Table 1.

KDs for PDGF-BB interactions with FN domains derived from ka and kd

	PDGF-BB ka (m−1 s−1)	PDGF-BB kd (s−1)	PDGF-BB KD (nm)1	EGF KD (nm)
FN70	NBB2	NBB	NBB	NBB
rFNIII1–113	3.0 × 105	2.8 × 10−2	93	NBB
rFNIII1–7	5.1 × 105	4.2 × 10−2	82	NBB
rFNIII1–2	7.6 × 105	8.2 × 10−2	108	NBB
rFNIII1	3.5 × 105	3.6 × 10−2	103	NBB
FNIII2–114 (FN120)	NBB	NBB	NBB	NBB
rFNIII3–6	NBB	NBB	NBB	NBB
rFNIII8–11	NBB	NBB	NBB	NBB
rFNIII 12–V155	8.0 × 105	2.3 × 10−2	29	NBB
rFNIII12–15	4.5 × 105	1.2 × 10−2	27	NBB
rFNIII12–14	5.6 × 105	2.7 × 10−2	48	NBB
rFNIII13–14	4.5 × 104	4.1 × 10−4	9	NBB
rV5	2.9 × 105	4.1 × 10−2	141	NBB

Abbreviations: FN, fibronectin; rFNIII, recombinant fibronectin type III repeat; ka, kinetic association constant; kd, kinetic dissociation constant; KD, dissociation constant; PDGF-BB, platelet-derived growth factor-BB

¹KD (nm) derived from surface plasmon resonance determinations.

²NBB, no binding observed as determined by surface plasmon resonance determinations.

³rFNIII, recombinant FN domain produced as previously described (Wang et al., 2005).

⁴FNIII_2–11 by QStar pulsar I quadrupole time-of-flight mass spectroscopy sequence identification of FN120 fragment.

⁵rFNIII_12–V15, recombinant FN domain in which the variable domain (V) contains 120 residues.

PDGF-BB binding for FN and rFNIII_8–V15 could not be determined secondary to high noise.