This Article Full Text Full Text (PDF) Other Versions of this Article: AEM.00103-08v1 74/15/4671    most recent 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 Google Scholar Articles by Steen, A. Articles by Kok, J. PubMed PubMed Citation Articles by Steen, A. Articles by Kok, J. Agricola Articles by Steen, A. Articles by Kok, J.

 Previous Article  |  Next Article 

Applied and Environmental Microbiology, August 2008, p. 4671-4679, Vol. 74, No. 15
0099-2240/08/$08.00+0     doi:10.1128/AEM.00103-08
Copyright © 2008, American Society for Microbiology. All Rights Reserved.

Reduced Lysis upon Growth of Lactococcus lactis on Galactose Is a Consequence of Decreased Binding of the Autolysin AcmA

Anton Steen,^, Girbe Buist,^, Naomi E. Kramer, Ruud Jalving, Germaine F. J. D. Benus, Gerard Venema, Oscar P. Kuipers, and Jan Kok^*

Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Kerklaan 30, 9751 NN Haren, The Netherlands

Received 13 January 2008/ Accepted 10 May 2008

When Lactococcus lactis subsp. lactis IL1403 or L. lactis subsp. cremoris MG1363 is grown in a medium with galactose as the carbon source, the culture lyses to a lesser extent in stationary phase than when the bacteria are grown in a medium containing glucose. Expression of AcmA, the major autolysin of L. lactis, is not influenced by the carbon source. Binding studies with a fusion protein consisting of the MSA2 protein of Plasmodium falciparum and the C-terminal peptidoglycan-binding domain of AcmA revealed that cell walls of cells from both subspecies grown on galactose bind less AcmA than cell walls of cells grown on glucose. Cells grown on glucose or galactose and treated with trichloroacetic acid prior to AcmA binding bind similar amounts of AcmA. Analysis of the composition of the lipoteichoic acids (LTAs) of L. lactis IL1403 cells grown on glucose or galactose showed that the LTA composition is influenced by the carbon source: cells grown on galactose contain LTA with less galactose than cells grown on glucose. In conclusion, growth of L. lactis on galactose changes the LTA composition in the cell wall in such a way that less AcmA is able to bind to the peptidoglycan, resulting in a decrease in autolysis.

Published ahead of print on 6 June 2008.

A.S. and G.B. contributed equally to this work.

Present address: Membrane Enzymology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.

Present address: Laboratory of Molecular Bacteriology, Department of Medical Microbiology, University Medical Center Groningen and University of Groningen, Hanzeplein 1, 9700 RB Groningen, The Netherlands.