Tumor-associated antigens (TAAs) expressed on tumor cells from cattle with enzootic bovine leukosis were divided into three groups by using 13 monoclonal antibodies: common TAA; partially common TAA; and individually distinct TAA. TAA was extracted from tumor cells and purified by ion exchange chromatography on diethylaminoethyl-cellulose and isoelectric focusing. The common TAA, which was dete...

Preliminary work revealed that nitrate reductase in crude extracts prepared from leaves of certain corn genotypes as well as soybeans could utilize NADPH as well as NADH as the electron donor. Isoelectric focusing and diethylaminoethyl cellulose chromatography confirmed previous findings that NADH and NADPH activities could not be separated, which suggests the involvement of a single enzyme. Ni...

Recent physicochemical(l,2) and immunochemical(3) studies from our laboratory have shown that human ceruloplasmin is a labile protein the properties of which are readily modified by a variety of experimental conditions. Our previous data, however, indicated that crystalline ceruloplasmin was a single protein. This is at variance with results from other laboratories which have shown that chromat...

Human erythrocyte glucose 6-phosphate dehydrogenase (o-glucose 6-phosphate :nicotinamide adenine dinucleotide phosphate oxidoreductase, EC 1.1.1.49) was purified by column chromatography with diethylaminoethyl cellulose, calcium phosphate gel, carboxymethyl cellulose, diethylaminoethyl Sephadex, and carboxymethyl Sephadex. A homogeneous preparation was obtained in over-all yield of about 50%. T...

6-Mercaptopurine was found to inhibit the growth of cultured human lymphoma P3HR-1 cells and the incorporation of [3H]-uridine into trichloroacetic acid-precipitable materials of the cells. One of the derivatives of 6-mercaptopurine, 6-mercaptopurine ribonucleoside triphosphate (6-thio-ITP), was found to inhibit in vitro RNA synthesis (both engaged and free enzyme activities) of the isolated nu...

Procedures are described for the preparation of highly purified streptokinase by column chromatography on diethylaminoethyl cellulose and by column electrophoresis in a sucrose density gradient. Preparations chromatographed at least twice on diethylaminoethyl cellulose are shown to be essentially monodisperse on the basis of ultracentrifugal and gel electrophoretic analyses and constancy of spe...

Tyrosyl-, arginyl-, leucyl-, and phenylalanyl-tRNA synthetase activities were measured in extracts from three root sections of 3-day-old pea seedlings. The sections 0 to 2, 3 to 7, and 8 to 22 millimeters from the root tip were chosen to represent the regions of cell division, elongation, and maturation, respectively. The specific activity for each aminoacyl-tRNA synthetase was highest in the 0...

Egg lectin of Rana japonica, which specifically agglutinates transformed cells but does not agglutinate nontransformed cells and erythrocytes, has been isolated by gel filtration and successive ion-exchange chromatographies on diethylaminoethyl cellulose and carboxymethylcellulose columns and has been characterized as a homogeneous carbohydrate-free protein with a relative molecular weight of 1...

A soluble enzyme system from suspension cultures of Acer pseudoplatanus L. converts d-glucose 6-phosphate to myoinositol. A Mg(2+)-dependent phosphatase, present in the crude extract, hydrolyzes the product of the cyclization, myoinositol monophosphate, to free myoinositol. Further purification of the enzyme system by precipitation with (NH(4))(2)SO(4) followed by diethylaminoethyl cellulose ch...

Human erythrocyte glucose 6-phosphate dehydrogenase (o-glucose 6-phosphate :nicotinamide adenine dinucleotide phosphate oxidoreductase, EC 1.1.1.49) was purified by column chromatography with diethylaminoethyl cellulose, calcium phosphate gel, carboxymethyl cellulose, diethylaminoethyl Sephadex, and carboxymethyl Sephadex. A homogeneous preparation was obtained in over-all yield of about 50%. T...