Table 1 Estimated kinetic constants for binding of full-length HIV-1 Vpr and C-terminal Vpr peptides to CypA.

ka ₁ (1/Ms)

kd(1/s)

Vpr^75-90

GCRHSRIGVTRQRRAR

1:1

0.28 ± 0.27

8.1 ± 6.1 × 10⁴

6.3 ± 4.6 × 10^-3

Vpr^75-90 (R76Q, V83I, T84I)

GCQ HSRIGII RQRRAR

1:1

4.7 ± 2.6

1.6 ± 0.1 × 10⁴

0.071 ± 0.037

Vpr^75-90 (R76Q, V83I, R80A, T84I)

GCQ HSA IGII RQRRAR

1:1

2.7 ± 1.9

4.2 ± 0.8 × 10⁴

0.095 ± 0.061

Vpr^75-90 (R80A)

GCRHSA IGVTRQRRAR

1:1

7.5 ± 2.6

3.8 ± 0.6 × 10³

0.027 ± 0.005

Vpr^69-78

FIHFRIGCRH

*

Vpr^75-84

GCRHSRIGVT

*

Vpr^81-90

IGVTRQRRAR

*

Vpr^87-96

RRARNGASRS

*

Vpr^1-96 (918 RU CypA)

BA

ka₁ = 1.3 ± 1.0 × 10⁴

ka₂ = 5.9 ± 1.7 × 10^-6

kd₁ = 1.8 ± 0.2 × 10^-3

kd₂ = 6.7 ± 3.8 × 10^-4

Vpr^1-96 (918 RU CypA)

1:1

0.31 ± 0.28

3.2 ± 1.2 × 10⁴

0.007 ± 0.005

Vpr^1-96 (180 RU CypA)

BA

ka₁ = 5.8 ± 0.8 × 10³

ka₂ = 1.6 ± 1.6 × 10^-4

kd₁ = 0.022 ± 0.025

kd₂ = 7.3 ± 4.0 × 10^-4

Vpr^1-96 (180 RU CypA)

1:1

0.32 ± 0.14

1.6 ± 0.6 × 10⁴

4.22 ± 0.4 × 10^-3