G'day Petr;
Thanks for the references - you are a wealth of information. I have been
thinking similar things myself, but have never formalised it to the nice
extent you have, so I've found this exchange very educational, but I may
have to go and re-do the paper I'd just written.
> Len, to be the devil's advocate, how many molecules of HIV protease do
> you think migt be in the budding HIV virion? Just wondering if our
> concept of pH and ionic strength is at all applicable to similar
> biological objects. I think that enzyme kinetics in /membranes/,
> /virions/, and organized (sequestered) structures like that would be
> much better described using a completely different concepts, as well as
> different mathematical formalism (e.g., Markov chains of statistics,
> instead of the Mass-Action Law, the way neurologists think about the
> kinetics of ion channels).
I am not sure I follow you here. If you are saying that cellular pH and
ionic strength are possibly different in a virion, I'd have to agree whole
heartedly, but defining the system is very hard as there's no reason to
assume it's static. In fact it very well could be dynamic. I have thought
of how many molecules of HIV-1 PR are in a virion and have calculated how
much HIV-1 protease is in a person's peripheral blood stream, but I can't
find where I've written it down at the moment. It was based on:
Richieri et al., (1998) Characterization of highly purified, inactivated
HIV-1 particles isolated by anion exchange chromatography. Vaccine 1998
16: 119-29.
It's a Remune paper, but don't hate them because they're
immunologists. They qualitate 85% of the total proteins and quantitatively
assign values for some 50% of the proteins. If you consider how much virus
is in a mL of blood and how much blood is in an average person you can
derive rough mg values for the amount of protease. It is interesting to
compare this to how much inhibitors are administered therapeutically.
> Nope. Plus I don't have a lab anymore (unless you want to invite me for
> a visit, to see if I can still hold a pipettor), just writing computer
> programs these days.
Petr, if you ever wanted a sunny holiday in Queensland, you'd be more than
welcome to some lab time (but you'd have to guest lecture of course). Hell
you could even play salesman and try and flog your wares ;-). I'm sure I'd
benefit a lot from a visit.
> > I want to get my hands on the common drugs to try in my assay for direct
> > comparison, do you happen to have any Saquinavir/ritonavir/Indinavir or
> > VX-478 lying around?
>> I don't, but I can ask some doctor friends of mine, or maybe someone
> else reading this can supply you with the goodies.
If anyone could provide them, I'd be very appreciative. I've tried
contacting the companies directly but have had no responses in over 12
months.
Len...
