The Structure of the “Memory-Code-Word” Scotophobin

  • Wolfgang Parr
  • Gunther Holzer


The tentative structure of scotophobin, a pentadecapeptide amide isolated from brain of rats which had been trained to have a fear of the dark, was confirmed by a synthetic approach. The synthetic material was prepared via the solid phase method and was cleaved from the solid carrier by direct ammonolysis. The purified product showed 100% biological activity and an undistinguishable dose-response-curve as the natural scotophobin. The synthetic peptide and its tryptic fragments showed identical properties by thin layer chromatography. Furthermore, micro-dansylation of the synthetic and natural materials gave the same results. According to these findings scotophobin has the following primary structure: \(\mathop {{\text{Ser}}}\limits_{\text{1}} {\text{ - }}\mathop {{\text{Asp}}}\limits_{\text{2}} {\text{ - }}\mathop {{\text{Asn}}}\limits_{\text{3}} {\text{ - }}\mathop {{\text{Asn}}}\limits_{\text{4}} {\text{ - }}\mathop {{\text{Gln}}}\limits_{\text{5}} {\text{ - }}\mathop {{\text{Gln}}}\limits_{\text{6}} {\text{ - }}\mathop {{\text{Gly}}}\limits_{\text{7}} {\text{ - }}\mathop {{\text{Lys}}}\limits_{\text{8}} {\text{ - }}\mathop {{\text{Ser}}}\limits_{\text{9}} {\text{ - }}\mathop {{\text{Ala}}}\limits_{{\text{10}}} {\text{ - }}\mathop {{\text{Gln}}}\limits_{{\text{11}}} {\text{ - }}\mathop {{\text{Gln}}}\limits_{{\text{12}}} {\text{ - }}\mathop {{\text{Gly}}}\limits_{{\text{13}}} {\text{ - }}\mathop {{\text{Gly}}}\limits_{{\text{14}}} {\text{ - }}\mathop {{\text{TyrN}}{{\text{H}}_{\text{2}}}}\limits_{{\text{15}}} \)


Amino Acid Analysis Butyl Ester Tryptic Fragment Phenyl Ester Brain Peptide 


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Copyright information

© Plenum Press, New York 1973

Authors and Affiliations

  • Wolfgang Parr
    • 1
  • Gunther Holzer
    • 1
  1. 1.Chemistry DepartmentUniversity of HoustonHoustonUSA

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