This Article Full Text 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 Vido, K. Articles by Gaudu, P. Search for Related Content PubMed PubMed Citation Articles by Vido, K. Articles by Gaudu, P.

 Previous Article  |  Next Article 

Journal of Bacteriology, March 2004, p. 1648-1657, Vol. 186, No. 6
0021-9193/04/$08.00+0     DOI: 10.1128/JB.186.6.1648-1657.2004
Copyright © 2004, American Society for Microbiology. All Rights Reserved.

Proteome Analyses of Heme-Dependent Respiration in Lactococcus lactis: Involvement of the Proteolytic System

Unité de Recherches Laitières et Génétique Appliquée,¹ Unité de Biochimie et Structure des Protéines, Institut National de la Recherche Agronomique, Domaine de Vilvert, 78352 Jouy en Josas, France²

Received 19 September 2003/ Accepted 4 December 2003

Sugar fermentation was long considered the sole means of energy metabolism available to lactic acid bacteria. We recently showed that metabolism of Lactococcus lactis shifts progressively from fermentation to respiration during growth when oxygen and heme are available. To provide insights into this phenomenon, we compared the proteomic profiles of L. lactis under fermentative and respiratory growth conditions in rich medium. We identified 21 proteins whose levels differed significantly between these conditions. Two major groups of proteins were distinguished, one involved in carbon metabolism and the second in nitrogen metabolism. Unexpectedly, enzymes of the proteolytic system (PepO1 and PepC) which are repressed in rich medium in fermentation growth were induced under respiratory conditions despite the availability of free amino acids. A triple mutant (dtpT dtpP oppA) deficient in oligopeptide transport displayed normal respiration, showing that increased proteolytic activity is not an absolute requirement for respiratory metabolism. Transcriptional analysis confirmed that pepO1 is induced under respiration-permissive conditions. This induction was independent of CodY, the major regulator of proteolytic functions in L. lactis. We also observed that pepO1 induction is redox sensitive. In a codY mutant, pepO1 expression was increased twofold in aeration and eightfold in respiration-permissive conditions compared to static conditions. These observations suggest that new regulators activate proteolysis in L. lactis, which help to maintain the energetic needs of L. lactis during respiration.

This article has been cited by other articles:

• Pedersen, M. B., Garrigues, C., Tuphile, K., Brun, C., Vido, K., Bennedsen, M., Mollgaard, H., Gaudu, P., Gruss, A. (2008). Impact of Aeration and Heme-Activated Respiration on Lactococcus lactis Gene Expression: Identification of a Heme-Responsive Operon. J. Bacteriol. 190: 4903-4911 [Abstract] [Full Text]  
• Brooijmans, R. J. W., Poolman, B., Schuurman-Wolters, G. K., de Vos, W. M., Hugenholtz, J. (2007). Generation of a Membrane Potential by Lactococcus lactis through Aerobic Electron Transport. J. Bacteriol. 189: 5203-5209 [Abstract] [Full Text]  
• Wegmann, U., O'Connell-Motherway, M., Zomer, A., Buist, G., Shearman, C., Canchaya, C., Ventura, M., Goesmann, A., Gasson, M. J., Kuipers, O. P., van Sinderen, D., Kok, J. (2007). Complete Genome Sequence of the Prototype Lactic Acid Bacterium Lactococcus lactis subsp. cremoris MG1363. J. Bacteriol. 189: 3256-3270 [Abstract] [Full Text]  
• Larsen, N., Boye, M., Siegumfeldt, H., Jakobsen, M. (2006). Differential Expression of Proteins and Genes in the Lag Phase of Lactococcus lactis subsp. lactis Grown in Synthetic Medium and Reconstituted Skim Milk. Appl. Environ. Microbiol. 72: 1173-1179 [Abstract] [Full Text]  
• Gitton, C., Meyrand, M., Wang, J., Caron, C., Trubuil, A., Guillot, A., Mistou, M.-Y. (2005). Proteomic Signature of Lactococcus lactis NCDO763 Cultivated in Milk. Appl. Environ. Microbiol. 71: 7152-7163 [Abstract] [Full Text]  
• Vido, K., Diemer, H., Van Dorsselaer, A., Leize, E., Juillard, V., Gruss, A., Gaudu, P. (2005). Roles of Thioredoxin Reductase during the Aerobic Life of Lactococcus lactis. J. Bacteriol. 187: 601-610 [Abstract] [Full Text]