It has been shown by use of isolated, perfused rat kidneys that hypertensin II is a potent vasoconstrictor substance while hypertensin I is not. Hence it would appear that in intact animals the pressor activity of hypertensin I results from its rapid conversion to hypertensin II. An enzyme which effects this conversion has been procured from horse plasma in a semipurified form by means of ammon...

Polymerization-induced self-assembly (PISA) is used for the highly convenient and efficient preparation of ampholytic diblock copolymer nanoparticles directly in acidic aqueous solution. Cationic nanoparticles comprising a protonated polyamine stabilizer block and a hydrophobic polyacid core-forming block are formed at pH 2. Micelle inversion occurs at pH 10 to produce anionic nanoparticles wit...

Extracts of maize leaf sheath tissue deaminate both l-phenylalanine and l-tyrosine. The activities with both substrates are enhanced by treating the plant with gibberellic acid. Both activities decrease rapidly at the same rate when tissue is incubated in a moist atmosphere, and this decrease can be slowed by treatment with cycloheximide. The ratio of the activities was constant throughout a se...

A chitinase was purified from the culture filtrate of nigeran-degrading Arthrobacter sp. NHB-10 by precipitation with ammonium sulfate and column chromatographies on DEAE-Sephadex A-50 and Superose 12. The final preparation was homogenous in polyacrylamide gel electrophoresis. The molecular weight of the purified enzyme was 30,000 and its isoelectric point was 6.8. The optimum pH and temperatur...

A procedure is described for the purification of cytochrome c peroxidase from Pseudomonas aeruginosa involving extraction by sonication, followed by acid precipitation and chromatography on only two types of gel. The final preparation had a purity ratio A407/A280 of 4.2, and was found to be essentially pure by isoelectric focusing. The enzyme was shown to be unstable during degassing under vacu...

Exo-alpha-N-acetylgalactosaminidase has been purified 8000-fold from Clostridium perfringens by gel filtration, ion exchange chromatography, isoelectric precipitation, and negative adsorption on human O type erythrocytes. The resulting enzyme is active at physiological pH and temperature. Phenyl glycosides, oligosaccharides, mucins, glycolipids, and cell membranes are substrates for this enzyme...

Lethal and hemolytic toxins were purified by acetone precipitation, Sephadex G-50, CM-cellulose and CM-Sephadex column chromatography from the tentacles and bodies of the sea anemone Actinia equina. The isolated toxins, with a mol. wt of 19,000 determined by SDS-polyacrylamide gel electrophoresis, differed only slightly in amino acid composition and had a high tryptophan content. The isoelectri...

Acidic brain fibroblast growth factor has been purified a minimum of 35,000-fold to apparent homogeneity by a combination of differential salt precipitation, ion exchange chromatography, gel filtration, isoelectric focusing, and hydrophobic chromatography on a C4 reversed-phase HPLC column. Two microheterogeneous forms of the molecule are obtained with apparent molecular masses of 16,600 and 16...

Often plant tissues are recalcitrant and, due to that, methods relying on protein precipitation, such as TCA/acetone precipitation and phenol extraction, are usually the methods of choice for protein extraction in plant proteomic studies. However, the addition of precipitation steps to protein extraction methods may negatively impact protein recovery, due to problems associated with protein re-...

a total of 781 serum and 827 red cell samples from four populations of iran (kashan, ardestan, asrara and ardabil) were sub-typed by isoelectric focusing for group-specific componet and red cell enzyme phosphoglucomutase, locus one, respectively. heterogeneity test revealed no significant differences among the populations studied regarding both pgm1 and gc systems.