TABLE 3.

Identification of critical residues for the Tollip CUE domain-ubiquitin interaction

SPR-derived binding affinities of Tollip CUE domain for ubiquitin and their corresponding mutants designed based on HSQC titration analyses.

Protein	Construct	KD	Fit	-Fold
		m	χ2
Ubiquitin	Wild-type	1.35 × 10−6	3.06	1
Ubiquitin	L8A	2.00 × 10−6	4.53	1
Ubiquitin	I44A	5.80 × 10−5	1.33	43
Ubiquitin	K63A	3.10 × 10−6	1.07	2
Ubiquitin	H68A	2.00 × 10−6	2.00	1
Ubiquitin	L69A	3.80 × 10−6	0.62	3
Tollip CUE	D239A	2.52 × 10−5	0.24	19
Tollip CUE	M240A	9.33 × 10−5	0.09	69
Tollip CUE	F241A	1.05 × 10−6	3.60	<1
Tollip CUE	N243A	1.16 × 10−5	0.12	9
Tollip CUE	G271V	7.11 × 10−5	0.56	53
Tollip CUE	D239A/M240A/N243A	1.05 × 10−4	2.06	78