Amino acid composition is one of the most basic characteristics of the proteome, and will provide various insights into protein chemistry and evolution. Bacterial organisms are known to have strikingly diversified amino acid compositions depending on the GC-content, habitat environment and energetic costs for biosynthesis. Therefore it is a fundamental question whether any kind of physicochemic...

Dual-radiolabelled avian tracheal secretions were obtained by giving Na235SO4 and D-[1-3H]glucosamine simultaneously into the lumen of the trachea in preparations in vitro. These secretions comprised fibrillar, gelatinous and soluble-phase mucins. These were eluted as single components in the non-retarded fractions from Bio-Gel A-15m. Although no evidence of the presence of subunit structure wa...

1. The activity of the hydrogen ion, in a system containing 0.00280 mols of NaAc, 0.520 mols of NaCl per liter, and varied amounts of HCl or NaOH has been investigated. The average value of pK' for acetic add in this system is about 4.37. 2. The effect of the addition of various amounts of HCl and NaOH to a system containing 0.00280 mols of NaAc, 0.520 mols of NaCl, and a known number of cells ...

The physicochemical properties and amino acid composition of chymotrypsinogen B have been examined. The partial specific volume has been determined as 0.733 ml per g. From sedimentation velocity measurements, siO,, has been found to be 2.58 S at pH 3.0. At pH values above 4, the zymogen dimerizes as indicated by both sedimentation velocity and approach to sedimentation equilibrium measurements....

We separated the respirable dust and other size fractions from Apollo 14 bulk sample 14003,96 in a dry nitrogen environment. While our toxicology team performed in vivo and in vitro experiments with the respirable fraction, we studied the size distribution and shape, chemistry, mineralogy, spectroscopy, iron content and magnetic resonance of various size fractions. These represent the finest-gr...

Shellac in its acid form undergoes aging, resulting in the change of its physicochemical properties. Therefore, various shellac types were investigated as free films prepared from ammoniacal solutions and as micronized powder in its acid form. Due to its acidic character, shellac shows a pH-dependent solubility. The dissolution properties of shellac films prepared from ammoniacal solution were ...

Attempts to crosslink metallothionein through lysine residues have resulted in trapping of octameric structures. Two such polymers have been characterized. They are of a critical size for glomerular filtration, and unique tissue distributions of cadmium arise when they are injected into rats.

Black garlic (BG) is a processed garlic product prepared by heat treatment of whole garlic bulbs (Allium sativum L.) at high temperature under high humidity for several days, resulting in black cloves with a sweet taste. BG has recently been introduced to the Korean market as a product beneficial to health. To clarify how BG changes during the 35 day aging period, the physicochemical characteri...

The physical properties of bovine prothrombin preparations have been described in this journal (1). Although methods for obtaining bovine thrombin are now also available (a), the physical properties, including the molecular weight, have not been described. Here we report values for the sedimentation coefficient, diffusion coefficient, intrinsic viscosity, frictional ratio, molecular weight, and...

[1] Understanding the processes controlling chemical sedimentation is an important step in deciphering paleoclimatic conditions from the rock records preserved on both Earth and Mars. Clear evidence for subaqueous sedimentation at Meridiani Planum, widespread saline mineral deposits in the Valles Marineris region, and the possible role of saline waters in forming recent geomorphologic features ...