prototrophism

Noun

prototrophism (uncountable)

1. Reversion to the growth factor requirements of an ancestral strain.
   • Berrie [ 254 ] found that the incubation temperature of the colon bacillus has an influence on the incidence of the mutations returning to prototrophism and streptomycin independence1962, Nikolaĭ Petrovich Dubinin, Problems of Radiation Genetics, page 275
   • These strains enable recording of reverse mutations from auxotrophism on tryptophan to prototrophism .1992, Soviet Genetics - Volume 28, Issues 1-6, page 173
2. The ability to obtain nourishment from a single source, such as iron, sulfur, or sunlight or to undergo anabolism.
   • Bacteria vary greatly in their food requirements from extreme examples of prototrophism and autotrophism to extreme parasitism.1934, Marcus M. Mason, A Comparison of the Maximum Growth Rate of Various Bacteria Under Optimal Conditions, page 7
   • The segregation of some markers ( as, for instance, a nutritional requirement versus prototrophism ) is evident only after the examination of the clones derived from the single spores, but the allele segregation has in any case occurred before spore formation.1969, Giuseppe Sermonti, Genetics of Antibiotic-producing Microorganisms, page 144