Dipeptidase membrane-bound

Membrane alanyl aminopeptidase (microsomal aminopeptidase, amino-peptidase M, EC 3.4.11.2) and peptidyl-dipeptidase A (angiotensin I converting enzyme, EC 3.4.15.1) located in the vascular endothelium and smooth muscle cell surface modulate the levels of vasoactive peptides [23], One of the roles of membrane-bound enzymes is to switch off the action of peptides in the vicinity of the target or to prevent them from gaining access to a region containing receptors that are activated only by locally released peptides. 

This zinc-dependent enzyme [EC 3.4.15.1] (also known as dipeptidyl carboxypeptidase I, dipeptidyl-dipeptidase A, kininase II, peptidase P, and carboxycathepsin) catalyzes the release of a C-terminal dipeptide at a neutral pH. The enzyme will also act on bradykinin. The presence of prolyl residues in angiotensin I and in bradykinin results in only single dipeptides being released due to the activity of this enzyme, a protein which belongs to the peptidase M2 family. The enzyme is a glycoprotein, generally membrane-bound, that is chloride ion-dependent. 

Membrane-bound dipeptidase (cysteinyl-glyci-nase) deficiency Kidney, liver, placenta, epithelium and endothelial cells (trachea) 16q24J 179780... 

Fig. 34.1. Metabolic pathway of leukotriene biosynthesis and metabolism including known metabolic defects 34.1, LTC4-synthase 34.2, y-glutamyl transpeptidase 34.3, membrane-bound dipeptidase. LT, leukotriene 5-LOAPy 5-lipoxygenase-activating protein 5-LO, 5-lipoxygenase LTA4Hy leukotriene A4 hydrolase...

LTC4-synthase deficiency 34.2 y-Glutamyl transpeptidase deficiency 34.3 Membrane-bound dipeptidase cystei nylg lyci nas e) deficiency... 

DNA analysis has not been performed yet. It might be in principle possible from genomic DNA (e.g. extracted from blood cells or cultured skin fibroblasts) in 31.1 (LTC4-synthase deficiency) and 34.3 (Membrane-bound dipeptidase deficiency). In 34.2 (y-Glutamyl transpeptidase deficiency) DNA analysis might be difficult since the human genome has at least seven different loco for y-glutamyl-transpeptidase. Five of them are located on chromosome 22. 

Membrane-bound dipeptidase (cysteinyl-glycinase) deficiency 34.3... 

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