Biochemical characterization and low-resolution SAXS shape of a novel GH11 exo-1,4-beta-xylanase identified in a microbial consortium

Author(s)

Evangelista, Danilo Elton ^[1] ; Arnoldi Pellegrin, Vanessa de Oliveira ^[1] ; Santo, Melissa Espirito ^[1] ; McQueen-Mason, Simon ^[2] ; Bruce, Neil C. ^[2] ; Polikarpov, Igor ^[1]

Affiliation

^[1] Univ Sao Paulo, Inst Fis Sao Carlos, Ave Trabalhador Sao Carlense 400, BR-13566590 Sao Carlos, SP - Brazil

^[2] Univ York, Dept Biol, Wentworth Way, York YO10 5DD, N Yorkshire - England

• Document type: Journal article
• Source: Applied Microbiology and Biotechnology; v. 103, n. 19, p. 8035-8049, OCT 2019.
• Web of Science Citations: 0

Abstract

Biotechnologies that aim to produce renewable fuels, chemicals, and bioproducts from residual ligno(hemi)cellulosic biomass mostly rely on enzymatic depolymerization of plant cell walls (PCW). This process requires an arsenal of diverse enzymes, including xylanases, which synergistically act on the hemicellulose, reducing the long and complex xylan chains to oligomers and simple sugars. Thus, xylanases play a crucial role in PCW depolymerization. Until recently, the largest xylanase family, glycoside hydrolase family 11 (GH11) has been exclusively represented by endo-catalytic beta-1,4- and beta-1,3-xylanases. Analysis of a metatranscriptome library from a microbial lignocellulose community resulted in the identification of an unusual exo-acting GH11 beta-1,4-xylanase (MetXyn11). Detailed characterization has been performed on recombinant MetXyn11 including determination of its low-resolution small-angle X-ray scattering (SAXS) molecular envelope in solution. Our results reveal that MetXyn11 is a monomeric globular enzyme that liberates xylobiose from heteroxylans as the only product. MetXyn11 has an optimal activity in a pH range from 6 to 9 and an optimal temperature of 50 degrees C. The enzyme maintained above 65% of its original activity in the pH range 5 to 6 after being incubated for 72 h at 50 degrees C. Addition of the enzyme to a commercial enzymatic cocktail (CelicCtec3) promoted a significant increase of enzymatic hydrolysis yields of hydrothermally pretreated sugarcane bagasse (16% after 24 h of hydrolysis). (AU)

• FAPESP's process: 15/13684-0 - Structural and functional studies of enzymes that participate in complex carbohydrates synthesis and degradation
• Grantee: Igor Polikarpov
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 11/21608-1 - Identification and characterization of new enzymes with potential for lignocellulosic biomass conversion
• Grantee: Bruno Luan Soares Paula de Mello
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• FAPESP's process: 10/52362-5 - Targeted analysis of microbial lignocellulolytic secretomes: a new approach to enzyme discovery
• Grantee: Igor Polikarpov
• Support Opportunities: Regular Research Grants
• FAPESP's process: 11/20505-4 - Two important classes of glycosyl hydrolases: functional studies and structural analysis
• Grantee: Marco Antonio Seiki Kadowaki
• Support Opportunities: Scholarships in Brazil - Post-Doctoral