Cu(II) and Ni(II) Interactions with the Terminally Blocked Hexapeptide Ac-Leu-Ala-His-Tyr-Asn-Lys-amide Model of Histone H2B (80–85)

Table 1

Chemical shifts of ¹H(𝛿,ppm) of free and Ni(II)-bound -TYTEHA-, in a metal:peptide ratio 1 : 1, at pH^* 9.5.

-LAHYNK-	H𝛼	H𝛽	H𝛾	Others
Ac				1.95
^1Leu	4.22 4.11 (−0.11)^*	4.03	1.44	𝛿-CH3𝛼:0.81, 𝛿-CH3𝛽:0.85
^2Ala	4.19 3.38 (−0.81)^*			CH3:1.20
^3His	4.46 3.86 (−0.60)^*	2.86, 2.92		H2 7.61 7.25 (−0.36)^*
				H5 6.82 6.77 (−0.05)^*
^4Tyr	4.44 4.64 (+0.20)^*	2.86, 2.92	2.14	H2,6 6.97
				H3,5 6.70
^5Asn	4.60 4.60 (0.00)^*	2.61, 2.73
^6Lys	4.16 4.23 (+0.07)^*	1.67, 1.79	1.36	H𝛿:1.61, H𝜀:2.92

^*Underlined the proton chemical shifts of the bound imidazole ring and C_a-H (the chemical shift difference in parenthesis).