Scope of Research

The Laboratory for Oral Infectious Diseases studies bacterial viruses (or bacteriophages) and their products in order to develop antimicrobial agents that are useful in the treatment of antibiotic-resistant bacterial infections.

Among the several ongoing research efforts in this lab are studies focused on the Enterococcus faecalis bacteriophage φEf11, which involve the 

  • creation of genetic variants useful in the treatment of E. faecalis infections.
  • cloning, expression and isolation of the lytic enzymes of this virus.
  • evaluation of isolated lytic enzymes for usefulness in the treatment of antibiotic-resistant enterococcal infections.

Research is also focused on the development of bacteriophage lytic enzymes effective in the treatment of antibiotic-resistant E. faecium infections and gram-negative infections. 

In addition, future studies will investigate the mechanism of prophage activation by human fibroblastic cells in lysogenic strains of the periodontal pathogen Aggregatibacter actinomycetmcomitans (Aa).

Collaborations

The laboratory’s notable research partnerships include the following.

  • A collaboration with the University of Rome to genetically engineer a variant of the E. faecalis bacteriophage EF1TV to have greater lytic activity than the wild type.
  • A collaboration with the State University of Rio de Janeiro to learn the mechanism by which Aa lysogens are induced by human fibroblasts.
  • An ongoing collaboration with the J. Craig Venter Institute for sequencing and analyzing the genomes of bacteriophages studied at the lab.

Facilities

Located on the third floor of the Kornberg School of Dentistry, the Laboratory of Oral Infectious Diseases is a micro- and molecular-biology facility encompassing 1,500 square feet. The laboratory contains the following research and equipment spaces.

  • Dark room
  • Equipment room
  • Glassware processing and sterilization facility
  • Sterile room for aseptic transfers
  • Tissue culture laboratory
  • Walk-in cold room
  • Walk-in warm room

Several pieces of major equipment are housed in these research spaces, including the following.

  • Beckman L7-65 ultracentrifuge
  • CO2 incubator
  • Explosion-resistant refrigerator
  • Inverted phase contrast microscope
  • Laminar flow hood
  • Lyophilizer
  • Microcentrifuge
  • Spectrophotometer
  • Speed evaporator
  • Superspeed centrifuges with associated rotors
  • Tangential flow ultrafiltration apparatus
  • Vacuum oven

The laboratory was designated as a biosafety BSL-2 facility by Temple University’s Biosafety Committee.

A researcher in a white lab coat examines a petri dish.

Faculty

Recent Funding

“Development of a genetically engineered E. coli bacteriophage for treatment of enteric infections”
Principal Investigator, Janssen Research & Development

March 1, 2016–Feb. 28, 2017
Amount: $462,699

“Enterococcus faecalis biofilm disruption by a genetically-engineered bacteriophage”
Principal Investigator, Janssen Research & Development

Feb. 1, 2017–Dec. 31, 2017
Amount: $226,495

“Development of a bacteriophage lysin active against E. coli”
Principal Investigator, BioStrategy Partners

June 1, 2017–Dec. 31, 2017
Amount: $58,237

“Amendment to Development of a bacteriophage lysin active against E. coli”
Principal Investigator, BioStrategy Partners
September 2019–April 2020
Amount: $14,310

Selected Publications

Tinoco, J.M., Liss, N., Zhang, H., Nissan, R., Gordon, W., Sassone, L., Stevens, R. Antibacterial effect of genetically-engineered bacteriophage φEf11/φFL1C(Δ36)PnisA on dentin infection with antibiotic-resistant Enterococcus faecalis. Archives of Oral Biology, 82: 166-170, 2017. 
PMID 28646693

Zhang, H., Buttaro, B.A., Fouts, D.E., Sanjari, S., Evans, B.S., Stevens, R.H. Bacteriophage φEf11 ORF28 endolysin: A multi-functional lytic enzyme with properties distinct from all other identified Enterococcus faecalis phage endolysins. Applied and Environmental Microbiology 85(13): e00555-19
PMID 30979842
PMCID PMC6581165

Stevens, R., Zhang, H., Sedgley, C., Bergman, A., Reddy Manda, A. The prevalence and impact of lysogeny among oral isolates of Enterococcus faecalis. Journal of Oral Microbiology, 11:1.
1643207, DOI: 10.1080/20002297.2019.1643207.
PMID 31489125
PMCID PMC6711143