physicochemical characterization of proteins - (Mar/20/2006 )

Please see the attachment.
I don't understand what information can the UV absorption spectrophotometry tell.

plz give me suggestion.

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that's a standard curve. you can use it to determine your protein concentration by its absorbance at 280nm.

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Thanks for your reply.
can the curve tell anything about the structure of the protein?
I don't understand why the curve reaches plateau finally.

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it's not really a plateau. it is linear only until a certain point (usually from 0.1 to 0.7 A). some of the limitation is caused by the spectrophotometers detector limits.

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for the linear part, can I say that there may be a Trp residue on the protein surface?

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at 280nm you are reading ring structures in your aa sequence (ie trp, phe, tyr). the more rings the greater the absorbance.

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