Ultrastructural comparison of the tailed and tailless P-protein crystals respectively of runner bean (Phaseolus multiflorus) and garden pea (Pisum sativum) with tilting stage electron microscopy

Summary The periodicity of striation, discovered to measure 12 nm in the tailless P-protein crystal ofPisum sativum, is compared with that known in the central body of the tailed P-protein crystal ofPhaseolus multiflorus. A preliminary model advanced to explain the coarse striation in tails accounts for both the wavy outline in longitudinal section and the nearcircular outline in transverse section.