Bush K, Henry P R, Souser-Woehleke M, Trejo W H, Slusarchyk D S
J Antibiot (Tokyo). 1984 Nov;37(11):1308-12. doi: 10.7164/antibiotics.37.1308.
Phanacein, 3,6-dihydroxy-1-phenazinecarboxylic acid, was a specific angiotensin-converting enzyme (ACE) inhibitor isolated from a member of the Streptomyces tanashiensis-zaomyceticus group. Phenacein acted as a pure competitive inhibitor with a Ki of 0.58 microM. ACE inhibition could be reversed by Zn++, but not by Co++, Ca++, or Mg++; therefore, phenacein may chelate the active site zinc of ACE. However, other zinc-containing enzymes were not inhibited at high phenacein concentrations. Phenacein exhibited weak activity against Gram-positive bacteria, but was not active against Candida sp. or Gram-negative organisms.
