Comparative genomics analyses of Actinobacteriota identify Golgi phosphoprotein 3 (GPP34) as a widespread ancient protein family associated with sponge symbiosis.

Background: Sponges harbor microbial communities that play crucial roles in host health and ecology. However, the genetic adaptations that enable these symbiotic microorganisms to thrive within the sponge environment are still being elucidated. To understand these genetic adaptations, we conducted a comparative genomics analysis on 350 genomes of Actinobacteriota, a phylum commonly associated with sponges.

Rhodopsin-mediated nutrient uptake by cultivated photoheterotrophic Verrucomicrobiota.

Rhodopsin photosystems convert light energy into electrochemical gradients used by the cell to produce ATP, or for other energy-demanding processes. While these photosystems are widespread in the ocean and have been identified in diverse microbial taxonomic groups, their physiological role in vivo has only been studied in few marine bacterial strains. Recent metagenomic studies revealed the presence of rhodopsin genes in the understudied Verrucomicrobiota phylum, yet their distribution within different Verrucomicrobiota lineages, their diversity, and function remain unknown.

Functional characterization and taxonomic classification of novel gammaproteobacterial diversity in sponges.

Sponges harbour exceptionally diverse microbial communities, whose members are largely uncultured. The class Gammaproteobacteria often dominates the microbial communities of various sponge species, but most of its diversity remains functional and taxonomically uncharacterised. Here we reconstructed and characterised 32 metagenome-assembled genomes (MAGs) derived from three sponge species.

Spatiotemporal Variation of Microbial Communities in the Ultra-Oligotrophic Eastern Mediterranean Sea.

Marine microbial communities vary seasonally and spatially, but these two factors are rarely addressed together. In this study, the temporal and spatial patterns of the bacterial and archaeal community were studied along a coast-to-offshore transect in the Eastern Mediterranean Sea (EMS) over six cruises, in three seasons of 2 consecutive years. Amplicon sequencing of 16S rRNA genes and transcripts was performed to determine presence and activity, respectively.