Abstract
Rat lung phosphofructokinase is purified 250-fold to a specific activity of about 10 by using ATP-sepharose affinity chromatography. The enzyme is activated by cyclic AMP, 5'-AMP, ADP, Pi, NH4+ and K+ ions. Depending upon the concentration of these effectors, the enzyme can exist in several interconvertible forms, differing widely in their affinity for fructose-6-P. These activators also overcome the inhibition of the enzyme by ATP and citrate, thus increasing the glycolytic rate in lung during hypoxia. Unlike the enzyme from other sources, the lung phosphofructokinase is not inhibited by cyclic GMP or phosphoenolpyruvate. The enzyme is very sensitive to inactivation by trypsin and this inactivation is completely reversed by assaying the proteolyzed enzyme in presence of its activators.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.