Lysine Methylation

• 1mg/ml protein
• 50mM HEPES (pH7.5)
• 250mM NaCl
• Do NOT use Tris

Add per 1ml protein:

• 20μl 1M dimethylamine-borane complex (ABC) – freshly prepared
• 40μl 1M formaldehyde (from 37% stock)

Mix gently and incubate for 2hrs at 4°C

Add again:

• 20μl 1M dimethylamine-borane complex
• 40μl 1M formaldehyde

Continue incubation for 2hrs at 4°C

Then add

• 10μl 1M dimethylamine-borane complex (ABC)

Incubate O/N at 4°C

Remove precipitated protein (up to 50%) by centrifugation

Concentrate and put protein on Gel Filtration column in a Tris containing buffer, eg:

• 20mM Tris (pH7.5)
• 200mM NaCl
• 1mM DTT