Petite Mutants induced in Yeast by Dithranol (1,8,9-trihydroxyanthracene), an Important Therapeutic Agent against Psoriasis

Induction of petite yeast mutants by membrane-active agents.

Ethanol proved to be a strong mutagenic agent of Saccharomyces mitochondrial DNA. Other active membrane solvents, such as tert-butanol, isopropanol, and sodium dodecyl sulfate, also turned out to be powerful petite mutation [rho-] inducers. Mutants defective in ergosterol synthesis (erg mutants) showed an extremely high frequency of spontaneous petite cells, suggesting that mitochondrial membra...

Complementation in cytoplasmic petite mutants of yeast to form respiratory competent cells.

Complementation has been observed in cytoplasmic respiratory deficient yeast cells (petites) to yield respiratory competent diploids. This successful demonstration depended on the use of spontaneous petites of recent origin and on crosses involving all possible apirwise combinations between the many different petite isolates of opposite mating type. The possibility of deletion of a single uniqu...

Petite mutation in yeast. II. Isolation of mutants containing mitochondrial deoxyribonucleic acid of reduced size.

A series of petite mutants of Saccharomyces cerevisiae, generated after treatment for various times with ethidium bromide, was isolated, and the mitochondrial deoxyribonucleic acid size for each member was estimated. It was found that, as the treatment time with ethidium bromide was increased, the mitochondrial deoxyribonucleic acid isolated from the petite series was increasingly reduced in size.

-patient treatment with calcipotriol versus dithranol in refractory psoriasis

Mutants of yeast defective in mutation induced by ultraviolet light.

NDUCED mutations are thought to arise as a result of enzymatic processes uti‘lizing DNA damage as a substrate (BRIDGES 1969). Although the molecular mechanism is not known, evidence reviewed by WITKIN (1969) suggests that in E. coli mutations are produced during postreplication repair of lethal damage induced by ultraviolet light (UV) and controlled by r e d and ezrf (or lexf) genes. Strains ca...