A strain of microorganism whose nutritional requirements do not exceed those of the corresponding wild-type strain. 
The parent from which an auxotrophic mutant has been derived. Contrast with auxotroph. ... (09 Oct 1997) ... 
(pro´to-trōf) an organism with the same growth factor requirements as the ancestral strain; said of microbial mutants. adj., prototroph´ic., adj.
The wild-type parent from which an auxotrophic mutant has been derived.
Type: Term Pronunciation: prō′tō-trof, -trōf Definitions: 1. A bacterial strain that has the same nutritional requirements as the wild-type strain from which it was derived.
prototroph 1. A microorganism that has the same nutritional requirements as the parent organism. 2. A bacterial strain that has the same nutritional requirements as the wild-type strain from which it was derived. 3. An organism or cell capable of synthesizing all of its metabolites from inorganic material, requiring no organic nutrients.
a microorganism that has the same nutritional requirements as the parent organism. Cf. · an organism or cell capable of synthesizing all its metabolites from inorganic material, requiring no organic nutrients.