Evaluating the coral microbiome during cryopreservation.

Area of Science:

• Marine Biology
• Microbiology
• Conservation Science

Background:

• Coral reefs face significant threats from climate change and anthropogenic stressors.
• Coral cryopreservation is a potential strategy for conserving threatened coral diversity.
• The coral microbiome plays a crucial role in host health, but its response to cryopreservation is unknown.

Purpose of the Study:

• To investigate the impact of cryopreservation on the coral-associated bacterial communities of Porites compressa.
• To identify changes in microbiome composition during the isochoric vitrification process.
• To inform strategies for reducing cryopreservation-induced stress and improving coral husbandry.

Main Methods:

• Characterization of the microbiome of Hawaiian finger coral (Porites compressa) in the wild.
• Analysis of microbial communities at seven stages of the isochoric vitrification process.
• 16S rRNA gene sequencing to assess bacterial community composition and relative abundance.

Main Results:

• Wild P. compressa microbiomes were dominated by Endozoicomonadaceae (76.5%).
• Endozoicomonadaceae abundance decreased significantly in captivity (<6.9%) and after isochoric vitrification (<0.5%).
• Vibrionaceae became dominant post-thaw (58.5-74.7%), suggesting dysbiosis.

Conclusions:

• The capture and cryopreservation process induces coral microbiome dysbiosis.
• Cryopreservation leads to a loss of beneficial symbionts and an increase in potential pathogens.
• Probiotic restoration treatments could mitigate cryopreservation stress and enhance post-thaw coral survival.