Active site histidine in spinach ribulosebisphosphate carboxylase/oxygenase modified by diethyl pyrocarbonate

Journal Article · Tue Jul 16 00:00:00 EDT 1985 · Biochemistry; (United States)

DOI:https://doi.org/10.1021/bi00336a024· OSTI ID:6259022

Igarashi, Y; McFadden, B A; el-Gul, T

(TH) Diethyl pyrocarbonate was synthesized from (TH) ethanol prepared by the reduction of acetaldehyde by NaB3H4. Ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) from spinach was inactivated with this reagent at pH 7.0 the presence of 20 mM MgS , and tryptic peptides that contained modified histidine residues were isolated by reverse-phase high-performance liquid chromatography. Labeling of the enzyme was conducted in the presence and absence of the competitive inhibitor sedoheptulose 1,7-bisphosphate. The amount of one peptide that was heavily labeled in the absence of this compound was reduced 10-fold in its presence. The labeled residue was histidine-298. This result, in combination with earlier experiments, suggests that His-298 in spinach RuBisCO is located in the active site domain and is essential to enzyme activity. This region of the primary structure is strongly conserved in seven other ribulosebisphosphate carboxylases from divergent sources.

• Research Organization: Washington State Univ., Pullman
• OSTI ID: 6259022
• Journal Information: Biochemistry; (United States), Vol. 15
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
CARBONATES
BIOSYNTHESIS
CARBOXYLASE
KINETICS
TRITIUM COMPOUNDS
AMINO ACID SEQUENCE
HISTIDINE
SPINACH
TRYPSIN
AMINO ACIDS
AZOLES
CARBON COMPOUNDS
CARBON-CARBON LYASES
CARBOXY-LYASES
CARBOXYLIC ACIDS
ENZYMES
FOOD
HETEROCYCLIC ACIDS
HETEROCYCLIC COMPOUNDS
HYDROLASES
IMIDAZOLES
LABELLED COMPOUNDS
LYASES
MOLECULAR STRUCTURE
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OXYGEN COMPOUNDS
PEPTIDE HYDROLASES
PLANTS
SERINE PROTEINASES
SYNTHESIS
VEGETABLES
550201* - Biochemistry- Tracer Techniques