Evolution of a Catabolic Pathway in Bacteria

Science  04 Dec 1964:
Vol. 146, Issue 3649, pp. 1313-1315
DOI: 10.1126/science.146.3649.1313


Genetic derepression of ribitol dehydrogenase in a mutant of Aerobacter aerogenes, strain 1033, enabled it to grow on xylitol, a substrate of the enzyme, but not its inducer. A derivative strain with an improved rate of growth on xylitol was obtained from the first mutant. The faster growth rate was made possible by the production of an altered ribitol dehydrogenase, as demonstrated by an increase in its activity on xylitol relative to ribitol and by its decreased heat stability.