L lysine monohydrochloride

Antibiotic/antimycotic solution (100×), acetonitrile (ACN), anhydrous dimethyl sulfoxide (DMSO), Dulbecco’s modified Eagle’s medium (DMEM), 1-ethyl-3-(3-dimethyl aminopropyl)carbodiimide (EDC), ethanol, L-lysine monohydrochloride (Lys), poly-L-lysine hydrobromide (HPL; average molecular weight of 50 kDa), N-hydroxysuccinimide (NHS), 2-(N-morpholino)ethanesulfonic acid monohydrate (MES monohydrate), phosphate-buffered saline (PBS), trifluoroacetic acid (TFA), and 2-(4-amidinophenyl)-6-indolecarbamidine dihydrochloride (DAPI) were purchased from Sigma-Aldrich (St. Louis, MO, USA). Fetal bovine serum (FBS) was obtained from Gibco (Waltham, MA, USA) and chlorin e6 (Ce6) was obtained from Leap Chem (Hong Kong). An EZ-cytox kit was obtained from DoGenBio (Seoul, Republic of Korea).

Mycobacterial cultures were grown in Middlebrook 7H9 broth medium or on Middlebrook agar 7H10 (Becton Dickinson) medium supplemented with albumin-dextrose-catalase (ADC; Difco Laboratories) and containing 0.05% Tween 80 and 20 μg/mL kanamycin. The L-lysine monohydrochloride (Sigma) was dissolved in distilled water and used at a concentration of 40 μg/mL. Mycobacterial suspensions for animal inoculation were prepared in PBS from frozen glycerol stocks previously titrated by plating serial dilutions.

Stearic acid and SPAN 80 were purchased from Merck (Merck KGaA, Darmstadt, Germany). Arachidic acid, Tween 60, Tween 80, poly(vinyl alcohol), L-lysine monohydrochloride, lithium carbonate, dansyl chloride, methylamine hydrochloride, triethylamine and sodium acetate were purchased from Sigma-Aldrich (St. Louis, MO, USA) and Miglyol 812 was purchased from Caelo (Caesar & Loretz GmbH, Hilden, Germany). Precirol ATO 5 and Compritol 888 ATO were kindly provided by Gattefossé (Saint Priest Cedex, France). L-Phenylalanine ethyl-ester hydrochloride was purchased from Fluka (Fluka Chemie GmbH, Buchs, Switzerland), acetic acid was obtained from VWR Chemicals (VWR International S.A.S., Fontenay-sous-Bois, France) and acetonitrile and methanol were obtained from Honeywell (Honeywell Riedel-de Häen AG, Seelze, Germany). Aqueous solutions were prepared with double-deionized water (Arium Pro, Sartorius AG, Göttingen, Germany).

Lab grade stearic acid was purchased from Merck (© Merck KGaA, Darmstadt, Germany) and excipient grade stearic and Tween^® 60 were obtained from Acofarma (^® Acofarma–Acofarma Distribución, S.A. BCN, Spain). Arachidic acid, lab grade Tween^® 60, l-lysine monohydrochloride, lithium carbonate, dansyl chloride, ethylenediaminetetraacetic (EDTA) acid disodium salt dihydrate, dimethyl sulfoxide (DMSO), 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), Triton^tm X-100, methylamine hydrochloride, triethylamine, sodium acetate, pepsin and pancreatin (from porcine pancreas) were purchased from Sigma-Aldrich (St. Luis, MO, USA), l-phenylalanine ethyl-ester hydrochloride from Fluka (Fluka Chemie GmbH, Buchs, Switzerland), acetic acid from VWR Chemicals (VWR International S.A.S., Fontenay-sous-Bois, France), acetonitrile and methanol from Honeywell (Honeywell Riedel-de Häen AG, Seelze, Germany). Dulbecco’s Modified Eagle’s Medium (DMEM), penicillin–streptomycin (10,000 U/mL) mix, fetal bovine serum (FBS) and amphotericin B (Fungizone) were purchased from Gibco^® (Invitrogen Corporation, UK). FaSSGF and FeSSIF were purchased from Biorelevant.com Ltd (London, UK). Aqueous solutions were prepared with double-deionized water (Arium Pro, Sartorius AG, Göttingen, Germany).

Histone proteins were purchased from the following commercial sources: unfractionated whole histone from calf thymus (Sigma-Aldrich; H9250) and histone H3 from calf thymus (Roche; 11034758001). Proteases qualified for use in mass spectrometry sample preparation are as follows: trypsin (Promega; V5111), chymotrypsin (Promega; V1061), and clostripain (Promega; V1881). Standards used in LC-MS/MS are as follows: L-lysine monohydrochloride (Sigma-Aldrich; L-5626), Nε-monomethyl-L-lysine hydrochloride (Sigma-Aldrich; 04,685), Nε,Nε -dimethyl-L-lysine monohydrochloride (Sigma-Aldrich; 19,773), Nε,Nε,Nε-trimethyl-lysine hydrochloride (Sigma-Aldrich; T1660), L-arginine hydrochloride (Arg, Sigma-Aldrich; A-5131), NG-monomethyl-L-arginine monoacetate salt (Sigma-Aldrich; 475,886), NG,NG-dimethylarginine dihydrochloride (Sigma-Aldrich; D4268), NG,N′G-dimethyl-L-arginine dihydrochloride (Santa Cruz; sc-222070), L-histidine hydrochloride monohydrate (His, Wako; 084–00702), 3-methyl-L-histidine (Sigma-Aldrich; M9005), 1-methyl-L-histidine (Sigma-Aldrich; 67,520), Nω-propyl-L-arginine hydrochloride (Wako; 512–27111).

To reduce renal uptake of test items, aqueous L-lysine monohydrochloride (Sigma-Aldrich) solution (pH 7.3) mixed with gelofusine (Gelaspan, B. Braun Melsungen, Germany) was administered [20 (link), 21 ] as intravenous (iv) bolus at 4 mL/kg 30 min before radiotracer injection. Mass doses were 0.1 g/kg gelofusine and 1 g/kg L-lysine.

Dulbecco’s phosphate buffered saline, Tween^® 60, L-lysine monohydrochloride, lithium carbonate, dansyl chloride, metacrilamide, methylamine hydrochloride, triethylamine, and sodium acetate were purchased from Sigma-Aldrich (St. Louis, MO, USA), L-phenylalanine ethyl-ester hydrochloride from Fluka (Fluka Chemie GmbH, Buchs, Switzerland), acetic acid from VWR Chemicals (VWR International S.A.S., Fontenay-sous-Bois, France), and acetonitrile and methanol from Honeywell (Honeywell Riedel-de Häen AG, Seelze, Germany). Aqueous solutions were prepared with double-deionized water (Arium Pro, Sartorius AG, Göttingen, Germany) and all reagents were of analytical grade or higher.