HYDANTOIN DRUGS INHIBIT POLYMERIZATION OF PURE MICROTUBULAR PROTEIN

  • 1 January 1978
    • journal article
    • research article
    • Vol. 204  (1) , 189-194
Abstract
5,5-Diphenylhydantoin or 5-(4-hydroxyphenyl)-5-phenylhydantoin, 3.6 .times. 10-4 M, inhibited polymerization of purified pig brain tubulin 50% as measured by viscosometric assay and estimation of tubulin length by EM. 5,5-Diphenylhydantoin did not bind to the low MW fraction of tubulin or to GTP; it displaced colchicine weakly from its binding site. 5,5-Diphenylhydantoin did not depolymerize established microtubules, indicating that it differs from colchicine in site and mode of action. [5,5-Diphenylhydantoin inhibition of tubulin could play a role in the toxicity of this drug.].