A new acetate-requiring mutant strain of Neurospora crassa (ace-9), has been isolated from the double mutant strain cot-1;inl a, by inositol-less death (Lester and Gross 1959. Science 129:572) in Vogel's medium supplemented with 0.3% sodium acetate and 2% sucrose. The mutant grows well on complex medium and on Vogel's medium supplemented with casamino acids, acetate, or acetate plus ethanol. Like ace-2, ace-3 and ace-4 (Okumura and Kuwana 1979. Japan J. Genet. 54:235-244), it shows very weak activity of pyruvate dehydrogenase compelx, but has normal activities of pyruvate carboxylase, pyruvate kinase and glucose-6-phosphate dehydrogenase.
The ace-9 gene maps between nuc-2 and arg-13 on the right arm of the linkage group II (Table 1). Thus the gene sequence near ace-9 is :-pyr-4 - thr-2 -Centromere- arg-5 - nuc-2 - ace-9 - arg-12 - aro-1.
Table 1. Linkage data of ace-9 in the format of Perkins (1959, Genetics 44:1185-1208)
Recombinations
Zygote genotype Parental Total Marker
and combina- Singles Singles Doubles and isolation
recombination tion region region regions percent numbers
percent 1 2 1 and 2 germination
+ + ace-9 95 38 33 1 394 35423
thr-2 arg-5 + 212 1 14 0 53% 27947
10.2 12.2 KG601
+ ace-9 + 51 36 1 0 253 36601
pyr-4 + arg-12 144 14 7 0 63% KG601
19.8 3.2 UM107
+ ace-9 + 15 1 1 0 115 T28-M2
nuc-2 + aro-1 87 1 10 0 76% KG601
1.7 9.6 Y7655