Christian Lombart

The effect of turpentine-induced inflammation on rat liver glycosyltransferases and golgi complex ultrastructure

Turpentine-induced inflammation in the rat caused a 1.6--2.3-fold increase in liver homogenate sialyl-, galactosyl- and N-acetylglucosaminyltransferase total and specific enzyme activities. Peak transferase activities were achieved at about 40 h after turpentine injection; the rise and fall of these activities corresponded to a similar rise and fall in serum haptoglobin levels. Sialyl- and N-acetylglucosaminyltransferase activities were measured in both liver homogenates and Golgi-enriched membranes at 24 h after turpentine injection; both total and specific enzyme activities doubled in the homogenates following turpentine treatment but in the Golgi-enriched membranes only the total enzyme activities doubled while the specific enzyme activities increased only by about 20%. These findings suggest that turpentine injection results in an increase of Golgi complex protein relative to total cellular protein. This conclusion was supported by electron microscopic studies of rat liver at various times after turpentine injection. The increased glycosylation potential of the liver and the proliferation of liver Golgi complex may play an important role in the turpentine-induced secretion of acute-phase glycoproteins.

Préparation et propriétés physiqes des haptoglobines de lapin et de rat

Abstract Rabit haptoglobin is obtained by chromatography of DEAE-cellulose. The purification of rat haptoglobin required three chromatographies on DEAE, CM- and TEAE-cellulose. The principal physical constants of these two proteins are given and they are compared with those of human haptoglopin HP 1-a.

A novel and specific method for the purification of hemoglobin-binding proteins

Abstract A simple, low-cost, affinity chromatography system is described which allows the purification of various hemoglobin-binding proteins. This procedure is successfully applied to the isolation of hemoglobin-binding protein from mammalian and avian plasma. This affinity chromatography system can be reused many times without any modification of its properties.

Isolement et propriétés physico-chimiques de l'hémopexine de rat

Summary Rat hemopexin was purified by a procedure involving three different steps : ammonium sulfate precipitation, rivanol precipitation and DEAE - cellulose chromatography with concave gradient of molarity. Purity of the preparation was checked by three different methods : analytical ultracentrifugation, immunoelectrophoresis and acrylamide gel electrophoresis. The principal physical properties were studied. The amino acid and carbohydrate composition was determined and compared with that of human and rabbit hemopexin.

Composition chimique des haploglobines de lapin et de rat

Resume The composition of the proteic part and of the glucidic part of rabbit and rat haptoglobins are given. These results are compared with data given by human haptoglobin Hp 1-1 analysis. In spite fo some analogies, the three protein are different.

Structural studies of glycans isolated from rat plasma hemopexin

After exhaustive pronase digestion, purification by gel filtration and affinity chromatography on concanavalin A, three glycopeptide fractions were obtained from rat hemopexin. Two fractions (I and II) were concanavalin A non-reactive and one (III) was concanavalin A reactive. On the basis of carbohydrate composition, methylation analysis and proton nuclear magnetic resonance spectroscopy, the primary structure of the glycan in fraction III is proposed as being a mixture of mono- and di-sialo-diantennae of the N-glycosidic, N- acetyllactosamine type. Hydrazinolysis of glycopeptides not binding to concanavalin A yielded mixtures of oligosaccharides for both fractions. These oligosaccharides were separated by HPLC; the molar composition of each of them is given. These data suggest that rat hemopexin contains, among others, a diantennary structure bearing three sialic acid residues.

Characterization of a chicken hemoglobin-binding protein: A novel haptoglobin

Abstract 1. 1. Chicken hemoglobin binding protein was structurally and chemically characterized. 2. 2. This single chain protein differs greatly from all known monomeric haptoglobins which contain four polypeptide chains.

Identification of haptoglobin in chicken serum and specificity of the chicken haptoglobin-hemoglobin complex formation

1. The presence of haptoglobin in chicken serum has been demonstrated by three different techniques: gel filtration, cellulose acetate electrophoresis and fluorescence quenching. 2. Chicken haptoglobin shows a narrow species specificity; it binds only avian and reptilian but not mammalian hemoglobins. 3. Haptoglobin seems to have been subjected to profound changes during the course of evolution.