Re: [ccp4bb] how to quantitate protein which dont have ne aromatic residue

2011-04-11 Thread Roger Rowlett
In general, most protein quantification methods have significant problems with idiosyncracy, because proteins are quite variable in composition and structure. The best method is to use is the absorption at 280 nm, but this is quantitatively useful only if the

Re: [ccp4bb] how to quantitate protein which dont have ne aromatic residue

2011-04-10 Thread E rajakumar
Strcutural Biology Program Memorial Sloan-Kettering Cancer Center New York-10021 NY 001 212 639 7986 (Lab) 001 917 674 6266 (Mobile) --- On Sat, 9/4/11, Arpit Mishra ar...@igib.in wrote: From: Arpit Mishra ar...@igib.in Subject: [ccp4bb] how to quantitate protein which dont have ne aromatic

Re: [ccp4bb] how to quantitate protein which dont have ne aromatic residue

2011-04-10 Thread gauri misra
Hi, You can read the spectrophotometric absorption at 280 nm and 200nm in UV range. It should serve your purpose and provide a decent idea for the amount of protein in the sample. Provided that absorbance at 280nm is given by aromatic rings but at the same time absorbance at 200nm is contributed

[ccp4bb] how to quantitate protein which dont have ne aromatic residue

2011-04-09 Thread Arpit Mishra
hello everybody i am working on the protien which dont have any aromatic residue i do fplc other purification using 220 absorption, but i want to quantitate protein precisely i have tried using BCA nd bradford but both methods quantification is not matching,,so any one is having sum idea how to

Re: [ccp4bb] how to quantitate protein which dont have ne aromatic residue

2011-04-09 Thread VAN RAAIJ , MARK JOHAN
you can do amino acid analysis on your pure protein, using a commercial or academic service - I hope these are still around. You should only need to do this once, then relate the result to your A220, BCA and Bradford assays. Mark Quoting Arpit Mishra: hello everybody i am working on the

Re: [ccp4bb] how to quantitate protein which dont have ne aromatic residue

2011-04-09 Thread Michael Thompson
: [ccp4bb] how to quantitate protein which dont have ne aromatic residue hello everybody i am working on the protien which dont have any aromatic residue i do fplc other purification using 220 absorption, but i want to quantitate protein precisely i have tried using BCA nd bradford but both

Re: [ccp4bb] how to quantitate protein which dont have ne aromatic residue

2011-04-09 Thread Philippe Dumas
:00 US/Canada Pacific Subject: [ccp4bb] how to quantitate protein which dont have ne aromatic residue hello everybody i am working on the protien which dont have any aromatic residue i do fplc other purification using 220 absorption, but i want to quantitate protein precisely i have

Re: [ccp4bb] how to quantitate protein which dont have ne aromatic residue

2011-04-09 Thread John A. Newitt
At 9:47 AM -0700 4/9/11, Michael Thompson wrote: Bradford dye binds to hydrophobic residues, mainly aromatics, The statement above is not accurate. Compton and Jones. Anal. Biochem. 151(2): 369-374, 1985 - John --

Re: [ccp4bb] how to quantitate protein which dont have ne aromatic residue

2011-04-09 Thread Dima Klenchin
It is not surprising that your bradford and BCA assays don't agree if you have no aromatic amino acids in your protein. Bradford dye binds to hydrophobic residues, mainly aromatics, so I would guess your bradford is consistantly giving lower measurements than the BCA assay. I also wouldn't be

Re: [ccp4bb] how to quantitate protein which dont have ne aromatic residue

2011-04-09 Thread Michael Thompson
. Georgiou, et al. Anal Bioanal Chem. 2008 May;391(1):391-403. Cheers, Mike - Original Message - From: John A. Newitt newit...@gmail.com To: CCP4BB@JISCMAIL.AC.UK Sent: Saturday, April 9, 2011 12:06:23 PM GMT -08:00 US/Canada Pacific Subject: Re: [ccp4bb] how to quantitate protein which