Kitchell B B, Merrill S P, Henkens R W
Biochim Biophys Acta. 1977 Apr 4;475(3):536-47. doi: 10.1016/0005-2787(77)90068-5.
Fluorescence properties of the icosahedral RNA virus bacteriophage f2 and its empty capsid are reported. Emission is dominated by tryptophan with a maximum wavelength of 320 nm for f2 and its empty capsid. In addition to this short wavelength maximum, perturbation and denaturation studies indicate the inaccessibility of the tryptophan residues. However a high degree of thermal quenching and a red shift in fluorescence emission on heating suggest a noncooperative structural transition, not a denaturation, which allows buried tryptophans to become exposed to solvent. Therefore the tryptophan residues may be located between subunits. Fluorescence from tyrosine is detected near 315 nm for both f2 and its empty capsid, and may indicate an unusual tyrosine environment. Sensitization of tryptophan fluorescence by tyrosine absorption and low values of polarization indicate tyrosine leads to tryptophan and tryptophan leads to tryptophan energy transfer. The presence of RNA in f2 decreases the efficiency of these transfer processes, but does not significantly affect the other reported fluorescence properties.
报道了二十面体RNA病毒噬菌体f2及其空衣壳的荧光特性。f2及其空衣壳的发射以色氨酸为主，最大波长为320nm。除了这个短波长最大值外，扰动和变性研究表明色氨酸残基难以接近。然而，高度的热猝灭和加热时荧光发射的红移表明这是一种非协同结构转变，而非变性，这使得埋藏的色氨酸能够暴露于溶剂中。因此，色氨酸残基可能位于亚基之间。在f2及其空衣壳中均在315nm附近检测到酪氨酸的荧光，这可能表明酪氨酸环境异常。酪氨酸吸收引起的色氨酸荧光敏化以及低偏振值表明酪氨酸向色氨酸以及色氨酸向色氨酸存在能量转移。f2中RNA的存在降低了这些转移过程的效率，但对其他报道的荧光特性没有显著影响。
