Old Yellow enzyme: aromatization of cyclic enones and the mechanism of a novel dismutation reaction.

@article{Vaz1995OldYE,
  title={Old Yellow enzyme: aromatization of cyclic enones and the mechanism of a novel dismutation reaction.},
  author={Alfin D. N. Vaz and Sumita Chakraborty and Vincent Massey},
  journal={Biochemistry},
  year={1995},
  volume={34 13},
  pages={
          4246-56
        }
}
The origin of charge transfer bands that develop on reaction of Old Yellow Enzyme with alpha,beta-unsaturated cyclic ketones such as 3-oxodecalin-4-ene (ODE, numbered according to the convention for steroids), 3-oxodecalin-4-ene-10-carboxaldehyde (ODEC), and 2-cyclohexenone is shown to be due to the aromatization of ODE and ODEC to 3-hydroxy-6,7,8,9-tetrahydronaphthalene (HTN) and of 2-cyclohexenone to phenol. The aromatization of ODEC to HTN is stereospecific and involves the trans… 
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References

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Aromatization of a bicyclic steroid analog, 3-oxodecalin-4-ene-10-carboxaldehyde, by liver microsomal cytochrome P450 2B4.
TLDR
3-oxodecalin-4-ene-10-carboxaldehyde was synthesized as a bicyclic analog of the aldehyde that is known to be the terminal intermediate in the enzymatic conversion of androgens to estrogens and the conversion of the bicyclic model compound to HTN was shown to be similar to that of the steroid aromatase reaction.
Identification of p-hydroxybenzaldehyde as the ligand in the green form of old yellow enzyme.
TLDR
A ligand of low molecular weight which imparts a distinctive charge-transfer absorption to the enzyme, making it green in color is identified by removal from the enzyme and characterization of its optical spectrum and subsequent mass spectral analysis.
On the enigma of old yellow enzyme's spectral properties.
TLDR
The observed phenomena and existing literature data lead to the conclusion that the only model from which no apparent inconsistencies emerge is that of a very complicated network of hydrogen-bonded structures in the protein.
Interaction of phenols with old yellow enzyme. Physical evidence for charge-transfer complexes.
TLDR
Evidence is presented that the changes in absorption spectrum obtained on complex formation between Old Yellow Enzyme and phenolic compounds are due to charge-transfer interactions and that it is the phenolate anion, rather than the conjugate acid, which is responsible for the charge- transfer interaction.
The active site of aromatase cytochrome P-450. Differential effects of cyanide provide evidence for proximity of heme-iron and carbon-19 in the enzyme-substrate complex.
TLDR
It is proposed that the opposite effects on cyanide-iron coordination are due to the proximity of the heme-iron and C-19 of androstenedione in the enzyme-substrate complex, which results in steric exclusion of cyanide from the active site by the C- 19 methyl group of and Frostenedione.
Kinetic isotope effects in the oxidation of isotopically labeled NAD(P)H by bacterial flavoprotein monooxygenases.
TLDR
Reduction of enzyme-bound FAD by (4R)-[4-2H]NAD(P)H in pre-steady-state assays reveals intrinsic deuterium isotope effects of 10 +/- 2 on this redox step, which suggests that these bacterial phenolic monooxygenases balance out internal transition states such that no single barrier is fully rate limiting.
Purification and characterization of morphinone reductase from Pseudomonas putida M10.
TLDR
Steady-state kinetic studies suggested a Ping Pong (substituted enzyme) kinetic mechanism; however, product-inhibition patterns were inconsistent with a classical Ping PONG mechanism.
Isolation of old yellow enzyme in free and complexed forms.
TLDR
Preliminary studies on the chemical nature of the material bound to old yellow enzyme are described, and similar charge transfer complexes formed by the enzyme with quinoline derivatives are reported.
[121] Preparation of tritium-labeled substrates
Publisher Summary This chapter discusses the preparation of tritium-labeled substrates. The ready availability of sodium borohydride-2- H 3 makes possible simple syntheses of many substances that are
Old Yellow Enzyme. The discovery of multiple isozymes and a family of related proteins.
TLDR
Both recombinant enzymes showed considerable similarity to two proteins in the GenBank/EMBL data bank, a 60,000-dalton bile acid-inducible polypeptide in Eubacterium sp.
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