Endopeptidase‐24.11 and aminopeptidase activity in brain synaptic membranes are jointly responsible for the hydrolysis of cholecystokinin octapeptide (CCK‐8)

FEBS Letters

Turner, Anthony J.¹  Kenny, A.John¹  Matsas, Rebecca¹ 

[1] MRC Membrane Peptidase Research Group, Department of Biochemistry, University of Leeds, Leeds LS2 9JT, England

关键词: Cholecystokinin (CCK-8);    Endopeptidase-24.11;    Aminopeptidase;    Phosphoramidon;    Bestatin;    Pig;    brain;    synaptic membrane;   

DOI  :  10.1016/0014-5793(84)80583-9

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Endopeptidase-24.11 (EC 3.4.24.11) from pig kidney hydrolysed CCK-8 (sulphated) at two distinct sites: Asp-Tyr(SO₃H)-Met-Gly↓Trp-Met-Asp↓PheNH₂. Under initial conditions, the splitting of the Asp⁷-Phe⁸NH₂ bond proceeded 4-times more rapidly than the Gly⁴-Trp⁵ bond. Pig brain striatal synaptic membranes attacked this substrate at the same sites and this activity was inhibited by phosphoramidon. However, other products were detected even in the presence of phosphoramidon. One of these products was identified as free tryptophan. Since their formation was inhibited by bestatin, one or more membrane aminopeptidases is also implicated in the degradation of CCK-8.

【 授权许可】

Unknown