Carotenoid biomarkers in Namibian shelf sediments: Anoxygenic photosynthesis during sulfide eruptions in the Benguela Upwelling System.

ABSTRACT: Aromatic carotenoid-derived hydrocarbon biomarkers are ubiquitous in ancient sediments and oils and are typically attributed to anoxygenic phototrophic green sulfur bacteria (GSB) and purple sulfur bacteria (PSB). These biomarkers serve as proxies for the environmental growth requirements of PSB and GSB, namely euxinic waters extending into the photic zone. Until now, prevailing models for environments supporting anoxygenic phototrophs include microbial mats, restricted basins and fjords with deep chemoclines, and meromictic lakes with shallow chemoclines. However, carotenoids have been reported in ancient open marine settings for which there currently are no known modern analogs that host GSB and PSB. The Benguela Upwelling System offshore Namibia, known for exceptionally high primary pro

SUBMITTER: Ma J 

PROVIDER: S-EPMC8307692 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature