Table 1. k_obs/I Values for KLK6 ABP Analogues^a.

code	compound sequence	KLK6 kobs/I (M–1 s–1)	95% CI	KLK8 kobs/I (M–1 s–1)	95% CI
round 1
1	Yn–Thr(Z)–Ala–Phg–Phg(4-guan)PP	220	210–230
2	Yn–Thr(Z)–Chg–His(Z)–Phg(4-guan)PP	30	24–36
3	Yn–Thr(Z)–Cha–His(Z)–Phg(4-guan)PP	46	40–52
4	Yn–Asp(Chx)–Cha–His(Z)–Phg(4-guan)PP	54	51–57
5	Yn–Thr(Z)–Ala–Dht–Phg(4-guan)PP	250	240–260
6	Yn–Thr(Z)–Ala–Tyr(Z)–Phg(4-guan)PP	7	5–9
7	Yn–Thr(Z)–Ala–Ser(Z)–Phg(4-guan)PP	43	33–53
8	Yn–Thr(Z)–Ala–Dab(Z)–Phg(4-guan)PP	11	7–15
round 2
9	biotin–Ahx–Thr(Z)–Ala–Dht–Phg(4-guan)PP	220	210–230
10	biotin–Ahx–Thr(Z)–Cha–Dht–Phg(4-guan)PP	420	400–440	71	68–84
11	biotin–Ahx–DPhe–Cha–Dht–Phg(4-guanPP	210	200–220	0	0
12	biotin–Ahx–DhPhe–Cha–Dht–Phg(4-guan)PP	140	110–170	0	0
13	biotin–Ahx–DPhe–Lys–Dht–Phg(4-guan)PP	250	230–270
14	biotin–Ahx–DPhe–DLys–Dht–Phg(4-guan)PP	550	520–580	73	68–78
15	biotin–Ahx–DPhe–Cha–Ser(Ac)–Phg(4-guan)PP	150	140–160	20	14–26
round 3
16	biotin–Ahx–DPhe–Cha–Dht–ArgPP	1300	1230–1370	150	141–159
17	biotin–Ahx–DPhe–Ser(Z)–Dht–ArgPP	11000	10700–11300	140	135–145
18	biotin–Ahx–DPhe–Ser(Z)–Dht–DArgPP	0	0
19	Yn–DPhe–Ser(Z)–Dht–ArgPP	3000	2880–3120
20	Yn–DPhe–Ser(Z)–Dht–DArgPP	0	0
21	Cy5–DPhe–Ser(Z)–Dht–ArgPP	1000	900–1100	40	34–46

^aThe chemical structures of each amino acid abbreviation are listed in Figure S3. Definitions of each tag are as follows: Yn = 4-pentynoic acid, biotin = d-biotin, and Cy5 = cyanine-5 with a triazole linker. Phg(4-guan)PP = diphenyl (amino(4-guanidinophenyl)methyl)phosphonate and ArgPP = diphenyl (1-amino-4-guanidinobutyl)phosphonate.