Selection of an interspecific hybrid Escherichia coli K12 1EA in a chemostat on xylitol yielded a stable mutant synthesizing a four-fold amount of ribitol dehydrogenase (EC 1.1.1.56). Subsequent cultivation of the mutant under increased selection pressure resulted in an accumulation of a mutant with 12-fold higher level of ribitol dehydrogenase relative to the parent strain 1EA. A selection during which a UV-mutagenized population of the 1EA mutant was cultivated in a chemostat on xylitol was accompanied by monitoring the activities of ribitol dehydrogenase and D-arabinitol dehydrogenase (EC 1.1.1.11) of two adjacent catabolite operons. A several-fold increase in the activity of the two enzymes was followed by further increase in the activity of ribitol dehydrogenase and a concomitant drop in the activity of D-arabinitol dehydrogenase. The two hyperproducing strains are compared with the parent mutant as to the rate of synthesis of the two dehydrogenases and growth parameters under the conditions of batch cultivation.

See more in PubMed

J Bacteriol. 1968 Aug;96(2):447-56 PubMed

CRC Crit Rev Microbiol. 1978 Sep;6(1):33-51 PubMed

Biochem J. 1974 Sep;141(3):693-700 PubMed

J Bacteriol. 1974 Jul;119(1):162-9 PubMed

J Bacteriol. 1973 Mar;113(3):1404-11 PubMed

J Bacteriol. 1978 May;134(2):492-500 PubMed

Genetics. 1977 Feb;85(2):193-201 PubMed

J Mol Evol. 1977 Apr 29;9(2):181-90 PubMed

J Bacteriol. 1976 Feb;125(2):728-38 PubMed

J Bacteriol. 1974 Jul;119(1):176-82 PubMed

Nature. 1974 Sep 20;251(5472):200-4 PubMed

Biochem J. 1979 Oct 1;183(1):31-42 PubMed

Proc Natl Acad Sci U S A. 1965 Aug;54(2):572-9 PubMed