Peptidoglycan hydrolase antimicrobials for eradicating lactobacilli that contaminate and reduce ethanol yields in biofuel fermentation

A method of controlling lactic acid bacterial contamination in ethanol fermentation comprising:

• introducing a fermentation mixture comprising yeast S. cerevisiae into a vessel used during ethanol production;
• introducing a recombinant yeast host cell comprising genes encoding a recombinant bacteriophage lytic endolysin as an active agent to the vessel used during ethanol production, and fermenting the fermentation mixture by said yeast to produce ethanol;
• wherein the recombinant endolysin is an antimicrobial agent having exolytic activity for at least one targeted Gram positive lactic acid bacterial species in an amount effective to at least reduce the levels of growth of and colonization by at least one targeted lactic acid bacterial species present in the vessel during ethanol production without inhibiting the growth of said fermenting yeast or recombinant yeast host cells in the vessel thereby resulting in increased ethanol production from the fermentation mixture.

A method of controlling lactic acid bacterial contamination in ethanol fermentation comprising:

• introducing a fermentation mixture comprising yeast S. cerevisiae into a vessel used during ethanol production;
• introducing a recombinant yeast extract from a host cell comprising genes encoding a recombinant bacteriophage lytic endolysin as an active agent to the vessel used during ethanol production, and fermenting the fermentation mixture by said yeast to produce ethanol;
• wherein the recombinant endolysin is an antimicrobial agent having exolytic activity for at least one targeted Gram positive lactic acid bacterial species in an amount effective to at least reduce the levels of growth of and colonization by at least one targeted lactic acid bacterial species present in the vessel during ethanol production without inhibiting the growth of said fermenting yeast or recombinant yeast host cells in the vessel thereby resulting in increased ethanol production from the fermentation mixture.