Wesley C. Starbuck

A computer program for the calculation of amino acid analysis data

Abstract A program has been written for the computation of the data from amino acid analysis. This program will accept data both from integrators and from the hand calculation method. The program is written in a common language and is divided into two parts so as to convert the analytical data from the amino acid analyzer into several useful forms as desired. The first part calculates amino acid analysis of protein hydrolyzates and the second part calculates the composition of peptides.

Carboxyl-terminal sequence of the glycine-arginine-rich histone from bovine lymphosarcoma, novikoff hepatoma and fetal calf thymus

Abstract 1. 1. The glycine-arginine-rich histones isolated from bovine lymphosarcoma and Novikoff hepatoma have been found to have virtually the same amino acid compositions as that of fetal cal thymus and calf thymus published previously 8,9 . 2. 2. The glycine-arginine-rich histones isolated from fetal calf thymus, bovine lymphosarcoma and Novikoff hepatoma were cleaved with cyanogen bromide to yield two peptides. The C-terminal CN-2 peptide for each histone was isolated by the use of Sephadex G-100. The C-terminal CN-2 peptide for each of these three tissues was found to have the same amino acid composition as that from calf thymus 12 . 3. 3. The C-terminal peptides, CN-2, of bovine lymphosarcoma, fetal calf thymus and Novikoff hepatoma were hydrolyzed with trypsin. In each case five peptides were obtained by peptide mapping and ion-exchange chromatography. The amino acid compositions of these peptides were identical for each of the tissues and to that found for calf thymus previously. 4. 4. It was concluded that the C-terminal portion of the glycine-arginine-rich histones isolaetd from these four tissues are identical with each other and with that of pea seedling 11 .

Hydroxyethylation of amino acids in plasma albumin with ethylene oxide

The reaction of ethylene oxide with amino acids in bovine plasma albumin was studied under various conditions of pH and time. Ethylene oxide reacted with arginyl, cystyl, histidyl, lysyl, methionyl and tyrosyl residues in albumin. The maximal reaction of arginyl, histidyl, lysyl and tyrosyl residues occurred at pH values equal to or greater than the pK of the respective reacting groups. The reaction of ethylene oxide with the above amino acid residues resulted in the formation of 21 new peaks detected by chromatograpic analysis of the amino acids. The amino acids from which most of these products originated were detected by labeling the albumin biosynthetically with individual radioactive amino acids before hydroxyethylation. The major product of hydroxyethylation of lysine was apparently Nϵ[tris(2-hydroxyethyl)]lysine, since it corresponded to the Nϵ[tris(2-hydroxyethyl)]-lysine, prepared by direct synthesis, with respect to mobility in several chromatographic systems. The accessibility of some lysyl and methionyl residues in albumin to ethylene oxide may be dependent upon a partial change in the tertiary structure of albumin, resulting from the reaction of cystyl residues in albumin with ethylene oxide.

LARGE-SCALE NINHYDRIN RESERVOIR SYSTEM FOR AUTOMATIC AMINO ACID ANALYSIS.

Abstract Automated amino acid analysis (1) has been markedly accelerated by the development of commercial models for this purpose. The addition of further instrumentation (2) has allowed utilization of the instruments on a continuous basis. Continuous operation of several automatic amino acid analyzers requires large reserves of buffers for efficient utilization of machine time. Column buffers are generally prepared in large quantities, however, ninhydrin reagent is normally prepared in 4-liter batches for each machine. This quantity of ninhydrin is only sufficient for about 2 weeks of continuous operation. One of the problems of enlarging the original type of ninhydrin system (1) is the necessity of providing several equally large containers for oil or water in order to maintain nitrogen gas at a slight positive pressure over the ninhydrin reagent for the exclusion of air. Space limitations in commercial instruments restricted the enlargement of this system. This paper deals with the description and operation of a large-scale ninhydrin system employing constant nitrogen pressure (3) without the use of a hydrostatic system. The system can be easily adapted to commercial instruments at a nominal cost (about

Structural Analysis of the Glycine-rich, Arginine-rich Histone III. SEQUENCE OF THE AMINO-TERMINAL HALF OF THE MOLECULE CONTAINING THE MODIFIED LYSINE RESIDUES AND THE TOTAL SEQUENCE

100).