Open AccessAppearance and Properties of l-Sorbose-Utilizing Mutants of Candida albicans Obtained on a Selective Plate
Author(s) -
Guilhem Janbon,
Fred Sherman,
Elena Rustchenko
Publication year - 1999
Publication title -
genetics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.792
H-Index - 246
eISSN - 1943-2631
pISSN - 0016-6731
DOI - 10.1093/genetics/153.2.653
Subject(s) - sorbose , biology , nondisjunction , genetics , mutant , mutagenesis , candida albicans , chromosome , aneuploidy , gene , biochemistry , fructose
This is the first report that adaptive mutagenesis can arise by chromosomal nondisjunction, a phenomenon previously associated exclusively with DNA alterations. We previously uncovered a novel regulatory mechanism in Candida albicans in which the assimilation of an alternative sugar, l-sorbose, was determined by copy number of chromosome 5, such that monosomic strains utilized l-sorbose, whereas disomic strains did not. We present evidence that this formation of monosomy of chromosome 5, which is apparently a result of nondisjunction, appeared with increased frequencies after a selective condition was applied, i.e., by adaptive mutagenesis. The rate of formation of l-sorbose-utilizing mutants per viable cell per day ranged from 10(-6) at the initial time of detection to 10(-2) after 4 days of incubation on the selective plate.