Re: [ccp4bb] co-crystallization

- Protein crystallography

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- Protein purification
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CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999

Previous message:
Subject: Re: Program to fill unitcell randomly
From: "Edward A {- dot -} Berry" BerryE {- at -} UPSTATE {- dot -} EDU
Date: 2008-12-01

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Subject: Re: O/T: can a protein which dimerizes in solution crystallize as a monomer?
From: "Fischmann, Thierry" thierry {- dot -} fischmann {- at -} SPCORP {- dot -} COM
Date: 2008-12-01

Subject: Re: co-crystallization
From: Phoebe Rice price {- at -} UCHICAGO {- dot -} EDU
Date: 2008-12-01

Just to be a pedantic pain - Km is not necessarily Kd. I
think that assumption only holds if the chemical step
following substrate binding is rate-limiting.
Phoebe

---- Original message ----
>Date: Mon, 1 Dec 2008 15:34:59 +0100
>From: mesters
>Subject: Re: [ccp4bb] co-crystallization
>To: CCP4BB@JISCMAIL.AC.UK
>
>Yes!, there is:
>
>the fraction of occupied protein with substance can be
calculated: S /
>(S + Km) with S being the concentration of the compound.
>
>So, if S = Km, half of the sites are occupied (it follows from
>Michaelis-Menten theory).
>
>In order to saturate the enzyme for 90,90909 % with the compound:
>
>1) S = 10 x Kd (concentration of S at least 10 times the Kd)
>and
>2) S > P (total concentration of S must be larger than total
>concentration of protein or "binding sites")
>
>Depending on the solubility of the compound, this is not always
>possible. In such a case, you need to use DMSO and/or add
solid compound
>to the protein solution and leave it for quite some time for the
>compound to finally bind to the protein.
>
>- J. -
>
>
>yangliuqing wrote:
>> Hello,everyone,
>> I have a question for cocrystallization, is there some
relationship
>> between Km value and substrate concentration when making
>> cocrystallization? How can I know the substrate is enough
for binding?
>> Thank you very much!
>> liuqing
>>
>>
------------------------------------------------------------------------
>> å…«å¦å¨±ä¹åŒ…æ‰“å¬ï¼ŒMSNèµ„è®¯é€Ÿé€’å¸®ä½ å¿™ï¼ äº†è§£è¯¦ç»†ï¼
>>
>
>
>--
>Dr. Jeroen R. Mesters
>Gruppenleiter Strukturelle Neurobiologie und Kristallogenese
>Institut fÃ¼r Biochemie, UniversitÃ¤t zu LÃ¼beck
>Zentrum fÃ¼r Medizinische Struktur- und Zellbiologie
>Ratzeburger Allee 160, D-23538 LÃ¼beck
>Tel: +49-451-5004065, Fax: +49-451-5004068
>Http://www.biochem.uni-luebeck.de
>Http://www.iobcr.org
>Http://www.selfish-brain.org
>Http://www.opticryst.org
>--
>If you can look into the seeds of time and say
>which grain will grow and which will not - speak then to me
(Macbeth)
>--
Phoebe A. Rice
Assoc. Prof., Dept. of Biochemistry & Molecular Biology
The University of Chicago
phone 773 834 1723
http://bmb.bsd.uchicago.edu/Faculty_and_Research/01_Faculty/01_Faculty_Alphabetically.php?faculty_id=123

RNA is really nifty
DNA is over fifty
We have put them
both in one book
Please do take a
really good look
http://www.rsc.org/shop/books/2008/9780854042722.asp

CCP4bb navigation

CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999

Previous message:
Subject: Re: Program to fill unitcell randomly
From: "Edward A {- dot -} Berry" BerryE {- at -} UPSTATE {- dot -} EDU
Date: 2008-12-01