Stephen M Hughes

US Patent:

20140273137, Sep 18, 2014

Filed:

Mar 15, 2013

Appl. No.:

13/837654

Inventors:

The Unites Stated of America, as represented by the Secretary of Agriculture - , US
Dwayne R. Roach - Laurel MD, US
Piyum A. Khatibi - Dunlap IL, US
Kenneth M. Bischoff - Morton IL, US
Stephen R. Hughes - Peoria IL, US

Assignee:

The United States of America, as represented by the Secretary of Agriculture - Washington DC

International Classification:

C12P 7/10
C12P 7/06

US Classification:

435165, 435161, 435163

Abstract:

Ethanol losses due to bacterial contamination in fermentation cultures weakens the economics of biofuel production. species are the predominant contaminant. Bacteriophage lytic enzymes are peptidoglycan hydrolases which degrade Gram positive cell walls when exposed externally and are a novel source of antimicrobials. The streptococcal phage λSA2 endolysin construct demonstrated strong lytic activity towards 17 of 22 strains of lactobacilli, staphylococci or streptococci maintaining optimal specific activity under fermentation conditions toward substrates. bacteriophage endolysin constructs LysA, LysA2 and LysgaY showed exolytic activity towards 60% of the lactobacilli tested including four isolates from fuel ethanol fermentations. Presence of ethanol (≦5%) did not affect lytic activity. Lysins were able to reduce both and contaminants in mock fermentations of corn fiber hydrolysates. Recombinant LysA and λSa2 expressed in the yeast are functional; LysA was shown to reduce lactobacilli in experimentally infected fermentations.