%0 Journal Article %A Stevens, F. J. %A Wu, T. T. %T Growth on d-Lyxose of a Mutant Strain of Escherichia colik12 Using a Novel Isomerase and Enzymes Related to d-Xylose Metabolism %D 1976 %J Microbiology, %V 97 %N 2 %P 257-265 %@ 1465-2080 %R https://doi.org/10.1099/00221287-97-2-257 %I Microbiology Society, %X Summary: Escherichia coli k12 cannot grow on d-lyxose, but a mutant was isolated which can utilize d-lyxose as sole source of carbon and energy for growth. d-Lyxose is transported into the bacteria by the d-xylose permease. The mutant constitutively synthesizes a new isomerase which is not inducible in the parent strain under any of the conditions tested. This enzyme, whose native substrate appears to be d-man-nose, fortuitously converts d-lyxose into d-xylulose. Its structural gene is located at around 85 min on the E. coli genetic map, away from other known isomerase genes. d-Xylulose is subsequently catabolized by the enzymes of the normal d-xylose metabolic pathway. d-Mannose isomerase was partially purified and some of its properties were examined. %U https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-97-2-257