Halobacteriovorax halts disease progression in endangered Caribbean corals

Area of Science:

• Marine biology
• Microbial ecology
• Coral reef science

Background:

• Predation significantly influences ecosystem structure and evolution.
• Microbial predation's role in top-down control is understudied.
• Halobacteriovorax bacteria show potential for treating polymicrobial infections due to their prey range.

Purpose of the Study:

• To investigate the efficacy of predatory bacteria (Halobacteriovorax) in mitigating coral disease.
• To model disease dynamics in Acropora cervicornis using Vibrio coralliilyticus as a pathogen.
• To assess Halobacteriovorax as a potential therapeutic agent for coral diseases.

Main Methods:

• Infection of Acropora cervicornis with Vibrio coralliilyticus.
• Treatment of infected corals with Halobacteriovorax cultures upon disease onset.
• Monitoring coral bleaching and tissue loss over five days.

Main Results:

• Corals treated with Halobacteriovorax showed significantly reduced bleaching (57% unaffected beyond inoculation site) and no tissue loss.
• Untreated corals experienced 100% bleaching within 48 hours and 86% tissue loss within five days.
• Halobacteriovorax successfully halted the progression of Vibrio-induced disease in corals.

Conclusions:

• Predatory bacteria can act as top-down regulators in eukaryotic microbiomes.
• Halobacteriovorax demonstrates potential as a living probiotic therapy for coral diseases.
• Microbial predators represent a promising avenue for coral reef conservation and disease management.