title: Isolation, characterization and mapping of pyrimidine auxotrophs of Phycomyces blakesleeanus.
abstract: A total of seven pyrimidine auxotrophs of Phycomyces were isolated from among 5-fluoroorotate acid (5-FOA)-resistant mutants. They were classified by complementation into two groups. A representative mutant strain belonging to one group was deficient in orotate phosphoribosyl transferase (OPRTase; EC 2.4.2.10) activity; the mutant strain belonging to the second group was deficient in orotidine-5'-monophosphate decarboxylase (OMPdecase; EC 4.1.1.23). These mutants are defective in the genes pyrF and pyrG respectively. The results from random spore analysis, tetrad analysis, and gene-centromere distances showed that these two markers are located in linkage group VI, with pyrG being a proximal marker and pyrF a distal one.
authors.affiliation: Departamento de Microbiología y Genética, Facultad de Biología, Universidad de Salamanca, Spain.
authors.forename: V
authors.initials: V
authors.lastname: Campuzano
authors.forename: P
authors.initials: P
authors.lastname: del Valle
authors.forename: J I
authors.initials: JI
authors.lastname: de Vicente
authors.forename: A P
authors.initials: AP
authors.lastname: Eslava
authors.forename: M I
authors.initials: MI
authors.lastname: Alvarez
mesh_terms: D002474:Cell-Free System; D004352:Drug Resistance, Microbial; D005816:Genetic Complementation Test; D008040:Genetic Linkage; D005819:Genetic Markers; D005838:Genotype; D009962:Orotate Phosphoribosyltransferase / Q000235:genetics*; D009963:Orotic Acid / Q000031:analogs & derivatives / Q000633:toxicity; D010800:Phycomyces / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D011743:Pyrimidines / Q000378:metabolism*; D011995:Recombination, Genetic; D015183:Restriction Mapping; D013172:Spores, Fungal / Q000378:metabolism
chemical_list: D005819:Genetic Markers; D011743:Pyrimidines; D009963:Orotic Acid; C001242:5-fluoroorotic acid; D009962:Orotate Phosphoribosyltransferase