A unicellular cyanobacterium, designated KORDI 51-2, was isolated from surface seawater of Chuuk lagoon, Micronesia. The cells were wine-coloured rods and emitted red fluorescence under green excitation of an epifluorescence microscope. Thus, morphologically, the strain resembled species. However, based on 16S rRNA gene sequence similarities between strain KORDI 51-2 and related strains belonging to cyanobacteria, the novel strain was distantly related to members of the ‘’ cluster. However, sequence similarities between strain KORDI 51-2 and members of the ‘’ cluster were very low, ranging from 90.7 to 92.1 %, and phylogenetic analyses showed that the strain formed a distinct branch. Therefore, a polyphasic characterization including morphology, physiology and pigment composition was conducted to elucidate the taxonomic position of strain KORDI 51-2. The strain grew within a temperature range of 25–35 °C and a salinity range of 2–7 %. The optimal temperature and salinity were about 30 °C and 5 %, respectively. Strain KORDI 51-2 contained phycoerythrin, and the dominant carotenoid pigments were zeaxanthin, -carotene and echinenone. The DNA G+C content was 60.5 mol%. Based on phylogenetic analysis of the 16S rRNA gene sequence, and the physiological data and pigment compositions, strain KORDI 51-2 is considered to represent a new genus and novel species of cyanobacteria for which the name gen. nov., sp. nov. is proposed. The type strain is KORDI 51-2 (=KCTC 40015=UTEX L2944).


Article metrics loading...

Loading full text...

Full text loading...



  1. Altschul, S. F., Gish, W., Miller, W., Myers, E. W. & Lipman, D. J.(1990). Basic local alignment search tool. J Mol Biol 215, 403–410.[CrossRef] [Google Scholar]
  2. Castenholz, R. W.(2001). General characteristics of the cyanobacteria. In Bergey's Manual of Systematic Bacteriology, 2nd edn, vol. 1, pp. 474–487. Edited by D. R. Boone & R. W. Castenholz. New York: Springer.
  3. Felsenstein, J.(1981). Evolutionary trees from DNA sequences: a maximum likelihood approach. J Mol Evol 17, 368–376.[CrossRef] [Google Scholar]
  4. Fitch, W. M.(1971). Toward defining the course of evolution: minimum change for a specific tree topology. Syst Zool 20, 406–416.[CrossRef] [Google Scholar]
  5. Fuller, N. J., Marie, D., Partensky, F., Vaulot, D., Post, A. F. & Scanlan, D. J.(2003). Clade-specific 16S ribosomal DNA oligonucleotides reveal the predominance of a single marine Synechococcus clade throughout a stratified water column in the Red Sea. Appl Environ Microbiol 69, 2430–2443.[CrossRef] [Google Scholar]
  6. Garcia-Pichel, F., Nübel, U. & Muyzer, G.(1998). The phylogeny of unicellular, extremely halotolerant cyanobacteria. Arch Microbiol 169, 469–482.[CrossRef] [Google Scholar]
  7. Guillard, R. R. L.(1975). Culture of phytoplankton for feeding marine invertebrates. In Culture of Marine Invertebrate Animals, pp. 26–60. Edited by W. L. Smith & M. H. Chanley. New York: Plenum Press.
  8. Herdman, M., Castenholz, R. W., Iteman, I., Waterbury, J. B. & Rippka, R.(2001). Subsection I. In Bergey's Manual of Systematic Bacteriology, 2nd edn, vol. 1, pp. 493–514. Edited by D. R. Boone & R. W. Castenholz. New York: Springer.
  9. Jeon, Y.-S., Chung, H., Park, S., Hur, I., Lee, J.-H. & Chun, J.(2005). jPHYDIT: a JAVA-based integrated environment for molecular phylogeny of ribosomal RNA sequences. Bioinformatics 21, 3171–3173.[CrossRef] [Google Scholar]
  10. Jukes, T. H. & Cantor, C. R.(1969). Evolution of protein molecules. In Mammalian Protein Metabolism, pp. 21–132. Edited by H. N. Munro. New York: Academic Press.
  11. Koblížek, M., Komenda, J. & Masojídek, J.(2000). Cell aggregation of the cyanobacterium Synechococcus elongatus: Role of the electron transport chain. J Phycol 36, 662–668.[CrossRef] [Google Scholar]
  12. Komárek, J. & Anagnostidis, K.(1995). Nomenclatural novelties in chroococcalean cyanoprokaryotes. Preslia Praha 67, 15–23. [Google Scholar]
  13. Kumar, S., Tamura, K. & Nei, M.(2004).mega3: Integrated software for Molecular Evolutionary Genetics Analysis and sequence alignment. Brief Bioinform 5, 150–163.[CrossRef] [Google Scholar]
  14. Lapage, S. P., Sneath, P. H. A., Lessel, E. F., Skerman, V. B. D., Seeliger, H. P. R. & Clark, W. A. (editors)(1992).International Code of Nomenclature of Bacteria (1990 Revision). Bacteriological Code. Washington, DC: American Society for Microbiology.
  15. Lyman, J. & Fleming, R. H.(1940). Composition of sea water. J Mar Res 3, 134–146. [Google Scholar]
  16. Marmur, J.(1961). A procedure for the isolation of deoxyribonucleic acid from microorganisms. J Mol Biol 3, 208–218.[CrossRef] [Google Scholar]
  17. McBain, A. J., Bartolo, R. G., Catrenich, C. E., Charbonneau, D., Ledder, R. G., Rickard, A. H., Symmons, S. A. & Gilbert, P.(2003). Microbial characterization of biofilms in domestic drains and the establishment of stable biofilm microcosms. Appl Environ Microbiol 69, 177–185.[CrossRef] [Google Scholar]
  18. Mesbah, M., Premachandran, U. & Whitman, W. B.(1989). Precise measurement of the G+C content of deoxyribonucleic acid by high performance liquid chromatography. Int J Syst Bacteriol 39, 159–167.[CrossRef] [Google Scholar]
  19. Oren, A.(2004). A proposal for further integration of the cyanobacteria under the Bacteriological Code. Int J Syst Evol Microbiol 54, 1895–1902.[CrossRef] [Google Scholar]
  20. Posada, D. & Crandall, K. A.(1998).modeltest: testing the model of DNA substitution. Bioinformatics 14, 817–818.[CrossRef] [Google Scholar]
  21. Saitou, N. & Nei, M.(1987). The neighbor-joining method: a new method for reconstructing phylogenetic trees. Mol Biol Evol 4, 406–425. [Google Scholar]
  22. Swofford, D. L.(1998).paup*: Phylogenetic analysis using parsimony (and other methods), version 4. Sunderland, MA: Sinauer Associates.
  23. Whitton, B. A. & Potts, M. (editors)(2000).The Ecology of Cyanobacteria: Their Diversity in Time and Space. Dordrecht: Kluwer Academic.
  24. Zapata, M., Rodríguez, F. & Garrido, J. L.(2000). Separation of chlorophylls and carotenoids from marine phytoplankton: a new HPLC method using a reversed phase C8 column and pyridine-containing mobile phases. Mar Ecol Prog Ser 195, 29–45.[CrossRef] [Google Scholar]

Data & Media loading...


Micrographs of cells of strain KORDI 51-2 in exponential and stationary growth phases. [PDF](383 KB)


Graphs showing the growth rates of strain KORDI 51-2 at various temperatures and salinities. [PDF](22 KB)


Most cited this month Most Cited RSS feed

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error