With respect to secretion by mutants, Schneider et al. Positions of the identified regions are indicated on the enzyme homology models. Trichoderma spp. Trichoderma virens and T. atroviride share 1273 orthologs that are not present in T. reesei, which could thus be part of the factors that make T. atroviride and T. virens mycoparasites Further, 26 out of 48 gene families were found to be expanded in the two mycoparasitic species relative to T. reesei. microplus females treated with B. bassiana B.bAT17 significantly had a lower the amount of ovipositioning and most ticks died before they could begin to oviposit. are found to tolerate toxicants like antibiotics, plant antimicrobial compounds, and synthetic chemicals or contaminants. FIGURE 5.5. By continuing you agree to the use of cookies. From: Biotechnology and Biology of Trichoderma, 2014, Barbara Reithner, Robert L. Mach, in Biotechnology and Biology of Trichoderma, 2014. (2010) added chitin in the production medium and talc formulation of T. harzianum which enhanced the shelf life by 2 months. (2015) and Gong et al. Muthuvelu et al. A hydrophobin-like protein (TasHyd1) from Trichoderma asperellum (Viterbo and Chet, 2006) is found to facilitate root attachment and colonization to the roots; whereas Qid74, a cysteine-rich cell wall protein is identified to have an important role in adherence to hydrophobic surfaces and cellular protection in T. harzianum (Samolski etal., 2012). With respect to these, the three Trichoderma spp. Sriram et al. Therefore, white-rot fungi and brown-rot fungi should have different strategies for using hydrolytic enzymes to degrade cellulose (Hori et al., 2013). This shows that a general increase in the chitinolytic activity of Trichoderma spp.
Evolutionary analysis of Chit36 and ChiJ orthologs. The efficiency as biocontrol agent became completed by an additional local reduction of disease symptoms and a systemic potentiation of PR genes (Shoresh etal., 2005). Both of these chitinases are lacking CBMs.
Adav et al.
In comparison, the mycoparasitic species possess genomes that range between 33.48Mb and 40.98Mb (Table 33.1). Model for the ISR signaling pathway. This suggests that T. atroviride and T. virens may contain an as yet undiscovered reservoir of secondary metabolites, which may contribute to their success as mycoparasites (Kubicek etal., 2011).
Phylogenetic relationships suggest a single neofunctionalization event that resulted in evolution of enzymes with ENGase activity from a chitinase ancestor (Karlsson and Stenlid, 2009). Enhanced Resistance of Plants to Disease Using Trichoderma spp.
With respect to the quantity and quality of secretion by a pure culture, Borin et al. In contrast to chemical and physical treatments, ligninolytic enzymes-mediated lignin degradation is a green approach that presents numerous benefits such as low energy input, mild operational conditions, and circumventing the use of hazardous chemicals [156]. T. versicolor secreted high levels of laccase, Highlighted differences of strategies utilizing hydrolytic enzymes to degrade cellulose among two different lignocellulolytic microorganisms, Highlighted specially expressed proteins among lignocellulolytic strains, Penicillium echinulatum wild-type was more efficient in production of enzymes involved in cellulose and hemicellulose degradation. Identifications of lignocellulolytic enzymes secreted by G. lucidum, 87 proteins were identified, 63 were secretory proteins in F. graminearum, Highlighted 51 variable secreted proteins among six wild-type strains with different host range grown in liquid minimal medium, Highlighted lignocellulose degradation mechanism by filamentous fungi, and indicated each of 20 fungi in test could act as a supplement for industrial T. reesei enzymatic cocktail to improve sugar release, Sugar substrate composition strongly influenced composition of the cellulolytic cocktail secreted by T. reesei in fed-batch mode, Under same condition, A. niger secreted more enzymes (quantitatively and qualitatively) related to biomass degradation than T. reesei, A. niger secreted more enzymes in degradation of (galacto) mannan and xyloglucan, Secretome of T. asperellum contained high diversity of main and side chain hemicellulases and -glucosidases, and an increased abundance of some of these proteins compared with T. reesei, Highlighted importance of low abundant auxiliary proteins for efficient lignocellulose degradation, and differential expressions of pectin-degrading proteins, peptidase and proteases in different substrates, Highlighted new approach for improving cellulose accessibility in biofuel feedstocks, fresh material and cell wall residues from different plants. Genes from Trichoderma as a Source for Improving Plant Resistance to Fungal Pathogen, Advances in Formulation of Trichoderma for Biocontrol, Genome-Wide Approaches toward Understanding Mycotrophic Trichoderma Species. Even when coinoculated with other beneficial microorganism like the AMF, Trichoderma spp. Biofuels are eco-sustainable and possess high-energy proficiency than that to fossil-based fuels.
The second ENGase (Eng18B) does not contain a signal peptide and is therefore an intracellular protein, presumably involved in the endoplasmic reticulum associated protein degradation pathway (ERAD) of misfolded glycoproteins. 
It reduced the benzyl phenyl ether content from 95.90% to 75.63% after 48h agitation in a shaker at 25C. Such studies indicated that T. reesei had seven chromosomes ranging in size from 2.8Mb to 6.9Mb, resulting in a total genome of about 33Mb (Carter et al., 1992; Herrera-Estrella et al., 1993; Mantyla et al., 1992). (2012a) found that glycosyl hydrolases that are secreted by Trichoderma reesei during cellulose and lignocellulose degradation exhibited significantly greater expression than Phanerochaete chrysosporium.
(2013) noted that the secretomes of Clostridium thermocellum ISO1, ISO2 and CthJW vary substantially.
5.4). However, enzymes involved in other parasitehost interactions sometimes evolve rapidly in response to a coevolutionary arms race, resulting in continuous selection for adaptive modifications. Disruption mutants of Eng18B in T. atroviride show defects in vegetative growth, tolerance to abiotic stress, conidiation, chitin utilization and mycoparasitism of Botrytis cinerea (Dubey etal., 2012). C. puteana produced more endoglucanase and xylanase, but barely laccase or manganese-dependent peroxidase. Comparative genome analysis of T. atroviride, T. virens, and T. reesei, revealed that these three Trichoderma species display a remarkable conservation of gene order (7896%), and a lack of active mobile elements (transposons).
facilitate root colonization of their hosts by the production and regulation of hormonal signals. As the main product of photosynthesis, sucrose acts as an important molecule in carbohydrate-mediated signaling in plants and degraded by plant cells to yield a carbon source for microbes during plantmicrobe associations (Koch, 2004). (1993) found that T. harzianum and Trichoderma viride had six chromosomal DNA bands varying in size from 2.2Mb to 7.7Mb, with the total genome sizes estimated to range from 31Mb to 39Mb. Chitinase synthesizing fungi (Conidiobolus coronatus NFCCI 1235, C. couchii NFCCI 719, C. coronatus NFCCI 718, Basidiobolus haptosporus NFCCI, 1922 and Basidiobolus haptosporus NFCCI, 1923) were isolated from the two different genera of fungus, Conidiobolus and Basidiobolus.
A combined analysis of molecular evolution and homology modeling of Ech30 revealed four regions where high sequence diversity was putatively driven by positive selection (Fig.
Maximum hydrolysis of fungal mycelia was noticed with the Aspergillus niger after 72h (Mishra et al., 2011).
Besides a GH18 module, subgroup B chitinases in Trichoderma spp. The molecular mechanisms that govern the recognition and association between Trichoderma and their hosts are still largely unknown. Half of the secondary metabolite gene clusters present in T. virens and T. atroviride are not present in T. reesi, but all those present in the latter were also found in the mycoparasites (Kubicek etal., 2011). Adav et al. Hongliang Guo, Duu-Jong Lee, in Bioresource Technology, 2018. This type of coevolutionary interactions may leave an imprint on the selective signature of the participating enzymes, and the previously mentioned Ech30 is one possible example of this. Disruption of the orthologous gene in N. crassa, gh18-10, results in similar phenotypic effects and a significant reduction in secreted proteins (Tzelepis etal., 2012). (2003) found that dried banana leaves is the best carrier material to support the growth of Trichoderma spp. Saskia CM Van Wees, Corn MJ Pieterse, in Current Opinion in Plant Biology, 2008. FIGURE 5.6. Analyses of plant genotypes, particularly mutants (disrupted, overexpressing or knock out mutants) and transgenics that either do not accumulate or do not respond to SA, JA, ET and other defense-related pathways help elucidate the signaling molecules essential for basal resistance to varying pathogens (Korolev etal., 2008; Salas-Marina etal., 2011; Malmierca etal., 2012). Kandula et al.
Dried conidial pellets of T. harzianum were more effective antagonist formulation than liquid formulation in inhibiting sclerotial germination of Rhizoctonia solani (Cumagun and Ilag, 1998). They can also vary significantly among wild-type strains of the same bacterium, such as Botrytis cinerea wild-type B05.10 and wild-type T4 (Gonzlez-Fernndez et al., 2014). [158] demonstrated the laccase immobilization on ferrite magnetic nanoparticles and copper ferrite magnetic nanoparticles and applied to lignin removal. Trichoderma koningii, on the other hand, suppresses the production of phytoalexins during colonization of Lotus japonicus roots (Masunaka etal., 2011). (2013) also identified differences between the strategies of Hypocrea jecorina and Clostridium thermocellum for using hydrolytic enzymes to degrade cellulose. Blume et al. Trichoderma virens exhibited the highest number (50) of PKS, NRPS and PKSNRPS fusion genes, mainly due to the abundance of NRPS genes. 5.5). Phylogenetic analysis of the available genome sequence data indicates that the powerful antagonists of other fungi, T. atroviride and T. asperellum, are ancestral species, suggesting that mycoparasitism was the ancestral life style of the genus (Kubicek etal., 2011). As compared to the free enzyme, the immobilized biocatalyst showed high potential for lignin removal in sweet sorghum Stover and recycled in eight repeated cycles.
frequently contain a CBM1 module at their C-terminus (Fig. The treatment with the greatest effect was the addition of starch and small amounts of copper with the latter as food base including lowering the pH of the biomass paste to reduce metabolic activity of T. asperellum. Main phenotypic characters are conidial ornamentation and arrangement and branching of the conidiophores.
The relatively low number of subgroup B chitinases in T. reesei is a consequence of the switch from mycoparasitism to a saprotrophic lifestyle (Kubicek etal., 2011), which is accompanied by a loss of endochitinase genes.
Interestingly, conjugated forms of plant hormones accumulating during the priming state support the idea that they can be rapidly hydrolysed to their active forms to respond faster against a pathogenic invasion [5,16].
At the metabolomic level, various amino acid precursors of plant defence metabolites [18] have been shown to accumulate to a higher level following priming with T. asperellum, but also with chemicals such as pipecolic acid [17,19].
Mycoparasitism depends on a combination of events that include lysis of the preys' cell wall (Harman etal., 2004; Howell, 2003; Lorito etal., 2010). [2] It can be distinguished from T. viride by molecular and phenotypic characteristics. does have an effect on its mycoparasitic abilities and underlines the yet unexplored potential of the chitin machinery in Trichoderma. Subgroup B chitinases have a shallower and more open substrate binding site compared with subgroup A chitinases, similar to the related plant (class III) endochitinases. It is known that the addition of a CBM increases the adherence of an enzyme to insoluble substrates because the enzyme does not dissociate from the substrate after successful cleavage, which would normally be the case for proteins with shallow substrates binding site as subgroup B endochitinases. was shown for maize (Zea mays) and cucumber (Cucumis sativus L.), amongst others, which was accompanied by increased production of phytoalexin and plant defense transcripts, as PR genes (Yedidia etal., 1999; Djonovi etal., 2006, 2007).
Muhammad Bilal, Hafiz M.N. Attack by pathogens or insects, as depicted on the right side of the figure, activates defense responses in the plant (yellow arrows), which is accelerated in ISR-primed plants (combined blue and yellow arrows).
In addition, the rampant population growth, and food versus fuel discussion, has diverted the emphasis on the synthesis of biofuel from non-edible feedstock's [153,154]. The secretory strategies of lignocellulose degrading enzymes that are used by various microorganisms, such as those by Ganoderma lucidum (Manavalan et al., 2012) and Fusarium graminearum (Ji et al., 2013), can vary greatly.
As already mentioned, the genome sequence also revealed that 1273 orthologous genes are shared between T. atroviride and T. virens but absent from T. reesei. A. phoenicis and Paecilomyces variotii. The invert emulsion (water-in-oil type) formulation of T. harzianum prolonged the postharvest shelf life of the fruit (Batta, 2007). However, contradictory results have also been obtained: under the same testing conditions Penicillium oxalicum secretes more cellulases than Aspergillus niger and Trichoderma reesei (Glass et al., 2013), but Aspergillus niger secretes more enzymes for xyloglucan conversion than do Penicillium oxalicum and Trichoderma reesei (Gong et al., 2015). Because liquid formulation of Trichoderma spp. Proteomic and metabolomic mechanisms remain poorly understood. (2012a) reached the same conclusion based on their comparative analysis of secretomes for Trichoderma reesei and its mutant Rut C30. Their expression experiments suggest the existence of a sucrose-dependent network in the fungal cells that regulates the symbiotic association between Trichoderma and its host plants. isolated from the rhizosphere of banana from Tamil, India. Saldajeno, M. Hyakumachi, in Biotechnology and Biology of Trichoderma, 2014. White-rot polyporales can produce more diverse lignocellulose degrading enzymes than brown-rot polyporales. The same group provided evidence for the protection of cucumber plants by Trichoderma asperellum T-203 (formerly T. harzianum T-203) against Pseudomonas syringae pv. Recently, Alves et al. lachrymans (Psl) by induction of systemic resistance, since Trichoderma did not antagonize Psl in dual cultures. In mycoparasitic interactions, this may include production of enzyme inhibitors from the fungal prey and modifications of the cell wall structure to avoid damage from chitinases. The biocontrol ability in cucumber was associated with the accumulation of phytoalexins. Christian Joseph R. Cumagun, in Biotechnology and Biology of Trichoderma, 2014. Trichoderma asperellum Samuels, Lieckf & Nirenberg [1] is a species of fungus in the family Hypocreaceae.
Recognition of MAMPs of beneficial rhizosphere-colonizing microorganisms, such as Pseudomonas fluorescens WCS417 or Trichoderma asperellum T34, leads to a local activation of the transcription factor gene MYB72 in the roots.
However, compared with non-primed plants, T. asperellum-inoculated plants that suffered subsequent infection by Pst showed major differences in defence gene expression patterns [17].
Iqbal, in International Journal of Biological Macromolecules, 2021. B. haptosporus NFCCI 1922 hydrolyzed the mycelia of tested fungal isolates as a major carbon source to produce chitinase. (2016) performed comparative secretome analyses of Penicillium echinulatum wild-type 2HH and its mutant strain S1M29, and found that the latter was more efficient than the former in producing enzymes that participate in cellulose and hemicellulose degradation.
As these regions were associated with structural features of the TIM barrel structure of the protein, these differences may represent adaptive adjustments of Chit36 to the fungal environment after the horizontal gene transfer event. Additionally, the negative regulation by two enzymes on the ethylene defense response was abolished after the application of Trichoderma, due to the downregulation of their transcripts. 5.7). Gene expression of ech30 was found to be elevated during growth on fungal cell walls and in mycoparasitism assays (Seidl etal., 2005), which indicates that the function of Ech30 is indeed degradation of fungal cell wall chitin. In general, no conclusions can be drawn from the comparative studies stated above on how different strains would select their strategies to secrete lignocellulose-degrading enzymes. Structural modeling showed that this is due to subtle differences in the substrate binding cleft in comparison to the well characterized plant chitinase hevamine, resulting from small insertions and deletions in loops on the noncatalytic side of the TIM barrel.
Theoretically, several synergistically acting endochitinase isozymes may be equally advantageous for degradation of dead fungal biomass as for the mycoparasitic attack. Thus, mycoparasitism-specific genes arose in a common Trichoderma ancestor and were subsequently lost in T. reesei (Kubicek etal., 2011). (2009) demonstrated that an intracellular invertase from Trichoderma virens (TvInv) is responsible for sucrose hydrolysis and normal growth of T. virens in the presence of sucrose. TABLE 33.1.
Region A (Fig. Several studies on enhanced disease resistance by Trichoderma demonstrated reductions in disease incidence or severity in the upper portion of the plants when the biocontrol Trichoderma strains were only present in the roots, showing a spatial separation of the inducing Trichoderma strains and the challenging pathogens on the same plants.
Further studies on the induction of induced resistance in cucumber by T. asperellum T-203 extended previous investigations by testing gene expression of more components involved in the different defense response pathways. An ATP-binding cassette transporter cell membrane pump characterized in Trichoderma atroviride is believed to be an important component of an extensive and powerful cell detoxification system which explains the ability of the fungus to withstand different chemical stresses (Ruocco etal., 2009). Regions where high amino acid diversity is driven by positive selection are indicated in orange and marked A, B, C and D in a homology model of Ech30. It is furthermore necessary to determine whether the high sequence diversity between orthologs is the result from low selective constraint, i.e.
Using a qRT-PCR approach to analyse selected marker genes, Trichoderma asperellum was described to prime Arabidopsis thaliana defence against virulent Pseudomonas syringae (Pst) without causing major changes in gene expression during the priming phase.
Another type of GH family 18 proteins that are phylogenetically associated with subgroup B is the subgroup B5 ENGases, which have only recently been described in fungi. Growing in bentonitevermiculite formulation also increased the colony forming units of T. harzianum after 8 weeks and provided higher melon shoot weight and higher resistance to Fusarium wilt disease (Martinez-Medina et al., 2009). contained a varying assortment of nonribosomal peptide synthetases (NRPS) and polyketide synthases (PKS). The necessity to degrade this barrier is reflected in the abundance of chitinases and -1,3-glucanases in Trichoderma relative to other fungi. The effective biocontrol strains of Trichoderma spp. ; Lieckfeldt, E.; Nirenberg, H.I.
By using reverse genetic experiments, Vargas etal. Colonization of the plant root system by Trichoderma spp.
The isolate B.bAT17 of Beauveria bassiana highly pathogenic against engorged Rhipicephalus (Boophilus) (R. B) microplus females, resulting in lethal time (LT50 and LT90) of 7.14 and 9.33 days at a concentration of 109 conidia/ml.
This means that the mycoparasitic lifestyle exert selection for increased number of subgroup B endochitinases, possibly as they provide the first attack on the chitin component of the cell wall of the fungal prey that provide exposed chitin polymer ends on which exochitinases can act. Similarly, Herrera-Estrella etal.
Table 2. Most subgroup B chitinases are rather small (3040kDa), but there is in each species one large subgroup B chitinase (ca.
The expansin-like protein swollenin TasSwo (Brotman etal., 2008) and the endopolygalacturonase ThPG1 from T. harzianum (Morn-Diez etal., 2009) were also found to facilitate root penetration. (2018) characterized a ~44kDa chitinase from Aspergillus niveus works well at 65C and pH 5.0. M.G.B. The reason for improved performance is the sustained colonization of T. harzianum SQR-T037 in the rhizosphere soil (Yang et al., 2011). Sriram et al. A corresponding ortholog in A. nidulans, ChiA, was shown to be localized at the tips and branching sites of fungal hyphae, indicating that this protein is involved in cell wall synthesis and remodeling (Yamazaki etal., 2008). Another class of genes of relevance to mycoparasitism are those involved in the formation of secondary metabolites. However, as outlined by Lee (2008), residues important for enzyme properties may be expected to display higher diversity than other positions in closely related orthologs due to selection for modified enzymatic properties between species. Molecular Evolution of Trichoderma Chitinases, Antifungal and insecticidal potential of chitinases: A credible choice for the eco-friendly farming, Biocatalysis and Agricultural Biotechnology, The prime-ome: towards a holistic approach to priming, Harnessing the biocatalytic attributes and applied perspectives of nanoengineered laccasesA review, International Journal of Biological Macromolecules, Proteomic researches for lignocellulose-degrading enzymes: A mini-review, Borin et al. Gene expression of chit36 (chi18-15) is induced by various different stimuli including growth on chitin and fungal cell walls, mycoparasitism and starvation (Viterbo etal., 2002). In such context the phenylalanine ammonia lyase (PAL), which is involved in the secondary metabolite production including phytoalexin, as well as a hydroperoxide lyase (HPL), which is part of the octadecanoic pathway (and indirect also the JA pathway), were induced.
ISR inducibility by Trichoderma was also tested with 36 phytohormone-affected mutants of A. thaliana. Although no subgroup B chitinase that contains a CBM has been biochemically studied so far, addition of cellulose binding domains (CBM1) to Chit33 or Ech42 was shown to enhance the hydrolysis of insoluble substrates (Limon etal., 2001). Auxin-induced modifications in root architecture (e.g. seem to have a role in attenuating plant hormone responses to favor the root colonization process (Martnez-Medina etal., 2011a). The sequenced T. reesei strain shows a saprotrophic lifestyle on decaying wood, so the analysis of newly sequenced Trichoderma genomes (already Trichoderma longibrachiatum, Trichoderma citrinoviride, Trichoderma asperellum and T. harzianum are available at the Mycocosm portal of DOE JGI website) will determine if the selection for high numbers of subgroup B endochitinases is specific for mycoparasitism or if this also applies to the mycotrophic lifestyle.
trichotoxins in Trichoderma asperellum, and trichostromaticins in Trichoderma stromaticum. The biohydrogen production rate and yields were recorded to be 25L H2/L-d, 2.8mol H2/mol reducing sugar, respectively, in a continuous stirred fermenter.
inoculation to be quantified similar to the case of rhizobacteria (van Loon, 2007). These genes include, solute transporters, and several putative oxidoreductases and monooxygenases that may be involved in AMP-activation of acids and phosphopathetheine attachment, and synthesis of isoquinoline alkaloids. Biochemical analysis have revealed local or systemic accumulation of phytoalexins, phenolic compounds, terpenoids, superoxides, or lignifications in plants inoculated by Trichoderma prior to subsequent pathogen inoculation (Ahmed etal., 2000; Howell etal., 2000; Koike etal., 2001; Yedidia etal., 2003).