SUMMARY: The killing of by horse antiserum has features not previously associated with serum bactericidal reactions. The present work showed that lowering the pH from 7.4 to 6.8 abolished the action of antiserum. The bactericidal effect and the degradation of RNA seen when antiserum is added to growing in horse serum, were abolished at pH 6.8 in much the same way as when haem compounds were added to the system. Addition of chloramphenicol, rifampi-cin or puromycin to growing apparently normally in antiserum at pH 6.8 or in antiserum containing haem compounds led to rapid killing of the bacteria and to degradation of their RNA. Addition of these antibiotics to growing in normal serum produced only bacteriostasis and did not induce RNA breakdown. In contrast, nalidixic acid, although inhibiting growth, did not induce rapid killing and RNA breakdown under the same conditions. These findings were unexpected and led to a reassessment of ideas concerning the mechanism of action of specific antiserum on Although iron compounds clearly abolish the bactericidal effects of antiserum, an explanation of the antibacterial action of such antiserum based simply on an interference with bacterial iron supply is no longer sufficient. The process is more complex and must involve other factors.


Article metrics loading...

Loading full text...

Full text loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error