PARTIAL PURIFICATION AND PROPERTIES OF L-GLUTAMINE: D-FRUCTOSE 6-P AMIDOTRANSFERASE FROM HUMAN PLACENTA
نویسندگان: ثبت نشده
چکیده مقاله:
The first enzyme of the pathway for uridine diphosphate N-acetyl-D-glucosamine (UDPAG) biosynthesis i.e. L-glutamine: D-fructose 6-P amidotransferase (E.C. 2.6.1.16) was purified 52-fold from human placenta using methanol fractionation and column chromatography on DEAE-Sephadex A-50. The enzyme showed optimal activity in a broad range of pH from 5.8 to 7.8 in both phosphate and cacodylate buffers. Its K m value for D-fructose 6-P was found to be 2.14 mM. The enzyme was inhibited up to 76% in the presence of 0.12mM UDPAG. A K value of 6.6 ?M was obtained for the feedback inhibition of this enzyme by UDPAG
منابع مشابه
partial purification and properties of l-glutamine: d-fructose 6-p amidotransferase from human placenta
the first enzyme of the pathway for uridine diphosphate n-acetyl-d-glucosamine (udpag) biosynthesis i.e. l-glutamine: d-fructose 6-p amidotransferase (e.c. 2.6.1.16) was purified 52-fold from human placenta using methanol fractionation and column chromatography on deae-sephadex a-50. the enzyme showed optimal activity in a broad range of ph from 5.8 to 7.8 in both phosphate and cacodylate buffe...
متن کاملPartial Purification and Properties of l-Glutamine d-Fructose 6-Phosphate Amidotransferase from Phaseolus aureus.
l-Glutamine d-fructose 6-phosphate amidotransferase (EC 2.6.1.16) was extracted and purified 600-fold by acetone fractionation and diethylaminoethyl cellulose column chromatography from mung bean seeds (Phaseolus aureus). The partially purified enzyme was highly specific for l-glutamine as an amide nitrogen donor, and l-asparagine could not replace it. The enzyme showed a pH optimum in the rang...
متن کاملFeedback inhibition of L-glutamine D-fructose 6-phosphate amidotransferase by uridine diphosphate N-acetylglucosamine in Neurospora crassa.
The enzyme, l-glutamine d-fructose 6-phosphate amidotransferase (EC 2.6.1.16) of Neurospora crassa, which catalyzes the formation of glucosamine 6-phosphate was shown to be subject to feedback inhibition by uridine diphosphate N-acetyl-d-glucosamine (UDP-GlcNAc). The conclusion is based on the following observations. UDP-GlcNAc, the direct precursor of chitin, did not accumulate in the cell eve...
متن کاملFructose 1,6 Bisphosphate Aldolase from Gestational Diabetic Human Placenta: Purification, Identification, and Investigation of Kinetic Properties
Gestational diabetes mellitus is described as glucose intolerance at various degrees that is first detected during pregnancy. In diabetic complications, there are changes in placental function, particularly with respect to intake, transmit, and utilization of glucose, and also in glycolysis and glycolytic enzymes. The placenta possibly plays a critical role in protecting the fetus from adverse ...
متن کاملKinetic characterization of human glutamine-fructose-6-phosphate amidotransferase I: potent feedback inhibition by glucosamine 6-phosphate.
Glutamine-fructose-6-phosphate amidotransferase (GFAT) catalyzes the first committed step in the pathway for biosynthesis of hexosamines in mammals. A member of the N-terminal nucleophile class of amidotransferases, GFAT transfers the amino group from the L-glutamine amide to D-fructose 6-phosphate, producing glutamic acid and glucosamine 6-phosphate. The kinetic constants reported previously f...
متن کاملPartial purification, characterization and properties of two isoforms of glutamine synthetase from Pennisetum glaucum L. leaves.
Two isozymes of glutamine synthetase GS1 and GS2 were partially purified from Pennisetum glaucum leaves by ion-exchange and gel filtration chromatography and their kinetic and regulatory properties were studied using semisynthetase assay of GS. Mg2+ was the most effective cation for activity of both the isozymes; however, it could be efficiently replaced by Co2+. The pH optima for GS1 and GS2 w...
متن کاملمنابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ذخیره در منابع من قبلا به منابع من ذحیره شده{@ msg_add @}
عنوان ژورنال
دوره 3 شماره 1
صفحات -
تاریخ انتشار 1992-06-01
با دنبال کردن یک ژورنال هنگامی که شماره جدید این ژورنال منتشر می شود به شما از طریق ایمیل اطلاع داده می شود.
میزبانی شده توسط پلتفرم ابری doprax.com
copyright © 2015-2023