A hyphen indicates that the branch was not obtained with the respective reconstruction method. Nucleotide sequence accession numbers are given in parentheses. The affiliation of strains to subclades of the OM60/NOR5 group is based on [13]. The sequence of Alcanivorax borkumensis [GenBank:Y12579] was used as outgroup (not shown). Designations given in red color indicate that the respective strains produce BChl a and/or encode genes for a photosynthetic apparatus; names in blue indicate the presence of proteorhodopsin encoding genes. Strains that were tested with specific PCR primers for the presence of pufLM and soxB genes are labeled with red and yellow circles,

respectively. Closed circles indicate a positive PCR reaction and open circles a negative reaction. The bar represents an estimated sequence divergence of 5%. It was not possible to amplify genes encoding proteorhodopsin Saracatinib or the sulfate thiol esterase SoxB from the non-phototrophic species shown in Figure  1. For the PCR screening with

the proteorhodopsin primer set PR1-3 [26] we used genomic DNA from Dokdonia sp. PRO95 [27] as well as total DNA isolated from the North Sea as positive control. However, a proteorhodopsin-positive control strain belonging to this phylogenetic group was not available and the pop gene sequence of strain IMCC3088 revealed some mismatches to the used proteorhodopsin oligonucleotide primers. Thus, either the tested strains do not encode pop genes, or the genes are such different at the primer binding sites that no PCR amplification was possible. Phenotypic characterization Morphology selleck chemicals of cells and colonies Size and shape of cells of the newly isolated not strain Ivo14T were determined upon growth in SYPHC medium, which was optimal for cultivation of this strain and the related species C. litoralis, H. rubra and Chromatocurvus halotolerans. Cells of Ivo14T were non motile and appeared

coccoid or as short straight-to-bent rods. Occurrence of pleomorphic cells was observed in all four BChl a-containing strains and depended to some extent on the composition of the growth medium, which makes it important to use the same medium for comparison of size and shape. Especially, growth on the nutrient-rich medium Marine Broth 2216 led in cultures of H. rubra, C. litoralis and Chromatocurvus learn more halotolerans to cells with irregular shapes, swelling of cells and accumulation of highly refractile storage compounds, whereas these effects were less pronounced in cultures of Ivo14T. The storage compound cyanophycin, which is a characteristic of C. litoralis was not detected in cells of Ivo14T or Chromatocurvus halotolerans, which both accumulate polyhydroxyalkanoates in addition to polyphosphates. The intracellular carbon storage compound of H. rubra could be distinguished from cyanophycin or polyhydroxyalkanoates by a positive reaction of the acidified cell extract with the anthrone reagent, which detects carbohydrates.