Role of intestinal brush border membrane aminopeptidase N in dipeptide transport

Abstract

The kinetics of uptake of radioactive label from [U‐14C]Gly, L‐[4,5‐3H]Leu and the dipeptide [14C]Gly—L‐[4,5‐3H]Leu by the brush border membrane vesicles of porcine small intestine have been studied. The effect of aminopeptidase N inhibitors and leucine‐binding protein on accumulation rates has also been tested. Comparison of the kinetic parameters for uptake and hydrolysis of Gly—L‐Leu makes it possible to conclude that the dipeptide transfer includes two conjugated steps, viz., hydrolysis catalysed by aminopeptidase N and transport of the resultant free amino acids by a specific carrier.

The role of feline aminopeptidase N as a receptor for infectious bronchitis virus

“…Aminopeptidase N, also called CD13 in humans [31], is a zinc metalloprotease. It is a 150-kDa glycoprotein with zinc located in its globular region that is believed to be the active enzymatic site playing a major role in the cleaving of peptides [1,2,12,15,33]. APN is expressed on the plasma membranes of granulocytes [2,36], lymphocytes and monocytes [26,30,31,35].…”

Isolation and characterization of cDNA encoding chicken egg yolk aminopeptidase Ey

“…[5,39]. Mammalian intestinal brush-border membrane aminopeptidase N hydrolyzes oligomeric peptides for digestion and transports the resultant free amino acids [2,20,25]. As there are few reports about avian aminopeptidase N, the role of aminopeptidase Ey in egg yolk is uncertain.…”

Interação da toxina Cry1Ac de Bacillus thuringiensis às BBMVs de diferentes ínstares de Chrysodeixis includens (Lepidoptera: Noctuidae)

“…Como no modelo de formação de poros onde ela facilita a remoção proteolítica da hélice α-1 do domínio I da toxina, promovendo a formação de estruturas oligoméricas de toxinas, conhecidas como pré-poros que irão se ligar aos receptores (APN e ALP) se inserindo na membrana e formando poros (PARDO-LÓPEZ et al, 2006;ATSUMI et al, 2008). No modelo de transdução de sinal onde é a caderina que induz a ativação de uma via intracelular que leva a morte da célula (ZHANG et al, 2006) A família das aminopeptidases estão distribuídas em larga escala em organismos procariotos e eucariotos tendo um papel importante na degradação de proteínas durante a digestão, atuando na catalisação da clivagem de aminoácidos localizados na extremidade amino terminal dos peptídeos e proteínas (ANTONOV et al, 1984;PIGOTT;ELLAR, 2007).…”