title: Characterization of unusual alkaliphilic gram-positive bacteria isolated from degraded brown alga thalluses.
abstract: Two orange-pigmented Gram-positive, aerobic bacteria were isolated from enrichment culture during degradation of brown alga Fucus evanescens thalluses. In this work, atomic force microscopy (AFM) has been used to study the cell morphology. The non-contact mode imaging revealed unusual irregular coccoid shape of cells, possessing a single flagellum. Bacteria produced carotenoid pigments, were chemo-organotrophic, alkaliphilic and halo-tolerant growing well on nutrient media containing up to 15% NaCl. Growth temperature ranged from 5 to 45 degrees C. The DNA base compositions were 48 mol% G + C and the level of DNA similarity of two strains was conspecific (98%). A comparative phylogenetic analysis of 16S rRNA gene sequences revealed that the strain KMM 3738 tightly clustered with recently described Planococcus maritimus (99.9% 16S rRNA gene sequence similarity). DNA-DNA hybridisation experiments revealed that DNA from the KMM 3738 showed 12-15% and 16-35% of genetic relatedness with the DNA of type strains of the genera Planomicrobium and Planococcus, respectively, and 87% with DNA from Planococcus maritimus, indicating that new isolates belong to the later species.
authors.affiliation: Swinburne University of Technology, PO Box 218, Hawthorn, Vic 3122, Australia.
authors.forename: E P
authors.initials: EP
authors.lastname: Ivanova
authors.forename: J P
authors.initials: JP
authors.lastname: Wright
authors.forename: A M
authors.initials: AM
authors.lastname: Lysenko
authors.forename: N V
authors.initials: NV
authors.lastname: Zhukova
authors.forename: Y V
authors.initials: YV
authors.lastname: Alexeeva
authors.forename: V
authors.initials: V
authors.lastname: Buljan
authors.forename: N I
authors.initials: NI
authors.lastname: Kalinovskaya
authors.forename: D V
authors.initials: DV
authors.lastname: Nicolau
authors.forename: R
authors.initials: R
authors.lastname: Christen
authors.forename: V V
authors.initials: VV
authors.lastname: Mikhailov
mesh_terms: D015373:Bacterial Typing Techniques; D004269:DNA, Bacterial / Q000032:analysis; D044645:Fucus / Q000382:microbiology*; D006094:Gram-Positive Bacteria / Q000235:genetics / Q000302:isolation & purification* / Q000648:ultrastructure; D046529:Microscopy, Electron, Transmission; D010802:Phylogeny; D012329:RNA, Bacterial / Q000032:analysis; D012336:RNA, Ribosomal, 16S / Q000032:analysis
chemical_list: D004269:DNA, Bacterial; D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S