Biologiya Morya

This review presents current information on the diversity of bacterial enzyme systems involved in the aerobic and anaerobic oxidation of aliphatic and aromatic hydrocarbons in oil. It is shown that the most common hydrocarbon-oxidizing microorganisms in the marine environment include bacteria of the genera Mycobacterium, Brevibacterium, Nocardia, Corynebacterium, Rhodococcus, and Arthrobacter, which are usually isolated from areas with severe oil pollution. Alcanivorax, Acinetobacter, Achromobacter, Bacterium, Bacillus, Micrococcus, Pseudomonas, Pseudoalteromonas, Psychrobacter, Marinobacter, Marinomonas, Halomonas, Oleispira, Thalassolituus, Oleiphilus, and Shewanella are often mentioned among marine oil oxidizers. Information continues to appear on bacterial taxa for which hydrocarbon-oxidizing activity is described for the first time. Currently, most studies in this area focused on either to areas of chronic petroleum hydrocarbon pollution or to poorly studied areas, including deep-sea sites. Of particular interest is the feasibility of using microbial potential for the bioremediation of oil-polluted water areas, especially under anaerobic conditions.

The development of melanin pigmentation is described in larvae of the Pacific sand lance Ammodytes hexapterus Pallas, 1814 from Peter the Great Bay, identified according to phylogenetic analysis using the cytochrome c oxidase subunit I gene of mtDNA. No fundamental differences in the surface pigmentation of A. japonicus larvae collected in the Yellow Sea and those of A. heian collected in the Sea of Japan are found, either in the number of elements or in the time and pattern of larvae development. The presence of the internal row of melanophores located above the notochord is shown, which becomes already evident at the flexion stage and is clearly visible on living material of A. hexapterus juveniles. It was not previously noted for any of the considered species of the genus. One can conclude that melanin pigmentation of A. hexapterus larvae is not significantly different from that of larvae of other species belonging to this genus from the Sea of Japan. Therefore, melanin pigmentation alone cannot be used for reliable identification without the use of countable characteristics, such as the number of myomers or vertebrae at later stages, which have previously shown more distinct differences.

Calyptogena pacifica (Bivalvia: Vesicomyidae: Pliocardiinae) is an amphi-Pacific, bathyal, chemosymbiotic species living near cold methane seeps, hydrothermal vents, and cetacean carcasses. In the present study, the genetic diversity of C. pacifica on the scale of the entire geographic range of the species is addressed for the first time, using a sequence of the cytochrome c oxidase subunit I (COI) gene. The material includes both own data obtained during a study of bivalve mollusks from the Koryak slope and the Piip Volcano, Bering Sea, and information on COI sequences of bivalves from five East Pacific regions published in GenBank. A total of 12 haplotypes have been identified, of which two are from both the West Pacific (Bering Sea) and the East Pacific, one only from the West Pacific, and nine only from the East Pacific. The results of analysis of molecular variance have not revealed significant genetic differences both between the samples from the Koryak slope and the Piip Volcano and between the combined samples from the West and East Pacific. Both groups of haplotypes, identified by the phylogenetic analysis, are not associated with any geographical area. The obtained data suggests no significant genetic differentiation of C. pacifica populations from the Bering Sea and the East Pacific in COI despite the spatial isolation of the habitats suitable for this bivalve mollusk.

Mating individuals of the helmet crab Telmessus cheiragonus were found during scuba diving in Taui Bay, Sea of Okhotsk, in September 2024. Mating occurred within depths 0.6–10 m and at a water temperature of 8–9°C. The largest crab aggregations were observed at a depth of 2.5–2.8 m in the macrophyte zone. The minimum carapace width in functionally mature males was 84 mm; in females, it was 48 mm. The ratio of females to males found during the study was 1:1.8 in general.