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 van der Werf, M. J. Articles by Zeikus, J. G. Search for Related Content PubMed PubMed Citation Articles by van der Werf, M. J. Articles by Zeikus, J. G. Agricola Articles by van der Werf, M. J. Articles by Zeikus, J. G.

 Previous Article  |  Next Article 

Appl. Environ. Microbiol., Oct 1996, 3560-3566, Vol 62, No. 10
Copyright © 1996, American Society for Microbiology

5-Aminolevulinate production by Escherichia coli containing the Rhodobacter sphaeroides hemA gene

MJ van der Werf and JG Zeikus
Department of Biochemistry, Michigan State University, East Lansing, 48824, USA.

The Rhodobacter sphaeroides hemA gene codes for 5-aminolevulinate (ALA) synthase. This enzyme catalyzes the pyridoxal phosphate-dependent condensation of succinyl coenzyme A and glycine-forming ALA. The R. sphaeroides hemA gene in the pUC18/19 vector system was transformed into Escherichia coli. The effects of both genetic and physiological factors on the expression of ALA synthase and the production of ALA were studied. ALA synthase activity levels were maximal when hemA had the same transcription direction as the lac promoter. The distance between the lac promoter and hemA affected the expression of ALA synthase on different growth substrates. The E. coli host strain used had an enormous effect on the ALA synthase activity level and on the production of ALA, with E. coli DH1 being best suited. The ALA synthase activity level was also dependent on the carbon source. Succinate, L- malate, fumarate, and L-aspartate gave the highest levels of ALA synthase activity, while the use of lactose as a carbon source resulted in a repression of ALA synthase. After growth on succinate, ALA synthase represented approximately 5% of total cellular protein. The ALA synthase activity level was also dependent on the pH of the medium, with maximal activity occurring at pH 6.5. ALA production by whole cells was limited by the availability of glycine, and the addition of 2 g of glycine per liter to the growth medium increased the production of ALA fivefold, to 2.25 mM. In recombinant E. coli extracts, up to 22 mM ALA was produced from succinate, glycine, and ATP.

This article has been cited by other articles:

• Kwon, S. J., de Boer, A. L., Petri, R., Schmidt-Dannert, C. (2003). High-Level Production of Porphyrins in Metabolically Engineered Escherichia coli: Systematic Extension of a Pathway Assembled from Overexpressed Genes Involved in Heme Biosynthesis. Appl. Environ. Microbiol. 69: 4875-4883 [Abstract] [Full Text]