inhibition of peptide binding by na+ was observed in the presence and absence of divalent cations and was strictly additive to inhibition by the poorly hydrolyzable gtp analogue , guanosine-5'-o- ( 3-thiotriphosphate ) , or to adp ribosylation of g-proteins by pertussis toxin .
C0018353
gtp
C0079469
guanosine-5