Heterologous production and characterization of endo-mannanases from GH5 family

• Grant number: 22/08114-4
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2022
• End date: July 16, 2023
• Field of knowledge: Biological Sciences - Biochemistry - Enzymology
• Principal Investigator: Igor Polikarpov
• Grantee: Guilherme Romualdo Silva
• Host Institution: Instituto de Física de São Carlos (IFSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil

Abstract

Plant cell walls polysaccharides consist mainly of cellulose, and hemicellulose, a complex group of heterogeneous polymers and are one of the largest sources of renewable organic matter. Mannan is one of the main constituents of hemicellulose and can be classified into four groups, according to their molecular structure: linear mannans, glucomannans, galactomannans, and galactoglucomannans. Mannanases can be used both in the pre-treatment of biomass and in obtaining sugars for the production of biofuels. Endo-mannanases are enzymes capable of carrying out the hydrolysis of mannans, cleaving glycosidic bonds inside the main chain, and releasing short beta-1,4-mannooligomers. The main families that contemplate this activity are the GH5, GH26, and GH113 families. Furthermore, the degradation of mannan can generate mannan oligosaccharides (MOS), which are considered prebiotics for stimulating the growth of beneficial microorganisms for the intestinal flora, such as the Lactobacillus and Bifidobacterium genera. In this project, we are proposing to conduct the biochemical characterization of two mannanases, from the GH5 family, and evaluate their use in mannan degradation and MOS production from lignocellulosic biomass. The biochemical characteristics of the enzymes, as well as the spectra of products generated, will be compared since mannans with different properties are important for obtaining mannan oligosaccharides, which may favor the production of products with different degrees of polymerization and ramifications.(AU)