Pyridoxal phosphate as a probe in the active site of ribulose bisphosphate carboxylase/oxygenase

Archives of Biochemistry and Biophysics
A S Bhagwat, B A McFadden

Abstract

Ribulose bisphosphate (RuBP) carboxylase is rapidly and irreversibly inactivated by photooxidation sensitized by pyridoxal phosphate. Both pyridoxal and pyridoxamine phosphate were much less effective in sensitizing the photooxidation even when used at twice the concentration of pyridoxal phosphate. These results imply that pyridoxal phosphate binds at the active site not only through a Schiff base, but also through ionic interaction with the phosphate binding region. Spectral analysis of the photooxidized enzyme showed a new absorption maximum at 325 nm due to reduction of the Schiff base between pyridoxal phosphate and a lysyl residue with concomitant oxidation of a histidine residue. The stoichiometry of photooxidative [3H]pyridoxal phosphate incorporation was 0.87 mol/mol of a 70,000-dalton large subunit-small subunit combination. Studies with 3H-labeled diethyl pyrocarbonate showed that both photooxidation and carbethoxylation occur at the same histidine residue. However, photooxidation by pyridoxal phosphate is very specific for an active site histidine residue due to the high specificity of this affinity label. Several competitive inhibitors with respect to ribulose bisphosphate offered appreciable protection against pyr...Continue Reading

References

May 14, 1979·Biochemical and Biophysical Research Communications·P D Robison, F R Tabita
Feb 14, 1978·Biochemical and Biophysical Research Communications·V B Lawlis, B A McFadden
Aug 23, 1976·Biochemical and Biophysical Research Communications·W Whitman, F R Tabita
Nov 10, 1970·Biochemistry·T Sugiyama, T Akazawa
Apr 1, 1983·Archives of Biochemistry and Biophysics·D J RoachB A McFadden
Jun 1, 1983·Archives of Biochemistry and Biophysics·A S Bhagwat, B A McFadden
Jun 30, 1980·Biochemical and Biophysical Research Communications·A K Saluja, B A McFadden
May 1, 1959·Archives of Biochemistry and Biophysics·G L ELLMAN
Dec 28, 1964·Annals of the New York Academy of Sciences·B J DAVIS

❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.