Proteose peptone

Two different culture media were used: (1) Supplemented Brain Heart Infusion (BHI) medium: BHI medium (VWR, Avantor, PA, USA), 2% (w/v) gelatin (Sigma-Aldrich, Hamburg, Germany), 1% (w/v) yeast extract (VWR, Avantor, PA, USA), and 0.1% (w/v) soluble starch (Merck, Gernsheim, Germany); (2) New York City III (NYCIII) medium: 0.4% (w/v) HEPES buffer (Merck, Gernsheim, Germany), 1.5% (w/v) proteose peptone (VWR, Avantor, PA, USA), 0.5% (w/v) sodium chloride (VWR, Avantor, PA, USA), 0.5% (w/v) glucose (VWR, Avantor, PA, USA), 2.5% (w/v) yeast extract (VWR, Avantor, PA, USA), and 10% (v/v) fetal bovine serum (FBS) (Sigma-Aldrich, Hamburg, Germany). The incubation conditions used were as follows: 24 h, 10% CO₂, and 37 °C (Binder GmbH, Tuttlingen, Germany).

Chemicals and media components were purchased from manufacturers as follows: tryptone (Becton Dickinson, United States); proteose peptone (Difco, United States); K₂HPO₄, MgSO₄, NaOH, H₃PO₄ (POCH, Poland); LB, MOPS, L-leucine (Leu), and L-valine (Val) (Bioshop, Canada); glycerol (VWR International, United States).
King’s B medium (KB) composition was as follow: 10 g/L glycerol, 20 g/L proteose peptone, 1.5 g/L K₂HPO₄, 1.5 g/L MgSO₄ × 7H₂O, and 100 mM MOPS (King et al., 1954 (link); Biniarz et al., 2018 ). Cultures in bioreactors were performed in KB-mod medium with Leu or Val (Biniarz et al., 2018 ): 80 g/L glycerol, 15 g/L tryptone, 5 g/L Leu/Val, 1.5 g/L K₂HPO₄, 1.5 g/L MgSO₄ × 7H₂O, 100 mM MOPS. The pH of all media used was set at 7.0 with 6 M NaOH or 6 M HCl prior to autoclaving.

E. coli ATCC
9637, L. lactis ATCC 11454,
and B. cereus ATCC 11778 were purchased
from the American Type Culture Collection (ATCC). E.
coli BL21 (DE3) and E. coli XL1 were obtained from the lab of Prof. Christian Becker at the
University of Vienna and used without further cultivation. Microscope
slides were obtained from VWR.
d-Glucose monohydrate,
(3-aminopropyl)triethoxysilane (APTES), di-potassium hydrogen phosphate,
potassium dihydrogen phosphate, dimethyl sulfoxide (DMSO), divinylbenzene
(DVB), and styrene were supplied by Merck. Proteose peptone was obtained
from VWR chemicals. Yeast extract, 2,2′-azobis(2-methylpropionitrile)
(AIBN), and toluene were purchased from Sigma Aldrich. NaCl was supplied
by AppliChem. [3-(Methacryloyloxy)propyl]trimethoxysilane was obtained
from Alfa Aesar. All chemicals were used as received without further
purification.