Influence of Different Lignocellulose Sources on Endo-1,4-β-Glucanase Gene Expression and Enzymatic Activity of Bacillus amyloliquefaciens B31C

• Main Authors: Rosangela Di Pasqua, Valeria Ventorino, Alberto Aliberti, Alessandro Robertiello, Vincenza Faraco, Sharon Viscardi, Olimpia Pepe
• Format: Article
• Language: English
• Published: North Carolina State University 2014-01-01
• Series: BioResources
• Subjects: Bioethanol; Bacillus amyloliquefaciens; endo-1; 4-β-glucanase; Arundo donax biomass; qRT-PCR; bglC gene
• Online Access: http://ojs.cnr.ncsu.edu/index.php/BioRes/article/view/BioRes_09_1_1303_DiPasqua_Gene_Expression_Bacillus

Conversion of cellulose into fermentable sugars for ethanol production is currently performed by enzymatic hydrolysis catalyzed by cellulases. The cellulases are produced by a wide variety of microorganisms, playing a major role in the recycling of biomass. The endo-1,4-β-glucanase (CelB31C) from Bacillus amyloliquefaciens B31C, isolated from compost and previously selected on the basis of highest cellulase activity levels among Bacillus isolated, was characterized as being a potential candidate for a biocatalyst in lignocellulose conversion for second-generation bioethanol production. The aim of this work was to evaluate the changes in production of enzymatic activity of the endo-1,4-β-glucanase (CelB31C) and the expression of its gene (bglC) using a carboxymethylcellulase activity assay and qRT-PCR analysis, respectively, during growth of B. amyloliquefaciens B31C on different cellulose sources: carboxymethylcellulose (CMC), pure cellulose from Arundo donax, pretreated Arundo donax biomass (Chemtex), and microcrystalline cellulose (Avicel). The results showed that both the expression of bglC gene and the enzymatic activity production are related to the type of cellulose source. The strain showed a high enzymatic activity on lignocellulosic biomass and on microcrystalline cellulose. Furthermore, the highest gene expression occurred during the exponential phase of growth, except in the presence of Avicel.