A TRANSKETOLASE MUTANT OF CORYNEBACTERIUM-GLUTAMICUM

A transketolase mutant was first isolated from Corynebacterium glutami cum, an organism of industrial importance. The mutant strain exhibited an absolute requirement for shikimic acid or the aromatic amino acids and vitamins for growth, and also failed to grow on ribose or gluconi c acid as sole carbon source, even with the aromatic supplement. All o f these defective properties were fully restored in spontaneous revert ants, indicating the existence of a single transketolase in C. glutami cum that was indispensable both for aromatic biosynthesis and for util ization of these carbohydrates in vivo. The transketolase mutant accum ulated ribulose extracellularly when cultivated in glucose medium with shikimic acid, but no ribose was detected.