germicidin a

Germicidin A is a pyranone originally derived from S. viridochromogenes that acts as a reversible, autoregulative inhibitor of spore germination and hyphal elongation in the genus Streptomyces at concentrations as low as 200 pM. During germination, spores of Streptomyces excrete germicidin A along with other germicidin homologs, which inhibit germination of its own arthrospores. At higher concentrations, germicidin A can inhibit the porcine Na+/K+-activated ATPase (ID50 = 100 μM) and prevent the germination of the cress L. sativum.

Germicidin C, a microbial metabolite with antibacterial properties, is found in the sponge-like fungus Aspergillus niger. It inhibits the growth of various pathogenic bacteria, such as Staphylococcus aureus and Escherichia coli, with a minimum inhibitory concentration (MIC) ranging from 32-64 µg/mL.