Origin of Copper Resistant Cells
Studies on the Adaptation off Yeast to Copper XV
1956 Volume 69 Issue 822 Pages 560-570
Details
1956 Volume 69 Issue 822 Pages 560-570
1. The substrain, R1b, obtainable by training the parent strain on 1mM copper medium, forms round and smooth brown (viz, the R1b-type) colonies on 1-2mM copper agar. On this medium, the parent strain grows irregular colonies carryin white and brown papillae. The latter papillae contain cells of the R1b-type.
2. Even after serial subcultures in the normal medium, R1b forms the R1b-type colonies on the copper medium. However, a little deadaptation was disclosed when the resistance test was made with higher concentrations of copper.
3. Selective growth of cells of intermediate resistance, as well as of R1b-type, as observed when the parent strain was inoculated in a liquid copper medium.
4. The clonal occurrence of resistance could not be observed in the parent strain.
5. Many of the clones of parent cells spread on 1.2mM copper agar can continue to grow very slowly, older cells losing their budding ability almost as rapidly as new ones are produced. When cells are formed which do not lose the budding ability so soon, the group of such cells grows rapidly and forms a papilla.
