Antibacterial agents

Antibacterial agents

 Antibacterial agents which act against cell metabolism (antimetabolites)
1. Sulphonamides: History : The best example of antibacterial agents acting as antimetabolites are the sulphonamides (sometimes called the sulpha drugs). 
The sulphonamide story began in 1935 when it was discovered that a red dye called prontosil had antibacterial properties in vivo (i.e. when given to laboratory animals).

Strangely enough, no antibacterial effect was observed in vitro. In other words, prontosil could not kill bacteria grown in the test tube. This remained a mystery until it was discovered that prontosil was metabolized by bacteria present in the small intestine of the test animal to give a product called sulphanilamide.


 Sulphanilamide was synthesized in the laboratory and became the first synthetic antibacterial agent found to be active against a wide range of infections. Sulpha drugs have proved ineffective against infection such as Salmonella — the organism responsible for typhoid.                                                              Salmonella