Liver Of Domestic Fowl Research Articles

Acid lipase in the liver of domestic fowl: Subcellular localization and some properties.

Most of the lipase in the liver of domestic fowl was acid lipase, found in the 11,700 × g pellet of the liver. About two-thirds of the enzyme in the pellet was solubilized in hypotonic solution. The solubilized lipase was stable in 40% ethylene glycol at — 70°C for 40 days, but was labile during chromatographies even with 20 % ethylene glycol at 4°C. The molecular weight of the lipase was about 34,000 by Sephacryl S-300 gel filtration, and the pi was about 5.4 by isoelectric focusing. The enzyme had its maximum activity at pH 6.0, and 40°C, and was stable below 40°C. Bovine and chicken serum albumins activated the enzyme. Ca2 +, Mg2 +, Mn2 +, and Zn2+ increased the lipase activity, but EDTA decreased the activity. CHAPS and octyl glucoside increased the lipase activity at low concentrations, but other detergents greatly inhibited the lipase activity. Serum of laying hens greatly decreased the lipase activity.

Purification and characterization of cholyl-CoA: taurine N-acetyltransferase from the liver of domestic fowl (Gallus gallus).

The enzymological basis for the ability of mammalian liver to conjugate bile acids with both glycine and taurine, and for non-mammalian liver to make only taurine conjugates, was investigated. The taurine-conjugating enzyme has been purified 1200-fold from the liver of domestic fowl and its properties compared with those of the glycine/taurine-conjugating enzyme from bovine liver [Czuba & Vessey (1980) J. Biol. Chem. 255, 5296-5299]. The enzyme from both species followed a Ping Pong mechanism. The enzymes were also similar with respect to their affinity for taurine, although the enzyme from domestic fowl would not bind glycine. The affinity of both for cholyl-CoA was quite similar, too, and both enzymes were inhibited reversibly by p-mercuribenzoate. The enzymes, however, were quite different in size. The enzyme from domestic fowl had a mol.wt. of 63000-65000 by both gel filtration and sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. This is approx. 15 000 mol.wt. units larger than the enzyme from bovine liver, and suggests a loss of genome over the course of evolution as the basis for the altered specificity at the amino-acid binding site.

Metabolism of glucose-U-14C in vitro in adipose tissue from embryonic and growing chicks.

Metabolism of glucose-U-14C in vitro in adipose tissue from embryonic and growing chicks.