A Mechanism of Bacterial Interference in vitro

Abstract

A strain of coagulase-negative Staphylococcus (strain W) inhibited the growth of a coagulase-positive Staphylococcus (strain 502A) when both were growing in liquid medium. Inhibition of growth was abolished by the addition of nicotinamide.Bacteria-free filtrates of cultures of strain W failed to fully support the growth of strain 502A or the growth of several other Gram-positive bacteria. Addition of small amounts of nicotinamide or boiling restored the capacity of the filtrates to support growth.It is postulated that the growth of strain W results in the production of an inhibitor which interferes with the metabolism of nicotinamide.