Preliminary Studies on the N-Terminal Amino Acids of Human Plasminogen^[*]

Summary

Human plasminogen has been analyzed for N-terminal amino acids. It was found to have one residue each of lysine and serine per molecule, with the possibility that threonine and glutamic acid may also serve in this role. On conversion to SK-plasmin, serine is lost as a terminal group and leucine appears as a new terminal unit.

^* This investigation was supported in part by a research grant, H-l792, from the National Heart Institute, Public Health Service, and a research grant from the Heart Association of Erie County.

^** Supported by a Senior Research Fellowship (SF-118) from the Public Health Service.

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