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Towards functional characterization of archaeal genomic dark matter.

ABSTRACT: A substantial fraction of archaeal genes, from ?30% to as much as 80%, encode 'hypothetical' proteins or genomic 'dark matter'. Archaeal genomes typically contain a higher fraction of dark matter compared with bacterial genomes, primarily, because isolation and cultivation of most archaea in the laboratory, and accordingly, experimental characterization of archaeal genes, are difficult. In the present study, we present quantitative characteristics of the archaeal genomic dark matter and discuss comparative genomic approaches for functional prediction for 'hypothetical' proteins. We propose a list of top priority candidates for experimental characterization with a broad distribution among archaea and those that are characteristic of poorly studied major archaeal groups such as Thaumarchaea, DPANN (Diapherotrites, Parvarchaeota, Aenigmarchaeota, Nanoarchaeota and Nanohaloarchaeota) and Asgard.

SUBMITTER: Makarova KS

PROVIDER: S-EPMC6393860 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

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Towards functional characterization of archaeal genomic dark matter.

Makarova Kira S KS Wolf Yuri I YI Koonin Eugene V EV

Biochemical Society transactions 20190201 1

A substantial fraction of archaeal genes, from ∼30% to as much as 80%, encode 'hypothetical' proteins or genomic 'dark matter'. Archaeal genomes typically contain a higher fraction of dark matter compared with bacterial genomes, primarily, because isolation and cultivation of most archaea in the laboratory, and accordingly, experimental characterization of archaeal genes, are difficult. In the present study, we present quantitative characteristics of the archaeal genomic dark matter and discuss ...[more]

PMID: 30710061

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