Abstract
Physico chemical changes of ovalbumin illuminatied in the presence of methylene blue were examined. Solubility of ovalbumin was remarkably reduced, but its extents were varied with the value of pH, that of ionic strength and illumination time. Illumination brought about aggregation of protein molecules which was revealed on the ultra centrifugal patterns. Electrophoretical patterns showed that three peaks characteristic of native ovalbumin went into one peak after 24 hr and into two peaks after 48hr. After an illumination for 6 hr, titration curves showed that bound protons decreased below pH 8.0 and increased over pH 8.0. The spectra of illuminated ovalbumin were displaced upward and the absorption maximum shifted toward the longer region of wave length.