Genetically modified Lactobacillus and uses thereof

An expression cassette comprising a promoter for transcriptional expression and at least one heterologous coding region encoding a biomolecule;

• wherein the biomolecule is a bacterial peptide, an enzyme, a lysin, or a single chain antibody and wherein:
• (a) the bacterial peptide is selected from mersacidin-E1 and E-2 molecules comprising sequences of SEQ ID NO:
• 2 and SEQ ID NO:
• 4, or Bacillus bacteriocin comprising a sequence selected from SEQ ID NO:
• 44, SEQ ID NO:
• 45, SEQ ID NO:
• 46, SEQ ID NO:47, and SEQ ID NO:
• 48;
• (b) the enzyme is selected from SEQ ID NO:
• 5 or SEQ ID NO:
• 6;
• (c) the lysin is selected from SEQ ID NO:
• 24, SEQ ID NO:
• 25, SEQ ID NO:
• 26, SEQ ID NO:
• 27, and SEQ ID NO:
• 28;
• or
• (d) the single chain antibody is directed against pathogenic bacterium Clostridium perfringens, specifically recognizes the bacterial protein C. perfringens alpha toxin or C. perfringens NetB toxin, and selected from SEQ ID NO:
• 29, SEQ ID NO:
• 49, SEQ ID NO:
• 30, SEQ ID NO:
• 33, SEQ ID NO:
• 34, and SEQ ID NO:
• 50;
• wherein the promoter comprises the sequence of SEQ ID NO:
• 14, SEQ ID NO:
• 15, SEQ ID NO:
• 16, SEQ ID NO:
• 17, SEQ ID NO:
• 18, SEQ ID NO:
• 19, SEQ ID NO:
• 41, SEQ ID NO:
• 42 or SEQ ID NO:
• 43.