Colchicine binding of cell extracts from colchicine-resistant mutants of Chlamydomonas reinhardi

The colchicine-binding activity of a high speed supernatant from fourteen colchicine- and/or vinblastine-resislant mutants of Chlamydomonas reinhardi has been compared to that of wild type. Four of the mutants have reduced binding per unit protein. The low level of binding of one of these mutants is unusually stable. Three other mutants have normal initial binding levels, but show altered kinetics of decay of binding activity. Most of the mutants with altered colchicine-binding activity produce abnormally large cells. Seven other mutants showed only slight or no differences in colchicine binding from wild type.