Genes correlated to growth on lactose were found on plasmid D of L. lactis SK11. Colours represent strength of relationship between a gene and a phenotype (Figure 1). Phenotypes are either shown as last digits in column names or with suffixes “high” or “low”, where 0 indicates there is no growth and other numbers indicate different growth levels in different experiments as described in the Additional file 1. Here “high” and “low” phenotypes indicate high and low growth levels, respectively. For gene annotations see Additional file 3.