期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1978
卷号：75
期号：2
页码：833-837
DOI：10.1073/pnas.75.2.833
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：A blue fluorescence protein has been isolated and purified from extracts of the luminous bacterium Photobacterium phosphoreum. It is a single polypeptide of molecular weight 22,000 with absorption maxima at 274 and 418 nm. It is efficiently fluorescent ({phi}F 0.45), with a fully corrected spectral maximum (476 nm) and distribution identical to the in vivo bioluminescence from this same type of bacterium. At low concentration this fluorescence shifts towards the red and becomes identical to the in vitro bioluminescence emission. This spectral shift apparently results from a change in the protein pulled by dissociation of the chromophore (Kd [unk] 10-7 M). If the blue fluorescence protein is included in the in vitro bioluminescence reaction with reduced FMN, oxygen, aldehyde, and luciferase (P. phosphoreum), the bioluminescence spectrum is shifted towards the blue from its maximum at 490 nm to one at 476 nm, where it is again identical in all respects to the in vivo bioluminescence spectrum. This is accompanied by an increase in the initial light intensity by an order of magnitude at saturating levels of blue fluorescence protein, and the specific light yield of the luciferase is increased 4-fold. It is suggested that the blue fluorescence protein acts as a sensitizer of the bacterial bioluminescence reaction.
