Biosynthesis of ribose-5-phosphate (R5P) underlies all biosynthetic processes associated with biomass growth. Actively dividing cells continuously require building blocks for genome replication, synthesis of ribosomes and other derivatives containing R5P as a carbohydrate backbone. The main source of R5P in the cell is the pentose phosphate pathway (PPP), which is an anabolic sensor designed to coordinate the level of pentose phosphates and reduced NADPH required for anabolic processes. This review is devoted to a comparative analysis of R5P biosynthesis pathways among different domains of microorganisms, the features of PPP regulation in bacterial cells depending on physiological conditions, as well as genetic modifications of PPP and their effect on cell viability. We emphasize that ribose metabolism is a factor in the consolidation of cellular homeostasis under conditions of intensive biomass growth and the discrepancy between the processes of ribose synthesis and consumption is marked by spontaneous cell death.

The Kola Superdeep Well (SG-3) is an outstanding achievement of Soviet science and technology, drilled in Precambrian crystalline rocks and reached a depth of 12262 m. It was one of a series of super deep wells planned within the framework of the program “Earth's Interior Exploration and Superdeep Drilling”. In order to achieve record depths, unique domestic drilling equipment and materials capable of working at high temperatures and pressures were created. A fundamentally new technology for drilling wells using hydraulic downhole motors was developed. Despite difficult drilling conditions and repeated acci-dents, SG-3 has fulfilled almost all the tasks assigned to it. The well was penetrated with full core sampling, which was subjected to comprehensive study. This made it possible to study the deep structure of the Earth's crust and to revise the interpretation of depth seismic data. It was found that changes in the physical properties of rocks at great depths had been erroneously interpreted as a change in their composition. It made it possible to assess the prospects of deep horizons of the Pechenga structure for copper-nickel mineralisation by uncovering a previously unknown body of ore-bearing hyperbasites. New information was obtained on the temperature gradient, which turned out to be significantly higher than expected, as well as on the vertical metamorphic zoning along the borehole section. The composition and physical properties of rocks in deep horizons were investigated. Tectonic fault zones and six types of ore mineralisation were identified in the borehole section. New data on ore formation processes at great depths have been obtained, which is an important contribution to the theory of mineral deposit formation

Palladium mineralization was registered in the Kola superdeep borehole (SG-3) for the first time in samples from deep horizons (in the fault zone at ~10 km). A proper palladium mineral (merenskyite) with the formula Pd_1.00(Te_1.21Bi_0.79)_2.00 was detected using the analytical electron microscopy and EBSD methods. The unusually high content of bismuth in the discovered merenskyite crystal most likely indicates the lower temperatures of its formation from a bismuth-rich fluid. This is supported by numerous finds of associated bismuth minerals (native and intermetallic minerals, sulfides, tellurides, and sulfotellurides) as well. A close geochemical association of noble and rare elements was revealed in the composition of the rich and diverse ore mineralization in the samples studied. It can be argued that a new type of mineralization was discovered for the SG-3 rocks: noble metal (Au–Ag–Pd) rare-element (Bi–Te).

Based on the geographical atlases of the 16th century, the German scientist G. Leibniz proposed to Peter I a project aimed at discovering a strait between Asia and America, studying the Earth’s magnetic field, cartographic and other research in Russia. In December 1724, Peter I signed a decree on equipping the expedition, which was called the First Kamchatka Expedition (1725–1730). In 1732, the expedition of I. Fedorov and M.S. Gvozdev through the Bering Strait approached the northwestern coast of America in the area of Cape Gvozdev (now — Cape Prince of Wales). At the same time, members of the Admiralty Board N.F. Golovin and T. Sanders proposed organizing Russian round-the-world voyages and creating a Pacific Fleet to protect Russia's Far Eastern borders. In 1741, the Second Kamchatka Expedition of V.I. Bering and A.I. Chirikov explored the northwestern coast of America and the islands of the Aleutian ridge. In 1763, M.V. Lomonosov justified the possibility of passing the Northern Sea Route through the Pole to Kamchatka. In 1764–1769, by the order of Catherine II, K. Krenitsyn and M.D. Levashov sent a secret expedition to the Bering Strait, which initiated a systematic mapping of the Aleutian Islands and Alaska. The expedition of I. Billings and G.A. Sarychev (1785–1796) resulted in the publication of maps of the Pacific Ocean. By the beginning of the 19th century, the question of the sea route to the Atlantic from the Bering Sea through the Arctic Ocean remained open. I.F. Kruzenshtern developed his own plan for organizing round-the-world voyages and received state support. Emperor Alexander I granted the request of the head of the Russian-American Company, N.P. Rezanov about sending goods to the Pacific colonies by sea and establishing interstate relations with Japan, which made it possible to equip the first Russian round-the-world expedition under the command of I.F. Kruzenshtern and Yu.F. Lisyanskiy (1803–1806).

Individual fluid inclusions with dense carbon dioxide hosted in quartz from the gold-bearing interval penetrated by the SD-3 Kola Superdeep Borehole were studied using modern techniques. The composition and density of the carbon dioxide fluid were determined by Raman spectroscopy and microthermometry. The density of the fluid is 0.37–1.14 g/cm³ and contains minor admixtures of nitrogen (0.3–1.8 mol %) and water (0.1–0.4 mol %). LA-ICP-MS data indicate that the carbon dioxide fluid inclusions contain high concentrations of Au (1–2611 ppm) and Ag (1–4389 ppm), and high-precision optical data indicate that the high-density CO₂ fluid of the inclusions contains Au–Ag nanoparticles. Evidently, gold and silver were transported from the Earth’s mantle to the crust by high-density carbon dioxide fluid in the form of nanoparticles.