Aurintricarboxylic acid is a potent inhibitor of phosphofructokinase

Abstract

Aurintricarboxylic acid (ATA) was found to be a very potent inhibitor of purified rabbit liver phosphofructokinase (PFK), giving 50% inhibition at 0.2 microM. The inhibition was in a manner consistent with interaction at the citrate-inhibitory site of the enzyme. The data suggest that inhibition of PFK by ATA was not due to denaturation of the enzyme or the irreversible binding of inhibitor, since the inhibition could be reversed by addition of allosteric activators of PFK, i.e. fructose 2,6-bisphosphate or AMP. Two other tricarboxylic acids, agaric acid and (-)-hydroxycitrate, were found to inhibit PFK. ATA at much higher concentrations (500 microM) was shown to inhibit fatty acid synthesis from endogenous glycogen in rat hepatocytes; however, protein synthesis was not altered.

Capillary electrophoresis-based assay of phosphofructokinase-1

“…This value is higher than the IC 50 reported by McCune et al [33]. The rabbit muscle isozyme was used in the work presented in this paper, while McCune et al used the rabbit liver isozyme [33]. Moreover, the value reported by McCune et al [33] was measured at pH 7.3, while the current study was conducted at pH 8.0.…”

“…After fitting the data by non-linear regression to Equation 1, the IC 50 was determined to be 3.9 2 ± 0.35 μM. This value is higher than the IC 50 reported by McCune et al [33]. The rabbit muscle isozyme was used in the work presented in this paper, while McCune et al used the rabbit liver isozyme [33].…”

“…The ability of the CE assay to detect inhibition of PFK-1 was demonstrated using a known inhibitor of the enzyme, aurintricarboxylic acid (ATA) [33]. Aurintricarboxylic acid is a reversible inhibitor of PFK-1 and was reported to have an IC 50 of 0.2 μM for rabbit liver PFK-1 [33].…”

“…Aurintricarboxylic acid is a reversible inhibitor of PFK-1 and was reported to have an IC 50 of 0.2 μM for rabbit liver PFK-1 [33]. Electropherograms presented in Supplemental Material (Figure S4) show the elution of ATP and ADP before addition of PFK-1 (A) and at 30 s (B), 8 min (C) and 16 min (D) after addition of PFK-1 with 100 μM ATA present in the reaction buffer.…”

Antiapoptotic Effect of Aurintricarboxylic Acid; Extracellular Action versus Inhibition of Cytosolic Protein Tyrosine Phosphatases

“…[3][4][5][6][7][8][9][10] ATA is also known to inhibit enzymes that do not bind to nucleic acids, such as Phe:tRNA ligase, aminopropyltransferase, phosphofructokinase and several enzymes required by NAD(H)/NADP(H). [11][12][13][14] More recently, a study conducted by our group as well as a study conducted by Liang et al reported that ATA inhibits protein tyrosine phosphatases (PTPs). 15,16 ATA has also been shown to prevent apoptotic cell death in a variety of cell types including breast cancer MDA-231 and MCF-7 cells, macrophage RAW 264.7 cells and rat pheochromocytoma PC12 cells.…”