We revealed that DPANN YN1 is deficient in essential metabolic processes and requires host resources to proliferate. CryoET revealed an enormous attachment organelle in the DPANN envelope that bridges the DPANN and host cytoplasms for intercellular exchange.

Delighted to share our recent manuscript on DPANN archaea: ❄️🔬🦠 A quick thread below.

DPANN archaea form one of the most enigmatic groups in microbial ecosystems and account for ~half of all the archaeal diversity. DPANNs are characterized by their small size, reduced genome, limited metabolic capabilities and mostly symbiotic existence.

Despite their widespread occurrence and significant role in microbial ecology, very little is known about their cell biology, metabolic potential, and symbiosis. The major challenge being DPANNs are extremely hard to isolate and culture.

Here we isolated and cultivated a co-culture system of a novel DPANN (Nanobdellota archaeon YN1) and its host Sulfurisphaera ohwakuensis, and characterized it by metagenomics and metabolic pathway analysis, fLM, and CryoET.

Intriguingly, we found DPANNs in isolation too. Possibly DPANNs have two distinct life stages 1) attached with the host, 2) free from the host. The attachment organelle could allow free DPANNs to reattach and fuel up from a host – just like a car in a gas station.

We also showed that a long filament assembles at the tip of the attachment organelle and is injected/extended into the host cytoplasm. What does it mean? We do not know! This study further highlights the fascinating cell biology of underexplored archaeal cells.

Also, see a parallel manuscript from the @PilhoferLab, just accepted at ISME J. @UniMelb, @CCeMMP, @UniMelbMDHS, @Dr_MDJohnson @DoulinShepherd @PaulBindusmita @ManasiArcot @HiroyukiSakai @NorioKurosawa

Beautiful images and amazing rendering Debnath 👏👏!

Many thanks Brendan!