|
|
| View previous topic :: View next topic |
| Author |
Message |
Tim Tyler
Guest
|
|
| Back to top |
|
 |
| |
Ads |
Advertising
Sponsor
|
|
Perry E. Metzger
Guest
|
 Posted: Sun Feb 03, 2008 12:57 am Post subject: Re: [Sci.nanotech] Extra base pairs |
 |
|
Tim Tyler <seemysig@cyberspace.org> writes:
That was already done some years ago. It was very cool work, but it
isn't actually of that much immediate use because we can't even design
proteins very deliberately with the existing set of amino
acids. Certainly if we *could* do high quality protein design, this
would open up new capabilities, but we've yet to even scratch the
possibilities the existing amino acids give us.
| Quote: |
Start by adding the common non-coded amino acids, with corresponding
mRNAs - that way at least the new organisms will stand a chance in
the wild without being dependent on dietary supplements.
|
Actually, unless they have synthetic pathways for the new amino acids,
they would still need to have them supplied. (Of course, that is
unlikely to matter in practice unless the new amino acids are used in
proteins in critical metabolic pathways).
Perry |
|
| Back to top |
|
|
| |
Ads |
Advertising
Sponsor
|
|
Tim Tyler
Guest
|
| Posted: Sun Feb 03, 2008 8:06 am Post subject: Re: [Sci.nanotech] Extra base pairs |
|
|
Perry E. Metzger wrote:
Really? The current paper is here:
Discovery, Characterization, and Optimization of an Unnatural Base Pair
for Expansion of the Genetic Alphabet
http://pubs.acs.org/cgi-bin/abstract.cgi/jacsat/asap/abs/ja078223d.html
It is the only one in PubMed that mentions dSICS and dMMO2.
| Quote: |
It was very cool work, but it isn't actually of that much immediate
use because we can't even design proteins very deliberately with
the existing set of amino acids.
|
There's still trial and error approaches - such as GAs.
With extra aminos, there would be many new mutations of
*existing* enzymes, some of which might well be better
than the originals. It would not be difficult to explore
the immediate vicinity of existing solutions for new enzyme
finds - once the appropriate mRNAs were in place.
| Quote: |
Start by adding the common non-coded amino acids, with corresponding
mRNAs - that way at least the new organisms will stand a chance in
the wild without being dependent on dietary supplements.
Actually, unless they have synthetic pathways for the new amino acids,
they would still need to have them supplied. [...]
|
Thus either dietary supplements, or the use of common non-coded amino
acids - which can be obtained from sources such as animal flesh.
Synthetic routes in bacteria would be needed in the long term -
otherwise the dietary supplements would wind up costing too much.
--
__________
|im |yler http://timtyler.org/ tim@tt1lock.org Remove lock to reply. |
|
| Back to top |
|
|
| |
Ads |
Advertising
Sponsor
|
|
Bob
Guest
|
| Posted: Sun Feb 10, 2008 11:16 pm Post subject: Re: [Sci.nanotech] Extra base pairs |
|
|
On Sat, 02 Feb 2008 18:57:51 -0000, "Perry E. Metzger"
<perry@piermont.com> wrote:
Yes. Apparently what is new here is some specifics, and the quality of
this particular pair.
This pair does not use hydrogen-bonding to provide pairing, but rather
only a hydrophobic matching. One advantage they note of this is that
the new bases are less likely to cause problems by mispairing with the
natural bases. The error rates with natural bases are a serious
problem, that nature deals with in very complex ways. Fitting more
bases into that same system -- with good accuracy -- may be very
challenging.
At the end, they say:
"Our characterization of the d5SICS:dMMO2 heteropair
demonstrates that its synthesis and extension are both relatively
efficient and selective. The pair compares favorably with all
previously characterized unnatural base pair candidates for
which relevant kinetic data are available."
They also suggest that their approach can be used to develop better
pairs. (They do note that one of their new bases tends to pair with
self.)
Looks like a small step in an ongoing process.
| Quote: |
It was very cool work,
|
:-)
Indeed, Kool, who has done much of the work on novel base pairs, has
praised it.
bob |
|
| Back to top |
|
|
| |
Ads |
Advertising
Sponsor
|
|
|
|
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
|
|
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
