Isotopic Signatures of Carbon Transfer in a Proterozoic Analogue Microbial Mat.

ABSTRACT: Modern microbial mats are potential analogues for Proterozoic ecosystems, yet only a few studies have characterized mats under low-oxygen conditions that are relevant to Proterozoic environments. Here, we use protein-stable isotope fingerprinting (P-SIF) to determine the protein carbon isotope (δ¹³C) values of autotrophic, heterotrophic, and mixotrophic organisms in a benthic microbial mat from the low-oxygen Middle Island Sinkhole, Lake Huron, USA (MIS). We also measure the δ¹³C values of the sugar moieties of exopolysaccharides (EPS) within the mat to explore the relationships between cyanobacterial exudates and heterotrophic anabolic carbon uptake. Our results show that Cyanobacteria (autotrophs) are ¹³C-depleted, relative to sulfate-reducing bacteria (h

SUBMITTER: Gonzalez-Nayeck AC 

PROVIDER: S-EPMC10231192 | biostudies-literature | 2023 May

REPOSITORIES: biostudies-literature