Chrysoporthe Cubensis Research Articles

Evaluation of lignocellulolytic fungal enzymes for eucalyptus wood degradation

Planted forests consist of areas of wood cultivation destined for various commercial applications. The remaining stumps and roots constitute obstacles to the passage of machines and implements to news cycles of cultural management. To overcome the disadvantages of mechanical stump removal, this study aimed to prospect and analyze the lignocellulolytic enzyme profile of 11 fungi isolated from wood and evaluate their ability for in vitro eucalyptus chips degradation. The fungi were cultivated in semi-solid media in 5 different biomasses, which were chemically characterized, for 5 and 8 days. The fungi Hypoxylon sp. and Aspergillus sydowii demonstrated greater activities for some enzymes, while Chrysoporthe cubensis demonstrated interesting activities for most of them, such as 1.3, 2.8, and 1.6 U.mL−1 for FPase, endoglucanase, and β-glucosidase, respectively. The enzymatic extract of C. cubensis, selected for Eucalyptus sp. wood chips hydrolysis, at 20 FPU.g−1 of chip, promoted an increase of reducing sugars to up to 160.3 mmol.L−1 in 10 days. Moreover, it released higher glucose (17.6 g.L−1) and xylose (7.6 g.L−1) amounts compared to the commercial cocktail. Microscopic analysis suggested changes in the structure and constituents by enzymes, which confirms the potential of C. cubensis enzymatic extract for wood degradation.

Comparative analysis of Chrysoporthe cubensis exoproteomes and their specificity for saccharification of sugarcane bagasse

The phytopathogenic fungus Chrysoporthe cubensis is a relevant source of lignocellulolytic enzymes. This work aimed to compare the profile of lignocellulose-degrading proteins secreted by C. cubensis grown under semi-solid state fermentation using wheat bran (WB) and sugarcane bagasse (SB). The exoproteomes of the fungus grown in wheat bran (WBE) and sugarcane bagasse (SBE) were qualitative and quantitatively analyzed by liquid chromatography-electrospray ionization tandem mass spectrometry (LC–ESI–MS/MS). Data are available via ProteomeXchange with identifier PXD046075. Label-free proteomic analysis of WBE and SBE showed that the fungus produced a spectrum of carbohydrate-active enzymes (CAZymes) with exclusive characteristics from each extract. While SBE resulted in an enzymatic profile directed towards the depolymerization of cellulose, the enzymes in WBE were more adaptable to the degradation of biomass rich in hemicellulose and other non-lignocellulosic polymers. Saccharification of alkaline pre-treated sugarcane bagasse with SBE promoted glucose release higher than commercial cocktails (8.11 g L−1), while WBE promoted the higher release of xylose (5.71 g L−1). Our results allowed an in-depth knowledge of the complex set of enzymes secreted by C. cubensis responsible for its high lignocellulolytic activity and still provided the identification of promising target proteins for biotechnological applications in the context of biorefinery.

Characterisation of Chrysoporthe cubensis and Chrysoporthe deuterocubensis, the Stem Canker Diseases of Eucalyptus spp. in a Forest Plantation in Malaysia

Commercial plantations of Eucalyptus species have been established in Malaysia, especially during the past 10 years, with the aim of sustaining the supply of wood and timber products for industrial use in Malaysia. As part of an assessment of fungal diseases affecting Eucalyptus species in four regions in Malaysia, including Kelantan, Pahang, Sabah, and Selangor, stem canker disease was discovered to be a widespread disease infecting Eucalyptus species in Malaysia. This study aimed to identify the fungus-causing stem canker disease, test its pathogenicity in Eucalyptus, and determine the mating type of isolates from the infected trees. The fungi were identified based on morphology and through comparisons of DNA sequence data from the ITS, β-tubulin 2 gene, and TEF-1α gene regions. Phylogenetic analyses showed that the causal agent of the stem canker was Chrysoporthe cubensis infecting Eucalyptus plantations in Pahang and Chrysoporthe deuterocubensis infecting Eucalyptus plantations in Kelantan, Sabah, and Selangor. We believe this is the first report of Chrysoporthe cubensis-infected Eucalyptus in Malaysia and Southeast Asia, while Chrysoporthe deuterocubensis is the first-reported species infecting Eucalyptus pellita in Malaysia. Moreover, the fact that the mating-type MAT1-1 and MAT1-2 genes and the pheromone genes ppg1, ppg2, pre1, and pre2 were identified in all isolates indicates that Chrysoporthe cubensis and Chrysoporthe deuterocubensis are homothallic mating systems. Pathogenicity was tested on a 3-year-old standing tree, 1-year-old seedling, and detached healthy leaves, which were re-isolated for fulfilling Koch’s postulates. In pathogenicity trials, both Chrysoporthe cubensis and Chrysoporthe deuterocubensis gave rise to lesions on wounded Eucalyptus. Both Chrysoporthe spp. were equally pathogenic to Eucalyptus urograndis and Eucalyptus pellita and should be regarded as a biosecurity concern in Malaysia’s forest plantation industry.

Multicopper oxidase enzymes from Chrysoporthe cubensis improve the saccharification yield of sugarcane bagasse

The genome of phytopathogenic fungus Chrysoporthe cubensis has distinct groups of multicopper oxidase (MCO) coding genes, including new laccases, that could have the potential for biotechnological applications. Here, the complete genomic arsenal of MCOs from C. cubensis was identified and characterized. Laccases were induced, purified from the fungal crude extract, and these enzymes' potential to improve the sugarcane bagasse saccharification was tested. In silico genomic analysis revealed 13 MCOs classified as fungal ferroxidases; ascomycete laccases; laccases/ferroxidases; fungal pigments MCOs, and ascorbate oxidases. The C. cubensis cultivation in different lignocellulosic biomass yielded enzymatic extracts more efficiently for sugarcane bagasse saccharification than commercial preparations. The higher laccase activity (4.88 U g-1) was detected in the crude extract of the fungus cultivated on wheat bran and orange peel (3:1), and MCOs with laccase activity were purified from this protein extract. Mass spectrometry using MALDI-TOF/TOF identified two MCOs with 53.4 kDa and 74 kDa. The mixture containing the purified laccases oxidized 91% of the phenolic compounds produced from the alkaline pretreatment of sugarcane bagasse and allowed the improved saccharification yields. These enzymes are promising for application in biomass hydrolysis, especially in the detoxification of phenolic compounds.

The lytic polysaccharide monooxigenases secreted by the fungus Chrysoporthe cubensis: Genomic analysis and impact on sugarcane bagasse saccharification

This work aimed to identify and evaluate the impact of oxidoreductases secreted by Chrysoporthe cubensis COAD 3356 on the saccharification of sugarcane bagasse. Genomic analyses focusing on lytic polysaccharide monooxygenases from Auxiliary Activity family 9 (LPMO9s) indicated fourteen putative LPMO9-coding genes in the C. cubensis genome. The predicted proteins were clustered with other LPMO9s based on sequence similarity. We evaluated if the clusters correlate with LPMO9 function, such as substrate specificity and oxygenation regioselectivity, and with evolutionary features (phylo-specific proteins and the presence of genes coding for LPMO9 redox partners in fungal genomes). There was no apparent connection between the LPMO9 sequences and the evaluated functional properties. On the other hand, we detected clusters containing phylo-specific LPMO9, and a cluster enriched in LPMO9s from fungi with no genes coding for cellobiose dehydrogenase (CDH). Proteomic analysis using LC-MS/MS revealed the presence of seven LPMO9s in C. cubensis exoproteome, in addition to flavin-containing oxidoreductases. Saccharification of alkaline pretreated sugarcane bagasse in aerobic and anaerobic conditions using C. cubensis exoproteome fractions, which contained different LPMO9s, indicated that the CcLPMO9C and CcLPMO9D are better fitted than other LPMO9s secreted by C. cubensis for sugarcane bagasse saccharification.

Genetic variability in populations of Chrysoporthe cubensis and Chr. puriensis in Brazil

Genetic variability in populations of Chrysoporthe cubensis and Chr. puriensis in Brazil

Secretomic insight into the biomass hydrolysis potential of the phytopathogenic fungus Chrysoporthe cubensis

The phytopathogenic fungus Chrysoporthe cubensis has a great capacity to produce highly efficient enzymes for the hydrolysis of lignocellulosic biomass. The bioinfosecretome of C. cubensis was identified by computational predictions of secreted proteins combined with protein analysis using 1D-LC-MS/MS. The in silico secretome predicted 562 putative genes capable of encoding secreted proteins, including 273 CAZymes. Proteomics analysis confirmed the existence of 313 proteins, including 137 CAZymes classified as Glycosyl Hydrolases (GH), Polysaccharide Lyases (PL), Carbohydrate Esterases (CE) and Auxiliary Activities enzymes (AA), which indicates the presence of classical and oxidative cellulolytic mechanisms. The enzymes diversity in the extract shows fungal versatility to act in complex biomasses. This study provides an insight into the lignocellulose-degradation mechanisms by C. cubensis and allows the identification of the enzymes that are potentially useful in improving industrial process of bioconversion of lignocellulose. SignificanceChrysoporthe cubensis is an important deadly canker pathogen of commercially cultivated Eucalyptus species. The effective depolymerisation of the recalcitrant plant cell wall performed by this fungus is closely related to its high potential of lignocellulolytic enzymes secretion. Since the degradation of biomass occurs in nature almost exclusively by enzyme secretion systems, it is reasonable to suggest that the identification of C. cubensis lignocellulolytic enzymes is relevant in contributing to new sustainable alternatives for industrial solutions. As far as we know, this work is the first accurate proteomic evaluation of the enzymes secreted by this species of fungus. The integration of the gel-based proteomic approach, the bioinformatic prediction of the secretome and the analyses of enzymatic activity are powerful tools in the evaluation of biotechnological potential of C. cubensis in producing carbohydrate-active enzymes. In addition, analysis of the C. cubensis secretome grown in wheat bran draws attention to this plant pathogen and its extracellular enzymatic machinery, especially regarding the identification of promising new enzymes for industrial applications. The results from this work allowed for explanation and reinforce previous research that revealed C. cubensis as a strong candidate to produce enzymes to hydrolyse sugarcane bagasse and similar substrates.

Use of Sugar Beet Flour and Wheat Bran as Carbon Source Improves the Efficiency of Chrysoporthe cubensis Enzymes in Sugarcane Bagasse Saccharification

High cost and low efficiency of lignocellulolytic enzymes are the main challenges that must be overcome to make second-generation ethanol more competitive in the fuel market. The cultivation of microorganisms using different agro-industrial wastes as substrates is one of the alternatives to reduce the process costs and obtain more efficient enzyme cocktails in the biomass hydrolysis. Since the fungus Chrysoporthe cubensis has proved to be a promising source of lignocellulolytic enzymes from wheat bran, this study aimed to evaluate the effect of different lignocellulosic materials in its enzyme production and the effectiveness of a new enzymatic cocktail on sugarcane bagasse saccharification. Primarily, this fungus was grown under solid-state fermentation, using wheat bran, elephant grass, or sugarcane bagasse as carbon sources. Afterwards, the wheat bran was combined with sugar beet flour in different ratios, and both were used as carbon sources. The enzymatic profiles were investigated and the most promising enzyme extract was applied to pretreated sugarcane bagasse saccharification. A new cocktail obtained from the combination of wheat bran and sugar beet flour in ratio 1:1 showed the highest activity for almost all enzymes tested and was more efficient than extract obtained with only wheat bran, especially in saccharification of alkaline pretreated sugarcane bagasse, releasing 18 g.L−1 of glucose and 14.8 g.L−1 of xylose, which correspond to 38.5% of cellulose and 61.6% of hemicellulose, respectively. Therefore, the combination of both substrates is an effective strategy to induce Chrysoporthe cubensis to produce a complex and efficient enzymatic cocktail in the biomass hydrolysis.

Recycling of Chrysoporthe cubensis enzymes to overcome the adsorption in lignin and to improve sugarcane bagasse saccharification

Biomass enzymatic hydrolysis efficiency shows some limitations, such as the non-specific adsorption of enzymes in lignin. We evaluated the adsorption of proteins and enzymes from Chrysoporthe cubensis into alkaline and acid pretreated sugarcane bagasse, containing 8.1 and 33.8% of lignin, respectively. The data from Langmuir isotherm showed that at 4 °C, proteins were more adsorbed by acid-treated bagasse, 10.5 mg g−1, while higher adsorption affinity, 2.0 mL mg−1, was determined from alkali-treated bagasse. Similarly, under hydrolytic conditions (50 °C), higher amounts of proteins were adsorbed into acid-treated bagasse, confirming the predominant effect of lignin on protein adsorption. Enzymatic recycling rounds during alkali-treated bagasse saccharification showed that the addition of fresh substrate and enzymes promoted the higher release of glucose and xylose, 40.3 and 38.3 g L−1, respectively. However, the addition of only fresh substrates showed to be efficient for C. cubensis enzymes recovery and substrate hydrolysis, which reduces enzyme consumption and costs.

Chrysoporthe puriensis sp. nov. from Tibouchina spp. in Brazil: an emerging threat to Eucalyptus

The discovery of Cryphonectriaceae and more specifically species related to the Eucalyptus canker pathogen Chrysoporthe cubensis on shrubs and trees in the Melastomataceae, has deepened our understanding of relevant, and potentially globally threatening tree pathogens. Recent isolations of Cryphonectriaceae associated with cankers on Tibouchina spp. in Brazil gave rise to an apparently undescribed species of Chrysoporthe associated with stem and branch cankers that lead to tree death. Cultures of this fungus were subjected to phylogenetic studies based on sequences for the ITS and β-tubulin gene regions. These analyses revealed a novel taxon that is described here as Chrysoporthe puriensis sp. nov., having both sexual and asexual states. Pathogenicity tests on two species of Tibouchina (T. granulosa, T. heteromalla) and hybrids of Eucalyptus grandis x E. urophylla showed that Chr. puriensis can infect and cause disease on all of these trees. It is clearly not only damaging on native Tibouchina spp. where environmental conditions are conducive to disease development, but also potentially threatening to non-native Eucalyptus spp., which form the basis of a major plantation forest industry.

Species of Cryphonectriaceae occupy an endophytic niche in the Melastomataceae and are putative latent pathogens of Eucalyptus

Species of Cryphonectriaceae can occur as asymptomatic fungal endophytes in Melastomataceae trees and shrubs. One hypothesis suggests Chrysoporthe cubensis (Cryphonectriaceae) is an endophyte of the Melastomataceae that has undergone a host switch to infect species of Eucalyptus in South America. The potential for similar host switches by other species of the Cryphonectriaceae is exacerbated by native stands of Melastomataceae that grow alongside commercial plantations of Eucalyptus. We sought to determine the diversity of Cryphonectriaceae endophytic in Melastomataceae trees that occur naturally adjacent to Eucalyptus plantations in Colombia. Branch segments were taken from six different species in three genera of the Melastomataceae. A technique that simulated natural conditions was used to promote fruiting of endophytic Cryphonectriaceae. Taxa were identified using a phylogenetic species concept based on sequence data from the internal transcribed spacer and β-tubulin gene regions. Three species of Cryphonectriaceae, Aurapex penicillata, C. cubensis and C. inopina, were identified. We tested whether these endophytes were potential pathogens of Eucalyptus, and each species was mildly pathogenic. The results showed that at least six species of Melastomataceae are hosts of the Cryphonectriaceae in Colombia. They also emphasize the biosecurity risk of moving superficially healthy stem tissue of the Melastomataceae to new environments.

The mating system of the Eucalyptus canker pathogen Chrysoporthe austroafricana and closely related species

Fungi in the genus Chrysoporthe are economically important canker pathogens of commercially grown Eucalyptus species and native Myrtales. Before the current study, homothallism was widely accepted as the mating system of these species, but this hypothesis could not be fully tested. Using whole genome sequences, we characterized the MAT locus of two C. austroafricana isolates and its sibling species, C. cubensis and C. deuterocubensis. A unique MAT1-2 idiomorph containing a truncated MAT1-1-1 gene, and a MAT1-1-2 gene, was identified in one isolate of C. austroafricana and a MAT1-1 idiomorph was found in the other. The presence of a single idiomorph in each isolate suggests that this fungus is heterothallic. Screening for MAT genes in 65 C. austroafricana isolates revealed a bias towards MAT1-2 idiomorphs suggesting a recent introduction in Eucalyptus species. Chrysoporthe cubensis and C. deuterocubensis are apparently homothallic since all the expected MAT genes were identified in their genome sequences. These findings were corroborated by the expression profiles of pheromone genes and their receptors, which conformed to the expected patterns observed in heterothallic and homothallic isolates. Long terminal repeat sequences (LTRs) and specifically retrotransposons were identified in the MAT locus of C. deuterocubensis and C. cubensis, indicating that the evolution of mating systems in Chrysoporthe species could be mediated by these elements.

Canker disease caused by Chrysoporthe doradensis and C. cubensis on Eucalyptus sp. and Tibouchina spp. in Brazil

Chrysoporthe species are known to cause canker on hosts belonging to Myrtaceae and Melastomataceae families. Cankers occur on tree trunks and branches and may reduce growth and lead to plant death. In this study, the incidence and pathogenicity of Chrysoporthe cubensis and other species causing canker on Eucalyptus sp., Tibouchina heteromalla and T. granulosa were examined. The isolates were collected in Maranhao (MA) and Minas Gerais (MG) in Brazil. Sequence analysis of beta-tubulin and actin genomic regions confirmed the presence of C. cubensis and C. doradensis on clones of the hybrid Eucalyptus grandis x E. urophylla, T. granulosa, and T. heteromalla in Brazil. Morphological characterization enabled the identification of the isolates from both genera primarily based on differences in conidial size and shape. The isolates were pathogenic to ten Eucalyptus clones and Tibouchina plants. Our results contribute new knowledge of Chrysoporthe species causing diseases of woody plants in Brazil of importance to Eucalyptus breeding programs when screening for resistance. Furthermore, this is the first report of C. doradensis infecting Eucalyptus and T. granulosa, as well as the first record of C. cubensis infecting T. heteromalla in Brazil.

Sugarcane bagasse saccharification by purified β-glucosidases from Chrysoporthe cubensis

A set of β-glucosidases from the phytopathogenic fungus Chrysoporthe cubensis was partially purified, characterized and evaluated for its potential application in the process of sugarcane bagasse saccharification. C. cubensis was grown in solid state fermentation (SSF) containing wheat bran as carbon source. The group of β-glucosidases, containing at least three β-glucosidases, was purified through ion exchange and gel filtration chromatography. The set of β-glucosidases exhibited maximum activity at pH 4.0 and 60 °C and showed high thermal stability at 50, 60 and 70 °C. The β-glucosidases were specific for hydrolysis of glucose residues in the β position. The km values of 0.132 and 0.7816 mM were obtained using ρNPβGlc and cellobiose as substrates, respectively. The β-glucosidases were competitively inhibited by glucose, with Ki value of 8.43 mM. Saccharification of pretreated sugarcane bagasse by a commercial enzyme cocktail supplemented with the β-glucosidases promoted efficient release of sugars. Saccharification performed by the Chrysoporthe cubensis extract supplemented with β-glucosidases promoted a higher xylose yield. The results suggest that β-glucosidases from Chrysoporthe cubensis have great potential to be used as a supplement of enzymatic preparations.

Deactivation and activation of lignocellulose degrading enzymes in the presence of laccase.

Cellulase and hemicellulase activities in a 1:1 ratio of enzymes extracted from Chrysoporthe cubensis and Penicillium pinophilum were evaluated in the presence of known monocomponent phenolic inhibitors and also with phenol mixtures derived from alkali pretreated sugarcane bagasse. The cellulolytic activities from C. cubensis:P. pinophilum displayed a much higher tolerance to phenolic inhibitors than equivalent enzyme activities obtained from Trichoderma reesei and Aspergillus niger. Enzymes from T. reesei and A. niger were deactivated at 0.3 and 1.5mg phenols/mg protein, respectively, as reported previously, while enzymes from C. cubensis:P. pinophilum resisted deactivation at 35mg phenols/mg protein. However, tolerance of xylanase with respect to phenols required the presence of laccase. Removal of laccase (enzyme) activity using sodium azide resulted in a 2x higher xylanase deactivation (from 40% to 80%). This paper identifies enzymes that are phenol tolerant, and whose adoption for lignocellulose hydrolysis could contribute to reductions in enzyme loading needed to hydrolyze alkali pretreated lignocellulosic substrates in the presence of lignin derived phenols.

Susceptibility​ ​and​ ​prevalence​ ​of​ ​​Eucalyptus​ ​pellita F.Muell.​ ​to​ ​the​ ​cancer​ ​caused​ ​by​ ​​Chrysoporthe​ ​cubensis (Bruner)​ ​Gryzenhout​ ​&​ ​M.​ ​J.​ ​Wingf.​ ​at​ ​the​ ​Colombian Orinoquia


 
 
 
 Eucalyptus cancer caused by ​Chrysoporthe cubensis is one of the most limiting diseases for ​Eucalyptus ​plantations in the tropical region. In order to confirm the cancer causal fungus observed in the commercial plantations of ​E. pellita in the Colombian Orinoquia and explore the possible difference in the susceptibility of some commercial clones of the region, the pathogen was isolated from diseased tree tissue. The strains obtained were inoculated in young plants belonging to ten clones, including one control of ​E. urophylla under greenhouse conditions. The mean wound length was compared for up to 53 days after inoculation, with two isolates of the pathogen. The prevalence of cancer was also estimated in a 7-year-old ​E. pellita plantation. Based on symptoms, and macro and microscopic morphological characters, the isolates were identified as ​Chrysoporthe cubensis and with the use of the molecular markers ITS5 and ITS4 as ​C. cubensis and ​C. doradensis​. All clones evaluated showed susceptibility to ​Chrysoporthe ​attack. Although eucalyptus cancer is a common disease, this is the first record of ​C. cubensis and ​C. dorandesis in ​E. pellita plantations in Colombian Orinoquia. Given the favorable conditions for the development of the disease in the region, it is recommended to continue the selection​ ​and​ ​evaluation​ ​efforts​ ​to​ ​have​ ​the​ ​disease​ ​tolerant​ ​material.
 
 
 

A Chrysoporthe cubensis enzyme cocktail produced from a low-cost carbon source with high biomass hydrolysis efficiency

Low cost and high efficiency cellulolytic cocktails can consolidate lignocellulosic ethanol technologies. Sugarcane bagasse (SCB) is a low cost agro-industrial residue, and its use as a carbon source can reduce the costs of fungi cultivation for enzyme production. Chrysoporthe cubensis grown under solid state fermentation (SSF) with wheat bran has potential to produce efficient enzymatic extracts for SCB saccharification. This fungus was grown under submersed fermentation (SmF) and SSF with in natura SCB, pretreated with acid or alkali and with others carbon sources. In natura SCB induced the highest carboxymethylcellulase (CMCase), xylanase, β-xylosidase, α-galactosidase and mannanase activities by C. cubensis under SSF. In natura and washed SCB, inducers of enzyme production under SSF, did not induce high cellulases and hemicellulases production by C. cubensis in SmF. The C. cubensis enzymatic extract produced under SSF with in natura SCB as a carbon source was more efficient for lignocelulolic biomass hydrolysis than extracts produced under SSF with wheat bran and commercial cellulolytic extract. Chrysoporthe cubensis showed high potential for cellulases and hemicellulases production, especially when grown under SSF with in natura SCB as carbon source.

Purification and Characterization of Xylanases from the Fungus Chrysoporthe cubensis for Production of Xylooligosaccharides and Fermentable Sugars.

Xylanases from the pathogen fungus Chrysoporthe cubensis were produced under solid state fermentation (SSF) using wheat bran as carbon source. The enzymatic extracts were submitted to ion exchange (Q Sepharose) and gel filtration chromatography methods (Sephadex S-200) for purification. The xylanases were divided into three groups: P1 showed better performance at 60°C and pH 4.0, P2 at 55°C and pH3.0, and P3 at 80°C and pH 3.0. Oat spelt xylan was the best substrate hydrolyzed by P1 and P3, while beechwood xylan was better degraded by P2. Carboxymethyl cellulose (CMC) and p-nitrophenyl-β-D-xylopyranoside (p-NPβXyl) were not hydrolyzed by any of the xylanases. The K M' or K M values, using oat spelt xylan as substrate, were 2.65mg/mL for P1, 1.81mg/mL for P2, and 1.18mg/mL for P3. Xylobiose and xylotriose were the main xylooligosaccharides of oat spelt xylan degradation, indicating that the xylanases act as endo-β-1,4-xylanases. Xylanases also proved to be efficient for hydrolysis of sugarcane bagasse when used as supplement of a commercial cocktail due to the increase of the reducing sugar release.

IMA Genome-F 5: Draft genome sequences of Ceratocystis eucalypticola, Chrysoporthe cubensis, C. deuterocubensis, Davidsoniella virescens, Fusarium temperatum,Graphilbum fragrans, Penicillium nordicum, and Thielaviopsis musarum.

The genomes of Ceratocystis eucalypticola, Chrysoporthe cubensis, Chrysoporthe deuterocubensis, Davidsoniella virescens, Fusarium temperatum, Graphilbum fragrans, Penicillium nordicum and Thielaviopsis musarum are presented in this genome announcement. These seven genomes are from plant pathogens and otherwise economically important fungal species. The genome sizes range from 28 Mb in the case of T. musarum to 45 Mb for Fusarium temperatum. These genomes include the first reports of genomes for the genera Davidsoniella, Graphilbum and Thielaviopsis. The availability of these genome data will provide opportunities to resolve longstanding questions regarding the taxonomy of species in these genera. In addition these genome sequences through comparative studies with closely related organisms will increase our understanding of how these pathogens cause disease.

The influence of pretreatment methods on saccharification of sugarcane bagasse by an enzyme extract from Chrysoporthe cubensis and commercial cocktails: A comparative study

Biomass enzymatic hydrolysis depends on the pretreatment methods employed, the composition of initial feedstock and the enzyme cocktail used to release sugars for subsequent fermentation into ethanol. In this study, sugarcane bagasse was pretreated with 1% H2SO4 and 1% NaOH and the biomass saccharification was performed with 8% solids loading using 10 FPase units/g of bagasse of the enzymatic extract from Chrysoporthe cubensis and three commercial cocktails for a comparative study. Overall, the best glucose and xylose release was obtained from alkaline pretreated sugarcane bagasse. The C. cubensis extract promoted higher release of glucose (5.32g/L) and xylose (9.00g/L) than the commercial mixtures. Moreover, the C. cubensis extract presented high specific enzyme activities when compared to commercial cocktails mainly concerning to endoglucanase (331.84U/mg of protein), β-glucosidase (29.48U/mg of protein), β-xylosidase (2.95U/mg of protein), pectinase (127.46U/mg of protein) and laccase (2.49U/mg of protein).