Blastococcus brunescens sp. nov., a member of the Geodermatophilaceae isolated from sandstone collected from the Sahara Desert in Tunisia.

The taxonomic position of strain BMG 8361T, isolated from sandstone collected in the Sahara Desert of Southern Tunisia, was refined through a polyphasic taxonomic investigation. Colonies of BMG 8361T were pale-orange coloured, irregular with a dry surface and produced a diffusible pink or brown pigment depending on media. The Gram-positive cells were catalase-positive and oxidase-negative. The strain exhibited growth at 10-40 °C and pH values ranging from 5.5 to 9.0, with optima at 28-35 °C and pH 6.5-8.0. Additionally, BMG 8361T demonstrated the ability to grow in the presence of up to 1 % NaCl (w/v) concentration. The peptidoglycan of the cell wall contained meso-diaminopimelic acid, glucose, galactose, xylose, ribose, and rhamnose. The predominant menaquinones consisted of MK-9(H4) and MK-9. The main polar lipids were phosphatidylcholine, phosphatidylinositol, glycophosphatidylinositol, diphosphatidylglycerol, phosphatidylethanolamine, and two unidentified lipids. Major cellular fatty acids were iso-C16 : 0, iso-C16 : 1 h, and C17 : 1 ω8c. Phylogenetic analyses based on both the 16S rRNA gene and whole-genome sequences assigned strain BMG 8361T within the genus Blastococcus. The highest pairwise sequence similarity observed in the 16S rRNA gene was 99.5 % with Blastococcus haudaquaticus AT 7-14T. However, when considering digital DNA-DNA hybridization and average nucleotide identity, the highest values, 48.4 and 86.58 %, respectively, were obtained with Blastococcus colisei BMG 822T. These values significantly undershoot the recommended thresholds for establishing new species, corroborating the robust support for the distinctive taxonomic status of strain BMG 8361T within the genus Blastococcus. In conjunction with the phenotyping results, this compelling evidence leads to the proposal of a novel species we named Blastococcus brunescens sp. nov. with BMG 8361T (=DSM 46845T=CECT 8880T) as the type strain.

Blastococcus tunisiensis sp. nov., isolated from limestone collected in Tunisia.

A new actinobacterium strain, designated BMG 823T, was isolated from a limestone sample collected in Tunisia. Its taxonomic position was scrutinized using a polyphasic approach. Colonies of strain BMG 823T were pink orange-coloured, regular and had a moist surface. Cells are Gram-stain-positive, catalase-negative and oxidase-negative. The strain grew at pH 5.5-9, 10-40 °C and in presence of up to 4 % NaCl (w/v). Chemotaxonomically, strain BMG 823T was characterized by cell-wall type III containing meso-diaminopimelic acid as diamino acid, glucose, ribose and rhamnose as whole-cell sugars, MK-9(H4) as predominant menaquinone, and phosphatidylcholine, diphosphadidylglycerol, phosphatidethanolamine, phosphatidylcholine, phosphatidylinositol, unidentified glycolipid, unidentified aminophospholipids and unidentified glycophospholipid as major polar lipids. The fatty acid profile consisted of iso-C16 : 0 and iso-C17 : 1 ω9. Phylogenetic trees based on 16S rRNA gene and genome sequences placed strain BMG 823T within the genus Blastococcus and separated it from all type strains of validly published species. Comparison of 16S rRNA gene sequence similarity, digital DNA-DNA hybridization and average nucleotide identity indicated that strain BMG 823T was most closely related to Blastococcus litoris DSM 106127T and Blastococcus colisei BMG 822T with pairwise values well below the species differentiation thresholds. The distinct phenotypic and genotypic features of strain BMG 823T (=DSM 46838T=CECT 8881T) within the genus Blastococcus warrant its recognition as the type strain for the new species for which we propose the name Blastococcus tunisiensis sp. nov.

Diversity of rhodopsins in cultivated bacteria of the family Geodermatophilaceae associated with non-aquatic environments.

MOTIVATION: A small amount of research is focused on investigation of rhodopsins in cultivated bacteria isolated from non-aquatic environments. Furthermore, the abundance of these proteins in strains from hot and arid habitats was not reported previously. Since there is an insignificant amount of such isolates, the enigmatic role of the rhodopsins in dry ecological niches is still poorly understood. The members of the family Geodermatophilaceae could be used as interesting objects to search for new rhodopsin genes that will provide novel insights into versatility and importance of these proteins in non-aquatic conditions. RESULTS: This is the first report of the abundance of different rhodopsins in cultivated bacteria isolated from hot and arid ecological niches. A total of 31 rhodopsin genes were identified in 51 analyzed genomes of strains belonging to the family Geodermatophilaceae. Overall, 88% of the strains harbouring rhodopsins are isolated from non-aquatic environments. It was found that 82% of strains belonging to the genus Geodermatophilus have at least one gene as compared to 38% of strains of other genera which contain rhodopsins. Analysis of key amino acids revealed two types of the studied proteins: DTE type (putative proton pump) and NDQ type (putative sodium pump). Proton pumps were divided into two subtypes (DTEW and DTEF) according to phylogenetic analysis and the presence of highly conserved tryptophan or phenylalanine at position 182. Among all studied rhodopsins DTEF subtype is the most unique one, identified only in this family. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

Rossellomorea arthrocnemi sp. nov., a novel plant growth-promoting bacterium used in heavy metal polluted soils as a phytoremediation tool.

Strain EAR8T is a root endophyte isolated from Arthrocnemum macrostachyum plants collected from the Odiel marshes, Huelva (Spain). It presented in vitro plant growth-promoting properties and improved the plant growth and heavy metal accumulation in polluted soils playing an important role in phytoremediation strategies. Phenotypically, strain EAR8T cells were Gram-positive, aerobic and non-motile rods with terminal oval endospores and non-swollen sporangia which form beige, opaque, butyrous, raised and irregular colonies with undulate margins. The strain was able to grow between 15-45 °C, at pH 6.0-9.0 and tolerated 0-25 % NaCl (w/v) showing optimal growth conditions on trypticase soy agar plates supplemented with 2.5 % NaCl (w/v) at pH 7.0 and 37 °C for 24 h. Chemotaxonomic analyses showed that the isolate has meso-diaminopimelic acid as the peptidoglycan in the cell wall and MK-7 as the major respiratory quinone. The predominant fatty acids were anteiso-C15 : 0 and iso-C15 : 0 and the polar lipid profile was composed of diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. Phylogenetic analyses based on the whole proteomes of closest sequenced relatives confirmed that strain EAR8T is affiliated to the genus Rossellomorea and forms a clade with Rossellomorea vietnamensis 15-1T with maximum support. Genome analyses showed that EAR8T has indole-3-acetic acid and siderophore biosynthesis and transporters genes and genes related to resistance against heavy metals. Phenotypic and phylogenomic comparative studies suggested that strain EAR8T is a new representative of the genus Rossellomorea and the name Rossellomorea arthrocnemi sp. nov. is proposed. Type strain is EAR8T (=CECT 9072T=DSM 103900T).

Modestobacter altitudinis sp. nov., a novel actinobacterium isolated from Atacama Desert soil.

Three presumptive Modestobacter strains isolated from a high altitude Atacama Desert soil were the subject of a polyphasic study. The isolates, strains 1G4T, 1G51 and 1G52, were found to have chemotaxonomic and morphological properties that were consistent with their assignment to the genus Modestobacter. They formed a well supported clade in Modestobacter 16S rRNA gene trees and were most closely related to the type strain of 'Modestobacter excelsi' (99.8-99.9% similarity). They were also closely related to the type strains of Modestobacter caceresii (99.6 % similarity), Modestobacter italicus (99.7-99.9% similarity), Modestobacter lacusdianchii (98.4-99.2% similarity), Modestobacter marinus (99.4-99.5% similarity) and Modestobacter roseus (99.3-99.5% similarity), but were distinguished from their closest relatives by a combination of phenotypic features. Average nucleotide identity and digital DNA:DNA hybridization similarities drawn from comparisons of draft genome sequences of isolate 1G4T and its closest phylogenetic neighbours mentioned above, were well below the threshold used to assign closely related strains to the same species. The close relationship between isolate 1G4T and the type strain of M. excelsi was showed in a phylogenomic tree containing representative strains of family Geodermatophilaceae. The draft genome sequence of isolate 1G4T (size 5.18 Kb) was shown to be rich in stress related genes providing further evidence that the abundance of Modestobacter propagules in Atacama Desert habitats reflects their adaptation to the harsh environmental conditions prevalent in this biome. In light of all of these data it is proposed that the isolates be assigned to a novel species in the genus Modestobacter. The name proposed for this taxon is Modestobacter altitudinis sp. nov., with isolate 1G4T (=DSM 107534T=PCM 3003T) as the type strain.

Pseudoalteromonas rhizosphaerae sp. nov., a novel plant growth-promoting bacterium with potential use in phytoremediation.

Strain RA15T was isolated from the rhizosphere of the halophyte plant Arthrocnemum macrostachyum growing in the Odiel marshes (Huelva, Spain). RA15T cells were Gram stain-negative, non-spore-forming, aerobic rods and formed cream-coloured, opaque, mucoid, viscous, convex, irregular colonies with an undulate margin. Optimal growth conditions were observed on tryptic soy agar (TSA) plates supplemented with 2.5 % NaCl (w/v) at pH 7.0 and 28 °C, although it was able to grow at 4-32 °C and at pH values of 5.0-9.0. The NaCl tolerance range was from 0 to 15 %. The major respiratory quinone was Q8 but Q9 was also present. The most abundant fatty acids were summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c), C17 : 1 ω8c and C16 : 0. The polar lipids profile comprised phosphatidylglycerol and phosphatidylethanolamine as the most abundant representatives. Phylogenetic analyses confirmed the well-supported affiliation of strain RA15T within the genus Pseudoalteromonas, close to the type strains of Pseudoalteromonas neustonica, Pseudoalteromonas prydzensis and Pseudoalteromonas mariniglutinosa. Results of comparative phylogenetic and phenotypic studies between strain RA15T and its closest related species suggest that RA15T could be a new representative of the genus Pseudoalteromonas, for which the name Pseudoalteromonas rhizosphaerae sp. nov. is proposed. The type strain is RA15T (=CECT 9079T=LMG 29860T). The whole genome has 5.3 Mb and the G+C content is 40.4 mol%.

Halomonas radicis sp. nov., isolated from Arthrocnemum macrostachyum growing in the Odiel marshes(Spain) and emended descriptions of Halomonas xinjiangensis and Halomonas zincidurans.

Strain EAR18T was isolated as an endophyte from the roots of a halophyte plant, Arthrocnemum macrostachyum, growing in the Odiel marshes (Huelva, Spain). Cells of strain EAR18T were Gram- stain-negative, motile, non-spore-forming aerobic rods. It grew optimally on tryptic soy agar supplemented with 2.5 % NaCl (w/v), at pH 7 and 30 °C for 48 h. It tolerated NaCl from 0 to 25 % (w/v). It presented Q9 as the major quinone and C19 : 0 cyclo ω8c, summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c) and C16 : 0 as the predominant fatty acids. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and four unidentified phospholipids. The results of phylogenetic analysis based on 16S rRNA gene sequences revealed that strain EAR18T formed a well-supported clade with species Halomonas zincidurans B6T and Halomonas xinjiangensis TRM 0175T (similarities of 98.3 and 96.1 % respectively). Furthermore, digital DNA-DNA hybridization analysis resulted in values of 20.4 % with H. xinjiangensis TRM 0175T and 35.50 % with H. zincidurans B6T, and ANIb/ANIm results in values of 73.8 %/84.2 % with H. xinjiangensis TRM 0175T and 86.8 %/89.4 % with H. zincidurans B6T. Based on phylogeny and differential phenotypic properties in comparison with its closest related species, strain EAR18T is suggested to represent a new species in the genus Halomonas, for which the name Halomonas radicis sp. nov. is proposed. The type strain is EAR18T (=CECT 9077T=LMG 29859T). The whole genome was sequenced, and it had a total length of 4.6 Mbp and a G+C content of 64.9 mol%.

Modestobacter italicus sp. nov., isolated from Carrara marble quarry and emended descriptions of the genus Modestobacter and the species Modestobacter marinus, Modestobacter multiseptatus, Modestobacter roseus and Modestobacter versicolor.

A Gram-reaction-positive, aerobic bacterial strain showing coccoid cells and designated as BC 501T was isolated from a black patina of the surface of a Carrara marble blockin the Gioia quarry in Tuscany, Italy. A polyphasic study was carried out to clarify the taxonomic status of BC 501T within the evolutionary radiation of the genus Modestobacter. Phenotypic and genotypic characteristics as well as phylogenetic distinctiveness confirmed that it represents a novel species of the genus Modestobacter, for which the name Modestobacteritalicus sp. nov. is proposed. The type strain is BC 501T (=DSM 44449T=CECT 9708T). Emended descriptions of the genus Modestobacter and the species Modestobacter marinus, Modestobacter multiseptatus, Modestobacter roseus and Modestobacter versicolor are also proposed.

Blastococcus xanthinilyticus sp. nov., isolated from monument.

A novel, non-motile, coccoid, Gram-stain-positive actinobacterium, designated BMG 862T, was isolated from a marble sample collected from the Bulla Regia monument, Northern Tunisia. Its taxonomic position was determined using a polyphasic approach. Results from chemotaxonomic analyses showed MK-9(H4), MK-8(H4) and MK-9(H2) as the predominant menaquinones. The major polar lipids comprised diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, glycophosphatidylinositol, hydroxy-phosphatidylethanolamine and three unidentified phospholipids. The fatty acids consisted of significant amounts (≥10 %) of iso-C16 : 0, C17 : 1ω8c, iso-C15 : 0 and C16 : 1ω7c. Phylogenetic analysis on the basis of 16S rRNA gene sequence comparisons showed that strain BMG 862T belongs to the genus Blastococcus, being most closely related to Blastococcus saxobsidens (=DSM 44509T) (99.5 %) and Blastococcus capsensis (=DSM 46835T=CECT 8876T) (99.3 %). The genomic DNA G+C content of the organism was 74.7 mol%. Results of DNA-DNA hybridization and physiological tests allowed differentiation of strain BMG 862T from related species. The strain was also characterized by its ability to hydrolyse xanthine. On the basis of phenotypic and molecular characteristics, strain BMG 862T (=DSM 46842T=CECT 8884T) represents the type strain of a novel species of the genus Blastococcus, for which the name Blastococcus xanthinilyticus sp. nov. is proposed.

Blastococcus atacamensis sp. nov., a novel strain adapted to life in the Yungay core region of the Atacama Desert.

A polyphasic study was undertaken to establish the taxonomic status of a Blastococcus strain isolated from an extreme hyper-arid Atacama Desert soil. The isolate, strain P6T, was found to have chemotaxonomic and morphological properties consistent with its classification in the genus Blastococcus. It was shown to form a well-supported branch in the Blastococcus 16S rRNA gene tree together with the type strains of Blastococcus capsensis and Blastococcus saxobsidens and was distinguished from the latter, its close phylogenetic neighbour, by a broad range of phenotypic properties. The draft genome sequence of isolate P6T showed 84.6 % average nucleotide identity, 83.0 % average amino acid identity and a digital DNA-DNA hybridisation value of 27.8 % in comparison with the genome sequence of B. saxobsidens DSM 44509T, values consistent with its assignment to a separate species. Based on these data it is proposed that isolate P6T (NCIMB 15090T=NRRL B-65468T) be assigned to the genus Blastococcus as Blastococcus atacamensis sp. nov. Analysis of the whole genome sequence of B. atacamensis P6T, with 3778 open reading frames and a genome size of 3.9 Mb showed the presence of genes and gene clusters that encode for properties that reflect its adaptation to the extreme environmental conditions that prevail in Atacama Desert soils.

Kushneria phyllosphaerae sp. nov. and Kushneria endophytica sp. nov., plant growth promoting endophytes isolated from the halophyte plant Arthrocnemum macrostachyum.

Two endophytic bacteria (EAod3T and EAod7T) were isolated from the aerial part of plants of Arthrocnemum macrostachyum growing in the Odiel marshes (Huelva, Spain). Phylogenetic analysis based on 16S rRNA gene sequences indicated their affiliation to the genus Kushneria. 16S rRNA gene sequences of strains EAod3T and EAod7T showed the highest similarity to Kushneria marisflavi DSM 15357T (99.0 and 97.6 %, respectively). Digital DNA-DNA hybridization studies between the draft genomes of strain EAod3T and K. marisflavi DSM 15357T corresponded to 28.5 % confirming the novel lineage of strain EAod3T in the genus Kushneria. Cells of both strains were Gram-staining-negative, aerobic and motile rods able to grow at 4-37 °C, at pH 5.0-8.0 and tolerate 0.5-25 % NaCl (w/v). They presented ubiquinone Q9 and C16 : 0, C16 : 1ω7c/C16 : 1ω6c and C18 : 1ω7c as the major fatty acids. The predominant polar lipids were diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. Based on the phenotypic and phylogenetic results, strains EAod3T (=CECT 9073T=LMG 29856T) and EAod7T (=CECT 9075T=LMG 29858T) are proposed as new representatives of the genus Kushneria, and the proposed names are Kushneria phyllosphaerae sp. nov. and Kushneria endophytica sp. nov., respectively. The whole genome sequence of strain EAod3T has a total length of 3.8 Mbp and a G+C content of 59.3 mol%.

Promicromonospora kermanensis sp. nov., an actinobacterium isolated from soil.

A novel strain belonging to the genus Promicromonospora, designated HM 533T, was isolated from soil in Kerman Province, Iran. It produced long and branched hyphae on ISP 2 medium that developed into a large number of irregular-shaped spores. It showed optimal growth at 25-30 °C and pH 5.0-8.0 with 0-4 % (w/v) NaCl. The peptidoglycan type of strain HM 533T was A4α l-Lys-l-Ala-d-Glu. Whole-cell hydrolysates of strain HM 533T contained the sugars ribose, glucose and galactose. The main phospholipids were phosphatidylglycerol, diphosphatidylglycerol, phosphatidylinositol, two unknown glycolipids and an unknown phospholipid. MK-9(H4) and MK-9(H2) were the predominant menaquinones. The fatty acids pattern was mainly composed of the saturated branched-chain acids anteiso-C15 : 0 and iso-C15 : 0. The 16S rRNA gene sequence analysis showed the highest pairwise sequence identity (99.5-97.1 %) with the members of the genus Promicromonospora. Based on phenotypic and genotypic features, strain HM 533T is considered to represent a novel species of the genus Promicromonospora, for which the name Promicromonospora kermanensis is proposed with strain HM 533T (=DSM 45485T=UTMC 00533T=CECT 8709T) as the type strain.

Kocuria salina sp. nov., an actinobacterium isolated from the rhizosphere of the halophyte Arthrocnemum macrostachyum and emended description of Kocuria turfanensis.

A novel, non-motile coccoid, Gram-positive and non-endospore forming bacterium, designated Hv14bT, was isolated from the rhizosphere of the halophyte Arthrocnemum macrostachyum. It was observed to be catalase positive and oxidase negative and able to hydrolyse starch. MK-8(H2) was identified as the dominant menaquinone and the major cellular fatty acids were anteiso-C15 : 0 and iso-C15 : 0. The polar lipids comprised diphosphatidylglycerol, phosphatidylglycerol and an unidentified glycolipid. The 16S rRNA genes showed the highest 16S rRNA sequence identity with K. polaris DSM 14382T, K. rosea DSM 20447T and K. turfanensis DSM 22143T. Based on the phenotypic and molecular features and DNA-DNA hybridization data, it is concluded that strain Hv14bT is proposed to represent a novel species in the genus Kocuria, Kocuria salina sp. nov., with the type strain Hv14bT=DSM 28714T=CECT 9229T.

Two novel species of rapidly growing mycobacteria: Mycobacterium lehmannii sp. nov. and Mycobacterium neumannii sp. nov.

Two rapidly growing mycobacteria with identical 16S rRNA gene sequences were the subject of a polyphasic taxonomic study. The strains formed a well-supported subclade in the mycobacterial 16S rRNA gene tree and were most closely associated with the type strain of Mycobacterium novocastrense. Single and multilocus sequence analyses based on hsp65, rpoB and 16S rRNA gene sequences showed that strains SN 1900T and SN 1904T are phylogenetically distinct but share several chemotaxonomic and phenotypic features that are are consistent with their classification in the genus Mycobacterium. The two strains were distinguished by their different fatty acid and mycolic acid profiles, and by a combination of phenotypic features. The digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) values for strains SN 1900T and SN 1904T were 61.0 % and 94.7 %, respectively; in turn, the corresponding dDDH and ANI values with M. novocastrense DSM 44203T were 41.4 % and 42.8 % and 89.3 % and 89.5 %, respectively. These results show that strains SN1900T and SN 1904T form new centres of taxonomic variation within the genus Mycobacterium. Consequently, strains SN 1900T (40T=CECT 8763T=DSM 43219T) and SN 1904T (2409T=CECT 8766T=DSM 43532T) are considered to represent novel species, for which the names Mycobacteriumlehmannii sp. nov. and Mycobacteriumneumannii sp. nov. are proposed. A strain designated as 'Mycobacteriumacapulsensis' was shown to be a bona fide member of the putative novel species, M. lehmannii.

Blastococcus colisei sp. nov, isolated from an archaeological amphitheatre.

The taxonomic position of an actinobacterial isolate, designated strain BMG 822T, isolated from limestone from the Amphitheater of El Jem (Coliseum Thysdrus), Tunisia, was established using a polyphasic approach. Strain BMG 822T was found to grow well at 30 °C and pH 6.5-8.0, and to be coral-coloured, Gram-positive, catalase and oxidase negative. Whole cell hydrolysates contained meso-diaminopimelic acid as the diagnostic diamino acid, glucose, galactose and ribose. The phospholipids detected were diphosphatidylglycerol, phosphatidylcholine, phosphatidylinositol, phosphatidylethanolamine, hydroxy-phosphatidylethanolamine, an unidentified glycophospholipid and six unidentified phospholipids. MK-9(H4) was found to be the predominant menaquinone, followed by MK-9(H2) and MK-9. The major cellular fatty acids were identified as iso-C16:0, C18:1 ω9c, C17:1 ω8c and iso-H-C16:1. The G+C content of the DNA (73.2%) is typical of the genus. High degrees of 16S rRNA gene sequence similarity were found with the type strains of the genus Blastococcus (97.1-98.3%) followed by the type strains of Modestobacter (96.8-97.8%). Based on the above data and the phenotypic differences from the type strains of Blastococcus species, it is proposed that the isolate BMG 822T (=DSM 46837T=CECT 8823T) should be classified as the type strain of a novel species, Blastococcus colisei sp. nov.

Geodermatophilus pulveris sp. nov., a gamma-radiation-resistant actinobacterium isolated from the Sahara desert.

A black-pigmented, aerobic actinobacterium, tolerant to ionizing radiation, designated BMG 825T, was isolated from desert limestone dust in Tunisia. The strain grew within the temperature range 10-40 °C, at pH 5.5-11.0 and in the presence of 2 % NaCl. The DNA G+C content was 75.7 mol%, and its cell-wall peptidoglycan contained meso-diaminopimelic acid. Sugars of whole-cell hydrolysates were galactose, glucose, and trace amounts of ribose and mannose. The predominant menaquinone was MK-9(H4), and the major fatty acids were iso-C16 : 0 and C16 : 1ω7c. The polar lipid profile comprised phosphatidylcholine, phosphatidylinositol, diphosphatidylglycerol, phosphatidylethanolamine, hydroxyphosphatidylethanolamine and an unspecified glycolipid. 16S rRNA gene sequence analysis revealed that the strain fell into the genus Geodermatophilus, showing the highest similarity with Geodermatophilus poikilotrophus DSM 44209T (99.1 %). DNA-DNA hybridization results, phylogenetic distinctiveness and phenotypic properties supported the classification of this strain as a representative of a novel species of the genus Geodermatophilus, for which the name Geodermatophilus pulveris sp. nov. is proposed. The type strain is BMG 825T (=CECT 9003T=DSM 46839 T).

Labrenzia salina sp. nov., isolated from the rhizosphere of the halophyte Arthrocnemum macrostachyum.

A novel, halophilic, motile, rod-shaped, Gram-staining-negative and non-endospore forming bacterium, designated Cs25T, was isolated from the rhizosphere of the halophyte Arthrocnemum macrostachyum growing in a tidal flat. Strain Cs25T was observed to be catalase-negative and oxidase-positive, and to hydrolyse hypoxanthine. Growth occurred from 15 to 40 °C, at pH 7.0-10.0 and with 1-11 % (w/v) NaCl. Q-10 was identified as the dominant ubiquinone, and the major cellular fatty acids were C18 : 1ω7c, 11-methyl C18 : 1ω7c, C20 : 1ω7c and C18 : 0. The polar lipids comprised phosphatidylmonomethylethanolamine, phosphatidylcholine, sulphoquinovosyldiacylglyceride, diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. The 16S rRNA gene showed 99.19, 98.6 and 98.59 % sequence identity with Labrenzia alba DSM 18320T, L. aggregata DSM 13394T and L. marina DSM 17023T, respectively. Based on the phenotypic and molecular features and DNA-DNA hybridization data, it is concluded that strain Cs25T represents a novel species for which the name Labrenzia salinasp. nov. is proposed. The type strain is Cs25T (=DSM 29163T=CECT 8816T).

Blastococcus capsensis sp. nov., isolated from an archaeological Roman pool and emended description of the genus Blastococcus, B. aggregatus, B. saxobsidens, B. jejuensis and B. endophyticus.

A novel Gram-reaction-positive actinobacterium, designated BMG 804T, was isolated from an archaeological Roman pool located in Gafsa, Tunisia. The strain grew as dry bright orange colonies at 30 °C and pH 6.0-8.0. It contained meso-diaminopimelic acid in the cell wall. The whole-cell sugars consisted of glucose, rhamnose and ribose. Polar lipids present were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, phosphatidylinositol, an unidentified glycolipid and two unidentified phospholipids. MK-9(H4) was the predominant menaquinone. The fatty acid profile contained major amounts (>5 %) of C17 : 1ω8c, C16 : 1ω7c, iso-C15 : 0, iso-C16 : 0 and iso-C16 : 1H. The 16S rRNA gene sequence of BMG 804T showed 99.4 % as highest sequence similarity with Blastococcussaxobsidens. DNA-DNA hybridization between strain BMG 804T and B.saxobsidens DSM 44509T was 48.6±6.6 %. The G+C content of the DNA was 73.7 mol%. On the basis of the phenotypic and genotypic characteristics, including DNA-DNA hybridization results, BMG 804T (=DSM 46835T=CECT 8876T) is proposed as the type strain of a novel species Blastococcuscapsensis sp. nov. Emended descriptions of the genus Blastococcus and the species Blastococcus aggregatus, B. saxobsidens, Blastococcus jejuensis and Blastococcus endophyticus are also proposed.

Proposal of a type strain for Frankia alni (Woronin 1866) Von Tubeuf 1895, emended description of Frankia alni, and recognition of Frankia casuarinae sp. nov. and Frankia elaeagni sp. nov.

Before the establishment of pure cultures, the species Frankia alni, 'Frankia casuarinae' and 'Frankia elaeagni' were proposed to encompass all causal agents of the nitrogen-fixing root nodules of dicotyledonous plants from the genera Alnus, Casuarina or Elaeagnus. The sole Frankia species with a validly published name, the type species F. alni, was described by Woronin (1866) as present in the root of alder. Until now no type strain has been designated for F. alni, even though the absence of a type strain has seriously inhibited the application of modern taxonomic methods to the genus Frankia. Thus, we propose that strain ACN14aT, isolated in pure culture from Alnus viridis ssp. crispa with morphological properties matching the original description of F. alni, be recognized as the type strain of this species according to Rule 18f of the International Code of Nomenclature of Bacteria. We compared ACN14aT to two strains, CcI3T and BMG5.12T, isolated from Casuarina cunninghamiana and Elaeagnus angustifolia, respectively, based on chemotaxonomy, phenotype microarray data and molecular data retrieved from genome sequences. All three tested strains grew as branched hyphae, produced vesicles and multilocular sporangia containing non-motile spores and metabolized short fatty acids, TCA-cycle intermediates and carbohydrates. Chemotaxonomically, the three strains were indistinguishable with respect to phospholipids (phosphatidylinositol, diphosphatidylglycerol, glycophospholipids and phosphatidylglycerol) and cell-sugar composition (glucose, mannose, ribose, rhamnose, galactose and xylose, with the latter two being diagnostic for the genus). The major fatty acids identified in all three strains were iso-C16 : 0, C17 : 1ω8c, C15 : 0, C17 : 0 and C16 : 0. ACN14aT and BMG5.12T also shared C15 : 1ω6c, while C18 : 1ω9c was found to be unique to BMG5.12T. The major menaquinones identified in all three novel type strains were MK-9(H8), MK-9(H6) and MK-9(H4). MK-9(H2) was shared by ACN14aT and BMG5.12T, while MK-10(H4) and MK-8(H4) were only found in BMG5.12T. Analysis of 16S rRNA gene sequences showed 98.1-98.9 % identity between strains ACN14aT, CcI3T and BMG5.12T. Digital DNA-DNA hybridization values between the three type strains were well below 70 %. These results confirm the separation of the strains into three distinct species, Frankia alni, Frankia casuarinae sp. nov. and Frankia elaeagni sp. nov. Thus, we propose ACN14aT (=DSM 45986T=CECT 9034T), CcI3T (=DSM 45818T=CECT 9043T) and BMG5.12T (=DSM 46783T=CECT 9031T) as the respective type strains.