Transformation of Aspergillus flavus: construction of urate oxidase-deficient mutants by gene disruption.
A transformation procedure based on the complementation of a genetic defect was developed using a nitrate reductase-deficient mutant of Aspergillus flavus. The initial transformation efficiency was improved 40-fold by combining factors in a planned experimental program. Although low, this transformation rate was sufficient to obtain transformants in which the urate oxidase-encoding gene (uaZ) was disrupted in a gene replacement experiment. These new uaZ- strains were unable to utilize uric acid as the unique nitrogen source and could be reversed directly to the wild-type phenotype in second order transformation experiments using a urate oxidase-expressing vector.
Chevalet
L
L
SANOFI-Chimie, Département Développement Biotechnologie, Aramon, France.
Tiraby
G
G
Cabane
B
B
Loison
G
G
D001231:Aspergillus flavus / Q000187:drug effects / Q000201:enzymology / Q000235:genetics*; D015139:Blotting, Southern; D003001:Cloning, Molecular; D005816:Genetic Complementation Test; D009154:Mutation / Q000235:genetics; D050901:Nitrate Reductase; D009565:Nitrate Reductases / Q000235:genetics; D010957:Plasmids / Q000235:genetics; D015183:Restriction Mapping; D014170:Transformation, Genetic / Q000235:genetics*; D014503:Urate Oxidase / Q000235:genetics* / Q000378:metabolism; D014527:Uric Acid / Q000494:pharmacology
D014527:Uric Acid; D009565:Nitrate Reductases; D014503:Urate Oxidase; D050901:Nitrate Reductase