A novel Zinc Porphyrin as an Antimicrobial


A novel Zinc Porphyrin as an Antimicrobial




One of the greatest threats to human health, and life, is the rise of antibiotic resistant bacterial infections. National summary data from the CDC estimates that at least 2,049,442 million illnesses and 23,000 deaths occur each year as the result of antibiotic resistant bacteria and fungi. Pseudomonas aeruginosa is an opportunistic bacterium that causes infection ad forms biofilm that are difficult to treat due to antibiotic resistance. We are the co-inventors of two patented novel technologies for the treatment of antibiotic resistant bacteria. Both treatments make use of a novel porphyrin ZnPor (US Patent # 9,364,537) that does not require using traditional photo-activation i.e., it exhibits unique dark toxicity. Current studies have indicated the utility of photodynamic therapy using porphyrins in the treatment of bacterial infections. Photoactivation of porphyrins results in the production of singlet oxygen that damages biomolecules associated with cells and biofilms, e.g., proteins, polysaccharides, and DNA. The effect of a ZnPor on P. aeruginosa PAO1 biofilms and planktonic cells was assessed without photoactivation. Biofilms were visualized using confocal laser scanning microscopy (CLSM) and cell viability determined using the LIVE/DEAD BacLight viability assay and standard plate count was used for planktonic cell viability. At a concentration of 25µM ZnPor, there was substantial killing of P. aeruginosa PAO1 wild-type biofilms with significant disruption of the biofilm matrix or structure. Biofilms pretreated with ZnPor without photoactivation were substantially more sensitive to tobramycin than untreated biofilms. 4-log10 reduction in viable cells of wild-type PAO1 planktonic cells was observed at a concentration of 12.5 µM. Our results suggest that ZnPor permeates into the PAO1 cells and makes the cell membrane permeable/compromised. Also, the interaction study of ZnPor with the PAO1 DNA shows that the porphyrin interacts strongly with the DNA and aggregates around the helix of the DNA.

Publication Date


Project Designation

Graduate Research

Primary Advisor

Jayne B Robinson

Primary Advisor's Department



Stander Symposium poster


Presenter: Nehaben Nik Patel

A novel Zinc Porphyrin as an Antimicrobial