An Analysis of the Optical Rotatory Dispersion of Polypeptides and Proteins. Ii.

Circular dichroism and optical rotatory dispersion of proteins and polypeptides.

Buoyant Titration of Bovine Mercaptalbumin Chemically Modified at the Carboxyl Groups

Bovine mercaptalbumin has been modified at the carboxyl groups by means of I-ethyl-3 (3-dimethylisopropyl) carbodiimide and glycine amide. A stable derivative was obtained after modification of 54 groups. The modified protein differed only slightly from the unmodified one with respect to the optical rotatory dispersion parameters ao, bo and ~. This preparation was studied in the analytical ultr...

Tandem Synthesis and Optical Rotatory Dispersion Studies of a Novel Spiro Lactone (methyl 3-(benzo[d]thiazol-2-ylamino)-7,9-dimethyl-2,6,8,10-tetraoxo-1-oxa-7,9-diazaspiro[4.5]dec-3-ene-4-carboxylate)

Spiro compounds are of interest due to their interesting conformational features and their structural implications on biological systems. The asymmetric characteristic of the molecule due to the chiral spiro carbon is one of the important criteria of the biological activities. These structures are a widespread structural motif found as key elements of numerous drugs and designed medicinal agent...

Conformation of Proteins and Polypeptides. Ii. Optical Rotatory Dispersion and Conformation of the Milk Proteins and Other Proteins in Organic Solvents.

The study of the optical rotatory properties of synthetic polypeptides in organic solvents has contributed considerably to our understanding of the structural organization of globular proteins. However, in contrast to the extensive literature which has accumulated in the past decade on the various polyamino acids (l-3), relatively little work has been done on actual proteins in organic solvents...

Threonine deaminase from Salmonella typhimurium. II. The subunit structure.

Purified threonine deaminase of Salmonella typhimurium was found to be monodisperse and to have a molecular weight of 194,000. The protein, in 6 M guanidine HCI and 0.1 M P-mercaptoethanol, dissociates into polypeptide chains of molecular weight 48,500. Tryptic peptide analysis implies that the four component chains of the native enzyme are of identical amino acid sequence. L-Isoleucine and L-v...

Membrane optical activity: some facts and fallacies.

The circular dichroism of hypothetical, water-filled, spherical shells, 75-3500 nm in radius, with walls 7.5 nm thick, composed of poly(L-lysine) in various conformational proportions, and suspended in water, were computed from the known optical properties of this polypeptide by classical general light-scattering theory (Mie theory). Comparison of the computed curves of circular dichroism spect...