AEM
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Levander, F.
Right arrow Articles by Rådström, P.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Levander, F.
Right arrow Articles by Rådström, P.
Agricola
Right arrow Articles by Levander, F.
Right arrow Articles by Rådström, P.

Applied and Environmental Microbiology, June 2001, p. 2734-2738, Vol. 67, No. 6
0099-2240/01/$04.00+0   DOI: 10.1128/AEM.67.6.2734-2738.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.

Requirement for Phosphoglucomutase in Exopolysaccharide Biosynthesis in Glucose- and Lactose-Utilizing Streptococcus thermophilus

Fredrik Levander and Peter Rådström*

Applied Microbiology, Center for Chemistry and Chemical Engineering, Lund Institute of Technology, Lund University, SE-221 00 Lund, Sweden

Received 13 November 2000/Accepted 20 March 2001

To study the influence of phosphoglucomutase (PGM) activity on exopolysaccharide (EPS) synthesis in glucose- and lactose-growing Streptococcus thermophilus, a knockout PGM mutant and a strain with elevated PGM activity were constructed. The pgmA gene, encoding PGM in S. thermophilus LY03, was identified and cloned. The gene was functional in Escherichia coli and was shown to be expressed from its own promoter. The pgmA-deficient mutant was unable to grow on glucose, while the mutation did not affect growth on lactose. Overexpression of pgmA had no significant effect on EPS production in glucose-growing cells. Neither deletion nor overexpression of pgmA changed the growth or EPS production on lactose. Thus, the EPS precursors in lactose-utilizing S. thermophilus are most probably formed from the galactose moiety of lactose via the Leloir pathway, which circumvents the need for a functional PGM.

* Corresponding author. Mailing address: Applied Microbiology, Center for Chemistry and Chemical Engineering, Lund Institute of Technology, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden. Phone: 46-46 222 3412. Fax: 46-46 222 4203. E-mail: Peter.Radstrom{at}tmb.lth.se.

Applied and Environmental Microbiology, June 2001, p. 2734-2738, Vol. 67, No. 6
0099-2240/01/$04.00+0   DOI: 10.1128/AEM.67.6.2734-2738.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.


This article has been cited by other articles:



Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
J. Bacteriol. Microbiol. Mol. Biol. Rev. Eukaryot. Cell All ASM Journals

Copyright © 2001 by the American Society for Microbiology. All rights reserved.