The role of the imidazolyl nitrogen atoms of histidine-12 in ribonuclease S.
نویسندگان
چکیده
S-peptide (residues 1--14) analogues in which the active histidine-12 residue is replaced by Npi-methyl-L-histidine, Ntau-methyl-L-histidine and beta-(pyrid-3-yl)-L-alanine were synthesized and tested for their capacity to bind to S-protein and to activate it. The results show that both imidazolyl nitrogen atoms are required for optimal catalytic functioning, Ntau being essential to the catalytic reaction itself, Npi playing a role in keeping the imidazole ring in the correct position.
منابع مشابه
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ورودعنوان ژورنال:
- The Biochemical journal
دوره 163 2 شماره
صفحات -
تاریخ انتشار 1977