Table 1.

Characterization of HIV-1_YU2 gp120 inner domain mutants

Envelope glycoprotein	Residue Location	Processing indexa	Association indexa	CD4-Ig bindinga	Cell-cell fusiona	Relative Infectivitya	sCD4 IC90 (nM)a
Wild-type YU2		1.00	1.00	1.00	1.00	1.00	90
E47A	$\stackrel{‒}{\beta 3}$	0.49	0.64	nd	nd	nd	nd
T49A	Layer 1	0.77	1.07	1.14	0.96	1.06	90
T51A	Layer 1	0.69	1.06	1.02	0.85	0.89	nd
L52A	Layer 1	0.36	0.25	0.23	0.1	0.01	nd
F53A	Layer 1	0.40	0.25	0.29	0.39	0.02	nd
D57A	Layer 1	0.65	0.62	0.91	0.86	0.54	nd
A60G	Layer 1	0.92	0.86	1.46	0.89	0.79	nd
Y61A	Layer 1	0.95	0.89	1.33	0.81	0.74	nd
T63A	Layer 1	0.98	0.99	1.79	0.43	1.11	nd
H66A	Layer 1	1.08	0.97	0.50	0.82	0.88	200
V68A	Layer 1	1.07	0.60	1.12	0.51	0.68	nd
W69L	Layer 1	0.88	0.89	0.64	1.07	0.33	>400
T71A	Layer 1	0.79	0.58	0.85	0.92	0.03	nd
H72A	Layer 1	1.02	0.33	1.11	0.56	0.04	nd
A73S	Layer 1	1.13	0.46	1.19	0.32	0.86	nd
V75A	Layer 1	0.75	0.55	0.72	0.40	0.19	nd
P76A	Layer 1	0.85	0.64	1.02	0.37	0.11	nd
T77A	Layer 1	1.66	0.56	1.52	0.95	0.65	90
D78A	Layer 1	0.69	0.51	1.13	1.03	0.11	90
P79A	Layer 1	1.09	0.64	1.29	0.90	0.54	88
N80A	Layer 1	1.21	0.65	1.24	0.97	0.99	90
P81A	Layer 1	1.18	0.61	1.10	0.89	0.81	90
Q82A	Layer 1	1.17	1.03	1.12	0.92	0.98	100
E83A	β-sandwich	0.93	0.61	0.86	0.63	0.29	70
L86A	β-sandwich	0.65	0.36	0.48	0.58	0.07	20
V89A	β-sandwich	0.56	0.22	0.97	0.57	0.01	nd
T90A	β-sandwich	0.65	0.55	1.27	0.85	0.87	20
E91A	β-sandwich	0.53	0.41	1.45	0.26	0.07	80
F93A	β-sandwich	0.37	<0.01	nd	0.01	<0.01	nd
W96A	Layer 2	1.35	0.65	0.66	2.79	0.96	110
K97A	Layer 2	1.32	0.93	0.93	0.57	0.98	110
N99A	Layer 2	1.18	0.70	0.97	1.28	0.82	nd
M100A	Layer 2	0.75	0.29	0.50	0.75	0.39	nd
E102A	Layer 2	1.36	0.79	0.81	0.83	1.03	50
Q103A	Layer 2	0.77	1.07	1.15	nd	0.79	60
Q103R	Layer 2	0.86	0.33	0.74	1.59	0.18	20
M104A	Layer 2	1.38	0.47	1.25	nd	0.21	90
E106A	Layer 2	0.86	0.61	0.90	0.59	0.58	nd
D107A	Layer 2	0.24	0.32	0.66	0.39	0.09	20
D107Q	Layer 2	0.78	0.61	0.69	0.79	0.01	nd
D107Y	Layer 2	0.14	0.31	nd	0.62	<0.01	nd
I108A	Layer 2	0.68	0.79	1.48	nd	0.43	300
I109A	Layer 2	0.95	0.44	0.49	1.95	0.41	50
I109W	Layer 2	0.96	0.39	0.35	2.40	0.34	200
S110A	Layer 2	0.69	0.62	0.83	1.04	0.09	90
S110N	Layer 2	0.73	0.66	nd	1.09	0.21	90
S110W	Layer 2	0.59	0.49	nd	0.98	0.03	20
L111A	Layer 2	0.34	0.28	0.48	0.72	0.04	>400
L111F	Layer 2	0.32	0.10	0.75	0.46	0.02	20
W112A	Layer 2	1.07	0.17	0.25	0.98	0.07	100
D113A	Layer 2	1.08	0.55	1.79	nd	0.50	30
Q114N	Layer 2	0.93	0.74	1.09	1.78	0.42	50
S115A	Layer 2	0.98	1.12	1.36	nd	0.79	150
L116A	Layer 2	1.04	0.25	0.67	0.25	<0.01	nd
F210A	Layer 2	0.51	1.33	0.56	0.85	0.06	40
P212A	Layer 2	0.88	0.93	0.65	1.85	0.76	360
I213A	Layer 2	0.37	0.48	0.62	0.92	0.04	160
I215A	Layer 2	0.34	0.45	0.46	0.85	0.01	80
Y217A	Layer 2	0.60	0.32	0.52	0.67	0.15	nd
A221G	Layer 2	1.02	0.43	0.76	1.04	0.01	nd
F223A	β-Sandwich	0.90	0.23	0.85	0.63	0.19	nd
S375W	Phe 43 cavity	0.82	0.93	1.12	0.69	0.70	20
W437R	β20-β21 loop	1.07	0.64	0.09	0.46	<0.01	nd
K487A	β25 strand	0.13	0.3	nd	nd	nd	nd
K487E	β25 strand	0.13	0.2	nd	nd	nd	nd
W69L/L111W	Layer 1/Layer 2	0.62	0.28	0.72	0.30	0.02	140
H66A/S375W	Layer 1/Phe 43	0.84	0.95	1.10	0.75	0.42	20
W69L/S375W	Layer 1/Phe 43	0.88	0.81	1.11	1.09	0.28	20
D107A/S375W	Layer 2/Phe 43	0.12	0.61	0.76	0.61	nd	nd
L111A/S375W	Layer 2/Phe 43	0.62	<0.01	1.32	0.34	0.03	20

^aThe phenotypes of the wt and mutant Env gps were determined as described in Experimental Procedures. Results represent the mean values derived from at least three experiments. Less than 20% deviation from the mean value was typically observed. nd = not determined