HKUST researchers find new symbiotic organelle in deep-sea worm

New structure found in glistenworm

This research examined Chaetoderma shenloong, which is alternatively called the Divine Dragon Glistenworm. This animal lives at cold seeps in the South China Sea where oxygen is nearly absent. The team led by Qian Pei-Yuan identified a specialized organelle that maintains bacterial symbiosis. These spherical structures measure between 10 and 15 micrometers in diameter. Each sphere wraps around hundreds of bacteria with more than 20 membrane layers.

Worm adapts to extreme depths

This mollusk lives within sediment deposits located tens of centimeters below the ocean floor. These mud layers contain almost no oxygen but are rich in hydrogen sulfide. The digestive system differs significantly from typical mollusks with a heavily reduced radula. Instead, most of its body cavity is filled by a highly developed digestive gland system. This adaptation allows survival without sunlight by relying on chemosynthetic bacteria for energy.

Study published in Nature journal

The findings appear in the journal Nature Communications under a specific title regarding aplacophoran molluscs. Collaboration included Sun Jin from the Ocean University of China and Qiu Jian-Wen from Hong Kong Baptist University. The research team used micro-computed tomography and three-dimensional image reconstruction technology for analysis. This discovery offers new insights into organelle evolution and deep-sea ecosystem adaptation mechanisms.