[Nature of the orientation of the tryptophan residues in the myosin and actin from striated muscle fiber].

The mode of tryptophan residue orientation in myosin and action myofilaments of the muscle fiber was studied using polarized ultraviolet (UV) fluorescent microscopy of the muscle fiber was studied using polarized ultraviolet (UV) fluorescent microscopy technique. During an elective extraction of proteine from thick and thin myofillaments changes in UV fluorescence anisotropy of muscle fibers were detected, thus suggesting that tryptophanil residues in myosin may be oriented by their own short axes mostly parallel, but in actin--perpendicular to the muscle fiber axis. The use of acrylamide, an UV fluorescence quencher, is proposed for the control of extraction electivity of proteins from muscle fibers.