title: A novel cyanobacterium exhibiting an elevated tolerance for iron.
abstract: Studies directed at cyanobacteria inhabiting iron-depositing hot springs may provide insights into the role of both ancient and contemporary cyanobacteria mediated iron transformations. Here we phylogenetically, morphologically and physiologically characterize a novel cyanobacterium isolated from an iron-depositing hot spring. Phylogenetic analyses indicate that the bacterium is a representative of a new genus, exhibiting a maximum 95.2% homology to database sequences. The isolate is a unicellular cyanobacterium with bladder-like cells typically packed as duplexes, or in extracellular polymeric substance covered clumps and small chains without the ability to produce baeocystes. No growth without added combined nitrogen occurred. While requiring relatively large amounts of iron for growth (>40microM), the isolate was shown to facilitate removal of iron from culture media. These results suggest that the isolate may be an important component of an iron-depositing microbial community. The name "Chroogloeocystis siderophila" for this cyanobacterium is proposed.
authors.affiliation: The Department of Microbiology, Montana State University, 109 Lewis Hall, Bozeman, MT 59717, USA. igor.i.brownl@jsc.nasa.gov
authors.forename: Igor I
authors.initials: II
authors.lastname: Brown
authors.forename: Daniel
authors.initials: D
authors.lastname: Mummey
authors.forename: Keith E
authors.initials: KE
authors.lastname: Cooksey
mesh_terms: D015373:Bacterial Typing Techniques; D000458:Cyanobacteria / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology; D004269:DNA, Bacterial / Q000032:analysis; D004275:DNA, Ribosomal / Q000032:analysis; D045482:Hot Springs / Q000382:microbiology*; D007501:Iron / Q000378:metabolism*; D008969:Molecular Sequence Data; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S; D007501:Iron