Pigeon liver

Glycerol kinase (from Candida mycoderma, E coli, rat or pigeon liver glycerokinase)... 

Walker, C.H. (1969). Reductive dechlorination of p,p -DDT by pigeon liver microsomes. Life Science , 111-115. 

A phospho-eryZ/iro-pentulokinase and a phosphoriboisomerase are found in spinach.184(d) Enzymes present in mammalian liver, in pigeon liver, and in bacteria catalyze the reaction of ATP with D-ribose 5-phosphate, giving... 

An enzyme system in pigeon liver is able to transfer the acetyl group from... 

This interpretation offered by Ogston was confirmed by further isotope experiments (Potter and Heidelberger, 1949 Martius and Schorre, 1950). Ochoa and his colleagues also demonstrated that in pigeon-liver preparations which had been freed from aconitase, thus preventing isomerization between citrate and isocitrate, citrate was the product of the condensation of oxaloacetate and acetate. 

Isotopes were not available in van t Hoff s day. My student generation was taught that an asymmetric carbon atom was a carbon atom attached to 4 chemically different groups. When isotopes of carbon, UC and 13C, were first applied as tracers to study carbohydrate metabolism, the entire emphasis was on the chemical similarity of 11C and 13C to the more abundant isotope 12C. Thus, it was of pressing interest to determine whether CO 2 participated in the oxidation of carbohydrate in animal tissues, a conclusion strongly suggested by the demonstration in Krebs laboratory, that pyruvate and oxalacetate behaved alike in pigeon liver, and by Wood and Werkman s earlier demonstration that some he-... 

Pantothenic acid occurs in foods both in the free form and bonded to coenzyme (CoA) or acyl carrier protein (ACP) therefore hydrolysis is needed to extract it totally. Since it is degraded by acid and alkaline hydrolysis, only an enzymatic digestion can be applied. Enzyme hydrolysis with papain, diastase, clarase, takadiastase, intestinal phosphatase, pigeon liver pantetheinase, or combination of them has been used. 

They stated further that, the new adaptive enzyme catalyzing Reaction 3 appears to be similar to the malic enzyme of pigeon liver, although strictly DPN (instead of TPN)-specific. The coenzyme specificity explains the ready occurrence of Reaction 1. Therefore, the authors showed that exogenous NAD was required for the overall reaction (malic acid -> lactic acid), but because this activity was measured manometrically, they never demonstrated the formation of reduced NAD. Similarly, they did not attempt to show that pyruvic acid was the intermediate between L-malic acid and lactic acid. Instead, the formation of pyruvic acid was inferred from the NAD requirement and because the malic acid dissimilation activity remained constant during purification while the lactate dehydrogenase activity decreased (14). In fact, attempts to show any appreciable amounts of pyruvic acid intermediate failed (22). 

It is not surprising that the pyruvic acid intermediate seemed plausible because in a paper earlier in that same year (23), the authors described a malic enzyme from pigeon liver. This enzyme was shown to form appreciable amounts of pyruvic acid from malic acid, but it was NADP instead of NAD specific. The end product was shown to be pyruvic acid by spectrophotometric assay involving lactate dehydrogenase. 

In the early 1940s, before the discovery of 14C and when acetyl-coenzyme A was unknown, two research groups used the stable isotope 13C and mass spectrometers to study carbon flow in the TCA cycle. Pyruvate and 13C02 were added to pigeon liver preparations to form carboxy-labeled oxaloacetate. Malonate was added to stop the TCA cycle at succinate. The expected result was that half of the 13C would be found in succinate and the other half in C02 (fig. 13.10). 

C. Lysergic acid and related alkaloids Lysergic acid derivatives (30) Isolated rat liver Chanoclavine (31) Pigeon liver preparation... 

Several key reactions of this type are also performed by mammalian liver preparations. Thus, lysergic acid derivatives of type 30 are susceptible to N-(6)-demethylation and to side-chain hydroxylation by isolated rat liver preparations (46) and in a direct parallel to its normal biogenesis (66, 67), elymoclavine (32) is produced, although in low yield, from chanoclavine (31) in the presence of a commercial preparation from pigeon liver (77, 68). 

Xylitol DH(Xylu RD) Pigeon liver Xylitol L-Xylulose NADP B... 

Malate DH Pigeon liver L-Malate Pyruvate NADP A... 

The properties of 7a-hydroxylase from pigeon liver microsomes305 and from rat liver306,307 have been further described, and new assay methods are available.308,309 Free cholesterol, rather than a cholesteryl ester, was the preferred substrate for the enzyme from rat liver microsomes,310 and the substrate pool for the hydroxylase was about one third of the total amount of cholesterol present in the microsomal preparation.309 Cholesterol 7a-hydroxylase activity is more sensitive to thyroid function than are the activities of the enzymes responsible for cholesterol synthesis,311 and (22f )-22-aminocholesterol, although having no effect on serum or liver cholesterol levels in rats, drastically reduced 7a-hydroxylase activity.312... 

Acetyl-CoA arylamine N-acetyltransferase was purified from pigeon liver by using steps involving protamine sulfate, ammonium sulfate fractionation, and affinity chromatography on immobilized amethopterin. Figure 9.20 shows a representative chromatogram. In another study, Thomas et al. (1990) used tryptamine as the substrate. In addition, whereas the study by Manneus et al. (1990) appeared to require pure enzyme, Thomas s study did not. 

Inhibition of Crude Pigeon Liver DHFR by Triazines (202), 31... 

In the same year, Ruben and Kamen obtained direct evidence for this hypothesis by demonstrating fixation of C 02 in rat liver. Furthermore, Evans and Slotin successfully isolated radioactive a-ketoglutaric acid from malonate-poisoned pigeon liver mince which had been incu-... 

Wood and coworkers have demonstrated that pigeon liver mince poisoned with malonate is unable to convert C 02 into isotopic succinate but can direct the isotope into malate and fumarate as well as into the a-carboxyl of a-ketoglutarate (see Fig. 5). On the other hand, non-poisoned liver possesses the ability to anaerobically fix C 02 in succinic acid as well as fumaric and malic acids. The dicarboxylic acids invariably contain the isotopic carbon predominantly in their respective carboxyl groups. These important experiments provide conclusive proof for two main concepts. First, that malonate specifically inhibits succinic acid dehydrogenase and hence blocks completely the formation of succinic from fumaric acid. Secondly, there must be two routes by which succinate is formed. By the first pathway, pyruvate can condense with... 

Evans, E. A. Jr., and Slotin, L. Carbon dioxide utilization by pigeon liver. J. Biol. Chem. 141, 439-450 (1941). 

Diaz Gomez MI, Godoy Hm, Villarruel MC, et al. 1983. No response of pigeon liver to dimethylnitrosamine acute effects. Cancer Lett 18 157-162. 

G14. Greenberg, G. R., Incorporation of carbon labeled formic acid and carbon dioxide with hypoxanthine in pigeon liver homogenates. Arch. Biochem. 19, 337-339 (1948). 

L2. Lagerkvist, U., Biosynthesis of guanosine 5 -phosphate. II. Amination of xanthosine 5 -phosphate by purified enzyme from pigeon liver. J. Biol Chem. 233. 143-149 (1958). 

In the above equations Ajj, from the work of Jacobson, represents the relative rates of acylation of aromatic amines having substituents X by means of pigeon liver acetyl transferase, e represents the calculated electron densities on the nitrogen atom made by Perault and Pullman. Equation 22 accounts for only 47% of the variance in the data while eq 23 accounts for 99%. Thus it appears that quantum mechanically obtained electron densities can be extremely useful to the medicinal chemist. In this way the relative electron density on each atom in the molecule can be found and through regression analysis the relative importance of this density at one or more points in the molecule can be evaluated. This approach offers, in principle, a great advantage over the use of a. 

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