Genetics of lycopene cyclization and substrate transfer in β-carotene biosynthesis in Phycomyces

Abstract

The mutations which block lycopene cyclization and those which stop substrate transfer along the carotene pathway are very closely linked in Phycomyces. Simultaneous blocking of both processes commonly results from single exposures to mutagens; and both blockings may be simultaneously removed after a second exposure. The frequencies of different kinds of mutants after treatments with the mutagens N-methyl-N′-nitro-N-nitrosoguanidine and ICR-170, their reversion patterns, and recombination analyses indicate that lycopene cyclization and substrate transfer are governed by separate segments of a single bifunctional gene. © 1980, Cambridge University Press. All rights reserved.