Project's information

Project's title Molecular approach to the study of biodiversity of symbiotic dinoflagellates of Vietnam corals
Project’s code QTRU01.10/21-22
Research hosting institution Institute of Natural Products Chemistry
Coordinating unit, co-chair Far East Branch of the Russian Academy of Sciences (FEB RAS)
Project leader’s name Dr. Dang Thi Phuong Ly and Dr. Tatyana V. Sikorskaya
Project duration 01/05/2021 - 31/05/2023
Project’s budget 200 million VND
Classify Excellent
Goal and objectives of the project

- Collecting samples and conducting lipid studies, analyzing the molecular species of lipid classes of 3 coral species containing symbiotic microalgae collected in the East Vietnam Sea (3 species representing hard coral, soft coral and hydrocoral).
- Cooperate with Russian partners to isolate the symbiotic microalgae, analyze the biodiversity of the symbiotic microalgae present in the collected samples, study lipids of symbiotic microalgae and molecular species of lipid classes of symbiotic microalgae present in 3 collected coral samples.

Main results

- Research:
The project conducted studies 15 samples belonging to 3 coral species Acropora sp., S. flexibilis and M. platyphylla. Data on total lipid content, lipid composition in total lipid, composition and content of fatty acids in coral/hydrocoral samples were collected. The results of genetic analysis determining the diversity of endosymbionts in coral/hydrocoral samples showed the presence of Symbiodiniaceae in all samples belonging to Acropora sp. and M. platyphylla and in three samples of S. flexibilis. The thylakoid lipidome (mono- and digalactosyldiacylglycerol (MGDG and DGDG), sulfoquinovosyldiacylglycerol (SQDG) and phosphatidylglycerol (PG)) of total lipids from three coral species were analyzed and compared. Lipids of S. flexibilis are characterized by very high SQDG/PG ratio, DGDG/MGDG ratio < 1, lower degree of galactolipid unsaturation, higher SQDG content with polyunsaturated fatty acids and thinner thylakoid membranes could be explained by the presence of the heat-inducible diatoms Cladocopium C3. In contrast, lipids of M. platyphylla and Acropora sp. exhibits lipidome features of heat-resistant Symbiodiniaceae. The colonies of M. platyphylla and Acropora sp. contain the symbionts Cladocopium C3u and Cladocopium C71/C71a, respectively, and their lipidome profiles show features of heat tolerance. The association with symbionts exhibiting heat-tolerant thylakoid lipidome characteristics, combined with high Symbiodiniaceae diversity, may facilitate further acclimatization/adaptation of coral symbionts. M. platyphylla and Acropora sp. in the East Vietnam Sea.
- International Cooperation:
With the support of equipments and modern analysis methods from Russian experts, the project has welcomed 01 trip for scientific exchange (05/2023), contributing to promoting the traditional bilateral cooperation between two organizations.
From the obtained results, the scientists from both side have published 01 international journal (SCIE), 01 domestic journal (Accepted).
- Training: a Graduated Science Master

Novelty and actuality and scientific meaningfulness of the results

Genetic methods have become a standard, widely accepted approach to identifying organisms. However, lipid analysis is an additional independent method providing important results that are comparable with similar works based exclusively on analysis of FA profiles and occurrence of FAs in different lipid classes (lipidome). The use of a lipid profile as a chemotaxonomic biomarker alongside molecular genetics analyses can provide additional information on specific lipid compositions. Such polyphasic analysis can reveal new reliable chemotaxonomic markers for differentiating symbionts on a low taxonomic scale. Most likely, the thylakoid membrane lipidome is determined by the major symbiont species. Features of S. flexibilis such as a very high SQDG/PG ratio, a DGDG/MGDG ratio < 1, the lowest degree of galactolipid unsaturation, a higher content of SQDG with PUFAs, and a thinner thylakoid membrane may be explained by the presence of the thermosensitive dinoflagellate species Cladocopium C3. In contrast, symbionts of M. platyphylla and Acropora sp. exhibited thermotolerant lipidome features. Since each colony of M. platyphylla and Acropora sp. contained Cladocopium C3u and Cladocopium C71/C71a, respectively, these species could be responsible for the expression of thermotolerant lipidome features. Thus, there may be significant differences in thylakoid lipidome among the Symbiodiniaceae species within the same genus, likely associated with light affinity and temperature tolerance. In the future, a comprehensive comparative study of the thylakoid membrane structure and properties in symbionts at the intraspecific taxonomic level is necessary to fully understand the thylakoid lipidome features responsible for variations in thermotolerance.

Products of the project

- Publications: 
- Tatyana V. Sikorskaya, Ekaterina V. Ermolenko, Kseniya V. Efimova and Ly T. P. Dang; Coral Holobionts Possess Distinct Lipid Profiles That May Be Shaped by Symbiodiniaceae Taxonomy. Mar. Drugs 2022, 20, 485. 
- Dao Thi Kim Dung, Dang Thi Phuong Ly, Dang Thi Minh Tuyet, Nguyen Thi Nga, Pham Quoc Long (2023). Diversity of fatty acids in different coral species collected in the sea of Nha Trang, Khanh Hoa. Vietnam Journal of Marine Science and Technology (Accepted)


This study conducted research at the very beginning with the minimum number of species collected. The project leader and team wish to continue this research direction in the next phase with more coral species to be collected.

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