| 释义 |
reˈvertant, a. and n.
[f. revert v. + -ant.]
A. adj.
1. Her. (See quot. 1828.) rare—0.
1688Holme Acad. Armoury ii. 484/2. 1828 Berry Encycl. Her. I, Revertant, or Reverted, that is, flexed and reflexed, or bending in the form of an S; though it is sometimes used for a bending in the manner of a cheveron.
2. Biol. Having reverted to the normal phenotype though of mutant or abnormal ancestry.
1955Genetics XL. 893 Both revertant (adenine-independent, non-purple) and non-revertant (adenineless, purple) components could be separated by conidial platings. 1970Nature 5 Dec. 908/1 Revertant cells selected from this line exhibit many of the properties of untransformed cells..although they retain the SV 40 genome. 1981New Scientist 18 June 744/2 E. coli is so ‘weak’ that it can easily mutate back to its ordinary cousin... These ‘revertant mutants’ quickly take over.
B. n. Biol. A revertant cell, organism, or strain.
1955Genetics XL. 893 Tests of a number of these purple revertants revealed..that they were heterocaryons. 1971Nature 25 June 488/1 By applying selection pressures to cultures of transformed malignant cells it is possible to select so-called revertants—cells which behave in culture as if they were normal. 1974Ibid. 11 Oct. 483/1 Clones obtained on NFM-histidine were either prototrophic or revertants which grew on histidine as sole nitrogen source. |