Sulfate-Reducing Bacteria That Produce Exopolymers Thrive in the Calcifying Zone of a Hypersaline Cyanobacterial Mat

In this study, we report the phenotypic and genomic characteristics of the novel strain and correlate these traits with a possible function in the biogeochemistry of the studied microbial mat. Materials and Methods Strains and Cultivation Conditions Strain L21-Syr-ABT was isolated from an anaerobic enrichment culture with syringate as substrate, inoculated with slurries of a cyanobacterial mat sample retrieved from the hypersaline Lake 21 on the Kiritimati Atoll (Northern Line Islands, Republic of Kiribati). The location of the sampling site and details of the isolation procedure were described previously (Spring et al., 2015a). For the preparation of media and incubation under anoxic conditions the anaerobe cultivation technique of Hungate (1950) with the modifications introduced by Bryant (1972) was used. For routine cultivation of strain L21-Syr-ABT the medium DSM 1526c was used that contained per liter deionized ultrapure water: 60.0 g NaCl, 6.0 g MgSO4 × 7 H2O, 1.5 g KCl, 1.0 g Na2S2O3 × 5 H2O, 1.0 g NH4Cl, 0.4 g CaCl2 × 2 H2O, 0.4 g K2HPO4, 10.0 ml trace elements solution of DSMZ medium 1411, 1.0 g yeast extract, 0.5 mg resazurin, 10.0 ml vitamins solution of DSMZ medium 141, 1.5 g Na2CO3, 2.5 g sodium pyruvate, and 0.5 g Na2S × 9 H2O. The medium was prepared under 80% N2 and 20% CO2 gas mixture without the vitamins, carbonate, sodium pyruvate and sulfide, which were added to the medium after autoclaving from sterile anoxic stock solutions...
Source: Frontiers in Microbiology - Category: Microbiology Source Type: research