|Foster Frey, Juli|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 5/21/2014
Publication Date: N/A
Citation: Interpretive Summary:
Technical Abstract: Multi-drug resistant bacteria are a persistent problem in modern health care, food safety and animal health. There is a need for new antimicrobials to replace over-used conventional antibiotics. Staphylococcus aureus (S. aureus) is a notorious pathogen for both animal and human health with multi-drug resistant strains highly prevalent. This pathogen has also evolved another way to evade antibiotic treatment by invading and residing intracellularly within animal cells. New treatments that reduce resistance development and tackle intracellular pathogens are sorely needed. We have identified three enzyme activities that cut the cell wall structural element (peptidoglycan) of S. aureus in three unique regions. Any one of the three enzymatic activities can kill the cells when exposed externally. When fused these three enzyme domains maintain each of their activities in the final triple-acting fusion. We have shown that these triple-acting enzyme constructs greatly reduce resistance development compared to the parental enzymes alone and are effective at reducing S. aureus nasal colonization by 97%. We also show that when these enzymes (single, double or triple domain harboring) are fused to protein transduction domains, they can enter animal cells and reduce the intracellular load of the pathogen up to 97% in three different cell types from three different species. The effect is maintained in two different animal models (osteomyelitis and mastitis of mice) as well as staphylococcal biofilms. The findings of this work identify the necessary components and methodology for generating multiple domain fusions with elements to address intracellular and multi-drug resistant pathogens. These findings will aid scientists in the development of these and similar molecules as commercializable antimicrobials for use in animal production, animal and human health and food safety.