Haliea rubra CM41_15aT was deposited in the DSMZ by the Laboratoire
Arago, Université Pierre et Marie Curie (Banyuls-sur-mer, France) under the conditions of a Material Transfer Agreement. The authenticity of the used strains has been confirmed by the Identification Service of the Selleckchem mTOR inhibitor DSMZ by sequencing of the respective 16S rRNA genes. For routine cultivation all strains were grown on Marine Broth or Agar 2216. The BChl a-containing strains Ivo14T, DSM 17192T, DSM 19751T and DSM 23344T were also grown in a complex medium that was less nutrient-rich and more suitable for the expression of photosynthetic pigments in these strains. It was designated SYPHC medium and has the following composition (per liter demineralized water): 35.00 g sea salts, 0.10 g NH4Cl, 0.05 g KH2PO4, 2.50 g HEPES (4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid), 1.00 g
yeast extract, 1.10 g sodium pyruvate, 0.04 g L-histidine, 0.04 g L-cysteine-HCl × H2O, 1.00 ml Wolfe’s mineral elixir (see DSMZ medium 792) [58], and 1.00 ml vitamins solution (see DSMZ medium 503) [58]. All ingredients were dissolved in water except NH4Cl and KH2PO4, which were added after autoclaving from a sterile stock solution. The pH of the medium was adjusted to 7.5 – 7.7 prior to autoclaving. For incubation of cultures in closed serum vials under defined gas atmospheres the SYPHC medium was slightly modified: All compounds, except the HEPES buffer Telomerase which was omitted, were dissolved in water and then the solution was sparged with a 80% N2 and 20% CO2 gas mixture for 45 min to remove dissolved Rabusertib in vitro oxygen. Various concentrations of oxygen in the headspace gas atmosphere were obtained by filling serum vials with anoxic medium to certain levels as described previously [8]. The pH of the medium was adjusted to 7.3 – 7.5 after autoclaving by adding Na2CO3 from a sterile and anoxic stock solution (5% w/v) that was prepared
under a 80% N2 and 20% CO2 gas atmosphere. In some experiments the sodium pyruvate in SYPHC medium was replaced with sodium DL-malate and the resulting medium was designated SYMHC or SYM, if the amino acids L-histidine and L-cysteine were omitted. All chemicals were obtained from Sigma-Aldrich (Taufkirchen, Germany) and complex nutrients from DIFCO BBL (Becton Dickinson; Heidelberg, Germany). Determination of growth and phenotypic traits The absorbance values of growing cultures were determined in a Thermo Scientific BioMate 6 split beam UV/visible spectrophotometer using 1 cm light path disposable cuvettes and water as blank. The CX-6258 mw A660nm reading was used to estimate the cell density. Expression of the light-harvesting complex in strain Ivo14T was estimated by determining the A870nm to A660nm ratio, whereas for cultures of C. litoralis and Chromatocurvus halotolerans a ratio of A880nm to A660nm was used and for H. rubra a ratio of A820nm to A660nm.