What was hydroxy-lysine?

[David I Resnick]

In article <2ojups$o2l at mercury.hgmp.mrc.ac.uk> mlush at crc.ac.uk (Mr. M.J. Lush) writes:

>	   We have managed to produce a limited amount of protein 
>   sequence by edman degredation,  unfortunatly one of these contains 
>   two hydroxy-lysines.  

>	   We wish to use these protein sequences to devise degenerate 
>   oligos so we want to know:-

>	   What was hydroxy-lysine (OH-lys) before it was altered? 

It was lysine.  LysOH is occasionally glycosylated in collagen, but I
guess it wasn't in your case I guess as that would have probably made
it unidentifiable on your HPLC.

>	   Is this an artifact?

I dunno.  I wouldn't thing so.  

>	   Has OH-lys been found in proteins _other_ than collagen?
>  And if so what was it doing there?

Hydroxylysine has also been seen in the proteins containing short (<30
gly-x-y repeats) coll. domains.  E.g. secreted proteins like C1q, mannose binding
protein, conglutinin and transmembrane proteins like the macrophage
scavenger receptor.  If your Edman degradations are not putting the
hydroxylysine in the Y positions of the Gly-X-Y repeat it could be
interesting, since I've not heard of it being elsewhere.


-David
--
       David Resnick                           dresnick at athena.mit.edu