Host-associated microbial communities have an important role in shaping the health and fitness of plants and animals. Most studies have focused on the bacterial, fungal or viral communities, but often the archaeal component has been neglected. The archaeal community, the so-called archaeome, is now increasingly recognized as an important component of host-associated microbiomes. It is composed of various lineages, including mainly Methanobacteriales and Methanomassiliicoccales (Euryarchaeota), as well as representatives of the Thaumarchaeota. Host–archaeome interactions have mostly been delineated from methanogenic archaea in the gastrointestinal tract, where they contribute to substantial methane production and are potentially also involved in disease-relevant processes. In this Review, we discuss the diversity and potential roles of the archaea associated with protists, plants and animals. We also present the current understanding of the archaeome in humans, the specific adaptations involved in interaction with the resident microbial community as well as with the host, and the roles of the archaeome in both health and disease.

宿主相关微生物群落在塑造植物和动物的健康和适应性方面具有重要作用。大多数研究都集中在细菌、真菌或病毒群落上，但古细菌成分往往被忽视。古菌群落，即所谓的古菌群，现在越来越被认为是宿主相关微生物群落的重要组成部分。它由各种谱系组成，主要包括甲烷菌目和甲烷菌目（广古菌门），以及奇古菌门的代表。宿主-古生菌的相互作用主要是从胃肠道中的产甲烷古菌中描述出来的，它们有助于大量甲烷的产生，并且还可能参与与疾病相关的过程。在这篇评论中，我们讨论了与原生生物、植物和动物相关的古生菌的多样性和潜在作用。我们还介绍了目前对人类古生菌的理解、与常驻微生物群落以及宿主相互作用所涉及的特定适应性，以及古生菌在健康和疾病中的作用。