Observations on a magnetotactic bacteria-grazing ciliate in sediment from the intertidal zone of Huiquan Bay, China

Magnetotactic bacteria(MTB) are a group of prokaryotes having the ability to orient and swim along geomagnetic fi eld lines because they contain intracellular magnetosomes that synthesized through biomineralization process. Magnetosomes have recently also been found in unicellular eukaryotes, which referred as magnetically responsive protists(MRPs). The three origins MRPs. In this study, we characterized MTB-grazing ciliated MRP was collected from intertidal sediment Huiquan Bay, Qingdao, China. Based on 18S rRNA gene sequence analysis, tentatively identifi ed Uronemella parafi lificum HQ. Using transmission electron microscopy, observed 2-3 shapes were randomly distributed within ciliate. Energydispersive X-ray spectroscopy high-resolution microscopy images consistent with them being composed magnetite. same shape mineral composition detected MTB occurred environment MRP. Statistical analysis showed size similar those MTB. results suggest can graze, ingest, digest various types It is certainly worth noting rst record MRPs Asian aquatic suggesting might be widely distributed. These support assertion probably contribute ecological cycles iron, expand possibilities for research into mechanism magnetoreception eukaryotes.