RT Journal Article
SR Electronic
T1 Microbial community dynamics and coexistence in a sulfide-driven phototrophic bloom
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 604504
DO 10.1101/604504
A1 Srijak Bhatnagar
A1 Elise S. Cowley
A1 Sebastian H. Kopf
A1 Sherlynette Pérez Castro
A1 Sean Kearney
A1 Scott C. Dawson
A1 Kurt Hanselmann
A1 S. Emil Ruff
YR 2019
UL http://biorxiv.org/content/early/2019/04/10/604504.abstract
AB Phototrophic microbial mats commonly contain multiple phototrophic lineages that coexist based on their light, oxygen and nutrient preferences. Here we show that similar coexistence patterns and ecological niches can occur in suspended phototrophic blooms of an organic-rich estuary. The water column showed steep gradients of oxygen, pH, sulfate, sulfide, and salinity. The upper part of the bloom was dominated by aerobic phototrophic Cyanobacteria, the middle and lower parts were dominated by anoxygenic purple sulfur bacteria (Chromatiales) and green sulfur bacteria (Chlorobiales), respectively. We found multiple uncultured phototrophic lineages and present metagenome-assembled genomes of two uncultured organisms within the Chlorobiales. Apparently, those Chlorobiales populations were affected by Microviridae viruses. We suggest a cryptic sulfur cycle within the bloom in which elemental sulfur produced by phototrophs is reduced to sulfide by Desulfuromonas sp. These findings improve our understanding of the ecology and ecophysiology of phototrophic blooms and their impact on biogeochemical cycles.