Pentane Inhibition of the Egg-white Lysozyme-induced Cell Lysis of Micrococcus lysodeikticus

Pentane inhibited the cell lysis of Micrococcus lysodeikticus by egg-white lysozyme, when added to the lysozyme solution before mixing the cells. The pentane inhibition was not observed when pentane was added either before to the cell suspensions or to the cell-lysozyme mixture. The degree of pentane inhibition was proportional to the concentration of pentane, and the maximum inhibition was achieved with about 5% pentane close to the saturation point. On the other hand, pentane did not inhibit the hydrolysis of glycol chitin by the lysozyme, showing that the β-1,4-glucosaminidase activity of lysozyme remained unchanged. The inhibitory action of pentane on the lysozyme-induced cell lysis was of a competitive nature. The pentane inhibition had no ph-dependence, but it was influenced by the ionic strength of the buffer used as solvent.

When the lysozyme solution was treated with pentane, a characteristic ultraviolet spectrum of lysozyme was produced; a blue shift with a minimum at 280 nm and a trough at 291 nm. The degree of spectral change at 280 nm depended on the concentration of pentane. Pentane was, therefore, found to interact with egg-white lysozyme to affect the conformation and enzymatic activity of lysozyme. The mechanism of pentane inhibition on the lysozyme-induced cell lysis was discussed.