Gramicidin(s)

Literature References: Polypeptide antibiotic complex first isolated from the mixture tyrothricin along with tyrocidine, q.q.v. from cultures of Bacillus brevis: Dubos, Hotchkiss, J. Exp. Med. 73, 629 (1941); eidem, J. Biol. Chem. 141, 155 (1941). Commercial extraction: Baron, US 2534541 (1950 to Penick). Commercial preparation is a mixture of the four components, gramicidin A, B, C, and D, comprising about 87.5, 7.1, 5.1, 0.3 percent resp: Gross, Witkop, Biochemistry 4, 2495 (1965). Each of the components A, B, and C consist of 2 chains, one with valine in position 1, comprising 80-95% of the component, and the other with isoleucine in position 1. Structure, characterization, and synthesis of the two isoforms of gramicidin A, N-formylvaline and isoleucine: Sarges, Witkop, J. Am. Chem. Soc. 86, 1862 (1964); 87, 2011, 2020 (1965); Bauer et al., Biochemistry 11, 3266 (1972). Structure of gramicidin B: Sarges, Witkop, J. Am. Chem. Soc. 87, 2027 (1965); of gramicidin C: eidem, Biochemistry 4, 2491 (1965). Synthesis of valine-gramicidin B and C: K. Noda, E. Gross in Chemistry and Biology of Peptides, Proc. 3rd Am. Peptide Symp., J. Meienhofer Ed. (Ann Arbor Science Publishers, Michigan, 1972) pp 241-250. Review: Hunter, Schwartz, "Gramicidins" in Antibiotics I, S. Gottlieb, P. Shaw, Eds. (Springer-Verlag, New York, 1967) pp 642-648. Comprehensive description: G. A. Brewer, Anal. Profiles Drug Subs. 8, 179-218 (1979).