TABLE 1.

Summary of the estimated percentage of secondary structure of commercial and recombinant ubiquitins

	X-ray	Commercial	Monomer	Dimer	Tetramer
α-Helix*	16†	16	14	14	13
β-Sheet	32	33	34	33	36
Turn and random coil	52	51	52	53	51

^*Percentages of the secondary structure of recombinant ubiquitins were estimated from the far-UV CD spectra (195–260 nm) using the neural network program, CDNN. Thirty-three basis sets were used in the calculations.

^†Percentage was calculated from the x-ray structure (pdb ID, 1ubq).