Ruiz-González, Rubén Cortajarena, Aitziber L. Mejias, Sara H. Agut, Montserrat Nonell, Santi Flors, Cristina Singlet Oxygen Generation by the Genetically Encoded Tag miniSOG The genetically encodable fluorescent tag miniSOG is expected to revolutionize correlative light- and electron microscopy due to its ability to produce singlet oxygen upon light irradiation. The quantum yield of this process was reported as Φ<sub>Δ</sub> = 0.47 ± 0.05, as derived from miniSOG’s ability to photooxidize the fluorescent probe anthracene dipropionic acid (ADPA). In this report, a significantly smaller value of Φ<sub>Δ</sub> = 0.03 ± 0.01 is obtained by two methods: direct measurement of its phosphorescence at 1275 nm and chemical trapping using uric acid as an alternative probe. We present insight into the photochemistry of miniSOG and ascertain the reasons for the discrepancy in Φ<sub>Δ</sub> values. We find that miniSOG oxidizes ADPA by both singlet oxygen-dependent and -independent processes. We also find that cumulative irradiation of miniSOG increases its Φ<sub>Δ</sub> value ∼10-fold due to a photoinduced transformation of the protein. This may be the reason why miniSOG outperforms other fluorescent proteins reported to date as singlet oxygen generators. alternative probe;light irradiation;miniSOG increases;singlet oxygen generators;electron microscopy;photoinduced transformation;probe anthracene dipropionic acid;Singlet Oxygen Generation;Genetically Encoded Tag miniSOGThe;correlative light;miniSOG oxidizes ADPA;tag miniSOG;ΦΔ values;singlet oxygen;1275 nm;uric acid 2016-02-19
    https://acs.figshare.com/articles/journal_contribution/Singlet_Oxygen_Generation_by_the_Genetically_Encoded_Tag_miniSOG/2399683
10.1021/ja4020524.s001