Elongation factor EF-1 alpha from Artemia is specifically labeled at Lys-63 by the guanine nucleotide analog pyridoxal-5'-diphospho-5'-guanosine

We have synthesized the guanine nucleotide analog pyridoxal-5′-diphospho-5′-guanosine. This compound specifically modifies a single lysine residue in elongation factor 1α from Artemia, indicating that this residue is in close contact with the reactive part of the guanine nucleotide analog. This result is discussed in terms of the structure of the nucleotide-binding domain of the factor.