PMID: 13048Feb 1, 1977

Stability of mammalian lens phosphofructokinase

Investigative Ophthalmology & Visual Science
H M ChengE C Barañano


Two interconvertible phosphofructokinase (PFK) forms were found in rat and human lenses; whereas only one predominant form was found in calf lens. PFK isolated from these lenses possessed a common property, i.e., pH-dependent cold (or acid) lability. The inactivation was prevented by including either adenosine triphosphate (ATP) or fructose-6-phosphate (fru-6-P) in the incubating media. The protective effect of ATP or fru-6-P was complete in rat or calf lenses. In human lens, although fru-6-P was fully protective, ATP protected only partially. The inactivation could be reversed by addition of fru-6-P, but not ATP, to the incubating media at 37.5 degrees C. Lens organ culture studies showed that the depletion of lenticular ATP seemed to precipitate the loss of PFK.

Related Concepts

Adenosine Triphosphate, Chromium Ammonium Salt
Bos indicus
Cold Temperature
Drug Stability
Enzyme Activation
Enzyme Reactivators
Hydrogen-Ion Concentration
Lens, Crystalline
Organ Culture Techniques

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