Word: gram
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...that there must be agents in the soil capable of breaking up almost anything organic, piling up experiments year after year. Dr. Dubos recently told how he isolated from soil bacilli a substance called "gramicidin," which-in experimental animals-kills pneumococci of five kinds, streptococci, diphtheria bacilli, and other "gram-positive" (blue-staining) germs, possibly including the tubercle bacillus (TIME, April...
Others were quick to follow his lead. Last week Drs. Salman A. Waksman and H. Boyd Woodruff reported discovery of agents from soil which kill "gram-negative" (red-staining) germs-such as those of typhoid fever, dysentery and cholera. But scientists are going ahead cautiously. The protective value of both "gram-positive" and "gram-negative" destroyers has yet to be tried on human beings...
This crystalline killer has been named "gramicidin" because its victims all belong to the large class of microbes which take the gentian violet and iodine stain developed by Hans Christian Joachim Gram of Denmark. Gramicidin protects mice against huge doses of virulent pneumococci and all the other blue-staining germs so far tested. Since the tubercle bacillus belongs to this group, it seems almost certain to succumb to gramicidin...
Then Dubos found in soil samples a spore-bearing bacillus which actually kills five kinds of pneumococcus; staphylococcus (the pus germ), streptococcus, the diphtheria bacillus. The killing agent is a non-protein substance which Dr. Dubos has isolated in crystalline form. One hundred-thousandth of a gram* of the stuff is enough to destroy a billion pneumococci in two hours...
...gram...