Word: pneumococci
(lookup in dictionary)
(lookup stats)
Dates: during 1961-1961
Sort By: most recent first
(reverse)
...breed true. It began, he recalled, with the little-recognized achievement of three Rockefeller Institute scientists, Drs. Oswald Avery, Colin MacLeod and Maclyn McCarty in 1944. They showed that if nucleic acid from the genetic material of one strain of pneumococcus germs was stirred in with a batch of pneumococci of another strain, the second strain picked up the inherited traits of the first, and then, "in enduring continuity," bred true from cell to daughter cell. "The heritance of an acquired characteristic was no longer an unsupported theory," he said. "It had become a reality...
Early penicillins were active mainly against the berry-shaped microbes or cocci, such as streptococci, staphylococci and pneumococci. But they were ineffective against most rod-shaped bacteria. And most of them had two other draw backs: they were so quickly destroyed by digestive acids that they had to be injected directly into the bloodstream, and they were destroyed by the enzyme penicillinase. which is produced by resistant strains of staphylococci...