The Genetics of Microbial Starters

The main bacterial species used in meat fermentation are lactic acid bacteria and coagulase-negative staphylococci. Genetic studies have provided basic knowledge on their metabolic activities and their fitness in meat products. The genome sequences of several starter strains have confirmed their role in the development of the sensorial properties of fermented sausages but have also revealed the main functions characterizing their resistance to stressful environmental conditions encountered during sausage manufacturing. Comparative genomics studies have allowed estimation of the core genomes and the flexible gene pools within the main species. Plasmid sequences from different lactic acid bacteria are available and reveal that some technological traits are associated to plasmidic genes. Appropriate genetic tools for molecular genetic analyses have also been developed, allowing the exchange of chromosomal genes or plasmids. Post-genomic studies using different approaches such as proteomics and transcriptomics have revealed the potentialities of the main starter cultures.