Fig. 5.

Identified mutations in the genomic DNA sequences of three MUT strains with the highest amino acid secretion. (A) Amino acid substitutions related to the proteolytic system of L. lactis are shown: two mutations F508S (TTT→TCT) and E504G (GAA→GGA) occurred in a gene encoding a peptidase (IPLA838_00548), and one mutation N2K (AAC→AAA) occurred in the oppA gene. (B) Relationship between the amino acid secretion capacity of different strains and the second residue of the OppA amino acid sequence. (C) Identified mutations in the 5′ UTR of the oppA gene, a transition (T→A) and the one nucleotide deletion (ΔG) is indicated with an asterisk (∗).