Glycolate oxidase inhibitors

Some discrimination in the use of glycolate oxidase inhibitors would be expected between C3 and C4 plants. In the latter, it is generally assumed that there is little or no photorespiratory carbon flow. Zelitch noted clear differences between glycolate accumulation in C3 plants such as tobacco and sunflower and C4 maize, with a-HPMS. " Jenkins et al studied the effects of HBA on a C3 barleyand a C4 maize.In both species, photosynthetic carbon dioxide incorporation was diminished, but much more so in barley. Glycolate accumulation accounted for 50-80% of incorporation in barley, in contrast to only 15% in maize. 

The ingestion of ethylene glycol (antifreeze), iron tablets, monoamine oxidase inhibitors used for depressive disorders (eg, phenelzine), or verapamil can result in metabolic acidosis, with an increase in anion gap. The answer is (E),... 

Another type of inhibitor was devised by Kerr on the basis of work by Walsh et on an inhibitor of an FMN enzyme. This compound, L-2-hydroxy-3-butynoic acid (HBA), and its methyl ester caused the rapid accumulation of glycolate and an inhibition of glycolate oxidase in pea leaf disks. 

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