remeans at husc9.harvard.edu (Robert Means) writes:
>Subject: Help with Prot.-DNA interactions
>Newsgroups: bionet.molbio.proteins
>Summary:
>Keywords:
>Hello,
> I have a problem that I'm hoping that some of you can help me
>with, thus saving me a great deal of legwork in an unfamiliar subject.
>While looking at something completely different, we engineered a purine
>to pyrimidine change into a stretch of DNA that is involved with
>interactions with a certain protein. (sorry to be so circumspect)
>At any point, we weren't sure what section of this protein was
>interacting with the DNA and to make a long story short, we are getting a
>compensatory mutation in the protein which causes a Val to Ile change.
>While this change is fairly conservative, I was wondering if anybody out
>there could make any suggestions about what this change might mean.
>Amoung DNA-protein interactions, are there any noted preferences for a
>Val over Ile when interacting with a purine, or vise-versa? Even if no
>one out there can give me a dirrect answer could somebody give a
>suggestion as to how I could screen a large number of DNA-interacting
>proteins for possible clues as to what is going on.
> Thanks in advance,
> Bob Means
>New England Regional Primate Research Center...Where the primates have
>better living conditions than the grad. students.
>"Why don't activists ever picket for better living conditions for
>me?"--any impoverished grad student
A simple interpretation would involve steric factors.
In going from purine to pyrimidine, you have decreased
the size of the nucleotide (assuming this is a ssDNA
binding protein). In going from val to ile, you are
making a compensatory increase to fill a potential void.
--
Mark Griep
Department of Chemistry ____ ____ __________________
Center for Biotechnology | | / | | \_
University of Nebraska | |/ | | \
