Targeted metatranscriptomics of compost-derived consortia reveals a GH11 exerting an unusual exo-1,4-beta-xylanase activity

Author(s)

Mello, Bruno L. ^[1] ; Alessi, Anna M. ^[2] ; Riano-Pachon, Diego M. ^{[3, 4]} ; deAzevedo, Eduardo R. ^[1] ; Guimaraes, Francisco E. G. ^[1] ; Espirito Santo, Melissa C. ^[1] ; McQueen-Mason, Simon ^[2] ; Bruce, Neil C. ^[2] ; Polikarpov, Igor ^[1]

Affiliation

^[1] Univ Sao Paulo, Inst Fis Sao Carlos, Av Trabalhador Sao Carlense 400, BR-13560970 Sao Carlos, SP - Brazil

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

^[3] Ctr Nacl Pesquisa Energia & Mat, Lab Nacl Ciencia Tecnol & Bioetanol, Rua Giuseppe Maximo Scalfaro 10000, BR-13083100 Campinas, SP - Brazil

^[4] Univ Sao Paulo, Inst Quim, Dept Quim, Lab Biol Sistemas Regulatorios, Av Prof Lineu Prestes 748, BR-05508000 Sao Paulo, SP - Brazil

• Document type: Journal article
• Source: BIOTECHNOLOGY FOR BIOFUELS; v. 10, NOV 2 2017.
• Web of Science Citations: 7

Abstract

Background: Using globally abundant crop residues as a carbon source for energy generation and renewable chemicals production stand out as a promising solution to reduce current dependency on fossil fuels. In nature, such as in compost habitats, microbial communities efficiently degrade the available plant biomass using a diverse set of synergistic enzymes. However, deconstruction of lignocellulose remains a challenge for industry due to recalcitrant nature of the substrate and the inefficiency of the enzyme systems available, making the economic production of lignocellulosic biofuels difficult. Metatranscriptomic studies of microbial communities can unveil the metabolic functions employed by lignocellulolytic consortia and identify novel biocatalysts that could improve industrial lignocellulose conversion. Results: In this study, a microbial community from compost was grown in minimal medium with sugarcane bagasse sugarcane bagasse as the sole carbon source. Solid-state nuclear magnetic resonance was used to monitor lignocellulose degradation; analysis of metatranscriptomic data led to the selection and functional characterization of several target genes, revealing the first glycoside hydrolase from Carbohydrate Active Enzyme family 11 with exo-1,4-beta-xylanase activity. The xylanase crystal structure was resolved at 1.76 angstrom revealing the structural basis of exo-xylanase activity. Supplementation of a commercial cellulolytic enzyme cocktail with the xylanase showed improvement in Avicel hydrolysis in the presence of inhibitory xylooligomers. Conclusions: This study demonstrated that composting microbiomes continue to be an excellent source of biotechnologically important enzymes by unveiling the diversity of enzymes involved in in situ lignocellulose degradation. (AU)

• 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: 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