Summary
Revertants of an acu-6 mutant of Neurospora crassa have been isolated. One revertant, which showed temperature-sensitive growth on acetate (Fig. 2), was found to possess an abnormally thermolabile PEP carboxykinase (Fig. 3). The temperature-sensitive property mapped at, or extremely close to, the site of the original mutation, confirming that acu-6 is the structural gene for PEP carboxykinase.
A group of acu-6 mutants were examined by polyacrylamide gel electrophoresis for the presence of a protein migrating in the same position as PEP carboxykinase. Two of the seven mutants examined were found to possess such protein and both of these show inter-allelic complementation. When grown on acetate the complementing heterokaryons showed about 5% of the wild type level of PEP carboxykinase activity. This activity was more thermolabile than that in wild type (Fig. 6) and the heterokaryons showed temperature-sensitive growth on acetate (Fig. 5).
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Beever, R.E.: Genetic and biochemical studies of PEP carboxykinase in Neurospora crassa. Ph. D. thesis, University of Leeds (1972)
Beever, R.E.: PEP carboxykinase from Neurospora crassa: partial purification and some properties. In preparation (1973a)
Beever, R.E.: Regulation of PEP carboxykinase and isocitrate lyase synthesis in Neurospora crassa. In preparation (1973b)
Coddington, A., Fincham, J.R.S.: Proof of hybrid enzyme formation in a case of inter-allelic complementation in Neurospora crassa. J. molec. Biol. 12, 152–161 (1965)
Crick, F.H.C., Orgel, L.E.: The theory of inter-allelic complementation. J. molec. Biol. 8, 161–165 (1964)
Dixon, G.H., Kornberg, H.L.: Assay methods for key enzymes of the glyoxylate cycle. Biochem. J. 72, 3P (1959)
Fincham, J.R.S.: Genetic complementation. New York: Benjamin 1966
Flavell, R.B., Fincham, J.R.S.: Acetate-nonutilizing mutants of Neurospora crassa. I. Mutant isolation, complementation studies, and linkage relationships. J. Bact. 95, 1056–1062 (1968a)
Flavell, R.B., Fincham, J.R.S.: Acetate-nonutilizing mutants of Neurospora crassa. II. Biochemical deficiencies and the roles of certain enzymes. J. Bact. 95, 1063–1068 (1968b)
Leckie, B.J., Fincham, J.R.S.: A structural gene for Neurospora crassa isocitrate lyase. J. gen. Microbiol. 65, 35–43 (1971)
Racker, E.: Spectrophotometric measurements of the enzymatic formation of fumaric and cis-aconitic acids. Biochim. biophys. Acta (Amst) 4 211–214 (1950)
Ryan, F.J., Beadle, G.W., Tatum, E.L.: The tube method of measuring the growth rate of Neurospora. Amer. J. Bot. 30, 784–799 (1943)
Schlesinger, M.J., Levinthal, C.: Hybrid protein formation of E. coli alkaline phosphatase leading to in vitro complementation. J. molec. Biol. 7, 1–12 (1963)
Sundaram, T.K., Fincham, J.R.S.: Nature of the complementation products formed by a complementing mutant of Neurospora crassa. J. Bact. 95, 787–792 (1968)
Vogel, H.J.: Distribution of lysine pathways among fungi: evolutionary implications. Amer. Naturalist 98, 435–446 (1964)
Westergaard, M., Mitchell, H.K.: Neurospora. V. A synthetic medium favouring sexual reproduction. Amer, J. Bot. 34, 573–577 (1947)
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Beever, R.E., Fincham, J.R.S. Acetate-nonutilizing mutants of Neurospora crassa: acu-6, the structural gene for PEP carboxykinase and inter-allelic complementation at the acu-6 locus. Molec. Gen. Genet. 126, 217–226 (1973). https://doi.org/10.1007/BF00267532
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DOI: https://doi.org/10.1007/BF00267532