Chromosome polymorphisms close to the cm-ADE1 locus of candida maltosa.
The imperfect yeast Candida maltosa has an ill-defined genetic constitution; it is nominally diploid, but probably highly aneuploid, in nature. We report on polymorphisms specifically affecting those chromosomes which bear the cm-ADE1 gene. This gene encodes phosphoribosylaminoimidazole-succino-carboxamide synthetase, an enzyme in the adenine biosynthetic pathway. By electrophoretic karyotype analysis, three differently sized chromosomes were demonstrated to carry cm-ADE1; the size (but not the number) of these chromosomes was also found to vary, both between strains and during the mitotic growth of a single strain. Four different alleles of cm-ADE1 have been cloned and sequenced from one prototrophic strain. DNA sequence divergence between these different alleles is as high as 8%, with the greatest divergence being found in the upstream region. Mitotic recombination events that led to changes in the karyotype were followed by using cm-ADE1 DNA as an hybridization probe. A recombination hot-spot in the neighbourhood of the gene appears to be responsible for the instability of the chromosomes on which it residues.
Becher
D
D
Fachrichtung Biologie, Ernst-Mortiz-Arndt-Universität Greifswald, Germany.
Schulze
S
S
Kasüske
A
A
Stoll
R
R
Wedler
H
H
Oliver
S G
SG
D000483:Alleles; D000595:Amino Acid Sequence; D001483:Base Sequence; D002175:Candida / Q000235:genetics*; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D008969:Molecular Sequence Data; D010453:Peptide Synthases / Q000235:genetics*; D011110:Polymorphism, Genetic; D016415:Sequence Alignment
D010453:Peptide Synthases; C022379:phosphoribosylaminoimidazole-succinocarboxamide synthetase