UDP-glucose pyrophosphorylase: Isolation, purification and characterization from developing thermotolerant wheat (Triticum aestivum) grains.
Protein Expr Purif
; 148: 68-77, 2018 08.
Article
en En
| MEDLINE
| ID: mdl-29654825
ABSTRACT
UDP-glucose pyrophosphorylase (UGPase, EC 2.7.7.9) activity was determined in four different thermotolerant varieties of wheat viz. WH-1021, PBW-373, Raj-3765 and DBW-16. The specific activity of UGPase was found to be highest at 21 days after anthesis (DAA) in the variety WH-1021 which has been developed by Haryana Agricultural University, Hisar (Haryana, India). Hence, crude extract prepared from immature grains (21 days after anthesis) of WH-1021 was used for purification of UGPase using standard protein purification techniques which exploit differences in protein properties viz. ammonium sulphate fractionation (based on solubility differences), DEAE-ion exchange chromatography (based on charge differences) and molecular sieving through Sephadex G-100 gel (based on molecular mass differences). Near homogeneous enzyme preparation with molecular mass of 82â¯kDa and subunit molecular weight of 39â¯kDa was obtained. The purified enzyme had thermostability upto 50⯰C. Kinetic studies revealed that the enzyme followed Michaelis Menten kinetics with Km value of 0.9â¯mM and 1.66â¯mM for UDP and PPi, respectively. Physico-chemical and kinetic characterization suggested that the enzyme UGPase from WH-1021 is a homodimer which has adapted to high temperature stress and that lower availability of substrates and high Km values may be responsible for reduced starch synthesis/grain yield.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Triticum
/
Grano Comestible
/
UTP-Glucosa-1-Fosfato Uridililtransferasa
Idioma:
En
Revista:
Protein Expr Purif
Asunto de la revista:
BIOLOGIA MOLECULAR
Año:
2018
Tipo del documento:
Article
País de afiliación:
India