This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Josephson, B. L. Articles by Fraenkel, D. G. Search for Related Content PubMed PubMed Citation Articles by Josephson, B. L. Articles by Fraenkel, D. G.

 Previous Article  |  Next Article 

J Bacteriol. 1974 June; 118(3): 1082-1089
Copyright © 1974 American Society for Microbiology. All Rights Reserved.

Sugar Metabolism in Transketolase Mutants of Escherichia coli

^a Department of Microbiology and Molecular Genetics, Harvard Medical School, Boston, Massachusetts 02115

ABSTRACT

This paper continues the description of transketolase mutants of Escherichia coli; they are absolutely unable to grow on pentoses, but slightly "leaky" with respect to their aromatic requirement (B. L. Josephson and D. G. Fraenkel, 1969). Several experiments have explored the degree of leakiness and shown it to be low. There is little conversion of radioactive xylose to carbon dioxide. The labeling of ribose in cells grown on [1-¹⁴C]glucose and [2-¹⁴C]glucose accords with its origin being chiefly by the oxidative pathway. A mutant lacking both transketolase and gluconate-6-phosphate dehydrogenase has been constructed; it requires supplementation with pentose. Pentoses are inhibitory to growth of transketolase mutants, but high levels of pentose phosphates do not accumulate in this situation. Several experimental results are suggestive of regulation of metabolic flow in the oxidative branch of the hexose monophosphate shunt.

¹ Present address: Department of Biology, Bard College, Annandale on Hudson, N.Y. 12504.

This article has been cited by other articles:

• Ikeda, M., Katsumata, R. (1999). Hyperproduction of Tryptophan by Corynebacterium glutamicum with the Modified Pentose Phosphate Pathway. Appl. Environ. Microbiol. 65: 2497-2502 [Abstract] [Full Text]  
• Benov, L., Fridovich, I. (1999). Why Superoxide Imposes an Aromatic Amino Acid Auxotrophy on Escherichia coli. THE TRANSKETOLASE CONNECTION. J. Biol. Chem. 274: 4202-4206 [Abstract] [Full Text]