Photomodification of a serine at the active site of ribulose-1,5-bisphosphate carboxylase/oxygenase by vanadate
- Washington State Univ., Pullman (USA)
Irradiation of ribulose-1,5-bisphosphate carboxylase/oxygenase from spinach in the presence of vanadate at 4 degrees C resulted in rapid loss of carboxylase activity. The inactivation was light and vanadate dependent. When the enzyme was irradiated in the presence of the substrate ribulose 1,5-bisphosphate or an analogue such as fructose 1,6-bisphosphate, the inactivation was greatly reduced. Sodium bicarbonate and phosphate also protected against inactivation. No additional protection was observed in the presence of Mg{sup 2+} nor did Mg{sup 2+} alone protect. Carboxylase activity could be partially restored by treatment with NaBH4, and the photomodified protein could be tritiated with NaB3H4. Amino acid analysis showed that the tritium had been incorporated into serine. The data suggest that an active-site serine is photooxidized by vanadate to an aldehyde which results in activity loss. Irradiation in the presence of vanadate also resulted in cleavage in the large subunit of the enzyme which was subsequent to inactivation.
- OSTI ID:
- 5259043
- Journal Information:
- Biochemistry; (USA), Journal Name: Biochemistry; (USA) Vol. 28:13; ISSN 0006-2960; ISSN BICHA
- Country of Publication:
- United States
- Language:
- English
Similar Records
Identification of the large subunit of Ribulose 1,5-bisphosphate carboxylase/oxygenase as a substrate for transglutaminase in Medicageo sativa L. (alfalfa)
2-(4-bromoacetamido)anilino-2-deoxypentitol 1,5-bisphosphate, a new affinity label for ribulose bisphosphate carboxylase/oxygenase from Rhodospirillum rubrum: determination of reaction parameters and characterization of an active site peptide
Related Subjects
Cells
& Tissue Culture
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ALKALI METAL COMPOUNDS
AMINO ACID SEQUENCE
AMINO ACIDS
BOROHYDRIDES
BORON COMPOUNDS
CARBON COMPOUNDS
CARBON-CARBON LYASES
CARBONATES
CARBOXY-LYASES
CARBOXYLIC ACIDS
CHEMICAL RADIATION EFFECTS
CHEMISTRY
ELECTROMAGNETIC RADIATION
ELEMENTS
ENZYME ACTIVITY
ENZYME REACTIVATION
ENZYMES
HYDROGEN COMPOUNDS
HYDROXY ACIDS
LYASES
METALS
MOLECULAR STRUCTURE
ORGANIC ACIDS
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
PHOSPHATES
PHOSPHORUS COMPOUNDS
RADIATION CHEMISTRY
RADIATION EFFECTS
RADIATIONS
RADIOSENSITIVITY EFFECTS
RIBULOSE DIPHOSPHATE CARBOXYLASE
SERINE
SODIUM CARBONATES
SODIUM COMPOUNDS
TRANSITION ELEMENTS
ULTRAVIOLET RADIATION
VANADIUM