Inhibitory effect of L-canavanine and L-Lysine on arginase activity in sheep spleen tissue

L-kanavanin ve L-lizinin koyun dalak doku arginaz aktivitesi üzerine inhibisyon etkisi

Özet

Arginaz (L-arginin amidino hidrolaz; (E.C.3.5.3.1) ure dongusunun son enzimi olup hayvanların karacigerlerindeki L-arginini, ureye L-ornitine hidrolizini katalizeleyen bir enzimdir. Azotun en iyi cozunebilir ve nontoksik formu olan ure olusumuna katkıda bulunarak vucuttan atılmasına yardımcı olur. Arginaz ure sentezindeki vazgecilmez rolunun yanında; poliamin, prolin ve glutamat sentezi icin ornitin uretimini saglayıp, ayrıca immun sistem aktivasyonunda ve tumor biyolojisinde de rol oynadıgı saptanmıstır. Arginaz enzimi en cok karaciger dokusunda bulunmakla beraber; kalp, rumen, iskelet kası, bobrek, bagırsak, beyin, dalak, tiroit bezi, tukuruk bezi, eritrosit, fibrobast, makrofaj, laktasyondaki meme bezi, testis gibi nonureolitik dokularda da bulunmaktadır. Bu calısma ile koyun dalak doku arginazı uzerine L-kanavanin ve L-lizinin inhibisyon etkileri incelenmesi amaclanmıstır. Sonuc olarak, bir L-amino asit olan L-lizin ve guanidin bilesiklerinden L-kanavaninin enzimi non-kompetetif olarak inhibe ettigi goruldu.

Abstract

Arginase (L-arginine amidinohydrolase; (E.C.3.5.3.1) is the last enzyme of urea cycle and it catalyzes the hydrolysis of L-arginine to urea and L-ornithine in livers of animals. It helps to the excretion process of urea from the body, which is the most soluble and non-toxic form of nitrogen. Along with its essential role in urea synthesis, arginase is also found to have important roles in ornithine production for polyamine, proline and glutamate synthesis and in immune system activation. Mostly found in liver tissue, arginase enzyme is also found in non-ureolytic tissues like heart, rumen, skeletal muscle, kidney, intestine, brain, spleen, thyroid gland, salivary gland, erythrocyte, fibroblast, macrophage, mammary gland in lactation, testicle. With this study, it was aimed to assess the inhibitory efects of arginase in sheep spleen tissue on L-canavanine and L-lysine. Consequently, it was observed that L-lysine as a L-amino acid and guanidine compound L-canavanine inhibits enzyme activity non-competitively.