Search

Two thermophilic spore-forming strains, with optimum growth temperature at 70°C, were isolated from compost of the "Experimental System of Composting" (Teora, Avellino, Italy). A phylogenetic analysis based on 16S rRNA gene sequences showed that these organisms represented a new species of the genus Geobacillus. Based on polyphasic taxonomic data the strains represented a novel species for which the name Geobacillus galactosidasius sp. nov. is proposed. The type strain is CF1B(T) (=ATCC BAA-1450(T)=DSM 18751(T))., (Copyright © 2011 Elsevier GmbH. All rights reserved.)

The taxomony of strain CRSS (DSM 15686(T)=ATCC BAA-848(T)) isolated from Cape Russell in Antarctica (Ross Sea, 74 52.35 S 163 53.03 E) was investigated in a polyphasic approach. The morphological, physiological and genetic characteristics were compared with that of related species of the genus Halomonas. The isolate grew optimally at pH 9.0, 10% NaCl at 30 degrees C. The cells were Gram-negative aerobic rods able to produce exopolysaccharide. They accumulated glycine-betaine, as a major osmolyte, with minor components ectoine and glutamate. The strain CRSS biosynthetised alpha-glucosidase. The polar lipid profile consisted of phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol as major components. Ubiquinone with nine repetitive unities (Q9) was the only quinone found and the fatty acid composition was dominated by C18:1 (53%). The G+C content of DNA was 55.0mol% and its phylogenetic position was established by 16S rRNA gene sequencing as a member of the genus Halomonas. For physiological, chemotaxonomic and genetic features (DNA-DNA hybridisation) it is proposed to classify the isolate as a new species for which we propose the name Halomonas alkaliantarctica sp. nov.

A new thermophilic spore-forming strain MR3CT was isolated from geothermal soil located on Mount Rittmann in Antarctica. Strain MR3CT was Gram-positive, rod-shaped, occurring in pairs or filamentous. Growth was observed between 45 and 65 degrees C (optimum 61 degrees C) and at pH 5.0-6.5 (optimum pH 5.6). It was capable of utilizing galactose, trehalose, maltose and sucrose. The microorganism produced an exopolysaccharide and synthesized an extracellular constitutive amylolytic activity. The G + C content of DNA was 43.5 mol%. On the basis of 16S rRNA gene sequence similarity, strain MR3CT was shown to be related most closely to Anoxybacillus species. Chemotaxonomic data (major isoprenoid quinone-menaquinone-7; major fatty acid-iso-C15:0 and iso-C17:0) supported the affiliation of strain MR3C1T to the genus Anoxybacillus. The results of DNA-DNA hybridization, physiological and biochemical tests allowed genotypic and phenotypic differentiation of strain MR3CT from the validly published Anoxybacillus species. MR3CT therefore represents a new species, for which the name Anoxybacillus amylolyticus sp. nov., is proposed, with the type strain MR3CT (= ATCC BAA-872T = DSM 15939T = CIP 108338T).

A Gram-negative, aerobic, motile and rod-shaped haloalkaliphilic bacterial strain 5AGT (DSM 15293 and ATCC BAA-966) was isolated from water with algal mat of a mineral pool in Malvizza site (Campania-Italy) and was subjected to a polyphasic study. The isolate grew at temperature of 10.0-43.0 degrees C with an optimum at 37.0 degrees C. Strain 5AGT grew optimally in the presence of 10% NaCl and grew also in the absence of salt. The isolate grew in the pH range 7.0-10.0 with an optimum at pH 9.0. It accumulated glycine-betaine, ectoine, and glutamate, as osmoprotectants. Strain 5AGT was also characterized chemotaxonomically by having ubiquinone-8 (Q8) as the predominant isoprenoid quinone, phosphoethanolamine (PEA), phosphatidylglycerol (PG) and diphosphatidylglycerol (DPG), as major polar lipids and aiC16:0 and C18:1cis as the major fatty acids. The DNA G+C content was 63.7mol%. Phylogenetic analyses based on 16S rRNA gene sequence showed that the isolate belonged to the genus Halomonas. The DNA-DNA hybridization of the type strain 5AGT with the most related Halomonas campisalis showed a re-association value of 35.0%. On the basis of phenotypic properties and phylogeny, strain 5AGT should be placed in the genus Halomonas as a member of a novel species for which we propose the name Halomonas campaniensis sp. nov.

Phenotypic and phylogenetic studies were performed on unidentified Gram-negative staining, haloalkaliphilic aerobe and protease producer Salinivibrio-like organism recovered from a saltish spring with algal mat in the "Pozzo del Sale" site (Salt's Well) in the Campania Region (South Italy). Phylogenetic analysis based on comparison of 16S rRNA gene sequences demonstrated that the isolate was related to species of Salinivibrio genus. The DNA-DNA hybridization of the type strain 18AG(T) with the most related Salinivibrio costicola subsp. costicola showed a reassociation value of 72%. Based on the phenotypic distinctiveness of 18AG(T) strain and molecular, chemical and genetic evidence, it is proposed that strain 18AG(T) can be classified as S. costicola subsp. alcaliphilus, subsp. nov. The type strain of S. costicola subsp. alcaliphilus, is ATCC BAA-952(T); DSM 16359(T).

The taxomony of strain M8, isolated from algal mat formed at the origin of a sulfurous spring in Rifieto (Savignano Irpino, Campania, Italy), was investigated in a polyphasic approach. The morphological, physiological and genetic characteristics were compared with of Planococcus and Planomicrobium species. The isolate grew optimally at pH 9.0, 1.8 M NaCl at 37 degrees C. The cells were Gram-positive cocci that form pairs, tetrads and aggregates of several cells. The isolate was aerobic/microaerophilic and accumulated glycine-betaine, as a major osmolyte, with minor components glutamate and an unknown compound. M8 was able to hydrolyse X-Glc (5-bromo-4-chloro-3-indoyl beta-d-glucopyranoside). The polar lipid profile consisted of phosphatidylglycerol and diphosphatidylglycerol as major components, and phosphocholine as a minor compound. MK8 was the only quinone found and the fatty acid composition was dominated by branched acids, mainly aiC15:0. The G+C content of DNA was 47.9% and its phylogenetic position was established by 16S rRNA gene sequencing as a member of the genus Planococcus. The DNA/DNA similarity of M8 to the type species Planococcus citreus was less than 55%. For this reason and for physiological and chemotaxonomic features, it is proposed to create a new species Planococcus rifietensis sp. nov.

Thermophilic microorganisms (4001-4014), described as aerobic or facultatively anaerobic, endospore forming with growth optima temperatures in the range of 60 to 80 degrees C, have been isolated from hot marine springs around Ischia and from hydrothermal vents in the gulf of Naples. Mucous colonies are been selected for the recovery of new strains producing exopolysaccharides (EPS). To induce the biosynthesis of new exopolysaccharides, different sugars were tested as carbon sources in the media. The production of EPS in the strain 4009 reached 60 mg/l using trehalose as carbon source, increasing the yield of about 1000 fold. The 4001-EPS was a mannan with a molecular weight of 380.000 D and with a complex primary structure. In fact, the analysis of the permethylated polysaccharide in GC-MS, showed the presence of mannose, glucose, galactose, mannosamine in the relative ratio of 1:0.1:tr :tr, respectively. Nuclear magnetic resonance spectrum of the exopolysaccharide confirmed the presence of a repetitive unity formed by seven monosaccharides, six with alpha gluco/galacto configuration and one residue with beta conformation.

The effects of salinity, growth temperature, pH and composition of the medium on the accumulation of intracellular organic solutes, by nuclear magnetic resonance spectroscopy (NMR) in Halomonas pantelleriense were examined. The modulation of lipid pattern in different growth conditions was also reported. H. pantelleriense accumulated glycine betaine, ectoine, hydroxyectoine and glutamate. The type of osmoprotectant and the relative proportion depended on growth conditions. The main lipids identified by NMR studies were 1,2 diacylglycero-3-phosphorylethanolamine (PEA), 1,2 diacylglycero-3-phosphoryl-glycerol (PG) and cardiolipin, (DPG). The predominant fatty acids were C16:0 and C18:1, minor fatty acids were C16:1 and C18:0. The relative percentage of polar lipids and fatty acids were affected by growth conditions.

A thermophilic aerobic microorganism, able to produce two exocellular polysaccharides (EPS1 and EPS2), was isolated from a shallow hydrothermal vent at Vulcano island (Eolian Islands, Italy). EPS1 and EPS2 were based on mannose and glucose although in a different ratio. EPS2 possessed a trisaccharide repeating unit with a manno-pyranoside configuration. New isolate phenotype was studied by physiological and morphological observations, including biochemical and antimicrobial susceptibility tests (134). Previous analyses carried out on 87 field isolates and 8 thermophilic reference bacilli displayed low phenotypic similarity level (S(SM) = 65%) with Bacillus thermodenitrificans DSM 465. Optimal growth occurs at 65 degrees C and pH 7.0. Oxidase and catalase are negative. The guanine-plus-cytosine (G+C) content of DNA is 52.7%. Genotypic investigations demonstrated the diversity of the isolate with fifteen selected thermophilic Bacillus spp. when we compared the restriction patterns of the amplified 16S rDNA. The membrane lipids are based on fatty acids mainly belonging to the iso-family.