Hplc grade acetonitrile

All the chemicals and reagents used in this study were of analytical grade. GPI0363 was obtained from the chemical library of the Drug Discovery Initiative at the University of Tokyo and its purity was confirmed by ultra-performance liquid chromatography-high resolution mass spectrometry (m/z: 343.1968 [M + H]⁺; calculated for C₁₉H₂₄N₄O: 343.1934) (ESI Fig. 7†). Rifampicin (potency: 1029 μg mg⁻¹), ammonium acetate, and HPLC grade acetonitrile were obtained from Fujifilm Wako Pure Chemical Industries, Ltd., Osaka, Japan. Fidaxomicin (purity: ≥95%) was obtained from Cayman Chemical (Ann Arbor, MI, USA). Salmon sperm DNA, actinomycin D (purity: ∼98%), and phenol : chloroform : isoamyl alcohol (125 : 24 : 1, v/v/v) were obtained from Sigma Aldrich, Tokyo, Japan. Tryptone, tryptic soy broth (TSB), yeast extract, and Mueller-Hinton broth (MHB) were obtained from Becton, Dickinson and Company (Franklin Lakes, NJ, USA). RNase inhibitor was obtained from Applied Biosystems (Beverly, MA, USA). ATP, CTP, GTP, UTP, and yeast tRNA were obtained from Ambion (Austin, TX, USA). [α-³²P] UTP was obtained from PerkinElmer, Waltham, MA, USA. The E. coli RNAP holoenzyme and core enzyme were obtained from New England Biolabs (Ipswich, MA, USA), and TALON® magnetic beads were obtained from Takara Bio USA Inc. (Mountain View, CA, USA).

VRCZ and VNO were purchased from Toronto Research Chemicals Inc. (North York, ON, Canada). They were dissolved in DMSO as 150 mM stock solutions and were used immediately or stored at −20 °C until used. HPLC-grade acetonitrile and methanol were purchased from Wako Pure Chemicals (Osaka, Japan). Photoproduct of VNO (P-VNO) was generated from VNO by irradiating with UVB irradiation (500 mJ/cm²). Afloqualone (AQ) was obtained from Tanabe Seiyaku Co., Osaka, Japan. The solution of PBS contained 0.3 mM AQ was prepared as described previously^{20 (link)}. Sparfloxacin, the AhR antagonists CH223191 and GNF351 were procured from Sigma-Aldrich, St. Louis, MO. KCZ, TBF and ITCZ were purchased from Wako Pure Chemicals, Osaka, Japan. Recombinant human TNF-α was purchased from R&D Systems, Minneapolis, MN.

ITZ, OH-ITZ, KT-ITZ, ND-ITZ, and ITZ-d9 as an internal standard (IS) were obtained from Toronto Research Chemicals Inc. (Toronto, Ontario, Canada). HPLC-grade acetonitrile and methanol were purchased from Wako Pure Chemicals (Osaka, Japan). Stock solutions of ITZ (50 μg/mL), OH-ITZ (50 μg/mL), KT-ITZ (50 μg/mL), ND-ITZ (2 μg/mL), and ITZ-d9 (50 μg/mL) were prepared with methanol. Stock solutions of ITZ, OH-ITZ, KT-ITZ, and ND-ITZ were diluted in acetonitrile to yield their standard solutions.

Tama Biochemical Co., Ltd. (Tokyo, Japan) provided fish oil DHA-46, and NPO Arcoiris Naturaleza (Matsudo, Chiba, Japan) provided GNO. From Oriental Yeast Co., Ltd. (Tokyo, Japan), corn oil was purchased. Ammonium acetate, LC/MS grade 2-propanol and methanol, HPLC grade acetonitrile, chloroform, formic acid, acetic acid, and ultrapure water were purchased from Wako Pure Chemical Industries (Osaka, Japan). From Sigma-Aldrich (St. Louis, MO, USA), sodium formate was purchased.

A LC-VP series (Shimadzu, Kyoto, Japan) consisting of an SIL-HTc autosampler, LC-10ADvp Pump, CTO-10ACvp column oven, and DGU-14AM degasser was used to set the reverse-phase liquid chromatographic conditions. The column was a Cadenza CD-C18 column (100 × 2 mm i.d., 3 μm, Imtakt Corp., Kyoto, Japan) used at 45°C. The mobile phase included water/acetonitrile/formic acid 95/5/0.05 (v/v/v, Solvent A) and water/acetonitrile/formic acid 35/65/0.05 (v/v/v, Solvent B). The gradient elution programs were 0% B (0-1 min with an isocratic gradient), 0–40% B (1-2 min with a linear gradient), 40% B (2–7 min with an isocratic gradient), 40–100% B (7–12 min with a linear gradient), 100% B (12–14 min with an isocratic gradient), 100–0% B (14-15 min with a linear gradient), and 0% B (15-16 min with an isocratic gradient) at a flow rate of 0.3 mL/min. The autosampler tray was cooled to 45°C and the injection volume was 5 μL. HPLC grade acetonitrile and formic acid were purchased from WAKO.