发信人: sunnyday (飞鸟), 信区: Biology
标 题: Re: Help! Qualify Question
发信站: The unknown SPACE (Tue Nov 5 13:34:47 2002) WWW-POST

FPLC or HPLC Gel filtration column, viscosity assay or sedimentation velocity
assay can be used for dimer/polymer assay. Native gel is also used for such
purpose. SDS-PAGE is NOT!
Antibody? Buy it from commercial company.
Actually, for your question, you DON"T have to do those dimer things at all.
They are the properties of a protein but has NOTHING to do with purity.
A proper folding is needed, if your lab is gonna to test it's activity.
However,if only the protein sequence is corncerned (e.g., for antigen) then
it's fine to leave it alone.
Crystallography and CD spectra deal with different perspectives of a protein.
Crystallograpgy go for the structure information while CD only tell you
whether the protein is in the right folding stage( i.e., whether the protein
was denatured)

【 在 bigfatliar (smurf) 的大作中提到: 】
: 记得好象是用gel filtration 和 SDS-PAGE 来定dimer还是monomer. Native PAGE 来
定
: 纯度。怎样才能够选到合适的 antibody 呢？
:
: 另外，sunnyday, 有必要看正确的folding吗？我并不知道正确的folding是怎样的。CD
: Spectra 可以代替 Crystallography 吗？
:
: 【 在 sunnyday (飞鸟) 的大作中提到: 】
: : Simply this way:
: : 1. SDS-PAGE: show the appoximate MW of the protein and the purity of your
: : sample.
: : 2. WB: show that you got the right protein
: : 3. CD spectra: show that your protein is in the right folding stage.
: :
: : Done.
: :
: : You don't need to do Mess Spec or Seq to demonstrate the purity.
: : No dimer/polymer information is needed according your question's context.
: : Also, about the basis for those creteria, I think you should be able to
: handle
: : it.
: : 【 在 bigfatliar (smurf) 的大作中提到: 】
: : : here's a question from last year's Ph. D. Qualify Exam in my department,
: can
: : : anyone give any suggestions on how to answer it? Many thanks!
: : :
: : : Discuss the biochemical evidence that you would utilize to convince your
: : : advisor that you had finally purified a protein that was critical for
your
: : : studies. Clearing state your creteria for protein purity and the basis
for
: : : using these creteria.
: : :
: : :
: : :
: :
: :
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※ 修改:·sunnyday 於 Nov 5 13:34:47 修改本文·[FROM: 159.178.]
※ 来源:．The unknown SPACE bbs.mit.edu．[FROM: 159.178.]