Skip to main content
. 2002 Oct;76(20):10270–10281. doi: 10.1128/JVI.76.20.10270-10281.2002

TABLE 1.

Summary of apparent kinetic constants for protein binding to model DNA P/Ta

Protein KCl concn (mM) Nitrocellulose filter-binding assayb
Biosensor assayc
Enzyme kinetics assaydKd (nM)
kon (M−1 s−1) (koff/Kd) koff (s−1) t1/2 (min) Kd (nM) Kd (nM) [koff/kon] Rel. Kd
UL42 50 NDe ND ND ND 35.3 2.1 ND
125 ND ND ND ND 150,000 8,770 ND
Pol 50 1.87 × 104 1.55 × 10−3 7.5 83.0 17.1 1.0 44.2
125 If I I (very fast) I 47.7 2.8 ND
Pol/UL42 50 1.27 × 105 8.37 × 10−4 13.8 6.60 9.02 0.5 ND
125 1.16 × 105 8.76 × 10−4 13.2 7.51 30.7 1.8 7.43
a

All kinetic constants are apparent except for those determined by pre-steady-state kinetic analysis.

b

Values for Kd and koff were determined as described in the legends to Fig. 4 and 5, respectively. The values of t1/2 were derived from the equation ln 0.5 = −kt1/2, and the value of kon was determined according to equation 2.

c

All kinetic constants were derived by global fitting of the binding and dissociation curves from five different protein concentrations using the Biaevaluation version 3.0 software. All binding assumed the langmuir model A + B = AB. Rel. Kd, relative or normalized Kd.

d

Derived by active-site titration of enzyme activity on the model P/T under pre-steady-state conditions (Chaudhuri and Parris, unpublished).

e

ND, not done.

f

I, indeterminate.