RESULTS:
1 - 5 of 5 for ""iron reduction""
Alkaliphilus namsaraevii sp. nov., an alkaliphilic iron- and sulfur-reducing bacterium isolated from a steppe soda lake
A novel alkaliphilic spore-forming bacterium was isolated from the benthic sediments of the highly mineralized steppe Lake Khilganta (Transbaikal Region Russia). Cells of the strain designated Х-07-2T were straight to slightly curved rods Gram-stain-positive and motile. Strain Х-07-2T grew in the pH range from 7.0 to 10.7 (optimum pH 9.6–10.3). Growth was observed at 25–47 °C (optimum 30 °C) and at an NaCl concentration from 5 to 150 g l−1 with an optimum at 40 g l−1. Strain Х-07-2T was a chemo-organoheterotroph able to reduce amorphous ferric hydroxide Fe(III) citrate and elemental sulfur in the presence of yeast extract as the electron donor. It used tryptone peptone and trypticase with Fe(III) citrate as the electron acceptor. The predominant fatty acids in cell walls were C16:1ω8 iso-C15:0 C14 : 0 3-OH and C16 : 0. The DNA G+C content was 32.6 mol%. 16S rRNA gene sequence analysis revealed that strain Х-07-2T was related most closely to members of the genus Alkaliphilus within the family Clostridiaceae . The closest relative was Alkaliphilus peptidifermentans Z-7036T (96.4 % similarity). On the basis of the genotypic chemotaxonomic and phenotypic data strain Х-07-2T represents a novel species in the genus Alkaliphilus for which the name Alkaliphilus namsaraevii sp. nov. is proposed. The type strain is Х-07-2T (=VKM В-2746Т=DSM 26418Т).
Isachenkonia alkalipeptolytica gen. nov. sp. nov., a new anaerobic, alkaliphilic proteolytic bacterium capable of reducing Fe(III) and sulfur
An obligately alkaliphilic anaerobic proteolytic bacterium was isolated from a sample of Tanatar III soda lake sediment (Altai region Russia) and designated as strain Z-1701T. Cells of strain Z-1701T were short straight motile Gram-stain-positive rods. Growth of Z-1701T obligately depended on the presence of sodium carbonate. Strain Z-1701T could utilize various peptides mixtures such as beef and yeast extracts peptone soytone trypticase and tryptone as well as such proteins as albumin gelatin and sodium caseinate. It was able to grow oligotrophically with 0.02 g l−1 yeast extract as the sole energy and carbon source. Carbohydrates did not support the growth of strain Z-1701T. The main products released during the growth of strain Z-1701T on tryptone were formate acetate and ammonium. Strain Z-1701T was able to reduce ferrihydrite Fe(III)-EDTA anthraquinone-26-disulfonate and elemental sulfur using proteinaceous substrates as electron donors. In all cases the presence of the electron acceptor in the medium stimulated growth. The main cellular fatty acids were iso-C15 : 0 iso-C15 : 0 aldehyde iso-C15 : 1 ω6 C16 : 0 iso-C17 : 0 aldehyde C16 : 0 aldehyde and C14 : 0. The DNA G+C content of the isolate was 43.9 mol%. Phylogenetic analysis based on the concatenated alignment of 120 protein-marker sequences revealed that strain Z-1701T falls into a cluster with the genus Tindallia family Clostridiaceae . 16S rRNA gene sequence identity between strain Z-1701T and Tindallia species were 88.3–89.75 %. On the basis of its phenotypic characteristics and phylogenetic position the novel isolate is considered to be a representative of a novel genus and species for which the name Isachenkonia alkalipeptolytica gen. nov. sp. nov. is proposed with Z-1701T (=JCM 32929Т=DSM 109060Т=VKM B-3261Т) as its type strain.
Acidiferrimicrobium australe gen. nov., sp. nov., an acidophilic and obligately heterotrophic, member of the Actinobacteria that catalyses dissimilatory oxido-reduction of iron isolated from metal-rich acidic water in Chile
A novel acidophilic member of the phylum Actinobacteria was isolated from an acidic metal-contaminated stream draining from an abandoned underground coal mine (Trongol mine) situated close to Curanilahue Biobío Region Chile. The isolate (USS-CCA1T) was demonstrated to be a heterotroph that catalysed under aerobic conditions the oxidation of ferrous iron and the reduction of ferric iron under anaerobic conditions but not the oxidation of sulfur nor hydrogen. USS-CCA1T is a Gram-positive motile short rod-shaped mesophilic bacterium with a temperature growth optimum at 30 °C (range 20–39 °C). It was categorized as an extreme acidophile growing between 1.7 and 4.5 and optimally at pH 3.0. The G+C content of the chromosomal DNA of the isolate was 74.1 mol% which is highly related to Aciditerrimonas ferrireducens IC-180T (the most closely related genus; 94.4 % 16S rRNA gene identity) and higher than other acidophilic actinobacteria. The isolate (USS-CCA1T) was shown to form a distinct 16S rRNA clade from characterized acidophilic actinobacteria well separated from the genera Acidimicrobium Ferrimicrobium Ferrithrix ‘Acidithrix’ and Aciditerrimonas . Genomic indexes (ANIb DDH AAI POCP) derived from the USS-CCA1T draft genome sequence (deposited at DDBJ/ENA/GenBank under the accession WJHE00000000) support assignment of the isolate to a new species and a new genus within the Acidimicrobiaceae family. Isolate USS-CCA1T is the designated type strain of the novel species Acidiferrimicrobium australe (=DSM 106828T=RGM 2506T).
Fusibacter ferrireducens sp. nov., an anaerobic, Fe(Ⅲ)- and sulphur-reducing bacterium isolated from mangrove sediment
An anaerobic alkaliphilic halotolerant Gram-stain-positive and rod-shaped bacterium designated Q10-2T was isolated from mangrove sediment sampled at the Jiulong river estuary PR China. The cells of strain Q10-2T were motile and 0.5×2–4 µm in size. Strain Q10-2T grew at 8–45 °C (optimum 32 °C) at pH 7.0–10.5 (optimum pH 8.5) and in the presence of 0–6 % (w/v) NaCl (optimum 3 %). It could use complex organic compounds and carbohydrates including d-fructose d-galactose d-glucose d-mannitol d-xylose trehalose lactose maltose sucrose and starch as carbon sources and electron donors. It could reduce sulphate thiosulphate and elemental sulphur to sulphide but not sulphite. Fe (Ⅲ) citrate ferrihydrite haematite and goethite in the presence of glucose as the electron donor were also reduced. Acetate butyrate ethanol CO2 and H2 were end products of glucose fermentation. The predominant cellular fatty acids were composed of C14 : 0 C16 : 0 and summed features containing C16 : 1 ω7c and/or iso-C15 : 0 2-OH and iso-C17 : 1 and/or anteiso-C17 : 1 B. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the novel strain was most closely related to Fusibacter paucivorans DSM 12116T (95.5 % sequence similarity). The genome size of strain Q10-2T was 5.0 Mb with a G+C content of 37.4 mol%. The average nucleotide identity and digital DNA–DNA hybridization values between strain Q10-2T and F. paucivorans DSM 12116T were 69.1 and 21.8 % respectively. The combined genotypic and phenotypic data showed that strain Q10-2T represents a novel species of the genus Fusibacter for which the name Fusibacter ferrireducens sp. nov. is proposed. The type strain is Q10-2T (=MCCC 1A16257T=KCTC 15906T).
Rhodoferax lithotrophicus sp. nov., a neutrophilic iron-oxidizing and -reducing bacterium isolated from iron-rich freshwater sediments
A neutrophilic iron-oxidizing and -reducing bacterium strain MIZ03T was previously isolated from a wetland in Ibaraki Japan. Here we report the detailed characteristics of this strain. It was motile with a single polar flagellum and Gram-stain-negative. It could grow not only chemolithoautotrophically but also chemoorganotrophically by aerobic respiration and fermentation. Major cellular fatty acids were C16 : 1 ω7c/C16 : 1 ω6c and C16 : 0. Phylogenetic analyses indicated that strain MIZ03T belonged to the genus Rhodoferax. This strain was closely related to Rhodoferax ferrireducens with 98.5 % of 16S rRNA gene sequence similarity. Based on its phenotypic and genomic based characteristics we conclude that strain MIZ03T represents a new species in the genus Rhodoferax. We propose the name Rhodoferax lithotrophicus sp. nov. to accommodate this strain. The type strain is MIZ03T (=JCM 34246T=DSM 113266T). We also propose the name Rhodoferax koreensis sp. nov. of which the type strain is DCY110T (=KCTC 52288T=JCM 31441T) for the effectively but not yet validly published name ‘Rhodoferax koreense’.