A 80915A is A semi-naphthoquinone antibiotic from Streptomyces aculeolatus. It is a potent inhibitor of gastric (H(+)-K+)-ATPase. Inhibition by A80915A is dependent on the conformation of gastric (H(+)-K+)-ATPase, potassium slows the rate of inhibition by
AK-135 is a derivative of 1,4-naphthoquinone (Menadione). AK-135 has been shown to restore the electron flow in defective respiratory chain (hypoxia or rotenone) systems more effectively than Menadione.
Methylspinazarin is a naphthoquinone bacterial metabolite that has been found in Streptomyces and is an inhibitor of catechol O-methyltransferase (COMT; IC50 = 0.8 μg ml).1 It is selective for COMT over tyrosine hydroxylase, DOPA decarboxylase, and dopamine-β-hydroxylase at 100 μg ml. Methylspinazarin decreases blood pressure in spontaneously hypertensive rats when administered at a dose of 50 mg kg. |1. Chimura, H., Sawa, T., Takita, T., et al. Methylspinazarin and dihydromethylspinazarin, gatechol-O-methyl transerfase inhibitors produced by Streptomyces. J. Antibiot. 26(2), 112-114 (1973).