PFI:AIR - TT: Using A. niger as a host to express recombinant endolysin

University Of Maryland Baltimore County, Baltimore MD

Investigators

Abstract

This PFI:AIR Technology Translation project focuses on an important agricultural and human-health related problem. For over 50 years, it is has been common practice in the agricultural industry to add low doses of traditional (i.e., "medically important") antibiotics to animal feed to improve production efficiency of food animals. While these "antibiotic growth promoters" provide tremendous economic benefit, this practice also leads to antibiotic-resistant bacterial strains which have the potential to infect humans. As a result, the US Food and Drug Administration has implemented measures to stop this practice. While numerous alternatives to medically important antibiotics have been proposed, most have not been commercially successful as they are not adequately effective. As an alternative to medically important antibiotics, the use of antimicrobial proteins has great promise, but a significant limitation to their commercial production has been cost. Thus the ability to economically manufacture antimicrobial proteins would represent a significant benefit to the agricultural industry as it would allow farmers to maintain high levels of productivity while not generating antibiotic-resistant strains that pose a danger to humans. This proposal explores the potential of replacing medically-important antibiotic feed-additives with antimicrobial protein (AMP). Work described here seeks to generate proof-of-concept data, expressing model AMPs, at commercially viable titers, using recombinant filamentous fungi. This project employs a commercially-relevant fungal species (Aspergillus niger), to express model endolysin proteins with demonstrated bactericidal activity. To increase both expression and extracellular secretion of two different endolysin enzymes several approaches will be used, exploring the impact of genomic location, transcriptional promoter, and secretion signal sequence. Employing several approaches will increase the likelihood for success and will also allow identification of the most relevant factors leading to a high-producing recombinant fungal strain. This understanding will allow efficient generation of additional production strains for different proteins or peptides. In addition, personnel involved in this project, both a postdoctoral scientist and several undergraduate students, will be trained in a cross-disciplinary environment that will increase their research capacity. Personnel will also participate in entrepreneurial education experiences, through conducting customer discovery activities related to this project. This will primarily involve contacting potential stakeholders, along the entire value chain, to test hypotheses related to future commercialization.