Studies on the biochemistry of micro-organisms

Abstract

Appendix: Antibacterial activities of geodin and erdin, by Sidonie Marcus. Further degradative studies of geodin and erdin, 2 Cl-containing metabolic products of A. terreus, are descr., leading to definitive structures for the methylation product obtained with dimethyl sulfate and alkali; and for geodin and erdin hydrates, obtained by the action of 80% H2SO4. On the basis of this and other information, possible structural formulae for the 2 metabolic products are presented, and their limitations discussed, the chief difficulties being the point of attachment of a 2d ether link between the rings in a highly substituted 0-benzoylbenzoic acid, and the apparent lack of an asymmetric center in erdin. The optical activity of geodin probably lies in a pseudo-ester group derived from this structure, while the non-chlorinated ring in each substance has semiquinoid rather than phenolic properties. Geodin is regarded as a moderately potent antibiotic substance active, in the main, against Gram-positive bacteria only, while erdin has not been observed to inhibit the growth of bacteria.