13c l methionine

Cells were grown in Luria Bertani broth (LB) to OD₆₀₀ ≈ 0.8 at 37°C, and expression was induced by addition of 1 mM isopropyl-β-D-thiogalactoside (IPTG). Cells expressing HSPB1, DNAJA2, and DNAJB1 chaperone variants were allowed to proceed overnight at 25°C and cells expressing tau constructs at 18°C.
Isotopically labeled tau and tau^4R proteins for NMR were grown in M9 H₂O media supplemented with ¹⁵NH₄Cl (and ¹³C-glucose) as the sole nitrogen (and carbon) source. Protein expression was induced with 1 mM IPTG at 18°C overnight.
Labeled DNAJB1^154-341, Ydj1^111-351, and Ydj1^256-409 were grown at 37°C in M9 D₂O media supplemented with [²H,¹²C]-glucose and ¹⁵NH₄Cl as the sole source of carbon and nitrogen. In the case of DNAJB1, 2-ketobutyric acid-¹³C₄,3,3-d₂ sodium salt (60 mg/L), 2-ketoisovaleric acid-¹³C₄,d₃ sodium salt (80 mg/L), and ¹³C-L-methionine (100 mg/L) (Cambridge Isotope Laboratories) were added 1 hr prior to induction with 1 mM IPTG, following the procedure of Tugarinov et al., 2006 (link) to produce U-²H, ¹⁵N, ¹³CH₃-ILVM labeled protein. Proteins were expressed at 25°C overnight.