Novel N-terminal protein blocking group identified as dimethylproline


THE N-terminal region of Crithidia oncopelti cytochrome c557 could not be characterised by conventional methods because of an apparently blocked ammo function1. To study this feature the N-terminal tryptic peptide was isolated and 220 MHz proton magnetic resonance (PMR) spectroscopy was used to characterise this peptide and its hydrolysis products. We now report the identification of the novel blocking group as dimethylproline.

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PETTIGREW, G., SMITH, G. Novel N-terminal protein blocking group identified as dimethylproline. Nature 265, 661–662 (1977).

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