High-resolution ultrastructure and morphology of marine ammonia-oxidizing archaea Nitrosopumilus maritimus SCM1 revealed by Cryo-ET and STEM-EDS

Zhou, Y.; Yan, A.; Yang, J.; He, W.; Guo, S.; Li, Y.; Dai, Y.; Pan, X.; Cui, D.; Teng, W.; Pereira, O.; Bi, R.; Chen, S.; Fan, L.; Wang, P.; Liao, Y.; Qin, W.; Sui, S.-F.; Zhu, Y.; Zhang, C.; Liu, Z.

doi:10.1101/2023.12.12.571259

bioRxiv · 10.1101/2023.12.12.571259

High-resolution ultrastructure and morphology of marine ammonia-oxidizing archaea Nitrosopumilus maritimus SCM1 revealed by Cryo-ET and STEM-EDS

Zhou, Y.·Yan, A.·Yang, J.·He, W.·Guo, S.·Li, Y.·Dai, Y.·Pan, X.·Cui, D.·Teng, W.·Pereira, O.·Bi, R.·Chen, S.·Fan, L.·Wang, P.·Liao, Y.·Qin, W.·Sui, S.-F.·Zhu, Y.·Zhang, C.·Liu, Z.

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Abstract

Nitrososphaerota, formerly known as Thaumarchaeota, constitute a diverse and widespread group of ammonia-oxidizing archaea (AOA) inhabiting ubiquitously in marine and terrestrial environments, playing a pivotal role in global nitrogen cycling. Despite their significance in Earths ecosystems, the cellular organization of AOA remains largely unexplored, leading to a significant question unanswered of how the machinery of these organisms underpins metabolic functions. In this study, we combined chromatic-aberration-corrected cryo-electron tomography (cryo-ET), scanning transmission electron microscopy (STEM), and energy dispersive X-ray spectroscopy (EDS) to unveil the cellular organization and elemental composition of Nitrosopumilus maritimus SCM1, a representative member of marine Nitrososphaerota. Our tomograms show the native ultrastructural morphology of SCM1 and one to several dense storage granules in the cytoplasm. STEM-EDS analysis identifies two types of storage granules in which one type is possibly composed of polyphosphate, while the other type is polyhydroxyalkanoate. Collectively, these findings provide visual evidence for the resilience of AOA in the vast oligotrophic marine environment.

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Zhou, Y., Yan, A., Yang, J., He, W., Guo, S., Li, Y., Dai, Y., Pan, X., Cui, D., Teng, W., Pereira, O., Bi, R., Chen, S., Fan, L., Wang, P., Liao, Y., Qin, W., Sui, S.-F., Zhu, Y., Zhang, C., Liu, Z.. 2023-12-12. High-resolution ultrastructure and morphology of marine ammonia-oxidizing archaea Nitrosopumilus maritimus SCM1 revealed by Cryo-ET and STEM-EDS. https://doi.org/10.1101/2023.12.12.571259

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