At 01:19 AM 1/29/97 GMT, Donny Wong wrote:
>Hi everyone,
>>Does anyone know of a method of labeling proteins (radioactively or
>without radiation) that doesnt involve iodination? I'm worried about the
>dangers of working with iodine (a gamma emitter) and I can't metabolically
>label with 35-S Methionine because i'm giong to be working with proteins
>that have already been purified.
I have used protein methylation as a way of labelling proteins. It is simple
and gentle and allows for the incorporation of 3-H and/or 14-C via lysine
groups.
The method requires formaldehyde and reducing agent (eg pyridine borane), see
Longstaff and Rando Biochemistry 24, 8138-8145, (1985). It should be OK if your
protein does not have sensitive lysine residues and you are not worried about
radioactive formaldehyde. I would be interested in any experiences you had if
you went ahead and used this method as I intend to do some more work with
methylated
proteins again soon.
Colin Longstaff
