- Extended genome report
- Open Access
Genome sequence of Planktotalea frisia type strain (SH6-1T), a representative of the Roseobacter group isolated from the North Sea during a phytoplankton bloom
Standards in Genomic Sciences volume 13, Article number: 7 (2018)
Planktotalea frisia SH6-1T Hahnke et al. (Int J Syst Evol Microbiol 62:1619–24, 2012) is a planktonic marine bacterium isolated during a phytoplankton bloom from the southern North Sea. It belongs to the Roseobacter group within the alphaproteobacterial family Rhodobacteraceae. Here we describe the draft genome sequence and annotation of the type strain SH6-1T. The genome comprises 4,106,736 bp and contains 4128 protein-coding and 38 RNA genes. The draft genome sequence provides evidence for at least three extrachromosomal elements, encodes genes for DMSP utilization, quorum sensing, photoheterotrophy and a type IV secretion system. This indicates not only adaptation to a free-living lifestyle of P. frisia but points also to interactions with prokaryotic or eukaryotic organisms.
The Roseobacter group features a global distribution in marine ecosystems like the water column and biological surfaces comprising up to 25% of marine microbial communities [1,2,3]. Members of this group exhibit numerous metabolic capabilities; besides aerobic anoxygenic photosynthesis and the production of bacteriochlorophyll a, they are also capable of oxidizing carbon monoxide, degrading aromatic compounds and catabolizing organic sulfur compounds . Some representatives of this group are also able to synthesize secondary metabolites and to produce quorum sensing molecules like acylated homoserine lactones [5,6,7]. Genomic analysis showed that almost half of the marine Roseobacter genomes encode a type IV secretion system , thus, assuming to play a role in interactions of bacteria with other prokaryotic and eukaryotic cells including phytoplankton .
A recent study on genomic contents of the Roseobacter group identified a cluster of eight purely pelagic roseobacters which are distinct from the other members of this group . One member of this cluster is strain HTCC2083, isolated from the coastal northwest Pacific Ocean . Planktotalea frisia , the type species of the genus Planktotalea , is the closest relative of HTCC2083. P. frisia has been isolated from the southern North Sea, with highest abundances in spring and summer and constitutes up to 0.9% of the bacterioplankton .
In order to expand the knowledge on roseobacters prominent in marine pelagic systems we sequenced the genome of P. frisia and present the draft version together with its annotations. Even though SH6-1T was originally allocated to the free-living fraction , experimental studies in which SH6-1T was grown in presence of axenic algae cultures suggested specific interactions with different phytoplankton species. Furthermore, this representative of the Roseobacter group occurred mainly free-living during a phytoplankton bloom in the North Sea but also in the particle-associated fraction after the breakdown of a Phaeocystis bloom . Thus, our special focus was on genomic features related to the lifestyle of this organism and we had a closer look on genes involved in sulfur cycling such as degradation of dimethylsulfoniopropionate and genes indicating biofilm formation, motility, chemotaxis and quorum sensing pointing to a surface-attached lifestyle.
Classification and features
Figure 1 shows the phylogenetic neighborhood of P. frisia DSM 23709T in a 16S rRNA gene sequence-based tree analyzed using NCBI-BLAST  and ARB . The sequence of the single 16S rRNA gene copy in the genome does not differ from the previously published 16S rRNA gene sequence (FJ882052).
Cells of P. frisia SH6-1T are Gram-negative irregular rods with a width of 0.4 to 1 μm and a length of 0.5 to 4 μm (Fig. 2) . On seawater agar colonies are small, circular, convex and whitish with a shiny surface. SH6-1T is a marine, aerobic bacterium with a temperature range of 4–32 °C and an optimum growth rate at 20–25 °C. The salinity range for this strain is between 1.25 and 8% NaCl. The optimal pH range for growth is 7.5–9.0 with pH 6.0 being the lowest possible pH at which growth occurs under the tested conditions.
The following carbon sources were utilized by strain SH6-1T: L-alanine, L-arginine, L-aspartic acid, L-proline, L-serine, L-tryptophan, L-tyrosine, (+)-D-xylose, (+)-D-glucose, (+)-D-mannose, (+)-D-galactose, (−)-D-fructose, (−)-D-ribose, (−)-D-mannitol, sucrose, maltose, cellobiose, trehalose, lactose, sodium acetate, sodium pyruvate, sodium malate, citric acid, disodium succinate, sodium lactate, glycerol and Tween 80 . Strain SH6-1T cannot utilize L-asparagine, L-cysteine, L-glutamine, L-glutamic acid, glycine, L-histidine, L-isoleucine, L-leucine, L-lysine, L-methionine, L-phenylalanine, L-threonine, L-valine, (+)-L-arabinose, (+)-L-rhamnose, (−)-L-fucose, (−)-D-sorbitol, (+)-D-glucosamine, laminarin, starch, inulin, xylan, sodium formate, sodium propionate and DMSP . Strain SH6-1T is susceptible to penicillin G, streptomycin sulfate and chloramphenicol, but not to kanamycin sulfate. No growth was observed in the absence of the vitamins pantothenic acid and nicotinic acid amide . A summary of the classification and features of strain SH6-1T is presented in Table 1.
The principal cellular fatty acids of strain SH6-1T are C18:1ω7c (70.97%), C18:2 (11.45%), C16:0 (6.44%), 11-Methyl C18:1ω7c (2.74%), C12:1 (2.56%), C12:1 3-OH (1.82%), C18:0 (1.75%), C10:0 3-OH (1.36%), C14:1 3-OH (0.18%) and summed feature 7 consisted of C19:1ω6c and/or unknown ECL 18.846 (0.34%) . Ubiquinone Q10 is the predominant respiratory lipoquinone of strain SH6-1T and the major polar lipids are phosphatidylcholine, phosphatidylglycerol, one unidentified aminolipid and one unidentified phospholipid .
Genome sequencing information
Genome project history
The genome was sequenced within the Collaborative Research Center “Ecology, Physiology and Molecular Biology of the Roseobacter clade: Towards a Systems Biology Understanding of a Globally Important Clade of Marine Bacteria” funded by Deutsche Forschungsgemeinschaft. The genome project was deposited in the Genomes OnLine Database  and in the Integrated Microbial Genomes database . The Whole Genome Shotgun project has been deposited at DDBJ/ENA/GenBank under the accession number MLCB00000000. The version described here is version MLCB01000000. A summary of the project information is shown in Table 2.
Growth conditions and genomic DNA preparation
A culture of SH6-1T was grown in DSMZ medium 1282 (SH Seawater medium)  at 20 °C. Genomic DNA was isolated using a Power Soil DNA Isolation kit (MoBio) following the standard protocol provided by the manufacturer but modified by the addition of 100 μl Tris for cell lysis. DNA is available from DSMZ through DNA Bank Network .
Genome sequencing and assembly
The draft genome sequence was generated using Illumina sequencing technology. For this genome, we constructed and sequenced an Illumina paired-end library with the Illumina Nextera XT library preparation kit and sequencing of the library using Genome Analyzer IIx were performed as described by the manufacturer (Illumina, San Diego, CA, USA). A total of 4.6 million paired-end reads were derived from sequencing and trimmed using Trimmomatic version 0.32 . De novo assembly of all trimmed reads with SPAdes version 3.5.0  resulted in 227 contigs and 150-fold coverage.
Genes were identified as part of the genome annotation pipeline of the Integrated Microbial Genomes (IMG-ER) platform using Prodigal v2.50 . The predicted CDS were translated used to search the CDD, KEGG, UniProt, TIGRFam, Pfam and InterPro databases. These data sources were combined to assert a product description for each predicted protein. Non-coding genes and miscellaneous features were predicted using tRNAscan-SE , RNAmmer , Rfam , TMHMM  and SignalP . Additional gene prediction analyses and functional annotation were performed within the IMG-ER platform .
The genome consists of 227 contigs with a total length of 4,106,736 bp and a G + C content of 53.77% (Table 3). Of the 4166 genes predicted, 4128 were protein-coding genes, and 38 RNA genes. No pseudogenes or CRISPR elements were found. For the majority of the protein-coding genes (78.06%) a putative function could be assigned and the others were annotated as hypothetical proteins. The genome statistics are provided in Table 3 and Fig. 3. The distribution of genes into COGs functional categories is presented in Table 4.
Insights from the genome sequence
Genome sequencing of Planktotalea frisia SH6-1T resulted in 227 contigs with sizes between 0.51 kb and 181 kb. A detailed view on plasmid organization was not possible due to the number and length of contigs of the draft genome, but scanning the genome for typical plasmid repABC-type replication modules from Rhodobacterales  resulted in three modules, suggesting that this strain carries at least three extrachromosomal elements.
Phage-mediated horizontal gene transfer is known to drive genomic diversity of bacteria and prophage-like structures are common in marine bacteria . The genome of strain SH6-1T carries a complete gene transfer agent cluster (PFRI_24010–24170) organized similar to the first genetically characterized GTA agent of Rhodobacter capsulatus RcGTA  containing 14 of the 15 genes but lacking the orfg1 gene. RcGTA-like genes are present in all taxonomic orders of Alphaproteobacteria and within the Roseobacter group, except in most strains of the Pelagic Roseobacter Cluster, i.e. Planktomarina temperata , Planktomicrobium forsetii, Rhodobacterales bacterium HTCC2255 and HTCC2083 [3, 4, 9]. Only strain HTCC2150 of the PRC members encodes the GTA-like gene cluster .
Genes encoding type IV secretion systems (T4SSs), facilitating the transfer of proteins and nucleoprotein complexes by the formation of a pilus, were found in half of the analyzed genomes of marine representatives of the Roseobacter group [4, 8, 31]. Vir proteins are essential components for conjugation and hypothesized to play a role in the cell-cell contact between roseobacters and phytoplankton cells . The T4SS seems to be a unique pattern of marine organisms within the Roseobacter group, some Erythrobacteraceae and Caulobacteraceae . The genome of strain SH6-1T also encodes the complete T4SS for translocating DNA or proteins into other cells. It includes the virB operon (virB1 to − 11, excluding virB7; PFRI_11620–11730) mediating the transmembrane channel formation and the virD2 and virD4 relaxase and coupling proteins (PFRI_35220, PFRI_35230) analogous to the archetypal Agrobacterium tumefaciens VirB/D4 system . The presence of the Vir gene cluster in the genome of P. frisia indicates that this strain is able to transfer DNA and proteins into prokaryotic and/or eukaryotic cells.
Flagellar synthesis as well as motility seem to be of importance for surface attachment and biofilm formation in many Proteobacteria [34,35,36]. The genome of P. frisia SH6-1T exhibits some genes for flagellar synthesis but covering only 8 of 30 analyzed COG flagellar families. Analysis of the corresponding genes revealed that the flagellar loci are located at the terminus of the single contigs as it is also the case for Roseobacter sp. strain MED193 with only 11 of 30 genes grouping into COG flagellar families . Hence, a precise statement about the existence of a complete set and therefore a flagellum for strain SH6-1T is not possible but should not be excluded due to the detection of slight wobbling under laboratory conditions . The genome of strain P. frisia reveals, however, no genes encoding proteins associated to chemotaxis and the ability to move towards certain chemicals in the environment.
Roseobacters are well known to be involved in the transformation of dimethylsulfoniopropionate, a metabolite produced primarily by marine phytoplankton, either by demethylation or cleavage [4, 8, 37]. Strain SH6-1T harbors genes for both, the cleavage and the demethylation pathway, indicating its ability to utilize DMSP. Two genes encoding for the dimethylsulfoniopropionate demethylase converting DMSP into methylmercaptopropionate [38, 39] are present but genes encoding the subsequent degradation of MMPA to acetaldehyde are absent from the draft genome sequence. Genes encoding for the alternative DMSP cleavage pathway are present in P. frisia , DddP (PFRI_00730), DddQ (PFRI_14360) and DddW (PFRI_38540) producing dimethylsulfide and acrylate, which is in contrast to previous studies where no DMS formation for P. frisia was detected .
Carbon monoxide can be an additional potential electron donor, which is formed by photolysis of dissolved organic matter. Only Roseobacter strains containing both the definitive form I and putative form II of the CO dehydrogenases large subunit (coxL) are capable of oxidizing CO under laboratory conditions . Planktotalea frisia exhibits both gene structures the form I (coxMSL; PFRI_33480–33500) as well as form II (coxSLM; PFRI_01330–01350), but form I is lacking the downstream genes coxDEF detected in other genomes of the marine Roseobacter group . Hence, it needs to be proved if this strain is able to use CO as an additional electron donor.
Inorganic sulfur compounds play an important role for mixotrophic growth in the marine environment with thiosulfate as common compound in seawater. The Roseobacter group makes use of the oxidation of thiosulfate to sulfate using the periplasmic Sox multienzyme complex like Ruegeria pomeroyi . The genome of P. frisia SH6-1T encodes proteins associated to a set of sox genes (soxRSVWXYZABCDEF; PFRI_19680, PFRI_14240, PFRI_37660–37740) suggesting that reduced sulfur compounds can be a complementary energy source.
The genome of strain SH6-1T harbors genes for the high affinity phosphate transport system (pstSCAB; PFRI_11530–11560) and also for the transport (phnCDE; PFRI_11490–11510) and cleavage (phnGHIJKLN; PFRI_11290–11350) of phosphonate, a source of phosphorous (P) important when inorganic P becomes limiting .
Quite a few marine bacteria are capable of using light as an additional energy source. Proteorhodopsins are widely distributed in major bacterial groups like Flavobacteriia , Alphaproteobacteria and Gammaproteobacteria  and aerobic anoxygenic phototrophs are widely distributed within the Roseobacter group [2, 44] and also for P. frisia genes encoding subunits of the photosynthetic reactions center complex (pufML) were detected via specific PCR . Genes for a functional photosynthetic gene cluster (PFRI_28770–28970, PFRI_19280–19350, PFRI_19150–19250) were found in the genome of SH6-1T. They include bch and crt genes coding for the bacteriochlorophyll and carotenoid biosynthetic pathways, puf genes coding for the subunits of the light harvesting complex and the reaction center complex, hem genes and also genes for sensor proteins. Due to the structure of the puf-operon and presence of the additional pufX gene, only reported for the anaerobic Rhodobacter lineage so far, P. frisia can be assigned to the phylogroup E according to Yutin et al.  occurring only in coastal oceans. In addition, two genes encoding blue light sensors using FAD (BLUF; PFRI_28190, PFRI_41660) are also present in the genome of strain SH6-1T indicating possible blue light-dependent signal transduction.
To analyze the lifestyle of P. frisia the genome was also screened for genes associated with quorum sensing (QS). QS systems mediated by N-acyl-L-homoserine lactones (AHLs) provide significant benefits to the group and influence bacterial social traits such as virulence, motility and biofilm formation in many Proteobacteria including the Roseobacter group [46,47,48,49]. Genome analysis revealed the presence of genes encoding an N-acyl-L-homoserine lactone synthetase (luxI homolog; PFRI_23420) and a response regulator (luxR homolog; PFRI_23430) indicating that P. frisia can perform QS.
In addition to biogeochemically important features reported previously from other sequenced strains of the Roseobacter group e.g. [3, 41, 50, 51], genome analysis of P. frisia SH6-1T, which is closely related to a member of the Pelagic Roseobacter Cluster , HTCC2083, revealed the presence of at least three extrachromosomal elements and genes associated with quorum sensing and type IV secretion systems.
Correspondingly, we assume that this strain can switch between free-living and an algal host associated lifestyle.
Acyl homoserine lactones
Integrated microbial genomes
Type IV secretion system
Brinkhoff T, Giebel HA, Simon M. Diversity, ecology, and genomics of the Roseobacter clade: a short overview. Arch Microbiol. 2008;189:531–9.
Buchan A, González JM, Moran MA. Overview of the marine Roseobacter lineage. Appl Environ Microbiol. 2005;71:5665–77.
Voget S, Wemheuer B, Brinkhoff T, Vollmers J, Dietrich S, Giebel HA, et al. Adaptation of an abundant Roseobacter RCA organism to pelagic systems revealed by genomic and transcriptomic analyses. ISME J. 2014;9:1–14.
Newton RJ, Griffin LE, Bowles KM, Meile C, Gifford S, Givens CE, et al. Genome characteristics of a generalist marine bacterial lineage. ISME J. 2010;4:784–98.
Bruhn JB, Gram L, Belas R. Production of antibacterial compounds and biofilm formation by Roseobacter species are influenced by culture conditions. Appl Environ Microbiol. 2007;73:442–50.
Wagner-Döbler I, Rheims H, Felske A, El-Ghezal A, Flade-Schröder D, Laatsch H, et al. Oceanibulbus indolifex gen. Nov., sp. nov., a North Sea alphaproteobacterium that produces bioactive metabolites. Int J Syst Evol Microbiol. 2004;54:1177–84.
Ziesche L, Bruns H, Dogs M, Wolter L, Mann F, Wagner-Döbler I, et al. Homoserine lactones, methyl oligohydroxybutyrates, and other extracellular metabolites of macroalgae-associated bacteria of the Roseobacter clade: identification and functions. Chembiochem. 2015;16:2094–107.
Moran MA, Belas R, Schell MA, González JM, Sun F, Sun S, et al. Ecological genomics of marine roseobacters. Appl Environ Microbiol. 2007;73:4559–69.
Billerbeck S, Wemheuer B, Voget S, Poehlein A, Giebel HA, Brinkhoff T, et al. Biogeography and environmental genomics of the Roseobacter-affiliated pelagic CHAB-I-5 lineage. Nat Microbiol. 2016; https://doi.org/10.1038/nmicrobiol.2016.63.
Kang I, Vergin KL, Oh HM, Choi A, Giovannoni SJ, Cho JC. Genome sequence of strain HTCC2083, a novel member of the marine clade Roseobacter. J Bacteriol. 2011;193:319–20.
Hahnke S, Tindall BJ, Schumann P, Sperling M, Brinkhoff T, Simon M. Planktotalea frisia gen. Nov., sp. nov., isolated from the southern North Sea. Int J Syst Evol Microbiol. 2012;62:1619–24.
Hahnke S, Sperling M, Langer T, Wichels A, Gerdts G, Beardsley C, et al. Distinct seasonal growth patterns of the bacterium Planktotalea frisia in the North Sea and specific interaction with phytoplankton algae. FEMS Microbiol Ecol. 2013;86:185–99.
Hahnke S, Brock NL, Zell C, Simon M, Dickschat JS, Brinkhoff T. Physiological diversity of Roseobacter clade bacteria co-occurring during a phytoplankton bloom in the North Sea. Syst Appl Microbiol. 2013;36:39–48.
Altschul SF, Gish W, Miller W, Myers EW, Lipman DJ. Basic local alignment search tool. J Mol Biol. 1990;215:403–10.
Ludwig W, Strunk O, Westram R, Richter L, Meier H, Yadhukumar A, et al. ARB: a software environment for sequence data. Nucleic Acids Res. 2004;32:1363–71.
Pagani I, Liolios K, Jansson J, Chen IMA, Smirnova T, Nosrat B, et al. The genomes OnLine database (GOLD) v.4: status of genomic and metagenomic projects and their associated metadata. Nucleic Acids Res. 2012;40:571–9.
Markowitz VM, Chen IMA, Palaniappan K, Chu K, Szeto E, Grechkin Y, et al. IMG: the integrated microbial genomes database and comparative analysis system. Nucleic Acids Res. 2012;40:115–22.
Gemeinholzer B, Dröge G, Zetzsche H, Haszprunar G, Klenk HP, Güntsch A, et al. The DNA Bank network: the start from a German initiative. Biopreserv Biobank. 2011;9:51–5.
Bolger AM, Lohse M, Usadel B. Trimmomatic: a flexible trimmer for Illumina sequence data. Bioinformatics. 2014;30:2114–20.
Bankevich A, Nurk S, Antipov D, Gurevich AA, Dvorkin M, Kulikov AS, et al. SPAdes: a new genome assembly algorithm and its applications to single-cell sequencing. J Comput Biol. 2012;19:455–77.
Hyatt D, Chen GL, LoCascio PF, Land ML, Larimer FW, Hauser LJ. Prodigal: prokaryotic gene recognition and translation initiation site identification. BMC Bioinformatics. 2010;11:119.
Lowe TM, Eddy SR. TRNAscan-SE: a program for improved detection of transfer RNA genes in genomic sequence. Nucleic Acids Res. 1996;25:955–64.
Lagesen K, Hallin P, Rødland EA, Stærfeldt HH, Rognes T, Ussery DW. RNAmmer: consistent and rapid annotation of ribosomal RNA genes. Nucleic Acids Res. 2007;35:3100–8.
Nawrocki EP, Burge SW, Bateman A, Daub J, Eberhardt RY, Eddy SR, et al. Rfam 12.0: updates to the RNA families database. Nucleic Acids Res. 2015;43:D130–7.
Krogh A, Larsson B, von Heijne G, Sonnhammer ELL. Predicting transmembrane protein topology with a hidden Markov model: application to complete genomes. J Mol Biol. 2001;305:567–80.
Bendtsen JD, Nielsen H, von Heijne G, Brunak S. Improved prediction of signal peptides: SignalP 3.0. J Mol Biol. 2004;340:783–95.
Markowitz VM, Chen IMA, Chu K, Szeto E, Palaniappan K, Pillay M, et al. IMG/M 4 version of the integrated metagenome comparative analysis system. Nucleic Acids Res. 2014;42:568–73.
Petersen J, Frank O, Göker M, Pradella S. Extrachromosomal, extraordinary and essential - the plasmids of the Roseobacter clade. Appl Microbiol Biotechnol. 2013;97:2805–15.
Paul JH. Prophages in marine bacteria: dangerous molecular time bombs or the key to survival in the seas? ISME J. 2008;2:579–89.
Lang AS, Beatty JT. The gene transfer agent of Rhodobacter capsulatus and “constitutive transduction” in prokaryotes. Arch Microbiol. 2001;175:241–9.
Slightom RN, Buchan A. Surface colonization by marine roseobacters: integrating genotype and phenotype. Appl Environ Microbiol. 2009;75:6027–37.
Persson OP, Pinhassi J, Riemann L, Marklund BI, Rhen M, Normark S, et al. High abundance of virulence gene homologues in marine bacteria. Environ Microbiol. 2009;11:1348–57.
Christie PJ, Atmakuri K, Krishnamoorthy V, Jakubowski S, Cascales E. Biogenesis, architecture, and function of bacterial type IV secretion systems. Annu Rev Microbiol. 2005;59:451–85.
Fujishige NA, Kapadia NN, De Hoff PL, Hirsch AM. Investigations of Rhizobium biofilm formation. FEMS Microbiol Ecol. 2006;56:195–206.
Merritt PM, Danhorn T, Fuqua C. Motility and chemotaxis in Agrobacterium tumefaciens surface attachment and biofilm formation. J Bacteriol. 2007;189:8005–14.
O'Toole G, Kaplan HB, Kolter R. Biofilm formation as microbial development. Annu Rev Microbiol. 2000;54:49–79.
Lenk S, Moraru C, Hahnke S, Arnds J, Richter M, Kube M, et al. Roseobacter clade bacteria are abundant in coastal sediments and encode a novel combination of sulfur oxidation genes. ISME J. 2012;6:2178–87.
Curson ARJ, Todd JD, Sullivan MJ, Johnston AWB. Catabolism of dimethylsulphoniopropionate: microorganisms, enzymes and genes. Nat Rev Microbiol. 2011;9:849–59.
Reisch CR, Moran MA, Whitman WB. Bacterial catabolism of dimethylsulfoniopropionate (DMSP). Front Microbiol. 2011;2:1–12.
Cunliffe M. Correlating carbon monoxide oxidation with cox genes in the abundant marine Roseobacter clade. ISME J. 2011;5:685–91.
Moran MA, Buchan A, González JM, Heidelberg JF, Whitman WB, Kiene RP, et al. Genome sequence of Silicibacter pomeroyi reveals adaptations to the marine environment. Nature. 2004;432:910–3.
Kolowith LC, Ingall ED, Benner R. Composition and cycling of marine organic phosphorus. Limnol Oceanogr. 2001;46:309–20.
Fuhrman JA, Schwalbach MS, Stingl U. Proteorhodopsins: an array of physiological roles? Nat Rev Microbiol. 2008;6:488–94.
Wagner-Döbler I, Biebl H. Environmental biology of the marine Roseobacter lineage. Annu Rev Microbiol. 2006;60:255–80.
Yutin N, Suzuki MT, Teeling H, Weber M, Venter JC, Rusch DB, et al. Assessing diversity and biogeography of aerobic anoxygenic phototrophic bacteria in surface waters of the Atlantic and Pacific oceans using the Global Ocean sampling expedition metagenomes. Environ Microbiol. 2007;9:1464–75.
Fuqua C, Winans SC, Greenberg EP. CENSUS AND CONSENSUS IN BACTERIAL ECOSYSTEMS: the LuxR-LuxI family of quorum-sensing transcriptional regulators. Annu Rev Microbiol. 1996;50:727–51.
Parsek MR, Greenberg EP. Sociomicrobiology: the connections between quorum sensing and biofilms. Trends in Microbiol. 2005;13:27–33.
Ng WL, Bassler BL. Bacterial quorum-sensing network architectures. Annu Rev Genet. 2009;43:197–222.
Patzelt D, Wang H, Buchholz I, Rohde M, Gröbe L, Pradella S, et al. You are what you talk: quorum sensing induces individual morphologies and cell division modes in Dinoroseobacter shibae. ISME J. 2013;7:2274–86.
Wagner-Döbler I, Ballhausen B, Berger M, Brinkhoff T, Buchholz I, Bunk B, et al. The complete genome sequence of the algal symbiont Dinoroseobacter shibae: a hitchhiker’s guide to life in the sea. ISME J. 2010;4:61–77.
Riedel T, Spring S, Fiebig A, Scheuner C, Petersen J, Göker M. Genome sequence of the Roseovarius mucosus type strain ( DSM 17069T), a bacteriochlorophyll a -containing representative of the marine Roseobacter group isolated from the dinoflagellate Alexandrium ostenfeldii. Stand Genomic Sci. 2015;10:17.
Kalhoefer D, Thole S, Voget S, Lehmann R, Liesegang H, Wollher A, et al. Comparative genome analysis and genome-guided physiological analysis of Roseobacter litoralis. BMC Genomics. 2011;12:324.
Field D, Garrity G, Gray T, Morrison N, Selengut J, Sterk P, et al. The minimum information about a genome sequences (MIGS) specification. Nat Biotechnol. 2008;26:541–7.
Field D, Amaral-Zettler L, Cochrane G, Cole JR, Dawyndt P, Garrity GM, et al. Clarifying concepts and terms in biodiversity informatics. PLoS Biol. 2011;9:e1001088.
Woese CR, Kandler O, Wheelis ML. Towards a natural system of organisms. Proposal for the domains Archaea, Bacteria and Eucarya. Proc Natl Acad Sci U S A. 1990;87:4576–9.
Garrity GM, Bell JA, Lilburn T, Phylum XIV. Proteobacteria phyl. Nov. In: Brenner DJ, Krieg NR, Staley JT, Garrity GM, editors. Bergey's manual of systematic bacteriology. Second edition, Vol. 2 (the Proteobacteria), part B (the Gammaproteobacteria). New York: Springer; 2005. p. 1.
Garrity GM, Bell JA, Lilburn T, Class I. Alphaproteobacteria class. Nov. In: Garrity GM, Brenner DJ, Krieg NR, Stanley JT, editors. Bergey's manual of systematic bacteriology. Second edition, Vol. 2, part C. New York: Springer; 2005. p. 1.
Validation List No. 107. List of new names and new combinations previously effectively, but not validly, published. Int J Syst Evol Microbiol. 2006;56:1–6.
Garrity GM, Bell JA, Lilburn T, Order III. Rhodobacterales Ord. Nov. In: Brenner DJ, Krieg NR, Stanley JT, editors. Bergey's manual of systematic bacteriology. Second edition, Vol. 2, part C. New York: Springer; 2005. p. 161.
Garrity GM, Bell JA, Lilburn T, Family I. Rhodobacteraceae fam. nov. In: Garrity GM, Brenner DJ, Krieg NR, Stanley JT, editors. Bergey's manual of systematic bacteriology. Second edition, Vol. 2, part C. New York: Springer; 2005. p. 161.
Ashburner M, Ball CA, Blake JA, Botstein D, Butler H, Cherry JM, et al. Gene ontology: tool for the unification of biology. Nat Genet. 2000;25:25–9.
The authors gratefully acknowledge the help of Sarah Hahnke with growing cells and providing pictures of P. frisia SH6-1T. We thank Frauke Dorothee Meyer and Kathleen Gollnow for technical support. Furthermore we thank Sara Billerbeck, Sven Breider and Helge-Ansgar Giebel for valuable discussions relating to genome analysis. The work was performed within the frame of the Collaborative Research Center Transregio-SFB 51, Roseobacter , supported by Deutsche Forschungsgemeinschaft.
The authors declare they have no competing interests.
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
About this article
- Marine bacterioplankton
- Roseobacter group
- Type IV secretion system
- Quorum sensing