[Small-angle diffuse x-ray scattering on fine muscle filaments].

Theoretical small-angle diffuse scattering curves from muscle thin filament models have been calculated. The curves reveal a maximum at 115' scattering angle. It has been shown that the maximum is due to the pitch of F-actin helix. Theoretical curves are in good agreement with the earlier obtained curves of small-angle diffuse scattering from F-actin dilute solutions.