The development in vitro of particles from cytoplasm. II. Particles from hemoglobin and deoxyribonucleic acid.

Spherical particles, 1 to 10 microns in diameter, resulted from the incubation at 37 degrees C. of distilled water lysates of erythrocytes with deoxyribonucleic acid (DNA). The particles consisted of 88 per cent hemoglobin and 12 per cent DNA (dry weight basis). An unknown factor, presumably an enzyme, present only in fresh red cell lysates, was required for particle development. Particle size was a function of the pH of the reaction mixture. The pH range was 4.8-5.8. It was possible to trap extraneous proteins and polysaccharides in pockets within the hemoglobin particles during their development to the exclusion of some of the hemoglobin. The amount of any one substance so trapped was proportional to its concentration in the reaction mixture. Some practical applications of the particles, as a means for making particulate various soluble substances (enzymes, antigens, antibiotics), are suggested.