title: Molecular and biochemical characterization of dehydroascorbate reductase from a stress adapted C4 plant, pearl millet [Pennisetum glaucum (L.) R. Br].
abstract: CONCLUSIONS
  PgDHAR was isolated from Pennisetum glaucum. PgDHAR responded to abiotic stress and exhibited enzyme activity at broad ranges of temperature, pH and substrate concentrations suggesting its role in stress tolerance.
  Dehydroascorbate reductase (EC 1.8.5.1) is a crucial enzyme actively involved in the recycling of ascorbate redox pool in the cellular environment. In this study, the full-length cDNA coding for DHAR polypeptide and its corresponding gene was isolated from Pennisetum glaucum (PgDHAR). PgDHAR encodes a polypeptide of 213 amino acids with a predicted molecular mass of 23.4 kDa and shares 80-75 % sequence homology with DHAR from other plants. The heterologously expressed recombinant PgDHAR protein exhibited activity in a wide range of substrate concentrations. The recombinant PgDHAR is thermostable and retains its activity over a broad pH range. Furthermore, transcript level of PgDHAR is quantitatively up-regulated in response to temperature. On the whole, PgDHAR alone or in combination with other genes of ascorbate-glutathione cycle can be used for the development of stress tolerant as well as nutritionally improved food crop with enhanced ascorbic acid content.
authors: Plant Molecular Biology Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, 110 067, India, prachipndy@gmail.com.
authors: Prachi
authors: P
authors: Pandey
authors: V Mohan Murali
authors: VM
authors: Achary
authors: Vani
authors: V
authors: Kalasamudramu
authors: Srikrishna
authors: S
authors: Mahanty
authors: Guda Maheedhara
authors: GM
authors: Reddy
authors: Malireddy K
authors: MK
authors: Reddy
mesh_terms: D018506:Gene Expression Regulation, Plant; D006863:Hydrogen-Ion Concentration; D010088:Oxidoreductases / Q000235:genetics / Q000378:metabolism*; D031782:Pennisetum / Q000201:enzymology* / Q000235:genetics; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D060888:Real-Time Polymerase Chain Reaction; D013696:Temperature
chemical_list: D010940:Plant Proteins; D010088:Oxidoreductases; C020666:glutathione dehydrogenase (ascorbate)