Heterologous production and biochemical characterization of a new highly glucose tolerant GH1 beta-glucosidase from Anoxybacillus thermarum

Autor(es)

de Almeida, Paula Zaghetto ^[1] ; de Oliveira, Tassio Brito ^[2] ; de Lucas, Rosymar Coutinho ^{[1, 2]} ; Santos Salgado, Jose Carlos ^[3] ; Perez, Malena Martinez ^[1] ; Galan, Beatriz ^[4] ; Garcia, Jose Luis ^[4] ; Teixeira de Moraes Polizeli, Maria de Lourdes ^{[1, 2]}

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Fac Med Ribeirao Preto, Dept Bioquim & Imunol, Ribeirao Preto, SP - Brazil

^[2] Univ Sao Paulo, Fac Filosofia Ciencias & Letras Ribeirao Preto, Dept Biol, Bandeirantes Av 3900, BR-14040901 Ribeirao Preto, SP - Brazil

^[3] Univ Sao Paulo, Fac Filosofia Ciencias & Letras Ribeirao Preto, Dept Quim, Ribeirao Preto, SP - Brazil

^[4] Ctr Invest Biol CSIC, Dept Microbial & Plant Biotechnol, Environm Biotechnol Lab, Calle Ramiro Maetzu 9, Ciudad Univ, Madrid - Spain

• Tipo de documento: Artigo Científico
• Fonte: Process Biochemistry; v. 99, p. 1-8, DEC 2020.
• Citações Web of Science: 0

Resumo

The enzymatic lignocellulosic biomass conversion into value-added products requires the use of enzyme-rich cocktails, including beta-glucosidases that hydrolyze cellobiose and cellooligosaccharides to glucose. During hydrolysis occurs accumulation of monomers causing inhibition of some enzymes; thus, glucose/xylose tolerant beta-glucosidases could overcome this drawback. The search of new tolerant enzymes showing additional properties, such as high activity, wide-pH range, and thermal stability is very relevant to improve the bioprocess. We describe a novel beta-glucosidase GH1 from the thermophilic Anoxybacillus thermarum (BgAt), which stood out by the robustness combination of great glucose/xylose tolerance, thermal stability, and high Vmax. The recombinant his-tagged-BgAt was overexpressed in Escherichia coli, was purified in one step, showed a high glucose/xylose tolerance, and activity stimulation (presence of 0.4 M glucose/1.0 M xylose). The optimal activity was at 65 degrees C - pH 7.0. BgAt presented an extraordinary temperature stability (48 h - 50 degrees C), and pH stability (5.5-8.0). The novel enzyme showed outstanding Vmax values compared to other beta-glucosidases. Using p-nitrophenyl-beta-D-glucopyranoside as substrate the values were Vmax (7614 U/mg), and KM (0.360 mM). These values suffer a displacement in Vmax to 14,026 U/mg (glucose), 14,886 U/mg (xylose), and KM 0.877 mM (glucose), and 1.410 mM (xylose). (AU)

• Processo FAPESP: 18/07522-6 - Desenvolvimento de tecnologias ecológicas para a hidrólise de biomassa e resíduos da indústria de celulose e papel
• Beneficiário: Maria de Lourdes Teixeira de Moraes Polizeli
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 17/09000-4 - Efeitos da temperatura e da deficiência hídrica, em cenário climático futuro, na comunidade de fungos em solo tropical e na seleção de linhagens produtoras de óxido nitroso
• Beneficiário: Tássio Brito de Oliveira
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 14/50884-5 - INCT 2014: Instituto Nacional de Ciência e Tecnologia do Bioetanol
• Beneficiário: Marcos Silveira Buckeridge
• Modalidade de apoio: Auxílio à Pesquisa - Temático