Bacteria use a number of resistance mechanisms to counter the antibacterial challenge, and one of these is the expression of transmembrane protein-based efflux pumps which can pump out antibacterials from within the cells, thus lowering the antibacterial concentration to nonlethal levels. For example, in S. aureus, the NorA pump can pump out the antibacterial alkaloid berberine and ciprofloxaci...

A permanent alternative is to re-site the fresh gas inflow to the back of the absorber where it has always been positioned in the past. With the elimination of the fresh gas flow error, it is found that respirometers placed at the catheter mount and in the circle give almost identical readings with spontaneous respiration. With controlled respiration there is over-reading of the circle respirom...

The antibacterial action of surface-active cations was reported by Hartmann and Kiigi (1928) on the basis of observations made by Doerr. Domagk (1935) gave a detailed description of the bacteriological properties of a very potent member of this group. Notwithstanding the considerable attention which these discoveries aroused, as shown by the number of investigations reported in the literature, ...

Drug resistance of bacterial pathogens is a growing problem that can be addressed through the discovery of compounds with novel mechanisms of antibacterial activity. Natural products, including plant phenolic compounds, are one source of diverse chemical structures that could inhibit bacteria through novel mechanisms. However, evaluating novel antibacterial mechanisms of action can be difficult...

It is generally accepted that the composition of the medium exerts an important influence on the action of antibacterial substances on microorgani. Many workers have succeeded in paralyzing the effect of antibacterials by the addition to the media of substances such as organ extracts, peptone, and bacterial extracts. Thus, Mcllwain (1941) counteracted the antibacterial effect of acriflavin on E...