Effect of Photodynamic Antibacterial Chemotherapy Combined with Antibiotics on Gram-Positive and Gram-Negative Bacteria.
Yana Ilizirov, Andrei Formanovsky, Irina Mikhura, Yossi Paitan, Faina Nakonechny, Marina Nisnevitch
Author Information
Yana Ilizirov: Department of Chemical Engineering, Biotechnology and Materials, Ariel University, Ariel 4070000, Israel. yanailizirov1@gmail.com.
Andrei Formanovsky: Shemyakin���Ovchinnikov Institute of Bioorganic Chemistry Russian Academy of Sciences, 117977 Moscow, Russia. formanovsky@yandex.ru.
Irina Mikhura: Shemyakin���Ovchinnikov Institute of Bioorganic Chemistry Russian Academy of Sciences, 117977 Moscow, Russia. ivmikhura@yandex.ru.
Yossi Paitan: Clinical Microbiology Laboratory, Meir Medical Center, Kfar Saba 4428164, Israel. yossi.paitan@clalit.org.il.
Faina Nakonechny: Department of Chemical Engineering, Biotechnology and Materials, Ariel University, Ariel 4070000, Israel. fainan@ariel.ac.il.
Marina Nisnevitch: Department of Chemical Engineering, Biotechnology and Materials, Ariel University, Ariel 4070000, Israel. marinan@ariel.ac.il. ORCID
The well-known and rapidly growing phenomenon of bacterial resistance to antibiotics is caused by uncontrolled, excessive and inappropriate use of antibiotics. One of alternatives to antibiotics is Photodynamic Antibacterial Chemotherapy (PACT). In the present study, the effect of PACT using a photosensitizer Rose Bengal alone and in combination with antibiotics including methicillin and derivatives of sulfanilamide synthesized by us was tested against antibiotic-sensitive and antibiotic-resistant clinical isolates of Gram-positive and Gram-negative . Antibiotic-sensitive and resistant strains of were eradicated by Rose Bengal under illumination and by sulfanilamide but were not inhibited by new sulfanilamide derivatives. No increase in sensitivity of cells to sulfanilamide was observed upon a combination of Rose Bengal and sulfanilamide under illumination. All tested strains (MSSA and MRSA) were effectively inhibited by PACT. When treated with sub-MIC concentrations of Rose Bengal under illumination, the minimum inhibitory concentrations (MIC) of methicillin decreased significantly for MSSA and MRSA strains. In some cases, antibiotic sensitivity of resistant strains can be restored by combining antibiotics with PACT.
