A Macroporous Magnesium Oxide-Templated Carbon Adsorbs Shiga Toxins and Type III Secretory Proteins in Enterohemorrhagic Escherichia coli, Which Attenuates Virulence

Hidetada Hirakawa; Kazutomo Suzue; Motoyuki Uchida; Ayako Takita; Wataru Kamitani; Haruyoshi Tomita

doi:10.3389/fmicb.2022.883689

A Macroporous Magnesium Oxide-Templated Carbon Adsorbs Shiga Toxins and Type III Secretory Proteins in Enterohemorrhagic Escherichia coli, Which Attenuates Virulence

Front Microbiol. 2022 May 6:13:883689. doi: 10.3389/fmicb.2022.883689. eCollection 2022.

Authors

Hidetada Hirakawa¹, Kazutomo Suzue², Motoyuki Uchida³, Ayako Takita¹, Wataru Kamitani², Haruyoshi Tomita^{1

4}

Affiliations

¹ Department of Bacteriology, Graduate School of Medicine, Gunma University, Maebashi, Japan.
² Department of Infectious Diseases and Host Defense, Graduate School of Medicine, Gunma University, Maebashi, Japan.
³ R&D Strategy & Planning Department, Kureha Corporation, Iwaki, Japan.
⁴ Laboratory of Bacterial Drug Resistance, Graduate School of Medicine, Gunma University, Maebashi, Japan.

Abstract

Enterohemorrhagic Escherichia coli (EHEC) is one of the most common foodborne pathogens. However, no drug that prevents the severe complications caused by this bacterium has been approved yet. This study showed that a macroporous magnesium oxide (MgO)-templated carbon material (MgOC₁₅₀) adsorbs Shiga toxins, and Type III secretory EspA/EspB proteins responsible for EHEC pathogenesis, and decreases the extracellular levels of these proteins. On the other hand, this material did not affect the growth of EHEC. Citrobacter rodentium traditionally used to estimate Type III secretion system-associated virulence in mice is highly virulent. The survival period of infected mice was prolonged when MgOC₁₅₀ was administered. This adsorbent disturbed neither mammalian cells nor normal intestinal bacteria, such as Enterococcus hirae, Lactobacillus acidophilus, and Lactobacillus casei. In contrast, MgOC₁₅₀ adsorbed antimicrobial agents, including β-lactams, quinolones, tetracyclines, and trimethoprim/sulfamethoxazole. However, fosfomycin and amikacin were not adsorbed. Thus, MgOC₁₅₀ can be used with fosfomycin and amikacin to treat infections. MgOC₁₅₀ is used for industrial purposes, such as an electrode catalyst, a bioelectrode, and enzyme immobilization. The study proposed another potential application of MgOC₁₅₀, assisting anti-EHEC chemotherapy.

Keywords: Shiga toxin; Type III secretion system; antimicrobial chemotherapy; antimicrobial resistance; bacterial pathogenesis; enterohemorrhagic Escherichia coli; porous carbon; virulence.