Estimation of tyrosine-40-DNA distance in the filamentous phage Pf1 by analysis of its intrinsic fluorescence properties.
Iodination of the exposed Tyr-25 in the coat protein decreases the fluorescence intensity of the filamentous phage Pf1 to less than 3% of its original fluorescence. If one assumes that the total residual fluorescence originates from the non-iodinated, buried Tyr-40, one can estimate the distance between Tyr-40 and the DNA bases in Pf1 to be less than 7 A, making use of the Foerster law for fluorescence energy transfer. The result is consistent with the idea that Tyr-40-DNA interaction is responsible for the unusually large axial base separation in Pf1-DNA.
D001435:Bacteriophages / Q000648:ultrastructure*; D004279:DNA, Viral / Q000032:analysis*; D008856:Microscopy, Fluorescence; D014443:Tyrosine; D014759:Viral Envelope Proteins / Q000032:analysis*
D004279:DNA, Viral; D014759:Viral Envelope Proteins; D014443:Tyrosine