Despojada de su atadura originaria al cuerpo y a la voz, la palabra persona designa, en general, diversas formas de representación (ética, legal, gramatical, religiosa, filosófica) de los individuos ...de la especie humana. Tu quebrantada fe ¿dó la pusiste? ¿Quál es el cuello que como en cadena de tus hermosos braços añudaste? (w. 127-32; 124)8 En principio, el personaje que profiere esta queja tiene un nombre, Salido, y una ocupación, pastor, que le han sido asignados en el marco introductorio del poema.9 La voz que enmarca el canto de Salido y Nemoroso estipula desde el comienzo identidades singulares y un espacio material-el lugar ameno-que les sirve de contexto. El origen de la voz en la pura materialidad del cuerpo es una de las bases de la meditación de Giorgio Agamben sobre la tensión no resuelta entre sonido (animal) y sentido (humano) que, según él, constituye a la poesía como tal: la poesía es "la Voz" que ya no es puro sonido físico, corporal, pero que no es todavía sentido acabado, sino puro designio e intención de significar (Language 35-52). "The Mental Context of Poetry: From Philosophical Concepts of Self to a Model of Poetic Consciousness (Ethos-Mode-Voice)'.'
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.
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•C. cubensis stands out as a potential producer of multi-copper oxidases.•In silico analysis shows its ability to produce 13 MCOs belonging to 5 subfamilies.•C. cubensis grown on wheat bran and orange peel induces the production of 2 MCOs.•The mco2/mco5 mixture has a positive effect on the detoxify phenolic compounds.•The mco2/mco5 mixture promoted an increase in sugarcane bagasse saccharification.
Enzymes from phytopathogenic fungi are desirable for biotechnological applications and a highly virulent phytopathogen shows great appeal for enzymes production. To assess the biotechnological ...potential of
Kretzschmaria zonata
, a plant pathogenic fungus, we analyzed its enzymatic profile after growth on six different types of lignocellulosic biomasses. The fungus was able to produce a wide variety of enzymes with superior xylanase activity. The corn cob induced the highest specific activity of xylanase, 56.30 U/mg of protein, as well as other important enzymatic activities such as endoglucanase, 11.20 U/mg of protein; pectinase, 4.52 U/mg of protein; and β-glucosidase, 2.77 U/mg of protein. The highest release of xylose, 0.88 g/L, was observed after saccharification of 10% of alkaline pretreated sugarcane bagasse by a commercial cocktail supplemented with the crude extract from
K. zonata
after growth on corn cob. The fungus extract is rich in hemicellulases and accessory enzymes and the result showed synergism between the enzymes present in the commercial mixture and in the
K. zonata
extract. This is the first report concerning the biotechnological potential of the fungus
K. zonata
, especially regarding to its ability to produce plant biomass degrading enzymes related to second generation ethanol production.
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.
•Langmuir isotherm showed higher adsorption affinity by alkali-pretreated bagasse.•Alkali-treated bagasse showed higher hydrolysis yields during recycling treatment.•Fresh substrate addition after hydrolysis cycles allowed C. cubensis enzymes recovery.
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