ΦΩΣΦΑΤΑΣΗ ΤΗΣ 1,6-ΔΙΦΩΣΦΟΡΙΚΗΣ ΦΡΟΥΚΤΟΖΗΣ ΚΑΙ ΑΤΡ-ΔΙΦΩΣΦΟΥΔΡΟΛΑΣΗ ΣΤΟΝ ΑΝΘΡΩΠΙΝΟ ΠΛΑΚΟΥΝΤΑ

FRUCTOSE 1,6-BISPHOSPHATASE (FRUCTOSE) HAS BEEN IDENTIFIED IN EXTRACTS OF HUMANTERM PLACENTA UNDER CONDITIONS WHERE THE PLACENTA WAS FROZEN IN LIQUID NITROGEN IMMEDIATELY AFTER DELIVERY . THE ENZYMATIC ACTIVITY 0.03 MMOLES FRU-P2/MIN/G TISSUE WAS FOUND TO HAVE AN ALKALINE PH OPTIMUM AND MW OF 26,000 DALTONS. THE MICHAELS-MENTEN CONSTANT FOR FRU-P2 WAS FOUND TO BE 2,6X10-5M AT PH 7,4 AMP, AS STRONG INHIBITOR OF FRU-P2ASES, INHIBITED THE ACTIVITY WITH A K1 3,3X10-4M AT PH 7,4. THESE RESULTS INDICATE THE PRESENCE OF A PROTELYSED FORM OF FRUCTOSE-1,6-BISPHOSPHATASE IN HUMAN TERM PLACENTA. ATP-DISPHOSPHOHYDROLASE (ATP-DPH) HAS BEEN ALSO IDENTIFIED IN HUMAN TERM PLACENTA ATP-DPH ACTIVITY WAS FOUND TO BE ASSOCIATED WITH A PARTICULATE FRACTION (P37). IT HYDROLYSES ATP TO AMI AND INORGANIC PHOSPHATE THROUGH ADP. THE PH OPTIMUM OF ATP-DPH IS 8,0-8,5. THE ENZYME IS ACTIVATED BY MG2+(IMM) BY NAF OR NAN3 WHILE INHIBITORS OF ATPASES, MYOKINASE ANDALKALINE PHOSPHATASE HAVE NO EFFECT. ATP-DPH DEGRADES ADP THUS PREVENTING PLATELET AGGREGATION AND BLOOD CLOTTING. THE PHYSIOLOGICAL ROLE OF THIS ENZYME WILLBE FURTHER INVESTIGATED WHEN THE ACTIVITY IS SOLUBILIZED AND PURIFIED.

Grantor dc:publisher

University of Ioannina

Year dc:date

1988

Author dc:creator

• Παπαμαρκάκη, Θωμαΐς

• Ανθρώπινος πλακούντας
• Απυράση
• ΑΤΡ-ΔΙΦΩΣΦΟΥΔΡΟΛΑΣΗ
• ΦΩΣΦΑΤΑΣΗ ΤΗΣ 1,6-ΔΙΦΩΣΦΟΡΙΚΗΣ ΦΡΟΥΚΤΟΖΗΣ
• Apyrase
• ATP diphosphohydrolase
• FRUCTOSE-1,6-BISPHOSPHATASE
• HUMAN TERM PLACENTA
• Ιατρική και Επιστήμες Υγείας
• Κλινική Ιατρική
• Medical and Health Sciences
• Clinical Medicine

Language dc:language

gre

Identifier

10.12681/eadd/1112

OAI identifier oai:identifier

oai:10442/1112