Adaptation of Lactococcus lactis to its environment: a genomics approach

This thesis describes a number of strategies of Lactococcus lactis to adapt to its ever-changing environment. Although the complete genome sequence of L. lactis subspecies lactis IL1403, became available when this research was started, the genome sequence of the lactic acid bacterial paradigm, L. lactis subspecies cremoris MG1363 had not been determined. This prompted us to sequence the chromosome of the latter strain in order to perform comparative genomics with other bacterial genome sequences. Additionally, the genome sequence would allow making DNA microarrays and to perform transcriptomics studies to determine the topology of global regulatory networks in L. lactis. The intertwinement of the regulatory networks uncovered in this research and in other work is discussed here. The knowledge obtained from L. lactis as the prototype of the lactic acid bacteria (LAB) can be applied to other LAB and will further broaden as well as deepen the knowledge about the life of dairy bacteria.