A number of methods have been described for the estimation of peptic activity, many of which are accurate and convenient for comparative experiments but none of which give results which are accurately reproducible with different preparations of the protein used. This variation is due to the difficulty involved in obtaining reproducible protein preparations… (More)
The Reversibility of Coagulation It has already been shown that the coagulation of hemoglobin appears to be reversible. One can prepare from completely coagulated hemoglobin soluble, crystalline hemoglobin which by the tests so far tried is indistinguishable from ordinary native hemoglobin (Mirsky and Mason (13)). Since hemoglobin is a typical coagulable… (More)
1. The processes of denaturation and coagulation of hemoglobin are like those of other proteins. 2. When hemoglobin is denatured it is probably depolymerized into hemochromogen. 3. When other proteins are denatured they, too, are probably depolymerized. Conversely, native proteins can be regarded as aggregates of denatured proteins. 4. The globins and… (More)
The denaturation of hemoglobin by salicylate in neutral solution is completely reversible. There is a mobile equilibrium between native and denatured hemoglobin in neutral salicylate solution. The higher the salicylate concentration the greater is the percentage denaturation. When there is a mobile equilibrium between the native and denatured forms of a… (More)
The viscosity of a protein solution is increased by the denaturation of the protein. This is true both when there is the formation of protein aggregates which occlude water and when there is no aggregation. Under certain conditions, as a result of the aggregation following denaturation, a solution containing only one per cent of protein may be converted… (More)
Lampbrush chromosomes have been observed in the growing odcytes of animals ranging from mollusks to mammals. They are present throughout the diplotene of the first meiotic division. These elongate, paired structures bear many thousands of loops projecting laterally from the main chromosomal axis, and they are characteristically accompanied in the nuclear… (More)
(Interview Transcription) I am Bruce McEwen, professor and head of the Laboratory of Neuroendocrinology at the Rockefeller University here in Manhattan. Question: What are the most important recent findings from neuroscience and epigenetic research with regard to the epidemic levels of child maltreatment and violence against children, especially also with… (More)
There is a mobile equilibrium between the native and denatured forms of trypsin which depends on the concentrations of acid, alkali, and alcohol and on the temperature. The heat of denaturation in 0.01 N hydrochloric acid calculated from the effect of temperature on the equilibrium constant is -67,600 calories per mole.
This paper is a comprehensive review of chroma-tin biology and chemistry as seen in 1968, or eight years after the beginning of this science. Chroma-tin consists of DNA complexed with proteins known as histones. It is shown that histones are comprised of five species which are very much the same in all eukaryotic creatures and conserved in amino acid… (More)
1. A method is described for estimating the heme in yeast and bees' muscles as pyridine hemochromogen. 2. The difficulties of the method are discussed. 3. The heme as given by the pyridine method is responsible for about 40 per cent of the total iron.