Effect of chain length on the energy gap in radical ... - ACS Publications

Mar 26, 2018 - The absorption spectrum of the one-to-one complex between the truncated zinc finger peptide CP1-C4 and cobalt(II) in 50 mM. HEPES, 50 m...
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J . Am. Chem. SOC.1991, 113, 5451-5453

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Figure 1. The absorption spectrum of the one-to-one complex between the truncated zinc finger peptide CPI-C4 and cobalt(I1) in 50 m M HEPES, 50 mM NaCl buffer, pH 7.0. This spectrum is similar to that for complexes of intact zinc finger peptides although it is slightly broader and somewhat red-shifted due to the replacement of one histidine by a coordinated water. The schematic structure shown is supported by nuclear magnetic resonance studies of the parent CPl-Zn2+ complex.' This and all other experiments were performed under an atmosphere of 95% dinitrogen/5% dihydrogen.

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