Table 2.

Structural and kinetic parameters for the 41 small apparent two-state proteins

Proteins	PDB code	Size of NS	Size of TS	Log kf	TCD(N)
Villin 14T	2VIKa	126	18	2.95	0.97
Ribosomal protein L9	1DIVb	56	14	2.86	0.88
FKBP12	1FKBa	107	23	0.63	1.30
Ubiquitin	1UBOa	76	16	3.18	1.07
Procarboxipeptidase A2	1PBAa	81	21	2.95	1.08
McrP	2HQIb	72	30	0.08	1.48
U1A	1URNa	96	18	2.49	1.20
HPr	1HDNa	85	25	1.17	1.35
Tendamistat	2AITa	75	26	1.82	1.42
CspA	1MJCa	69	15	2.28	1.14
CspB	1CSPa	67	19	3.03	1.10
Twitchin	1WITb	93	33	0.18	1.48
Titin	1TITb	89	17	1.51	1.26
FN_III	1FNF_10a	94	22	2.37	1.14
FN_III	1FNF_9a	90	36	−0.40	1.30
α-spectrin SH3 domain	1SHGc	57	15	0.61	1.35
Src SH3 domain	1FMK	57	21	1.54	1.28
Sso SH3 domain	1BF4	64	14	3.02	0.88
PI3 SH3 domain	2PNI	86	20	−0.46	1.21
Fyn-SH3 domain	1NYFa	58	16	1.97	1.22
E2P	2PDDb	43	7	4.25	0.75
Im9	1IMQb	86	14	3.17	0.93
ACBP	2ABDa	86	14	2.84	1.04
Monomeric λ-repressor	1LMBa	79	14	3.69	0.75
CD2	1HNGb	98	19	1.26	1.25
N-Ribosomal/Protein L9	1CQU	56	14	2.95	0.91
Cyt. c	1HRCa	104	14	3.08	0.84
Rd-apocyt b562	1M6T	106	16	3.70	0.81
CI2	1COAa	64	22	1.75	1.14
Protein L	2PTLa	62	14	1.78	1.13
Protein G	3GB1	56	20	2.60	1.10
mAcP	1APSa	98	32	−0.64	1.52
TNfn3	1TENa	90	24	0.46	1.24
WW domain	1PIN	34	16	4.11	0.95
Protein A B-domain	1BDC	60	10	5.08	0.71
Engrailed homeodomain	1ENH	54	12	4.57	0.83
Villin head piece	1VII	36	12	4.34	0.67
Barnase	1A2P	108	18	1.11	0.86
Ribosomal protein S6	1RIS	97	19	2.61	1.33
NTL9 (1–39)	1COU_1_39	39	15	3.13	1.51
β-hairpin (41–56)	3GB1	16	10	5.39	0.89

^a From Jackson (1998).

^b From H. Zhou and Zhou (2002).

^c References: β-hairpin (Munoz et al. 1997); 1RIS (Miller et al. 2002); T9 to D65 for src-SH3 domain (Riddle et al. 1999); E15 to F76 for protein I (Kim et al. 2000), 1 to 39 for NTL9 (1–39) (Horng et al. 2003); G1326 to T1415 for 1FNF_9 and Vall416 to T1509 for 1FNF_10 (Plaxco et al. 1997); SH3-PI3 (Guijarro et al. 1998); 1A2P (Chu and Bai 2002); 1CQU (Luisi and Raleigh 2000); 1M6T (Chu et al. 2002); 1PIN (Jager et al. 2001); 1BDC (Myers and Oas 2001); IVII (Wang et al. 2003); 1ENH (Mayor et al. 2003); 3GB1 (McCallister et al. 2000); 1BF4 (Guerois and Serrano 2000); 1SHG (Martinez et al. 1999).