Tyrocidine complex is a mixture of cyclic decapeptides originally isolated from B. brevis. It is active against Gram-positive and Gram-negative bacteria. It forms a complex with single- and double-stranded DNA to inhibit RNA synthesis.
Octicidine is derived from phaseolotoxin by the removal of C-terminal dipeptide. It is a transition state analog that irreversibly suppresses ornithine carbamoyltransferase.