Cysteine‐153 is required for redox regulation of pea chloroplast fructose‐1,6‐bisphosphatase

FEBS Letters

Miginiac-Maslow, Myroslawa²  Lopez-Jaramillo, Javier³  Chueca, Ana³  Lemaire, Stéphane²  Cherfils, Jacqueline¹  Lopez-Gorge, Julio³  Jacquot, Jean-Pierre² 

[1] Laboratoire d'Enzymologie, CNRS 91190 Gif/Yvette, France;Institut de Biotechnologie des Plantes, URA 1128 CNRS, Université de Paris-Sud, Batiment 630, 91405 Orsay Cedex, France;CSIC Estacion Experimental del Zaidin Profesor Albareda 1, 18008 Granada, Spain

关键词: Chloroplast;    Fructose-1;    6-bisphosphatase;    Redox regulation;    FBPase;    fructose-1;    6-bisphosphatase;    DTT;    dithiothreitol;    NTR;    NADPH thioredoxin reductase;   

DOI  :  10.1016/S0014-5793(96)01459-7

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Chloroplastic fructose-1,6-bisphosphatases are redox regulatory enzymes which are activated by the ferredoxin thioredoxin system via the reduction/isomerization of a critical disulfide bridge. All chloroplastic sequences contain seven cysteine residues, four of which are located in, or close to, an amino acid insertion region of approximately 17 amino acids. In order to gain more information on the nature of the regulatory site, five cysteine residues (Cys⁴⁹, Cys¹⁵³, Cys¹⁷³, Cys¹⁷⁸ and Cys¹⁹⁰) have been modified individually into serine residues by site-directed mutagenesis. While mutations C173S and C178S strongly affected the redox regulatory properties of the enzyme, the most striking effect was observed with the C153S mutant which became permanently active and redox independent. On the other hand, the C190S mutant retained most of the properties of the wild-type enzyme (except that it could now also be partially activated by the NADPH/NTR/thioredoxin h system). Finally, the C49S mutant is essentially identical to the wild-type enzyme. These results are discussed in the light of recent crystallographic data obtained on spinach FBPase [Villeret et al. (1995) Biochemistry 34, 4299–4306].

【 授权许可】

Unknown