Table 1 Binding properties of NP_A(lysozyme) determined by isothermal titration calorimetry (ITC).^a

Entry	Host	Guest	FM	K_a (× 10⁴ M⁻¹)	K_rel	−∆G (kcal/mol)	−∆H (kcal/mol)	T∆S (kcal/mol)
1	NP_A(lysozyme)	lysozyme	1a	57.3 ± 2.8	1.00	7.86	24.45 ± 0.39	−16.59
2	NP_A(lysozyme)	lysozyme	1b	47.8 ± 3.4	0.83	7.75	17.60 ± 0.48	−9.85
3	NP_A(lysozyme)	lysozyme	1c	33.0 ± 1.7	0.58	7.53	15.60 ± 0.30	−8.07
4	NP_A(lysozyme)	lysozyme	1d	29.9 ± 1.4	0.52	7.47	13.74 ± 0.21	−6.27
5	NP_A(lysozyme)	lysozyme	1e	32.5 ± 1.6	0.57	7.52	15.11 ± 0.28	−7.59
6	NINP	lysozyme	1a	<0.12 ^b	<0.002	-	-	-
7	NP_A(lysozyme)	lysozyme	none	0.92 ± 0.4	0.016	5.41	2.34 ± 0.75	3.07
8	NP_A(lysozyme)	BSA	1a	2.67 ± 0.7	0.047	6.04	2.23 ± 0.89	3.81
9	NP_A(lysozyme)	HRP	1a	<0.004 ^b	<0.00007	-	-	-
10	NP_A(lysozyme)	α-amylase	1a	<0.001^b	<0.00002	-	-	-
11	NP_A(lysozyme)	Cytc	1a	<0.06 ^b	<0.001	-	-	-
12	NP_A(lysozyme)	chymotrypsin	1a	<0.05 ^b	<0.001	-	-	-
13	NP_A(lysozyme)	OVA	1a	3.24 ± 0.8	0.057	6.15	3.15 ± 0.96	3.00
14	NP_A(lysozyme)	transferrin	1a	<0.04 ^b	<0.0007	-	-	-
15	NP_A(lysozyme)	trypsin	1a	<0.05 ^b	<0.0009	-	-	-

^aNP_A(lysozyme) was prepared using an optimized ratio of [3]/[4]/[5]/[MBAm]/[FM]/[lysozyme] = 50:50:100:100:8:1. Binding constants were determined by triplicate, independent ITC titrations at 298 K in 10 mM HEPES buffer (pH = 7.5), with the relative errors among the runs in the range of 4–7% (typically <5%). The errors shown in the Table are from curve-fitting for representative titrations, with the corresponding titration curves given in the Supplementary Information (Supplementary Fig. 14).
^bThe binding constant could not be determined accurately by ITC due to the weak binding. Because of the weak binding, the titration curve fits poorly and has large uncertainties in the estimated binding constant.

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