Three novel rhamnogalacturonan I- pectins degrading enzymes from Aspergillus aculeatinus: Biochemical characterization and application potential.
Carbohydr Polym
; 248: 116752, 2020 Nov 15.
Article
in En
| MEDLINE
| ID: mdl-32919555
ABSTRACT
Rhamnogalaturonans I (RGI) pectins, which are a major component of the plant primary cell wall, can be recalcitrant to digestion by commercial enzymatic cocktails, in particular during fruit juice clarification process. To overcome these problems and get better insights into RGI degradation, three RGI degrading enzymes (RHG Endo-rhamnogalacturonase; ABF α-Arabinofuranosidases; GAN Endo-ß-1,4-galactanase) from Aspergillus aculeatinus were expressed in Pichia pastoris, purified and fully biochemically characterized. All three enzymes showed acidic pH optimum, and temperature optima between 40-50 °C. The Km values were 0.5 mg.ml-1, 1.64 mg.ml-1 and 3.72 mg.ml-1 for RHG, ABF, GAN, respectively. NMR analysis confirmed an endo-acting mode of action for RHG and GAN, and exo-acting mode for ABF. The application potential of these enzymes was assessed by measuring changes in viscosity of RGI-rich camelina mucilage, showing that RHG-GAN enzymes induced a decrease in viscosity by altering the structures of the RGI backbone and sidechains.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Aspergillus
/
Fungal Proteins
/
Pectins
Language:
En
Journal:
Carbohydr Polym
Year:
2020
Document type:
Article
Affiliation country:
France
Publication country:
ENGLAND
/
ESCOCIA
/
GB
/
GREAT BRITAIN
/
INGLATERRA
/
REINO UNIDO
/
SCOTLAND
/
UK
/
UNITED KINGDOM