Laboratory of Physicochemical Methods for Studying Biological Membranes

 Scientific Head: Sikorskaya Tatyana Vasilyevna, senior researcher, Cand. Sci. Biol., has managed the Laboratory since the establishment in 2024.

The laboratory includes 7 staff members.

The Laboratory of Physicochemical Methods for Studying Biological Membranes was established within the framework of the federal project entitled "Development of Human Capital for the Sake of Regions, Branches and Sector of Research and Developments” and the national Science and Universities project. The organization of the Laboratory was necessitated by the need to develop the study of biological membranes, a priority field of basic research in modern biology, in the Far East. The creation of the Laboratory will contribute to the personnel training and the development of the Synchrotron "Russian Photon Source" scientific research program in the field of experimental methods for studying biological membranes based on synchrotron radiation.

Range of organisms and objects under study: marine invertebrates, phyto- and zooplankton, bacteria and fungi.

Geography of research: the Far Eastern seas of Russia (the Bering Sea, Sea of Okhotsk, and Sea of Japan) and the South China Sea.

Main fields of research:

1. Structure and functions of biomembranes.
2. Biosynthesis of structural components of biomembranes.
3. Biological activity of structural components of biomembranes.

The heterogeneous lipid composition of the biomembrane, combined with proteins and glycans, modulates the collective properties of the membrane, shaping its fluidity, tendency to supramolecular phase, and normal functioning. Controlled distribution of lipids over various cell membranes plays a key role in cell's life and death. The arrangement of lipids in the biomembrane is known to be associated with the processes of apoptosis, carcinogenesis, and cell division. Studying the biomembrane structure, the native composition of lipids, their distribution in the membrane, and their relationship to membrane proteins is a promising direction in such fields as biochemistry, pharmacology, and ecology. Biomembrane research is an important area of lipidomics. The general aspects of lipidomics are applicable to both marine invertebrates and humans. These studies will create a basis for a common database of lipid markers involved in various physiological processes. Coral bleaching is one of the laboratory's research topics. Coral reefs are among the most important marine ecosystems. Due to their ecological significance and the threat of their extinction posed by global warming and anthropogenic pressure, they are actively studied by scientists worldwide. The scientific activity of the laboratory is aimed at studying the biochemical aspect of this issue. The effort to identify the relationship between physiological processes and dynamics of membrane lipid content during coral bleaching is expected to become a contribution to the development of methods for efficient environmental monitoring of the coral reef ecosystem, which will allow prediction of coral survival in various regions of the world’s oceans. Marine organisms are a source of biologically active compounds including ether-bond lipids or ether lipids. Studies on biosynthesis of lipids with a simple ether bond and their biological activity will help identify new functions of these lipids in pathological conditions.

Basic and applied results:

Corals contain hundreds of molecular species of lipids. It is lipidomic changes that reliably indicate physiological processes in a symbiotic coral organism and can be used to assess the impact of adverse environmental factors on coral reefs. When exposed to adverse environmental conditions, corals lose their symbionts (bleach). During bleaching, the profile of the molecular species of membrane lipids changes substantially. As part of the research on this topic, dynamics of membrane lipid content was studied during bleaching and subsequent recovery of the symbiotic corals Sclerophytum heterospiculatum (Verseveldt, 1970) and Acropora aspera (Dana, 1846) exposed to thermal stress. One of the major molecular species of phospholipids in the soft coral S. heterospiculatum is ether phosphatidylethanolamines (PE) with the polyunsaturated fatty acid (PUFA) 20:4n-6, while the reef-building coral А. cerealis has ether molecular species of PE with 20:4n-6 and 20:5n-3 PUFA. It has been shown that under stress, the coral can use these lipids as protection against oxidative stress. The researchers of our Youth Laboratory, after studying the transmembrane distribution of lipids in the plasma membrane of corals, have shown that the symmetry of the membrane relative to PE may vary depending on environmental conditions and the coral's diet. Furthermore, such lipids with a simple ether bond exhibit a wide range of biological activities. The members of the Youth Laboratory are also conducting research in this area.

Approaches and methods used:

One- and two-dimensional high-performance thin-layer chromatography (HPTLC); UV-Vis spectrophotometry; low-pressure column liquid chromatography; high-performance liquid chromatography (HPLC); preparative HPLC; capillary gas chromatography (GC); gas chromatography–mass spectrometry (GC–MS); tandem GC–MS/MS; tandem liquid chromatography–low- and high-resolution mass spectrometry with ion trap and time-of-fly analyzers (LCMS-IT-TOF); cytofluorometric methods for cell research; various methods in molecular biology.

Laboratory equipment and instruments:

• Equipment for lipidomic analysis: hybrid chromatograph–mass spectrometer with ion trap; Ohaus EX125 laboratory balance; rotary evaporator; etc.
• Equipment for molecular biology: abacterial box, laboratory centrifuge with cooling; electrophoresis chamber; amplifier; etc.