Lack of end-product inhibition and repression of leucine synthesis in a strain of Salmonella typhimurium.

Mutants of Salmonella have been isolated which luck either end product inhibition or repression of leucine biosynthesis. In a minimal saltsglucose medium, growth is not impaired by the lack of either control mechanism alone. The loss of both control mechanisms, however, leads to a 43 percent reduction in cell yield and a 1.5-fold reduction in the growth rate.