Alexej M. Bogdanov

Ph.D. (biological sciences)


Research fellow (Laboratory of Biophotonics)

Phone: +7 (499) 742-81-22

E-mail: noobissat@gmail.com

Selected publications

  1. Мамонтова А.В., Григорьев А.П., Царькова А.С., Лукьянов К.А., Богданов А.М. (2017). БОРЬБА ЗА ФОТОСТАБИЛЬНОСТЬ: МЕХАНИЗМЫ ОБЕСЦВЕЧИВАНИЯ ФЛУОРЕСЦЕНТНЫХ БЕЛКОВ. Биоорг. хим. 43 (6), 598–607 [+]

    Modern biological science needs to visualize the objects under investigation at the cell, organelle and individual molecule levels. A significant place in the spectrum of imaging methods is occupied by fluorescent methods based on the excitation of fluorophores, which the objects of investigation are labeled with, followed by subsequent registration of the photons emitted by them. Fluorescent proteins (FP) are very popular as genetically encoded fluorescent labels for lifetime imaging of target structures and processes in living systems. One of the key characteristics of FPs is their photostability, i.e. resistance to photochemical reactions, leading to the disappearance of the fluorescent signal. This review describes the currently known molecular mechanisms underlying photobleaching, and the methods used to improve the photostability of fluorescent proteins.

    ID:1916
  2. Bogdanov A.M., Acharya A., Titelmayer A.V., Mamontova A.V., Bravaya K.B., Kolomeisky A.B., Lukyanov K.A., Krylov A.I. (2016). Turning On and Off Photoinduced Electron Transfer in Fluorescent Proteins by π-Stacking, Halide Binding, and Tyr145 Mutations. J. Am. Chem. Soc. 138 (14), 4807–17 [+]

    Photoinduced electron transfer in fluorescent proteins from the GFP family can be regarded either as an asset facilitating new applications or as a nuisance leading to the loss of optical output. Photooxidation commonly results in green-to-red photoconversion called oxidative redding. We discovered that yellow FPs do not undergo redding; however, the redding is restored upon halide binding. Calculations of the energetics of one-electron oxidation and possible electron transfer (ET) pathways suggested that excited-state ET proceeds through a hopping mechanism via Tyr145. In YFPs, the π-stacking of the chromophore with Tyr203 reduces its electron-donating ability, which can be restored by halide binding. Point mutations confirmed that Tyr145 is a key residue controlling ET. Substitution of Tyr145 by less-efficient electron acceptors resulted in highly photostable mutants. This strategy (i.e., calculation and disruption of ET pathways by mutations) may represent a new approach toward enhancing photostability of FPs.

    ID:1526
  3. Mamontova A.V., Bogdanov A.M., Lukyanov K.A. (2015). Influence of cell growth conditions and medium composition on EGFP photostability in live cells. BioTechniques 58 (5), 258–261 [+]

    Photostability is a key characteristic of fluorescent proteins. It was recently demonstrated that green fluorescent protein (GFP) photobleaching in live cells can be suppressed by changes in medium composition. Here we show that Ham's F12 medium provides very high enhanced GFP (EGFP) photostability during fluorescence microscopy of live cells. This property of Ham's F12 medium is associated with decreased concentrations of riboflavin and pyridoxine, and increased concentrations of FeSO4, cyanocobalamine, lipoic acid, hypoxanthine, and thymidine compared with DMEM. We also found that the rate of EGFP photobleaching strongly depends on cell growth conditions such as cell density and the concentration of serum. We conclude that both imaging medium composition and the physiological state of the cells can strongly affect the photostability of fluorescent proteins. Thus, accurate comparison of the photostabilities of fluorescent proteins should be performed only in side-by-side analysis in identical cell growth conditions and media.

    ID:1300
  4. Pletneva N.V., Pletnev S.V., Bogdanov A.M., Goriacheva E.A., Artemev I.V., Suslova E.A., Arkhipova S.F., Pletnev V.Z. (2014). Three dimensional structure of the dimeric gene-engineered variant of green fluorescent protein EGFP-K162Q in P6(1) crystal space group. Bioorg. Khim. 40 (4), 414–20 [+]
    ID:1326
  5. Bogdanov A.M., Mishin A.S., Yampolsky I.V., Belousov V.V., Chudakov D.M., Subach F.V., Verkhusha V.V., Lukyanov S., Lukyanov K.A. (2009). Green fluorescent proteins are light-induced electron donors. Nat. Chem. Biol.  (5), 459–461 [+]

    Proteins of the green fluorescent protein (GFP) family are well known owing to their unique biochemistry and extensive use as in vivo markers. We discovered that GFPs of diverse origins can act as light-induced electron donors in photochemical reactions with various electron acceptors, including biologically relevant ones. Moreover, via green-to-red GFP photoconversion, this process can be observed in living cells without additional treatment.

    ID:22