A method of affinity chromatography which is a potent tool for isolation of the trace vitamin Blz binding proteins has been developed. The affinity ligand was prepared by partial acid hydrolysis (0.4 N HCl, 64 hours, room temperature) of the amide groups of the unsubstituted propionamide side chains of the corrin ring of vitamin Blz. The resultant mixture of mono-, di-, and tricarboxylic vitami...

This paper describes a protocol for the preparation of highly purified A (A1 and A2) and B chains of the plant toxin, ricin, and biochemical and biological characterization of these proteins. Intact ricin was bound to acid-treated Sepharose 4B and was split on the column into A and B chains with 2-mercaptoethanol. The A chains were eluted with borate buffer containing 2-mercaptoethanol. A1 and ...

A method of affinity chromatography which is a potent tool for isolation of the trace vitamin Blz binding proteins has been developed. The affinity ligand was prepared by partial acid hydrolysis (0.4 N HCl, 64 hours, room temperature) of the amide groups of the unsubstituted propionamide side chains of the corrin ring of vitamin Blz. The resultant mixture of mono-, di-, and tricarboxylic vitami...

Two types of proteoglycan subunits were obtained from bovine cornea, the first mainly composed of proteochondroitin sulphate and the second of proteokeratan sulphate. These two fractions can be obtained from the tissue as an aggregate, and are able to recombine each other after separation, to re-form the original structure. In order to investigate collagen-proteoglycan interactions, type-I coll...

The carcinoembryonic antigen (CEA) active glycoproteins from perchloric acid extract of liver-metastasized primary colon tumor have been separated by concanavalin A Sepharose (Con A Sepharose) chromatography. The CEA activities separated by Con A Sepharose chromatography were designated as loosely bound and tightly bound which, respectively, eluted on the Con A Sepharose column between 0.12 and...

In terms of the rate of accumulation of alpha-aminoisobutyric acid, mammary epithelial cells from mature virgin mice respond rapidly to insulin covalently bound to sepharose particles, but do not respond initially to soluble insulin in vitro. The response to insulin-sepharose is prevented if the cells are first exposed to insulin. These observations may provide new insight into the dynamics of ...

The influence of varying the amount of wheat germ agglutinin immobilized on Sepharose beads on the binding of glycoproteins to these beads was investigated. A series of wheat germ agglutinin-Sepharose gels containing between 0.10 and 10.0 mg of lectin/ml of gel was prepared, and the actual lectin content was established by acid hydrolysis of the gel followed by analysis of glycine, a major amin...

Conversion of pepsinogen to pepsin at acid pH involves an intramolecular reaction in which the unproteolyzed zymogen cleaves itself. This conclusion is based upon experiments in which pepsinogen, at low concentrations, was activated in the presence of substrate, hemoglobin. Under these conditions, the activation of pepsinogen is independent of pepsinogen concentration, and addition of pepsin do...