CONVERSION OF AMMONIA OR UREA INTO ESSENTIAL AMINO-ACIDS, L-LEUCINE, L-VALINE, AND L-ISOLEUCINE USING ARTIFICIAL CELLS CONTAINING AN IMMOBILIZED MULTIENZYME SYSTEM AND DEXTRAN-NAD+ - L-LACTIC DEHYDROGENASE FOR COENZYME RECYCLING

被引：4

作者：

GU, KF ^{[1
]}

CHANG, TMS ^{[1
]}

机构：

[1] MCGILL UNIV,FAC MED,ARTIFICIAL CELLS & ORGANS RES CTR,3655 DRUMMOND ST,MONTREAL H3G 1Y6,QUEBEC,CANADA

来源：

APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY | 1990年 / 26卷 / 02期

关键词：

ammonia; Artificial cells; coenzyme recycling; dextran-NAD[!sup]+[!/sup; essential amino acids; immobilization; L-isoleucine; L-lactic dehydrogenase; L-leucine; L-valine; leucine dehydrogenase; microencapsulation; multienzyme system; urea;

D O I：

10.1007/BF02921527

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

A multienzyme system consisting of leucine dehydrogenase (EC 1.4.1.9), L-lactic dehydrogenase (EC 1.1.1.27), urease (EC 3.5.1.5), and dextran-NAD+ was microencapsulated within artificial cells. This system could convert ammonia and urea into essential amino acids, L-leucine, L-valine, and L-isoleucine. L-lactate acted as a cosubstrate for the regeneration of dextran-NADH. Greater concentrations of L-lactate favored the higher conversion ratios. The effects of ammonium salts and urea on reaction rate were also studied. The relative reaction rates in ammonium salts solutions were 44.6-78.8% of those in urea solutions. More than 90% of the original activity was retained when artificial cells were kept at 4°C for 6 wk. © 1990 Humana Press Inc.

引用

页码：115 / 124

页数：10