetyl groups from acetyl xylan, was coproduced with that of endoxylanase and endoglucanase in two Trichoderma reesei strains and one Schizophyllum commune strain. The levels of activity of extracellular enzymes were measured during the course of cultivation on different carbon sources. The highest activity levels of acetyl xylan esterase were produced by T. reesei QM 9414 in a xylan plus cellulose medium and by S. commune in a cellulose medium. Both strains produced low levels of acetyl xylan esterase activity in glucose, xylose, and cellobiose media. Schizophyllum commune also produced low levels of acetyl xylan esterase activity in xylan and acetyl xylan media. Trichoderma reesei RUT C-30 behaved like a catabolite repression resistant mutant and produced higher enzyme levels than the QM 9414 strain on all carbon sources examined. Analytical gel electrophoresis and isoelectric focusing demonstrated that the acetyl xylan esterase activity of S. commune was represented as one major form (pI 3.4) which also hydrolyzed 4-methylumbelliferyl acetate. The esterase systems of T. reesei strains were found to be more complex than those of S. commune. The pattern of coproduction of the various activities suggested that acetyl xylan esterase is a component of the cellulolytic system of the fungi tested.

scholarly journals Prospection of Fungal Lignocellulolytic Enzymes Produced from Jatoba (Hymenaea courbaril) and Tamarind (Tamarindus indica) Seeds: Scaling for Bioreactor and Saccharification Profile of Sugarcane Bagasse

2021 ◽  
Vol 9 (3) ◽  
pp. 533
Author(s):  
Alex Graça Contato ◽  
Tássio Brito de Oliveira ◽  
Guilherme Mauro Aranha ◽  
Emanuelle Neiverth de Freitas ◽  
Ana Claudia Vici ◽  
...  
Keyword(s):  
Carbon Sources ◽  
Temporal Analysis ◽  
Industrial Applications ◽  
Lignocellulolytic Enzymes ◽  
Tamarindus Indica ◽  
Acetyl Xylan Esterase ◽  
Trametes Hirsuta ◽  
Hymenaea Courbaril ◽  
The Media ◽  
Main Components

The lignocellulosic biomass comprises three main components: cellulose, hemicellulose, and lignin. Degradation and conversion of these three components are attractive to biotechnology. This study aimed to prospect fungal lignocellulolytic enzymes with potential industrial applications, produced through a temporal analysis using Hymenaea courbaril and Tamarindus indica seeds as carbon sources. α-L-arabinofuranosidase, acetyl xylan esterase, endo-1,5-α-L-arabinanase, β-D-galactosidase, β-D-glucosidase, β-glucanase, β-D-xylosidase, cellobiohydrolase, endoglucanase, lichenase, mannanase, polygalacturonase, endo-1,4-β-xylanase, and xyloglucanase activities were determined. The enzymes were produced for eight filamentous fungi: Aspergillus fumigatus, Trametes hirsuta, Lasiodiplodia sp., two strains of Trichoderma longibrachiatum, Neocosmospora perseae, Fusarium sp. and Thermothelomyces thermophilus. The best producers concerning enzymatic activity were T. thermophilus and T. longibrachiatum. The optimal conditions for enzyme production were the media supplemented with tamarind seeds, under agitation, for 72 h. This analysis was essential to demonstrate that cultivation conditions, static and under agitation, exert strong influences on the production of several enzymes produced by different fungi. The kind of sugarcane, pretreatment used, microorganisms, and carbon sources proved limiting sugar profile factors.

The influence of culture conditions on mycelial structure and cellulase production by Trichoderma reesei Rut C-30

2000 ◽  
Vol 26 (5-6) ◽  
pp. 394-401 ◽  
Author(s):  
F.C. Domingues ◽  
J.A. Queiroz ◽  
J.M.S. Cabral ◽  
L.P. Fonseca
Keyword(s):  
Trichoderma Reesei ◽  
Cellulase Production ◽  
Culture Conditions ◽  
C 30

scholarly journals Feruloyl Esterase Activity of the Clostridium thermocellum Cellulosome Can Be Attributed to Previously Unknown Domains of XynY and XynZ

2000 ◽  
Vol 182 (5) ◽  
pp. 1346-1351 ◽  
Author(s):  
David L. Blum ◽  
Irina A. Kataeva ◽  
Xin-Liang Li ◽  
Lars G. Ljungdahl
Keyword(s):  
Ferulic Acid ◽  
Esterase Activity ◽  
Clostridium Thermocellum ◽  
Plant Cell Wall ◽  
Feruloyl Esterase ◽  
Lower Amount ◽  
Acetyl Xylan Esterase ◽  
Hydrolytic Activities ◽  
C And N ◽  
Cellulose Binding

ABSTRACT The cellulosome of Clostridium thermocellum is a multiprotein complex with endo- and exocellulase, xylanase, β-glucanase, and acetyl xylan esterase activities. XynY and XynZ, components of the cellulosome, are composed of several domains including xylanase domains and domains of unknown function (UDs). Database searches revealed that the C- and N-terminal UDs of XynY and XynZ, respectively, have sequence homology with the sequence of a feruloyl esterase of strain PC-2 of the anaerobic fungusOrpinomyces. Purified cellulosomes from C. thermocellum were found to hydrolyze FAXX (O-{5-O-[(E)-feruloyl]-α-l-arabinofuranosyl}-(1→3)-O-β-d-xylopyranosyl-(1→4)-d-xylopyranose) and FAX3(5-O-[(E)-feruloyl]-[O-β-d-xylopyranosyl-(1→2)]-O-α-l-arabinofuranosyl-[1→3]}-O-β-d-xylopyranosyl-(1→4)-d-xylopyranose), yielding ferulic acid as a product, indicating that they have feruloyl esterase activity. Nucleotide sequences corresponding to the UDs of XynY and XynZ were cloned into Escherichia coli, and the expressed proteins hydrolyzed FAXX and FAX3. The recombinant feruloyl esterase domain of XynZ alone (FAEXynZ) and with the adjacent cellulose binding domain (FAE-CBDXynZ) were characterized. FAE-CBDXynZhad a molecular mass of 45 kDa that corresponded to the expected product of the 1,203-bp gene. Km andV max values for FAX3 were 5 mM and 12.5 U/mg, respectively, at pH 6.0 and 60°C. PAX3, a substrate similar to FAX3 but with ap-coumaroyl group instead of a feruloyl moiety was hydrolyzed at a rate 10 times slower. The recombinant enzyme was active between pH 3 to 10 with an optimum between pH 4 to 7 and at temperatures up to 70°C. Treatment of Coastal Bermuda grass with the enzyme released mainly ferulic acid and a lower amount ofp-coumaric acid. FAEXynZ had similar properties. Removal of the 40 C-terminal amino acids, residues 247 to 286, of FAEXynZ resulted in protein without activity. Feruloyl esterases are believed to aid in a release of lignin from hemicellulose and may be involved in lignin solubilization. The presence of feruloyl esterase in the C. thermocellumcellulosome together with its other hydrolytic activities demonstrates a powerful enzymatic potential of this organelle in plant cell wall decomposition.

scholarly journals Effects of Temperature on the Meiotic Recombination Landscape of the Yeast Saccharomyces cerevisiae

mBio ◽  
2017 ◽  
Vol 8 (6) ◽  
Author(s):  
Ke Zhang ◽  
Xue-Chang Wu ◽  
Dao-Qiong Zheng ◽  
Thomas D. Petes
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Gene Conversion ◽  
Meiotic Recombination ◽  
Hot Spots ◽  
Genetic Maps ◽  
Dna Breaks ◽  
Low Levels ◽  
C 30 ◽  
Recombination Hot Spots ◽  
In Cells

ABSTRACT Although meiosis in warm-blooded organisms takes place in a narrow temperature range, meiosis in many organisms occurs over a wide variety of temperatures. We analyzed the properties of meiosis in the yeast Saccharomyces cerevisiae in cells sporulated at 14°C, 30°C, or 37°C. Using comparative-genomic-hybridization microarrays, we examined the distribution of Spo11-generated meiosis-specific double-stranded DNA breaks throughout the genome. Although there were between 300 and 400 regions of the genome with high levels of recombination (hot spots) observed at each temperature, only about 20% of these hot spots were found to have occurred independently of the temperature. In S. cerevisiae , regions near the telomeres and centromeres tend to have low levels of meiotic recombination. This tendency was observed in cells sporulated at 14°C and 30°C, but not at 37°C. Thus, the temperature of sporulation in yeast affects some global property of chromosome structure relevant to meiotic recombination. Using single-nucleotide polymorphism (SNP)-specific whole-genome microarrays, we also examined crossovers and their associated gene conversion events as well as gene conversion events that were unassociated with crossovers in all four spores of tetrads obtained by sporulation of diploids at 14°C, 30°C, or 37°C. Although tetrads from cells sporulated at 30°C had slightly (20%) more crossovers than those derived from cells sporulated at the other two temperatures, spore viability was good at all three temperatures. Thus, despite temperature-induced variation in the genetic maps, yeast cells produce viable haploid products at a wide variety of sporulation temperatures. IMPORTANCE In the yeast Saccharomyces cerevisiae , recombination is usually studied in cells that undergo meiosis at 25°C or 30°C. In a genome-wide analysis, we showed that the locations of genomic regions with high and low levels of meiotic recombination (hot spots and cold spots, respectively) differed dramatically in cells sporulated at 14°C, 30°C, and 37°C. Thus, in yeast, and likely in other non-warm-blooded organisms, genetic maps are strongly affected by the environment.

Perceived Barriers to Walking in the Neighborhood Environment: A Survey of Middle-Aged and Older Adults

2007 ◽  
Vol 15 (3) ◽  
pp. 318-335 ◽  
Author(s):  
Jill Dawson ◽  
Melvyn Hillsdon ◽  
Irene Boller ◽  
Charlie Foster
Keyword(s):  
Physical Activity ◽  
Older Adults ◽  
Neighborhood Environment ◽  
Perceived Barriers ◽  
Activity Levels ◽  
Environmental Attributes ◽  
Physical Activity Levels ◽  
Health Related ◽  
Low Levels ◽  
The Uk

The authors investigated whether low levels of walking among older adults in the UK were associated with demographic and health characteristics, as well as perceived environmental attributes. Survey data were obtained from self-administered standard questionnaires given to 680 people age 50+ (mean age 64.4 yr) attending nationally led walking schemes. Items concerned with demographic characteristics and perceived barriers to neighborhood walking were analyzed using multiple logistic regression. Citing more than 1 environmental barrier to walking, versus not, was associated with significantly reduced levels of (leisure) walking (MET/hr) in the preceding week (Z = –2.35, p = .019), but physical activity levels overall did not differ significantly (Z = –0.71, p = .48). Citing a health-related barrier to walking significantly adversely affected overall physical activity levels (Z = –2.72, p = .006). The authors concluded that, among older people who favor walking, health problems might more seriously affect overall physical activity levels than perceived environmental barriers.

Cloning and molecular analysis of the HAP2 locus: a global regulator of respiratory genes in Saccharomyces cerevisiae

1985 ◽  
Vol 5 (12) ◽  
pp. 3410-3416
Author(s):  
J L Pinkham ◽  
L Guarente
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Molecular Analysis ◽  
Carbon Sources ◽  
Direct Integration ◽  
Global Regulator ◽  
Low Levels ◽  
Gene Maps ◽  
Derivatives Of ◽  
In Cells

We report here the cloning of the HAP2 gene, a locus required for the expression of many cytochromes and respiratory functions in Saccharomyces cerevisiae. The cloned sequences were found to direct integration of a marked vector to the chromosomal HAP2 locus, and derivatives of these sequences were shown to yield chromosomal disruptions with a Hap2- phenotype. The gene maps 18 centimorgans centromere proximal to ade5 on the left arm of chromosome VII, distinguishing it from any other previously characterized nuclear petite locus. The HAP2 locus encodes a 1.3-kilobase transcript which is present at extremely low levels and which is derepressed in cells grown in media containing nonfermentable carbon sources. Levels of HAP2 mRNA are not reduced in strains bearing a mutation at the HAP3 locus, which is also required for expression of respiratory functions. Models outlining possible interactions of the products of the HAP2 and HAP3 genes are presented.

scholarly journals Physical activity trajectories following gynecological cancer: results from a prospective, longitudinal cohort study

2020 ◽  
Vol 30 (11) ◽  
pp. 1784-1790
Author(s):  
Steven Fleming ◽  
Tamara Jones ◽  
Monika Janda ◽  
Dimitrios Vagenas ◽  
Leigh Ward ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Physical Activity ◽  
Endometrial Cancer ◽  
Gynecological Cancer ◽  
Activity Levels ◽  
Physical Activity Levels ◽  
Low Levels ◽  
The Relationship ◽  
Over Time

BackgroundParticipating in physical activity after a diagnosis of cancer is associated with reduced morbidity and improved outcomes. However, declines in, and low levels of, physical activity are well documented in the broader cancer population, but with limited evidence following gynecological cancer.ObjectiveTo describe physical activity levels from before and up to 2 years after gynecological cancer surgery; to explore the relationship between physical activity patterns and quality of life; and to describe characteristics associated with physical activity trajectories post-gynecological cancer.MethodsWomen with gynecological cancer (n=408) participated in a prospective study that assessed physical activity and quality of life pre-surgery (baseline), at 6 weeks, and 3, 6, 9, 12, 15, 18 and 24 months post-surgery. Validated questionnaires were used to assess physical activity (Active Australia Survey) and quality of life outcomes (Functional Assessment of Cancer Therapy-General). Generalized estimating equation modeling, group-based trajectory analysis, and analysis of variance were used to identify physical activity levels over time, to categorize women into physical activity trajectory groups, and to assess the relationship between physical activity levels and quality of life, respectively.ResultsWomen had a mean±SD age of 60±11.4 years at diagnosis, with the majority diagnosed with endometrial cancer (n=235, 58%) or stage I disease (n=241, 59%). Most women (80%) started with and maintained low levels of physical activity (1–10 metabolic equivalent task hours per week), reported no physical activity throughout the follow-up period, or reduced physical activity levels over time. Only 19% of women maintained or doubled physical activity levels, so that by 24 months post-diagnosis they were engaging in sufficient levels of physical activity. Women with endometrial cancer (58% of the sample) were more likely to be overweight or obese and to report low levels of physical activity or none at all. Higher physical activity levels were associated with higher quality of life (p<0.05).ConclusionThe low baseline and surveillance levels of physical activity show that the vast majority of gynecological cancer survivors have the ability to improve their physical activity levels. Integration of physical activity advice and support into standard care could lead to gains in quality of life during gynecological cancer survivorship.

scholarly journals ABC Transporters Required for Hexose Uptake byClostridium phytofermentans

2019 ◽  
Vol 201 (15) ◽  
Author(s):  
Tristan Cerisy ◽  
Alba Iglesias ◽  
William Rostain ◽  
Magali Boutard ◽  
Christine Pelle ◽  
...  
Keyword(s):  
Abc Transporters ◽  
Extracellular Enzymes ◽  
Plant Biomass ◽  
Carbon Sources ◽  
Anaerobic Bacteria ◽  
Model Organism ◽  
Industrial Transformation ◽  
Content Type ◽  
Plant Matter

ABSTRACTThe mechanisms by which bacteria uptake solutes across the cell membrane broadly impact their cellular energetics. Here, we use functional genomic, genetic, and biophysical approaches to reveal howClostridium(Lachnoclostridium)phytofermentans, a model bacterium that ferments lignocellulosic biomass, uptakes plant hexoses using highly specific, nonredundant ATP-binding cassette (ABC) transporters. We analyze the transcription patterns of its 173 annotated sugar transporter genes to find those upregulated on specific carbon sources. Inactivation of these genes reveals that individual ABC transporters are required for uptake of hexoses and hexo-oligosaccharides and that distinct ABC transporters are used for oligosaccharides versus their constituent monomers. The thermodynamics of sugar binding shows that substrate specificity of these transporters is encoded by the extracellular solute-binding subunit. As sugars are not phosphorylated during ABC transport, we identify intracellular hexokinases based onin vitroactivities. These mechanisms used byClostridiato uptake plant hexoses are key to understanding soil and intestinal microbiomes and to engineer strains for industrial transformation of lignocellulose.IMPORTANCEPlant-fermentingClostridiaare anaerobic bacteria that recycle plant matter in soil and promote human health by fermenting dietary fiber in the intestine.Clostridiadegrade plant biomass using extracellular enzymes and then uptake the liberated sugars for fermentation. The main sugars in plant biomass are hexoses, and here, we identify how hexoses are taken in to the cell by the model organismClostridium phytofermentans. We show that this bacterium uptakes hexoses using a set of highly specific, nonredundant ABC transporters. Once in the cell, the hexoses are phosphorylated by intracellular hexokinases. This study provides insight into the functioning of abundant members of soil and intestinal microbiomes and identifies gene targets to engineer strains for industrial lignocellulosic fermentation.

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