Dataset Information

Penicillium citrinum UFV1 ?-glucosidases: purification, characterization, and application for biomass saccharification.

ABSTRACT:

Background

?-Glucosidases are components of the cellulase system, a family of enzymes that hydrolyze the ?-1,4 linkages of cellulose. These proteins have been extensively studied due to the possibility of their use in various biotechnological processes. They have different affinities for substrates (depending on their source) and their activities can be used for saccharification of different types of biomass. In this context, the properties and the synergistic capacity of ?-glucosidases from different organisms, to supplement the available commercial cellulase cocktails, need a comprehensive evaluation.

Results

Two ?-glucosidases belonging to GH3 family were secreted by Penicillium citrinum UFV. Pc?Glu1 (241 kDa) and Pc?Glu2 (95 kDa) presented acidic and thermo-tolerant characteristics. Pc?Glu1 showed Michaelis-Menten kinetics for all substrates tested with K_m values ranging from 0.09?±?0.01 (laminarin) to 1.7?±?0.1 mM (cellobiose, C2) and k_cat values ranging from 0.143?±?0.005 (laminarin) to 8.0?±?0.2 s^-1 (laminaribiose, Lb). Pc?Glu2 showed substrate inhibition for 4-methylumbelliferyl-?-d-glucopyranoside (MU?Glu), p-nitrophenyl-?-d-glucopyranoside (pNP?Glu), cellodextrins (C3, C4, and C5), N-octil-?-d-glucopyranoside, and laminaribiose, with K_m values ranging from 0.014?±?0.001 (MU?Glu) to 0.64?±?0.06 mM (C2) and k_cat values ranging from 0.49?±?0.01 (gentiobiose) to 1.5?±?0.2 s^-1 (C4). Inhibition constants (K_i) for Pc?Glu2 substrate inhibition ranged from 0.69?±?0.07 (MU?Glu) to 10?±?1 mM (Lb). Glucose and cellobiose are competitive inhibitors of Pc?Glu1 and Pc?Glu2 when pNP?Glu is used as a substrate. For Pc?Glu1 inhibition, K_i?=?1.89?±?0.08 mM (glucose) and K_i?=?3.8?±?0.1 mM (cellobiose); for Pc?Glu2, K_i?=?0.83?±?0.05 mM (glucose) and K_i?=?0.95?±?0.07 mM (cellobiose). The enzymes were tested for saccharification of different biomasses, individually or supplementing a Trichoderma reesei commercial cellulose preparation. Pc?Glu2 was able to hydrolyze banana pseudostem and coconut fiber with the same efficiency as the T. reesei cocktail, showing significant synergistic properties with T. reesei enzymes in the hydrolysis of these alternative biomasses.

Conclusions

The ?-glucosidases from P. citrinum UFV1 present different enzymatic properties from each other and might have potential application in several biotechnological processes, such as hydrolysis of different types of biomass.

SUBMITTER: da Costa SG

PROVIDER: S-EPMC6100729 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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Publications

<i>Penicillium citrinum</i> UFV1 <i>β</i>-glucosidases: purification, characterization, and application for biomass saccharification.

da Costa Samara G SG Pereira Olinto Liparini OL Teixeira-Ferreira André A Valente Richard Hemmi RH de Rezende Sebastião T ST Guimarães Valéria M VM Genta Fernando Ariel FA

Biotechnology for biofuels 20180820

<h4>Background</h4><i>β</i>-Glucosidases are components of the cellulase system, a family of enzymes that hydrolyze the <i>β</i>-1,4 linkages of cellulose. These proteins have been extensively studied due to the possibility of their use in various biotechnological processes. They have different affinities for substrates (depending on their source) and their activities can be used for saccharification of different types of biomass. In this context, the properties and the synergistic capacity of < ...[more]

PMID: 30151054

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