Spermine-binding protein

Masuko, T., Kashiwagi, K., Kuno, T., Nguyen, N. D., Pahk, A. J., Fukuchi, J., Igarashi, K., and Williams, K. (1999). A regulatory domain (R1-R2) in the amino terminus of the N-methyl-D-aspartate receptor Effects of spermine, protons, and ffenprodil, and structural similarity to bacterial leucine/isoleucine/valine binding protein. Mol. Pharmacol. 55, 957-969. 

Apart from amino acids, peptides and proteins, many other metal-binding substances play essential roles in all living cells. Firstly, there are the pteridines (including folic acid) and purines, whose stability constants have been determined (Albert, 1953 Albert and Serjeant, 1960). Riboflavine is most avid in the partly reduced state (Hemmerich, Veeger and Wood, 1965). Spermine 11 A), and the diamines spermidine 11.5) and putrescine 11.6) also compete. 

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