EFFECTS OF HYDROXYLYSINE ON THE GROWTH AND MORPHOLOGY OF RHIZOBIUM-LEGUMINOSARUM BV PHASEOLI

It was found that both bacteroids and free-living cells of Rhizobium l eguminosarum by. phaseoli were highly susceptible to hydroxylysine (Hy l) and the inhibition of RNA and/or protein synthesis caused by the hy droxyl residue of Hyl appeared to be responsible for the growth inhibi tion. The size of free-living cells was enlarged by the addition of Hy l and some cells reached around 5 mu m, which were close to the length of bacteroids. Under the same condition, the polyhydroxybutyrate (PHB ) content in the cells was conspicuously increased. These results sugg est that Hyl is not only a notable growth inhibitor of Rhizobium bacte ria but also plays a role in a differentiation to bacteroids.