The mechanism by which a distinguishing arabinofuranosidase can cope with internal di-substitutions in arabinoxylans

Autor(es):Mostrar menos -

dos Santos, Camila Ramos ^[1] ; de Giuseppe, Priscila Oliveira ^[1] ; Moreira de Souza, Flavio Henrique ^[1] ; Zanphorlin, Leticia Maria ^[1] ; Domingues, Mariane Noronha ^[1] ; Siqueira Pirolla, Renan Augusto ^[1] ; Honorato, Rodrigo Vargas ^[2] ; Costa Tonoli, Celisa Caldana ^[2] ; Bueno de Morais, Mariana Abrahao ^[1] ; de Matos Martins, Vanesa Peixoto ^[2] ; Fonseca, Lucas Miranda ^[1] ; Buchli, Fernanda ^[1] ; Lopes de Oliveira, Paulo Sergio ^[2] ; Gozzo, Fabio Cesar ^[3] ; Murakami, Mario Tyago ^[1]

Afiliação do(s) autor(es)

^[1] Brazilian Ctr Res Energy & Mat CNPEM, Brazilian Bioethanol Sci & Technol Lab CTBE, BR-13083970 Campinas, SP - Brazil

^[2] Brazilian Ctr Res Energy & Mat CNPEM, Brazilian Biosci Natl Lab LNBio, BR-13083970 Campinas, SP - Brazil

^[3] Univ Estadual Campinas, Inst Chem, Dalton Mass Spectrometry Lab, BR-13083861 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: BIOTECHNOLOGY FOR BIOFUELS; v. 11, AUG 11 2018.
• Citações Web of Science: 2

Resumo

Background: Arabinoxylan is an abundant polysaccharide in industrially relevant biomasses such as sugarcane, corn stover and grasses. However, the arabinofuranosyl di-substitutions that decorate the xylan backbone are recalcitrant to most known arabinofuranosidases (Abfs). Results: In this work, we identified a novel GH51 Abf (XacAbf51) that forms trimers in solution and can cope efficiently with both mono- and di-substitutions at terminal or internal xylopyranosyl units of arabinoxylan. Using mass spectrometry, the kinetic parameters of the hydrolysis of 3(3)-alpha-L-arabinofuranosyl-xylotetraose and 2(3),3(3)-di-alpha-L-arabinofuranosyl-xylotetraose by XacAbf51 were determined, demonstrating the capacity of this enzyme to cleave arabinofuranosyl linkages of internal mono- and di-substituted xylopyranosyl units. Complementation studies of fungal enzyme cocktails with XacAbf51 revealed an increase of up to 20% in the release of reducing sugars from pretreated sugarcane bagasse, showing the biotechnological potential of a generalist GH51 in biomass saccharification. To elucidate the structural basis for the recognition of internal di-substitutions, the crystal structure of XacAbf51 was determined unveiling the existence of a pocket strategically arranged near to the - 1 subsite that can accommodate a second arabinofuranosyl decoration, a feature not described for any other GH51 Abf structurally characterized so far. Conclusions: In summary, this study reports the first kinetic characterization of internal di-substitution release by a GH51 Abf, provides the structural basis for this activity and reveals a promising candidate for industrial processes involving plant cell wall depolymerization. (AU)

• Processo FAPESP: 13/13309-0 - Estudos do comportamento funcional e estrutural de enzimas evolutivamente especializadas na degradação de biomassa vegetal com potenciais aplicações biotecnológicas
• Beneficiário: Mário Tyago Murakami
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 14/17264-3 - Novas fronteiras em proteômica estrutural: caracterizando estruturas de proteínas e complexos proteicos por espectrometria de massas
• Beneficiário: Fabio Cesar Gozzo
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 15/26982-0 - Explorando novas estratégias para a despolimerização de polissacarídeos da parede celular vegetal: da estrutura, função e desenho racional de hidrolases glicosídicas às implicações biológicas e potenciais aplicações biotecnológicas
• Beneficiário: Mário Tyago Murakami
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 14/07135-1 - EMU concedido no processo 2013/13309-0 - aquisição do sistema de eletroforese capilar com detector de fluorescência - Beckman Coulter
• Beneficiário: Mário Tyago Murakami
• Modalidade de apoio: Auxílio à Pesquisa - Programa Equipamentos Multiusuários