Metronidazole

All animal experiments were performed in accordance with relevant guidelines and regulations. The study protocol was approved by Institutional Animal Care and Use Committee (IACUC) of the University at Buffalo and all methods were carried out in compliance with the ARRIVE guidelines. Wild-type BALB/cJ mice (Jackson Laboratory; Cat#000651) were given 1 mg/ml of Kanamycin sulfate (IBI Scientific; Cat# 25389–94-0) via autoclaved drinking water for 5 days to suppress host microbiota. After 2 days of washout period, approximately 1 × 10⁹ CFU of P. gingivalis was administered via oral gavage using stainless steel feeding tube (see below for P. gingivalis cultivation method). Interleukin 10 (Il10)-deficient BALB/cJ mice (Jackson Laboratory; Cat#004333) were given antibiotic cocktail of 1 mg/ml each of ampicillin (Teknova; Cat#50–841-073), neomycin sulfate (Fagron; Cat#804599), metronidazole (Spectrum Chemical; Cat#M1284), and 0.5 mg/ml of Vancomycin hydrochloride (Fagron; Cat#804147) via drinking water for 4 weeks (refilled every 96 h) to ablate host microbiota (See below for cecal microbiota transplantation method). All animals were single housed and raised in sealed positive pressure cages (Allentown).

Mice were treated with antimicrobials in drinking water. Antibiotics used were ampicillin (0.5 mg/ml) (Sigma Aldrich; St. Louis, MO), gentamicin sulfate (0.5 mg/ml) (Corning; Manassas, VA), metronidazole (0.5 mg/ml) (Spectrum Chemical, Gardena, CA), neomycin sulfate (0.5 mg/ml) (EMD Millipore; Billerica, MA), and vancomycin (0.25 mg/ml) (VWR Life Science). All of the antimicrobials were dissolved in non-acidified autoclaved reverse osmosis drinking water. Antimicrobial water was changed every week.

CamSA, 7-deoxy-CamSA, and 12-deoxy-CamSA were synthesized by the Abel-Santos laboratory^{30 (link)}. Sodium cholate, chenodeoxycholate (CDCA), taurocholate, metanilic acid (mSA), cholestyramine, cefoperazone, HistoDenz, PMA, and HPLC-grade solvents were obtained from Sigma-Aldrich Corporation (St. Louis, MO, USA). Artificial gastric juice was obtained from Ricca Chemical Company (Arlington, TX, USA). The Vivid™ CYP3A4 Green Screening Kit (Cat #P2857) was obtained from Thermo Fisher Scientific (Waltham, MA, USA). Clindamycin phosphate and ketoconazole was obtained from TCI (Portland, OR, USA). Metronidazole was obtained from Spectrum Chemical (Gardena, CA, USA). Microbiological media, colistin, vancomycin, gentamicin, sodium thioglycolate, ammonium acetate, HCl, sodium bicarbonate, and kanamycin were obtained from VWR (Radnor, PA, USA). C. difficile strain 630 was obtained from the American Type Culture Collection (ATCC).