John, I believe my statement is accurate. The Compton & Jones paper you cite states in the abstract: "Interactions are chiefly with arginine rather than primary amino groups; the other basic (His, Lys) and aromatic residues (Try, Tyr, and Phe) give slight responses. The binding behavior is attributed to Van der Waals forces and hydrophobic interactions." Also, 23 years later, the following paper provides a detailed study of the mechanism of Coomassie Brilliant Blue G-250 binding to proteins and discusses the hydrophobic interactions I mentioned between aromatic residues and the dye.
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 dont have ne aromatic residue 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 -- -- Michael C. Thompson Graduate Student Biochemistry & Molecular Biology Division Department of Chemistry & Biochemistry University of California, Los Angeles mi...@chem.ucla.edu