Antimicrobial Activity of 2-(Piperazin-1-yl)naphtho[2,3-d]thiazole-4,9-dione against Staphylococcus Strains
Tamami Haraguchi,
Saki Hayashi,
Seira Nakasaka,
Yoshiro Hatanaka,
Toshihiro Nagao,
Shigemitsu Tanaka,
Miki Yoshii,
Fumiko Hara,
Masayori Hagimori,
Miyako Yoshida
Affiliations
Tamami Haraguchi
Department of Clinical Pharmaceutics, Faculty of Pharmaceutical Sciences, Mukogawa Women’s University, 11-68 Koshien 9-Bancho, Nishinomiya 663-8179, Hyogo, Japan
Saki Hayashi
Department of Clinical Pharmaceutics, Faculty of Pharmaceutical Sciences, Mukogawa Women’s University, 11-68 Koshien 9-Bancho, Nishinomiya 663-8179, Hyogo, Japan
Seira Nakasaka
Department of Clinical Pharmaceutics, Faculty of Pharmaceutical Sciences, Mukogawa Women’s University, 11-68 Koshien 9-Bancho, Nishinomiya 663-8179, Hyogo, Japan
Yoshiro Hatanaka
Osaka Research Institute of Industrial Science and Technology, 1-6-50 Morinomiya, Joto-ku, Osaka 536-8553, Osaka, Japan
Toshihiro Nagao
Osaka Research Institute of Industrial Science and Technology, 1-6-50 Morinomiya, Joto-ku, Osaka 536-8553, Osaka, Japan
Shigemitsu Tanaka
Osaka Research Institute of Industrial Science and Technology, 1-6-50 Morinomiya, Joto-ku, Osaka 536-8553, Osaka, Japan
Miki Yoshii
Osaka Research Institute of Industrial Science and Technology, 1-6-50 Morinomiya, Joto-ku, Osaka 536-8553, Osaka, Japan
Fumiko Hara
Department of Analitical Chemistry, Faculty of Pharmaceutical Sciences, Mukogawa Women’s University, 11-68 Koshien 9-Bancho, Nishinomiya 663-8179, Hyogo, Japan
Masayori Hagimori
Department of Analitical Chemistry, Faculty of Pharmaceutical Sciences, Mukogawa Women’s University, 11-68 Koshien 9-Bancho, Nishinomiya 663-8179, Hyogo, Japan
Miyako Yoshida
Department of Clinical Pharmaceutics, Faculty of Pharmaceutical Sciences, Mukogawa Women’s University, 11-68 Koshien 9-Bancho, Nishinomiya 663-8179, Hyogo, Japan
There is an urgent need to discover and develop novel antibacterial agents. Accordingly, we synthesised 2-(piperazin-1-yl)naphtho[2,3-d]thiazole-4,9-dione (PNT), which exhibits antimicrobial activity. The aim of this study was to characterise PNT as an effective antimicrobial agent. Fluorescence microscopy was used to measure PNT’s uptake into microbial cells (strains of Staphylococcus epidermidis, Staphylococcus aureus, and methicillin-resistant S. aureus (MRSA)), transmission electron microscopy (TEM) was used to investigate the influence of PNT on the configuration of microbial cells, and a DNA gyrase supercoiling assay was used to investigate whether PNT inhibits DNA gyrase. PNT was taken up by more than 50% of microbial cells within 30 min. Using TEM, hollowed-out bacterial cytoplasms were observed in the specimen treated with PNT, although there was no disintegration of the bacterial membrane. In the DNA gyrase supercoiling assay, a dose-dependent reduction in fluorescence intensity was observed as the concentration of PNT increased. This suggests that PNT is taken up by microbial cells, resulting in cell disruption, and it reveals that one of the mechanisms underlying the antimicrobial activity of PNT is the inhibition of DNA gyrase.
