Physical methods for studying flavoprotein photoreceptors

Molecular mechanisms of dark-to-light state transitions in flavoprotein photoreceptors have been the subject of intense investigation. Blue-light sensing flavoproteins fall into three general classes that share aspects of their activation processes: LOV domains, BLUF proteins, and cryptochromes. In all cases, light-induced changes in flavin redox, protonation, and bonding states result in hydrogen-bond and conformational rearrangements important for regulation of downstream targets. Physical characterization of these flavoprotein states can provide valuable insights into biological function, but clear conclusions are often challenging to draw owing to complexities of data collection and interpretation. In this chapter, we briefly review the three classes of flavoprotein photoreceptors and provide methods for their recombinant production, reconstitution with flavin cofactor, and characterization. We then relate best practices and special considerations for the application of several types of spectroscopies, redox potential measurements, and X-ray scattering experiments to photosensitive flavoproteins. The methods presented are generally accessible to most laboratories.

The Institute of Protein Research of the Russian Academy of Sciences Is 50 Years Old

Here I introduce collection of review articles written by members of the Institute of Protein Research of the Russian Academy of Sciences. This collection commemorates the 50th anniversary of the Institute. The review articles cover a broad range of problems concerning the spatial structure of protein molecules, including the state of the molten globule, protein-RNA interactions, polysome and ribosome structure, the molecular colony method, and the original methods for studying the structure of proteins. Several of the reviews consider the practical use of knowledge about the structure of proteins and protein polymers. They reflect both the long experience of the authors and contemporary scientific data.