Complete Genome Sequence of Nocardia iowensis DSM 45197T (= NRRL 5646T).

We report the complete genome sequence and predicted functional profile of Nocardia iowensis DSM 45197T. N. iowensis DSM 45197T is a spore-forming, mesophilic, Gram-positive bacterium that was isolated from garden soil in Osceola, Iowa, USA. This organism has been exploited for its production of glycocinnamolyspermidine antibiotics and biotransformation of xenobiotic substances. Other significant features of N. iowensis DSM 45197T include the first fully characterized carboxylic acid reductase (CAR) and the first bacterial nitric oxide synthase system. The genome sequence of N. iowensis DSM 45197T can facilitate further understanding of its function, as well as the pathogenesis of Nocardia spp. N. iowensis DSM 45197T has a genome size of 8.95 Mbp; about 46% of the coding sequences have no known homologues and were labeled hypothetical proteins. This finding implies further potential for biomedical and biotechnological research applications.

Complete Genome Sequence and Manual Reannotation of Mycobacterium avium subsp. paratuberculosis Strain DSM 44135.

Here, we report the complete genome sequence of the Mycobacterium avium subsp. paratuberculosis reference strain DSM 44135, amended with a manual genome reannotation. The strain was originally described as M. paratuberculosis strain 6783. It was isolated from feces from a dairy cow in northern Germany.

Sequencing orphan species initiative (SOS): Filling the gaps in the 16S rRNA gene sequence database for all species with validly published names.

High quality 16S ribosomal RNA (rRNA) gene sequences from the type strains of all species with validly published names, as defined by the International Code of Nomenclature of Bacteria, are a prerequisite for their accurate affiliations within the global genealogical classification and for the recognition of potential new taxa. During the last few years, the Living Tree Project (LTP) has taken care to create a high quality, aligned 16S and 23S rRNA gene sequence database of all type strains. However, the manual curation of the sequence dataset and type strain information revealed that a total of 552 "orphan" species (about 5.7% of the currently classified species) had to be excluded from the reference trees. Among them, 322 type strains were not represented by an SSU entry in the public sequence repositories. The remaining 230 type strains had to be discarded due to bad sequence quality. Since 2010, the LTP team has coordinated a network of researchers and culture collections in order to improve the situation by (re)-sequencing the type strains of these "orphan" species. As a result, we can now report 351 16S rRNA gene sequences of type strains. Nevertheless, 201 species could not be sequenced because cultivable type strains were not available (121), the cultures had either been lost or were never deposited in the first place (66), or it was not possible due to other constraints (14). The International Code of Nomenclature of Bacteria provides a number of mechanisms to deal with the problem of missing type strains and we recommend that due consideration be given to the appropriate mechanisms in order to help solve some of these issues.

A new extreme environment for aerobic anoxygenic phototrophs: biological soil crusts.

Biological soil crusts improve the health of arid or semiarid soils by enhancing water content, nutrient relations and mechanical stability, facilitated largely by phototrophic microorganisms. Until recently, only oxygenic phototrophs were known from soil crusts. A recent study has demonstrated the presence of aerobic representatives of Earth's second major photosynthetic clade, the evolutionarily basal anoxygenic phototrophs. Three Canadian soil crust communities yielded pink and orange aerobic anoxygenic phototrophic strains possessing the light-harvesting pigment bacteriochlorophyll a. At relative abundances of 0.1-5.9% of the cultivable bacterial community, they were comparable in density to aerobic phototrophs in other documented habitats. 16S rDNA sequence analysis revealed the isolates to be related to Methylobacterium, Belnapia, Muricoccus and Sphingomonas. This result adds a new type of harsh habitat, dry soil environments, to the environments known to support aerobic anoxygenic phototrophs.

A new environment for aerobic anoxygenic phototrophic bacteria: biological soil crusts.

Phototrophic microorganisms are critical to the carbon cycling and productivity of biological soil crusts, which enhance water content, nutrient relations and mechanical stability of arid soils. Only oxygen-producing phototrophs, including cyanobacteria and algae, are known from soil crusts, but Earth's second major branch of photosynthetic organisms, the evolutionarily earlier anoxygenic phototrophs, is unreported. We announce the discovery of aerobic anoxygenic phototrophs in three Canadian soil crust communities. We found in a culture-based study that they comprised 0.1-5.9% of the cultivable bacterial community in moss-, lichen- and cyanobacteria-dominated crust from sand dunes and sandy soils. Comparable in density to aerobic phototrophs in other habitats, the bacteriochlorophyll a-possessing pink and orange isolates were related to species of Methylobacterium (99.0-99.5%), Belnapia (97.4-98.8%), Muricoccus (94.4%) and Sphingomonas (96.6-98.5%), based on 16S rRNA gene sequences. Our results demonstrate that proteobacterial anoxygenic phototrophs may be found in dry soil environments, implying desiccation resistance as yet unreported for this group. By utilizing sunlight for part of their energy needs, aerobic phototrophs can accelerate organic carbon cycling in nutrient-poor arid soils. Their effects will be especially important as global climate change enhances soil erosion and consequent nutrient loss.

Description of Ancylobacter oerskovii sp. nov. and two additional strains of Ancylobacter polymorphus.

A Gram-negative, pleomorphic, rod-shaped, non-spore-forming bacterium, designated strain NS05T, was isolated from soil after enrichment with oxalate. On the basis of 16S rRNA gene sequence similarity, strain NS05T was shown to be phylogenetically related to the genera Ancylobacter, Starkeya and Angulomicrobium (96.3-98.1% sequence similarity), class Alphaproteobacteria. Strain NS05T was most closely related to Ancylobacter rudongensis AS 1.1761T (98.1% sequence similarity). The whole-cell fatty acid pattern of strain NS05T was typical of those found in members of the genus Ancylobacter. Its main components were C(18:1)omega7c (60.4%), C(19:0)omega8c cyclo (28.3%) and C(16:0) (7.4%) and hydroxylated compounds were absent. The results of DNA-DNA hybridization and physiological and biochemical tests allowed genotypic and phenotypic differentiation of strain NS05T with respect to the four Ancylobacter species with validly published names. Therefore, it is concluded that NS05T represents a novel species of the genus Ancylobacter, for which the name Ancylobacter oerskovii sp. nov. is proposed. The type strain is NS05T (=DSM 18746T=CCM 7435T). Two other oxalate-utilizing strains, NS03 and NS04, isolated from paper-mill effluents, were shown by 16S rRNA gene sequence analysis to be affiliated to the species Ancylobacter polymorphus. The study of their physiological properties extends the knowledge of the physiological variability within this species.

Novel halophilic aerobic anoxygenic phototrophs from a Canadian hypersaline spring system.

The first enumeration of cultivable obligately aerobic phototrophic bacteria from a terrestrial saline spring was accomplished in the East German Creek system (salinity approximately 6%), near Lake Winnipegosis, Manitoba, Canada. Occurring at densities up to 3.3x10(7) CFU/ml of sample, aerobic phototrophs comprised 15-36% of the total cultivable bacterial population in the diatom- and chlorophyte-dominated aerobic microbial mats. Many of the representative strains isolated for phenotypic characterization and phylogenetic analysis possessed <96% 16S rDNA sequence overlap with published species, including an obligately aerobic phototrophic gammaproteobacterium displaying only 92.9% 16S rDNA sequence similarity to Congregibacter litoralis. The springs yielded the most highly halotolerant aerobic anoxygenic phototroph yet recorded, strain EG11, which grew with 26% NaCl.

Herminiimonas saxobsidens sp. nov., isolated from a lichen-colonized rock.

A Gram-negative, rod-shaped, non-spore-forming bacterium (strain NS11T) was isolated from a lichen-colonized rock surface. On the basis of 16S rRNA gene sequence similarity, strain NS11T was shown to belong to the Betaproteobacteria, and was most closely related to Herminiimonas arsenicoxydans ULPAs1T (98.8%), Herminiimonas aquatilis CCUG 36956T (98.0%) and Herminiimonas fonticola S-94T (98.0%). Major whole-cell fatty acids were C16:0, C17:0 cyclo and C16:1omega7c. Strain NS11T also contained high proportions of C10:0 3-OH and C18:1omega7c. This pattern is typical for members of the genus Herminiimonas. The results of DNA-DNA hybridization experiments and physiological and biochemical tests allowed genotypic and phenotypic differentiation of strain NS11T from the three recognized Herminiimonas species. It is therefore concluded that strain NS11T represents a novel species of the genus Herminiimonas, for which the name Herminiimonas saxobsidens sp. nov. is proposed. The type strain is NS11T (=DSM 18748T=CCM 7436T).

A novel species of Xenorhabdus, family Enterobacteriaceae: Xenorhabdus indica sp. nov., symbiotically associated with entomopathogenic nematode Steinernema thermophilum Ganguly and Singh, 2000.

In the search for novel Xenorhabdus strains in a recently described nematode species, Steinernema thermophilum, three strains (strain 28(T) = DSM 17382(T), strain 42 = DSM 17383 and strain 43 = DSM 17384) were isolated from three independent isolation approaches from crushed mixture of infective juveniles. 16S rRNA gene sequence comparison of strains 28(T) and DSM 17383 indicated identity and the phylogenetic position pointed towards an individual taxon within the phylogenetic dendrogram of Xenorhabdus type strains. The nearest phylogenetic relatives of strain 28(T) were Xenorhabdus poinarii and Xenorhabdus szentirmaii (97.7% each). The three isolates were almost identical in reaction towards the API and BIOLOG substrate panels but differed in their reactions from those of the established type strains of the genus Xenorhabdus. These clear genomic and metabolic differences let us propose a new species, Xenorhabdus indica sp. nov. for the three clones. The type strain is strain 28(T), DSM 17382(T), CIP 108830(T).

Diversity, distribution and physiology of the aerobic phototrophic bacteria in the mixolimnion of a meromictic lake.

The population of anoxygenic phototrophic bacteria in the aerobic zone of the meromictic Mahoney Lake was investigated using classical microbiological methods. This bacterial community was found to be very rich and diverse. Thirty-one new strains of the obligately aerobic phototrophic bacteria, and two new purple nonsulfur strains, were isolated in pure cultures and preliminarily characterized. The isolates contain a variety of carotenoids, bacteriochlorophyll a incorporated into pigment protein complexes, and are morphologically and physiologically diverse. These properties indicate a diversity of adaptations to the stratified environments of this meromictic lake. Phylogenetically all isolated strains belong to the alpha subclass of Proteobacteria.