发信人: crystalmaker (风雨无阻), 信区: Biology
标 题: Re: 请教一个蛋白质晶体结构的问题
发信站: Unknown Space - 未名空间 (Sat May 8 18:34:59 2004) WWW-POST

In my experinces ( I have grown more than 15 crystals of more than 10
proteins), 1-5 mg can give a good chance. Usually people first try
screening kits (there are several kinds of kits), and if you are lucky
enough, you can get good crystals at the first trial. In this case,
you only need 1-2 mg protein.
If you can not find condition by screening, or you need to optimize
the conditions that give bad crstals, it will difficulty to say, but 5-10
mg can give very good chance.

But some proteins, really difficult to crystallize, and some never give
crystals. (then NMR can be a choice). I have 3 proteins, never get the
crystals, or never get good crystals (can be used in X-ray to collect
data). For example, people spent more than 30 years to grow monomeric
insulin (native, not shorten form).



【 在 visa (有卡人士) 的大作中提到: 】
: our collaborator normally ask for 10~20mg of protein (13kD), if protein
: is bigger, they ask for more. THis is for mature crystallization protocol
: if they need to try to get crystal, they will ask for more
: 【 在 melsant (melsant) 的大作中提到: 】
: : 现在的x-ray crystography 技术能够在最少多少克蛋白质的基础上测结构？
: : 换句话说， 长单晶的蛋白质最少用量可以是多少？x-ray对蛋白质单晶有
: : 破环作用对吧？那么测出一个结构来需要最少几克的蛋白质呢？
: : 外行好奇的问。
:
:

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