PMID: 6988217Mar 1, 1980Paper

Flavocytochrome b2 (Baker's yeast). Deuterium isotope effect studied by rapid-kinetic methods as a probe for the mechanism of electron transfer

European Journal of Biochemistry
D PomponF Lederer


The use of DL-[2-2H]lactate in steady-state measurements of ferricyanide reduction by flavocytochrome b2 at 30 degrees C has previously yielded an isotope effect of 5 [F. Lederer (1974) Eur. J. Biochem. 46, 393--399]. We report here studies carried out at 5 degrees C with L-[2-2H]lactate, where flavin and heme reduction were observed in the stopped-flow apparatus, in the absence of acceptor. The generally biphasic reduction curves were analysed according to a new mathematical treatment which allowed us to derive microscopic constants from initial reduction rates. It has thus been possible to determine an isotope effect of 8 on flavin reduction, 6 on heme reduction, compared to 4 in the steady state. Consequently, two slightly rate-limiting steps occur after the first one where the alpha-hydrogen is abstracted. It has also been possible to calculate the substrate association and dissociation rate constants for intact enzyme. The studies were carried out in parallel on intact and cleaved cytochrome b2. The results suggest that proteolysis affects essentially the steps involved in flavin reduction, and not intramolecular electron transfer steps. Moreover, the experimental data obtained at low rates of electron entry have led us to...Continue Reading


Sep 15, 1973·Biochimica Et Biophysica Acta·K YagiN Oishi
Jan 31, 1972·European Journal of Biochemistry·C Jacq, F Lederer
Jan 16, 1974·European Journal of Biochemistry·C Jacq, F Lederer
Jul 23, 1969·Biochemical and Biophysical Research Communications·D J Porter, H J Bright
Mar 1, 1959·The Biochemical Journal·C A APPLEBY, R K MORTON


Jan 1, 1994·Protein Science : a Publication of the Protein Society·A Balme, F Lederer
Feb 1, 1994·Protein Science : a Publication of the Protein Society·M Tegoni, C Cambillau
Jul 31, 1998·Protein Science : a Publication of the Protein Society·K S Rao, F Lederer
Jul 15, 1984·Experientia·J L Dreyer
Jan 1, 1994·Biochimie·F Lederer
May 3, 2001·Journal of Photochemistry and Photobiology. B, Biology·D BhattacharyaP C Mandal
Mar 27, 1999·Journal of Photochemistry and Photobiology. B, Biology·D BhattacharyaP C Mandal
May 1, 1987·Proceedings of the National Academy of Sciences of the United States of America·Z X XiaF S Mathews
Nov 1, 1981·European Journal of Biochemistry·R Ghrir, F Lederer
Aug 1, 1983·European Journal of Biochemistry·P UrbanF Lederer
Oct 15, 1984·European Journal of Biochemistry·P Urban, F Lederer
Dec 15, 1988·European Journal of Biochemistry·G A ReidS K Chapman
Apr 1, 1992·Protein Science : a Publication of the Protein Society·F Lederer
May 26, 2016·Physical Chemistry Chemical Physics : PCCP·N GilletV Moliner
Jul 3, 1995·Biochimica Et Biophysica Acta·D BhattacharyaP C Mandal

Related Concepts

Respiratory Chain
Isotope Labeling, Stable
Lactate Dehydrogenase
Saccharomyces cerevisiae
L-Lactate dehydrogenase (cytochrome)

Trending Feeds


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.

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.

Lipidomics & Rhinovirus Infection

Lipidomics can be used to examine the lipid species involved with pathogenic conditions, such as viral associated inflammation. Discovered the latest research on Lipidomics & Rhinovirus Infection.

Spatio-Temporal Regulation of DNA Repair

DNA repair is a complex process regulated by several different classes of enzymes, including ligases, endonucleases, and polymerases. This feed focuses on the spatial and temporal regulation that accompanies DNA damage signaling and repair enzymes and processes.

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.

Torsion Dystonia

Torsion dystonia is a movement disorder characterized by loss of control of voluntary movements appearing as sustained muscle contractions and/or abnormal postures. Here is the latest research.

Archaeal RNA Polymerase

Archaeal RNA polymerases are most similar to eukaryotic RNA polymerase II but require the support of only two archaeal general transcription factors, TBP (TATA-box binding protein) and TFB (archaeal homologue of the eukaryotic general transcription factor TFIIB) to initiate basal transcription. Here is the latest research on archaeal RNA polymerases.

Alzheimer's Disease: MS4A

Variants within the membrane-spanning 4-domains subfamily A (MS4A) gene cluster have recently been implicated in Alzheimer's disease in genome-wide association studies. Here is the latest research on Alzheimer's disease and MS4A.

Central Pontine Myelinolysis

Central Pontine Myelinolysis is a neurologic disorder caused most frequently by rapid correction of hyponatremia and is characterized by demyelination that affects the central portion of the base of the pons. Here is the latest research on this disease.