Beta glucosidase from Bacillus polymyxa is activated by glucose-6-phosphate.
Arch Biochem Biophys
; 580: 50-6, 2015 Aug 15.
Article
in En
| MEDLINE
| ID: mdl-26116788
ABSTRACT
Optimization of cellulose enzymatic hydrolysis is crucial for cost effective bioethanol production from lignocellulosic biomass. Enzymes involved in cellulose hydrolysis are often inhibited by their end-products, cellobiose and glucose. Efforts have been made to produce more efficient enzyme variants that are highly tolerant to product accumulation; however, further improvements are still necessary. Based on an alternative approach we initially investigated whether recently formed glucose could be phosphorylated into glucose-6-phosphate to circumvent glucose accumulation and avoid inhibition of beta-glucosidase from Bacillus polymyxa (BGLA). The kinetic properties and structural analysis of BGLA in the presence of glucose-6-phosphate (G6P) were investigated. Kinetic studies demonstrated that enzyme was not inhibited by G6P. In contrast, the presence of G6P activated the enzyme, prevented beta glucosidase feedback inhibition by glucose accumulation and improved protein stability. G6P binding was investigated by fluorescence quenching experiments and the respective association constant indicated high affinity binding of G6P to BGLA. Data reported here are of great impact for future design strategies for second-generation bioethanol production.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Bacillus
/
Bacterial Proteins
/
Beta-Glucosidase
/
Glucose-6-Phosphate
Language:
En
Journal:
Arch Biochem Biophys
Year:
2015
Document type:
Article
Affiliation country:
Brazil
Publication country:
EEUU
/
ESTADOS UNIDOS
/
ESTADOS UNIDOS DA AMERICA
/
EUA
/
UNITED STATES
/
UNITED STATES OF AMERICA
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US
/
USA