Reassessment of the systematics of the suborder Pseudonocardineae: transfer of the genera within the family Actinosynnemataceae Labeda and Kroppenstedt 2000 emend. Zhi et al. 2009 into an emended family Pseudonocardiaceae Embley et al. 1989 emend. Zhi et al. 2009

Actinophytocola gossypii sp. nov. and Streptomyces gossypii sp. nov., two novel actinomycetes isolated from rhizosphere soil of cotton

Two Gram-positive, aerobic and non-motile actinomycetes, designated S1-96^T and N2-109^T, were isolated from soils collected from a cotton field. They are described as representing two novel species of genera Actinophytocola and Streptomyces through a polyphasic approach. Analysis of 16S rRNA gene sequences revealed that strains S1-96^T and N2-109^T showed highest similarity to Actinophytocola xinjiangensis CGMCC 4.4663^T (99.10 %) and Streptomyces iconiensis BNT558^T (98.21 %), respectively. Phylogenetic analyses based on 16S rRNA and core genes confirmed the close relationships of these strains. Genomic analyses further supported the novel taxonomic delimitation of these two species based on digital DNA-DNA hybridization and average nucleotide identity. Strains S1-96^T and N2-109^T contained MK-9(H₄) and MK-9(H₆) as the most abundant menaquinone, respectively. High abundances of iso-fatty acids were detected in both strains, which was similar to their close relatives. Physiological and polar lipid analyses also revealed differences between these strains and their phylogenetic neighbours, supporting their taxonomic delimitation as novel species. The names Actinophytocola gossypii sp. nov. (type strain S1-96^T=JCM 34412^T=CGMCC 4.7707^T) and Streptomyces gossypii sp. nov. (type strain N2-109^T=JCM 34628^T=CGMCC 4.7717^T) are proposed.

Solihabitans fulvus gen. nov., sp. nov., a member of the family Pseudonocardiaceae isolated from soil

A polyphasic taxonomic study was carried out on an actinobacterial strain (AN110305T) isolated from soil sampled in the Republic of Korea. Cells of the strain were Gram-stain-positive, aerobic, non-motile and rod-shaped. Comparative 16S rRNA gene sequence studies showed a clear affiliation of strain AN110305T with Actinomycetia , with highest pairwise sequence similarities to Goodfellowiella coeruleoviolacea DSM 43935T (97.6%), Umezawaea tangerina MK27-91F2T (97.0%), Kutzneria chonburiensis NBRC 110610T (96.9%), Kutzneria buriramensis A-T 1846T (96.8%), Umezawaea endophytica YIM 2047XT (96.8%), Kutzneria albida NRRL B-24060T (96.7%) and Saccharothrix coeruleofusca NRRL B-16115T (96.6%). Cells of strain AN110305T formed pale-yellow colonies on Reasoner's 2A agar. MK-9 (H4) (68%) and MK-10 (H4) (32%) were the predominant menaquinones. Diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylmethyl ethanolamine, hydroxy-phosphatidylethanolamine, an unidentified aminolipid and an unidentified aminophospholipid were major polar lipids. Iso-C16:0 (24.5%), anteiso-C15:0 (19.3%), anteiso-C17:0 (15.7%) and iso-C15:0 (15.2%) were the major fatty acids and meso-diaminopimelic acid was the pepdidoglycan. The cell-wall sugars were composed of galactose, glucose, mannose and ribose. The genomic DNA G+C content was 70.7 mol%. Based on genotypic and phenotypic data, strain AN110305T could be distinguished from all genera within the family Pseudonocardiaceae and represents a novel genus and species named Solihabitans fulvus gen. nov., sp nov. The type strain is AN110305T (=KCTC 39307T =DSM 103572T).

Qaidamihabitans albus gen. nov., sp. nov., a new member of the family Pseudonocardiaceae, and transfer of Prauserella shujinwangii to Qaidamihabitans gen. nov. as Qaidamihabitans shujinwangii comb. nov

A novel mycelium-forming actinomycete strain, designated YIM S01255^T were isolated from a salt lake. Optimal growth occurred in the presence of 0-5.0% (w/v) NaCl, at pH 7.0-8.0, and at 37 °C. Strain YIM S01255^T contained meso-diaminopimelic acid as the diagnostic diamino acid, and glucose, galactose and arabinose as the whole-cell sugars. The major fatty acid (> 5.0%) were iso-C_16:0, iso-C_16:1H and iso-C_15:0. The major menaquinone were MK-9(H₄) and MK-8(H₄). The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylmonomethylethanolamine, phosphatidylinositolmannoside and phosphatidylinositol. The DNA G + C content was 70.7 mol%. The 16S rRNA gene sequence of the strain showed high similarity to members of genera in the family Pseudonocardiaceae with values less than 95.8%, and most closely related to the genus Amycolatopsis. Both of phylogenetic analysis based on 16S rRNA gene sequences and the up-to-date bacterial genome sequences analysis revealed that strains YIM S01255^T and Prauserella shujinwangii XJ46^T formed a distinct monophyletic clade and was separated from the other members within the family Pseudonocardiaceae. The average nucleotide identity (ANI) values and digital DNA-DNA hybridization (dDDH) between the two strains were 81.0% and 40.6%, respectively. The distinctive polyphasic evidences differentiated YIM S01255^T from members of the family Pseudonocardiaceae, so strain YIM S01255^T is considered to represent a novel species of a novel genus of the family Pseudonocardiaceae, for which the name Qaidamihabitans albus gen. nov., sp. nov. is proposed. The type strain of genus Qaidamihabitans is YIM S01255^T (= KCTC 49476^T = CGMCC 4.7684^T). Moreover, Prauserella shujinwangii is also proposed to being transferred into the genus Qaidamihabitans as Qaidamihabitans shujinwangii comb. nov. (type strain XJ46^T = CGMCC 4.7125^T = JCM 19736^T).

Taxonomic note on the family Pseudonocardiaceae based on phylogenomic analysis and descriptions of Allosaccharopolyspora gen. nov. and Halosaccharopolyspora gen. nov

The taxonomic positions of members within the family Pseudonocardiaceae were assessed based on phylogenomic trees reconstructed using core-proteome and genome blast distance phylogeny approaches. The closely clustered genome sequences from the type strains of validly published names within the family Pseudonocardiaceae were analysed using overall genome-related indices based on average nucleotide identity, average amino acid identity and digital DNA-DNA hybridization values. The family Pseudonocardiaceae consists of the type genus Pseudonocardia, as well as the genera Actinoalloteichus, Actinocrispum, Actinokineospora, Actinomycetospora, Actinophytocola, Actinopolyspora, Actinorectispora, Actinosynnema, Allokutzneria, Allosaccharopolyspora gen. nov., Amycolatopsis, Bounagaea, Crossiella, Gandjariella, Goodfellowiella, Haloactinomyces, Haloechinothrix, Halopolyspora, Halosaccharopolyspora gen. nov., Herbihabitans, Kibdelosporangium, Kutzneria, Labedaea, Lentzea, Longimycelium, Prauserella, Saccharomonospora, Saccharopolyspora, Saccharothrix, Salinifilum, Sciscionella, Streptoalloteichus, Tamaricihabitans, Thermocrispum, Thermotunica and Umezawaea. The G+C contents of the Pseudonocardiaceae genomes ranged from 66.2 to 74.6 mol% and genome sizes ranged from 3.69 to 12.28 Mbp. Based on the results of phylogenomic analysis, the names Allosaccharopolyspora coralli comb. nov., Halosaccharopolyspora lacisalsi comb. nov. and Actinoalloteichus caeruleus comb. nov. are proposed. This study revealed that Actinokineospora mzabensis is a heterotypic synonym of Actinokineospora spheciospongiae, Lentzea deserti is a heterotypic synonym of Lentzea atacamensis, Prauserella endophytica is a heterotypic synonym of Prauserella coralliicola, and Prauserella flava and Prauserella sediminis are heterotypic synonyms of Prauserella salsuginis. This study addresses the nomenclature conundrums of Actinoalloteichus cyanogriseus and Streptomyces caeruleus as well as Micropolyspora internatus and Saccharomonospora viridis.

Lentzea tibetensis sp. nov., a novel Actinobacterium with antimicrobial activity isolated from soil of the Qinghai-Tibet Plateau

A novel filamentous Actinobacterium, designated strain FXJ1.1311^T, was isolated from soil collected in Ngari (Ali) Prefecture, Qinghai-Tibet Plateau, western PR China. The strain showed antimicrobial activity against Gram-positive bacteria and Fusarium oxysporum. Results of phylogenetic analysis based on 16S rRNA gene sequences indicated that strain FXJ1.1311^T belonged to the genus Lentzea and showed the highest sequence similarity to Lentzea guizhouensis DHS C013^T (98.04%). Morphological and chemotaxonomic characteristics supported its assignment to the genus Lentzea. The genome-wide average nucleotide identity between strain FXJ1.1311^T and L. guizhouensis DHS C013^T as well as other Lentzea type strains was <82.2 %. Strain FXJ1.1311^T also formed a monophyletic line distinct from the known Lentzea species in the phylogenomic tree. In addition, physiological and chemotaxonomic characteristics allowed phenotypic differentiation of the novel strain from L. guizhouensis. Based on the evidence presented here, strain FXJ1.1311^T represents a novel species of the genus Lentzea, for which the name Lentzea tibetensis sp. nov. is proposed. The type strain is FXJ1.1311^T (=CGMCC 4.7383^T=DSM 104975^T).

Lentzea alba sp. nov., a novel actinobacterium isolated from soil

A novel actinobacterium, designated strain NEAU-D13^T, was isolated from soil collected from Aohan Banner, Chifeng, Inner Mongolia Autonomous Region, China and characterized using a polyphasic approach. On the basis of 16S rRNA gene sequence analysis, strain NEAU-D13^T belonged to the genus Lentzea and shared the highest sequence similarity with Lentzea kentuckyensisJCM 14913^T (99.17 %). Morphological and chemotaxonomic characteristics of the strain also supported its assignment to the genus Lentzea. Cell walls contained meso-diaminopimelic acid as the diagnostic diamino acid and the whole-cell sugars were ribose and mannose. The phospholipid profile contained diphosphatidylglycerol, phosphatidylethanolamine, hydroxyphosphatidylethanolamine and phosphatidylinositol. The menaquinone was only MK-9(H₄). The major fatty acids were iso-C_16:0, C_16:0, anteiso-C_17:0, iso-C_15:0 and anteiso-C_15:0. DNA G+C content was 68.71 mol%. Phylogenetic analysis using the 16S rRNA gene sequences showed that the strain formed a stable clade with L. kentuckyensisJCM 14913^T in the genus Lentzea. Meanwhile, a combination of digital DNA-DNA hybridization results and some phenotypic characteristics demonstrated that strain NEAU-D13^T could be distinguished from its closely related strain. Therefore, it is concluded that strain NEAU-D13^T represents a novel species of the genus Lentzea, for which the name Lentzea alba sp. nov. is proposed, with NEAU-D13^T (=CCTCC AA 2019089^T=JCM 33970^T) as the type strain.

Lentzea indica sp. nov., a novel actinobacteria isolated from Indian Himalayan-soil

A novel actinobacterium, strain PSKA42^T was isolated from a soil sample of Kashmir Himalaya, India (latitude: 34°-01' N; longitude: 74°-47' E; altitude: 5328 ft). The morphological, biochemical and molecular characteristics predicted that PSKA42^T belongs to the genera Lentzea. Using the Ezbiocloud server it has also been manifested that the 16S rRNA gene sequence of PSKA42 was 98.4% similar with Lentzea guizhouensis DHSC013^T, Lentzea albidocapillata subsp. violacea IMSNU50388^T; 98.26% similar with Lentzea aerocolonigenes NRRLB-3298^T, Lentzea albidocapillata subsp. albidocapillata NRRLB-24057^T and 98.19% similar with Lentzea californiensis DSM43393^T. Whole-genome average nucleotide identity values between PSKA42^T and L. guizhouensis DHSC013^T, L. albidocapillata subsp. violaera IMSNU50388^T, L. aerocolonigenes NRRLB-3298^T, L. albidocapillata subsp. albidocapillata NRRLB-24057^T, L. californiensis DSM43393^T, L. flaviverucosa As40578^T were 84.94%, 85.8%, 87.15%, 87.71%, 79.29, and 87.22%, respectively, suggesting that PSKA42^T represented a new species. In-silco genome-to-genome distances analysis and MLSA with selected housekeeping genes also indicated that the isolate should be assigned to a new species under the genus Lentzea. Analysis of the whole-cell hydrolysate found mannose and ribose as major sugar while cell wall amino acid was identified as meso-diaminopimelic acid. Major fatty acids (> 5%) were observed as 15:0 iso (23.81%), and 16:0 iso (26.11%). PSKA42 contains polyketide synthase type-I genes but unable to show antimicrobial activity in laboratory conditions. The average GC content in its genome is 68.3%. Further, based on physicochemical, chemotaxonomic markers and molecular analysis, PSKA42^T can be assigned as novel species of Lentzea, we proposed Lentzea indica sp nov. The type strain is PSKA42^T (JCM 33729^T, MTCC 12936^T, MCC 4127^T).

Saccharothrix deserti sp. nov., an actinomycete isolated from desert soil

A Gram-stain-positive, aerobic actinomycete, designated strain BMP B8144^T, was isolated from desert soil, in Xinjiang province, northwest China. The isolate produced scanty aerial mycelium and fragmented substrate mycelium on most tested media. Cell-wall hydrolysates contained meso-diaminopimelic acid, galactose and mannose. The diagnostic phospholipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylhydroxylethanolamine, phosphatidylinositol, and phosphatidylinositol mannosides. The major fatty acids included iso-C_16 : 0, C_17 : 1 ω8c and iso-C_15 : 0. The predominant menaquinones were MK-9(H₄) and MK-10(H₄). The DNA G+C content was 70.4 mol% (genome). Based on the 16S rRNA gene sequence analysis on EzBioCloud server, strain BMP B8144^T showed the closest similarities to Saccharothrix lopnurensis YIM LPA2h^T (98.9 %) and 'Saccharothrix yanglingensis' Hhs.015 (98.6 %). However, it can be distinguished from the closest strains based on the low levels of DNA-DNA relatedness (59.3±1.8 and 47.9±2.3 %, respectively). A combination of morphological, chemotaxonomic and phylogenetic characteristics, strain BMP B8144^T represents a novel species of the genus Saccharothrix, for which the name Saccharothrix deserti sp. nov. is proposed. The type strain is BMP B8144^T (=CGMCC 4.7490^T=KCTC 49001^T).

Amycolatopsis nivea sp. nov., isolated from a Yellow River sample

A novel actinobacterium, designated strain CFH S0261^T, was isolated from a sediment sample of the Yellow River. The taxonomic position of the strain was investigated by using a polyphasic approach. Cells of strain CFH S0261^T were Gram-reaction-positive, aerobic, non-motile. Growth occurs at 15-37 °C, pH 6.0-8.0 and with 0-9.0 % (w/v) NaCl. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that strain CFH S0261^T was a member of the genus Amycolatopsis. The 16S rRNA gene sequence similarity indicated that strain CFH S0261^T is most closely related to the type strains of Amycolatopsis niigatensis LC11^T (98.95 %), Amycolatopsis echigonensis LC2^T (98.81 %) and Amycolatopsis albidoflavus IMSNU 22139^T (98.73 %). The whole-genome of CFH S0261^T showed a G+C content of 69.5 mol%. The ANI values and in silico DDH values between CFH S0261^T and the other species of the genus Amycolatopsis were found to be low (ANIb <90.61 % and DDH <53.40 %). The cell wall diamino acid in the peptidoglycan of strain CFH S0261^T was meso-diaminopimelic acid and the whole-cell hydrolysate comprised arabinose, galactose, glucose, rhamnose and ribose. The predominant menaquinone was MK-9(H₄). The major cellular fatty acids were C_16 : 0, iso-C_15 : 0 and iso-C_16 : 0. The polar lipid profile contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannosides and four unidentified glycolipids. On the basis of phenotypic, genotypic and phylogenetic data, strain CFH S0261^T represents a novel species of the genus Amycolatopsis, for which the name Amycolatopsis nivea sp. nov. is proposed. The type strain is CFH S0261^T (=KCTC 39515^T =CCTCC AA 2014028^T).

Amycolatopsis acidicola sp. nov., isolated from peat swamp forest soil

A novel actinobacterial strain, designated K81G1^T, was isolated from a soil sample collected in Kantulee peat swamp forest, Surat Thani Province, Thailand, and its taxonomic position was determined using a polyphasic approach. Optimal growth of strain K81G1^T occurred at 28-30 °C, at pH 5.0-6.0 and without NaCl. Strain K81G1^T had cell-wall chemotype IV (meso-diaminopimelic acid as the diagnostic diamino acid, and arabinose and galactose as diagnostic sugars) and phospholipid pattern type II, characteristic of the genus Amycolatopsis. It contained MK-9(H₄) as the predominant menaquinone, iso-C_16 : 0, C_17 : 0 cyclo and C_16 : 0 as the major cellular fatty acids, and phospholipids consisting of phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, hydroxyphosphatidylethanolamine, phosphatidylinositol and two unidentified phospholipids. Based on 16S rRNA gene sequence similarity and phylogenetic analyses, strain K81G1^T was most closely related to Amycolatopsis rhizosphaerae TBRC 6029^T (97.8 % similarity), Amycolatopsis acidiphila JCM 30562^T (97.8 %) and Amycolatopsis bartoniae DSM 45807^T (97.6 %). Strain K81G1^T exhibited low average nucleotide identity and digital DNA-DNA hybridization values with A. rhizosphaerae TBRC 6029^T (76.4 %, 23.0 %), A. acidiphila JCM 30562^T (77.9 %, 24.6 %) and A. bartoniae DSM 45807^T (77.8 %, 24.3 %). The DNA G+C content of strain K81G1^T was 69.7 mol%. Based on data from this polyphasic study, strain K81G1^T represents a novel species of the genus Amycolatopsis, for which the name Amycolatopsis acidicola sp. nov. is proposed. The type strain is K81G1^T (=TBRC 10047^T=NBRC 113896^T).

Lentzea terrae sp. nov., isolated from soil and an emended description of Lentzea soli

A novel actinobacterium, designated strain NEAU-LZS 42^T, was isolated from soil collected from Mount Song, Henan Province, China, and characterized using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the organism should be assigned to the genus Lentzea and had the closest relationship with Lentzea soli NEAU-LZC 7^T (99.1 % similarity) and Lentzea cavernae SYSU K10001^T (98.2 %). The major menaquinones were identified as MK-9(H4) and MK-9(H2). The phospholipid profile was found to contain diphosphatidylglycerol, phosphatidylethanolamine, hydroxy-phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside, glycophospholipid and three unidentified lipids. The major fatty acids were iso-C16 : 0, C16 : 1ω7c and C16 : 0. DNA-DNA hybridization results and some phenotypic characteristics indicated that strain NEAU-LZS 42^T could be clearly differentiated from L. soli NEAU-LZC 7^T and L. cavernae SYSU K10001^T. Therefore, it is concluded that strain NEAU-LZS 42^T represents a novel species of the genus Lentzea, for which the name Lentzea terrae sp. nov. is proposed. The type stain is NEAU-LZS 42^T (=CGMCC 4.7428^T=DSM 105696^T).

Genome-Based Taxonomic Classification of the Phylum Actinobacteria

The application of phylogenetic taxonomic procedures led to improvements in the classification of bacteria assigned to the phylum Actinobacteria but even so there remains a need to further clarify relationships within a taxon that encompasses organisms of agricultural, biotechnological, clinical, and ecological importance. Classification of the morphologically diverse bacteria belonging to this large phylum based on a limited number of features has proved to be difficult, not least when taxonomic decisions rested heavily on interpretation of poorly resolved 16S rRNA gene trees. Here, draft genome sequences of a large collection of actinobacterial type strains were used to infer phylogenetic trees from genome-scale data using principles drawn from phylogenetic systematics. The majority of taxa were found to be monophyletic but several orders, families, and genera, as well as many species and a few subspecies were shown to be in need of revision leading to proposals for the recognition of 2 orders, 10 families, and 17 genera, as well as the transfer of over 100 species to other genera. In addition, emended descriptions are given for many species mainly involving the addition of data on genome size and DNA G+C content, the former can be considered to be a valuable taxonomic marker in actinobacterial systematics. Many of the incongruities detected when the results of the present study were compared with existing classifications had been recognized from 16S rRNA gene trees though whole-genome phylogenies proved to be much better resolved. The few significant incongruities found between 16S/23S rRNA and whole genome trees underline the pitfalls inherent in phylogenies based upon single gene sequences. Similarly good congruence was found between the discontinuous distribution of phenotypic properties and taxa delineated in the phylogenetic trees though diverse non-monophyletic taxa appeared to be based on the use of plesiomorphic character states as diagnostic features.

Pseudonocardia mangrovi sp. nov., isolated from soil

A novel Gram-stain-positive, aerobic actinomycete, designated strain SMC 195^T, was isolated from soil collected from a mangrove forest in Thailand. The strain produced extensively branched substrate and aerial mycelia. The substrate mycelium was fragmented into rod-shaped elements, and spore chains consisting of smooth and rod-shaped spores were formed on the aerial mycelium. The results of phylogenetic analysis based on 16S rRNA gene sequences indicated that SMC 195^T represented a member of the genus Pseudonocardia, and the most closely phylogenetically related species were Pseudonocardia yuanmonensisJCM 18055^T (99.2 % 16S rRNA gene sequence similarity), Pseudonocardia halophobicaNRRL B-16514^T (98.9 %) and Pseudonocardia kujensisNRRL B-24890^T (98.7 %). However, the DNA-DNA relatedness values between SMC 195^Tand the closest phylogenetically related species were significantly below 70 %. The G+C content of the genomic DNA was 74±0.8 mol%. The cell wall peptidoglycan contained meso-diaminopimelic acid. The whole-cell sugars consisted of arabinose, galactose, glucose, rhamnose and ribose. The menaquinone was MK-8(H4) only. The major cellular fatty acid was the branched fatty acid iso-C16 : 0 (33.6 %). The polar lipids detected were phosphatidylethanolamine, phosphatidylmethylethanolamine, hydroxyphosphatidylethanolamine, diphosphatidylglycerol, phosphatidylinositol and unidentified glycolipids. On the basis of the results from phenotypic, chemotaxonomic and genotypic studies, it is concluded that SMC 195^T represents a novel species of the genus Pseudonocardia, for which the name Pseudonocardia mangrovi sp. nov. is proposed. The type strain is SMC 195^T (=TBRC 7778^T=NBRC 113150^T).

Amycolatopsis antarctica sp. nov., isolated from the surface of an Antarctic brown macroalga

Two moderately psychrophilic actinobacterial strains, designated AU-G6T and AU-A3.2, isolated from the surface of an Antarctic macroalga, Adenocystis utricularis (Bory) Skottsberg, was taxonomically characterized based on a polyphasic investigation. The two strains had nearly identical 16S rRNA gene sequences and formed a distinct phyletic line within the genus Amycolatopsis of the family Pseudonocardiaceae. They were phylogenetically close to Amycolatopsis nigrescens JCM 14717T, Amycolatopsis minnesotensis JCM 14545T and Amycolatopsis magusensis DSM 45510T, with 16S rRNA gene sequence similarities of 97.77, 97.20 and 97.19 %, respectively. Phylogenomic analysis based on the whole genome data supported that strain AU-G6T was distantly related to the Amycolatopsis species. The isolates shared a range of phenotypic markers typical of members of the genus Amycolatopsis, but also had a range of cultural, physiological and biochemical characteristics that separated them from related Amycolatopsis species. The isolates showed growth only in media supplemented with salt, indicating their marine origin. The cell wall of the isolates contained meso-diaminopimelic acid, and arabinose and galactose were detected as diagnostic sugars (type IV). The main menaquinone was MK-9(H4). The main polar lipids were phosphatidylethanolamine, hydroxy-phosphotidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol and phosphatidylinositol (type II). The fatty acid type was 3c. The combined genotypic and phenotypic data indicated that the two isolates represent a novel species of the genus Amycolatopsis. The name proposed for this species is Amycolatopsis antarctica sp. nov., with type strain AU-G6T (=CGMCC 4.7351T=NBRC 112404T).

Actinophytocola glycyrrhizae sp. nov. isolated from the rhizosphere of Glycyrrhiza inflata

A Gram-stain-positive, aerobic actinomycete, designated strain BMP B8152^T, was isolated from the rhizosphere of Glycyrrhiza inflata collected ashore, in Kashi, Xinjiang province, northwest PR China. A polyphasic approach was used to establish the taxonomic position of this strain. BMP B8152^T was observed to form non-fragmented substrate mycelium, and relatively scanty aerial mycelium with rod-shaped spores. Cell-wall hydrolysates contained meso-diaminopimelic acid, galactose, arabinose, glucose and rhamnose (trace). Mycolic acids were not detected. The diagnostic phospholipids were identified as diphosphatidylglycerol, phosphatidylethanolamine, hydroxyphosphatidylethanolamine, ninhydrin-positive phosphoglycolipid and phosphatidylinositol. The predominant menaquinone and fatty acid were MK-9(H4) and iso-branched hexadecanoate (iso-C16 : 0), respectively. The phylogenetic analyses based on the 16S rRNA gene sequences indicated that BMP B8152^T formed a distinct monophyletic clade clustered with Actinophytocola timorensisID05-A0653^T (98.8 % 16S rRNA gene sequence similarity), Actinophytocola oryzaeGMKU 367^T (98.6 %), Actinophytocola corallinaID06-A0464^T (98.2 %) and Actinophytocola burenkhanensisMN08-A0203^T (97.5 %). In addition, DNA-DNA hybridization values between BMP B8152^T and A. timorensisID05-A0653^T(44.2±3.6 %) and A. oryzaeGMKU 367^T(36.7±2.3 %) were well below the 70 % limit for species identification. The combined phenotypic and genotypic data indicate that the isolate represents a novel species of the genus Actinophytocola, for which the name Actinophytocola glycyrrhizae sp. nov., is proposed, with the type strain BMP B8152^T (=KCTC 49002^T=CGMCC 4.7433^T).

Lentzea soli sp. nov., an actinomycete isolated from soil

A novel actinobacterium, designated strain NEAU-LZC 7^T, was isolated from soil collected from Mount Song and characterized using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequence indicated that strain NEAU-LZC 7^T belonged to the genus Lentzea, with highest sequence similarity to Lentzea violacea JCM 10975^T (98.1 %). Morphological and chemotaxonomic characteristics of the strain also supported its assignment to the genus Lentzea. However, DNA-DNA relatedness, physiological and biochemical data showed that strain NEAU-LZC 7^T could be distinguished from its closest relative. Therefore, strain NEAU-LZC 7^T represents a novel species of the genus Lentzea, for which the name Lentzea soli sp. nov. is proposed, with NEAU-LZC 7^T (=CCTCC AA 2017027^T=JCM 32384^T) as the type strain.

Lechevalieria rhizosphaerae sp. nov., a novel actinomycete isolated from rhizosphere soil of wheat (Triticum aestivum L.) and emended description of the genus Lechevalieria

A novel actinomycete, designated strain NEAU-A2^T, was isolated from rhizosphere soil of wheat (Triticum aestivum L.) and characterized using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain NEAU-A2^T should be assigned to the genus Lechevalieria and forms a distinct branch with its closest neighbour Lechevalieria aerocolonigenes DSM 40034^T (99.0 %). Moreover, key morphological and chemotaxonomic properties also confirmed the affiliation of strain NEAU-A2^T to the genus Lechevalieria. The cell wall contained meso-diaminopimelic acid and the whole-cell hydrolysates were galactose, mannose, rhamnose, glucose and ribose. The polar lipids were diphosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylethanolamine, phosphatidylinositolmannoside and two glycolipids. The predominant menaquinones were MK-9(H4) and MK-9(H6). The major fatty acids were iso-C16 : 0, anteiso-C15 : 0, C16 : 1ω7c and anteiso-C17 : 0. The DNA G+C content was 68.2 mol%. The combination of the DNA-DNA hybridization result and some phenotypic characteristics demonstrated that strain NEAU-A2^T could be distinguished from its closest relative. Therefore, it is proposed that strain NEAU-A2^T represents a novel species of the genus Lechevalieria, for which the name Lechevalieriarhizosphaerae sp. nov. is proposed. The type strain is NEAU-A2^T (=CGMCC 4.7405^T=DSM 104541^T).

Actinoalloteichus fjordicus sp. nov. isolated from marine sponges: phenotypic, chemotaxonomic and genomic characterisation

Two actinobacterial strains, ADI 127-17^T and GBA 129-24, isolated from marine sponges Antho dichotoma and Geodia barretti, respectively, collected at the Trondheim fjord in Norway, were the subjects of a polyphasic study. According to their 16S rRNA gene sequences, the new isolates were preliminarily classified as belonging to the genus Actinoalloteichus. Both strains formed a distinct branch, closely related to the type strains of Actinoalloteichus hoggarensis and Actinoalloteichus hymeniacidonis, within the evolutionary radiation of the genus Actinoalloteichus in the 16S rRNA gene-based phylogenetic tree. Isolates ADI 127-17^T and GBA 129-24 exhibited morphological, chemotaxonomic and genotypic features distinguishable from their close phylogenetic neighbours. Digital DNA: DNA hybridization and ANI values between strains ADI 127-17^T and GBA 129-24 were 97.6 and 99.7%, respectively, whereas the corresponding values between both tested strains and type strains of their closely related phylogenetic neighbours, A. hoggarensis and A. hymeniacidonis, were well below the threshold for delineation of prokaryotic species. Therefore, strains ADI 127-17^T (= DSM 46855^T) and GBA 129-24 (= DSM 46856) are concluded to represent a novel species of the genus Actinoalloteichus for which the name of Actinoalloteichus fjordicus sp. nov. (type strain ADI 127-17^T = DSM 46855^T = CECT 9355^T) is proposed. The complete genome sequences of the new strains were obtained and compared to that of A. hymeniacidonis DSM 45092^T and A. hoggarensis DSM 45943^T to unravel unique genome features and biosynthetic potential of the new isolates.

Lentzea cavernae sp. nov., an actinobacterium isolated from a karst cave sample, and emended description of the genus Lentzea

A novel actinobacterial strain, designated SYSU K10001T, was isolated from a limestone sample collected from a karst cave in Xingyi county, Guizhou province, south-western China. The taxonomic position of the strain was investigated using a polyphasic approach. Cells of the strain were aerobic and Gram-stain-positive. On the basis of 16S rRNA gene sequence analysis, strain SYSU K10001T was most closely related to the type strains of the genus Lentzea, Lentzea albida NBRC 16102T (98.8 % similarity) and Lentzea waywayandensis NRRL B-16159T (98.6 %), and is therefore considered to represent a member of the genus Lentzea. DNA-DNA hybridization values between strain SYSU K10001T and related type strains of the genus Lentzea were less than 70 %. In addition, meso-diaminopimelic acid was the diagnostic diamino acid in the cell-wall peptidoglycan. The whole-cell sugars were arabinose, fructose, mannose and xylose. The major isoprenoid quinone was MK-9(H4), while the major fatty acids (>10 %) were iso-C16 : 0 and C14 : 0. The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, hydroxy-phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside, one unidentified phospholipid and one unidentified lipid. The genomic DNA G+C content of strain SYSU K10001T was 69.4 mol%. On the basis of phenotypic, genotypic and phylogenetic data, strain SYSU K10001T represents a novel species of the genus Lentzea, for which the name Lentzea cavernae sp. nov. is proposed. The type strain is SYSU K10001T (=KCTC 39804T=CGMCC 4.7367T=NBRC 112394T).

Polysaccharide Degradation Capability of Actinomycetales Soil Isolates from a Semiarid Grassland of the Colorado Plateau

Among the bacteria, members of the order Actinomycetales are considered quintessential degraders of complex polysaccharides in soils. However, studies examining complex polysaccharide degradation by Actinomycetales (other than Streptomyces spp.) in soils are limited. Here, we examine the lignocellulolytic and chitinolytic potential of 112 Actinomycetales strains, encompassing 13 families, isolated from a semiarid grassland of the Colorado Plateau in Utah. Members of the Streptomycetaceae, Pseudonocardiaceae, Micromonosporaceae, and Promicromonosporaceae families exhibited robust activity against carboxymethyl cellulose, xylan, chitin, and pectin substrates (except for low/no pectinase activity by the Micromonosporaceae). When incubated in a hydrated mixture of blended Stipa and Hilaria grass biomass over a 5-week period, Streptomyces and Saccharothrix (a member of the Pseudonocardiaceae) isolates produced high levels of extracellular enzyme activity, such as endo- and exocellulase, glucosidase, endo- and exoxylosidase, and arabinofuranosidase. These characteristics make them well suited to degrade the cellulose and hemicellulose components of grass cell walls. On the basis of the polysaccharide degradation profiles of the isolates, relative abundance of Actinomycetales sequences in 16S rRNA gene surveys of Colorado Plateau soils, and analysis of genes coding for polysaccharide-degrading enzymes among 237 Actinomycetales genomes in the CAZy database and 5 genomes from our isolates, we posit that Streptomyces spp. and select members of the Pseudonocardiaceae and Micromonosporaceae likely play an important role in the degradation of hemicellulose, cellulose, and chitin substances in dryland soils.IMPORTANCE Shifts in the relative abundance of Actinomycetales taxa have been observed in soil microbial community surveys during large, manipulated climate change field studies. However, our limited understanding of the ecophysiology of diverse Actinomycetales taxa in soil systems undermines attempts to determine the underlying causes of the population shifts or their impact on carbon cycling in soil. This study combines a systematic analysis of the polysaccharide degradation potential of a diverse collection of Actinomycetales isolates from surface soils of a semiarid grassland with analysis of genomes from five of these isolates and publicly available Actinomycetales genomes for genes encoding polysaccharide-active enzymes. The results address an important gap in knowledge of Actinomycetales ecophysiology-identification of key taxa capable of facilitating lignocellulose degradation in dryland soils. Information from this study will benefit future metagenomic studies related to carbon cycling in dryland soils by providing a baseline linkage of Actinomycetales phylogeny with lignocellulolytic functional potential.

Complete genome sequence of the actinomycete Actinoalloteichus hymeniacidonis type strain HPA 177T isolated from a marine sponge

Actinoalloteichus hymeniacidonis HPA 177T is a Gram-positive, strictly aerobic, black pigment producing and spore-forming actinomycete, which forms branching vegetative hyphae and was isolated from the marine sponge Hymeniacidon perlevis. Actinomycete bacteria are prolific producers of secondary metabolites, some of which have been developed into anti-microbial, anti-tumor and immunosuppressive drugs currently used in human therapy. Considering this and the growing interest in natural products as sources of new drugs, actinomycete bacteria from the hitherto poorly explored marine environments may represent promising sources for drug discovery. As A. hymeniacidonis, isolated from the marine sponge, is a type strain of the recently described and rare genus Actinoalloteichus, knowledge of the complete genome sequence enables genome analyses to identify genetic loci for novel bioactive compounds. This project, describing the 6.31 Mbp long chromosome, with its 5346 protein-coding and 73 RNA genes, will aid the Genomic Encyclopedia of Bacteria and Archaea project.

Saccharothrix ghardaiensis sp. nov., an actinobacterium isolated from Saharan soil

The taxonomic position of a new Saccharothrix strain, designated MB46^T, isolated from a Saharan soil sample collected in Mzab region (Ghardaïa province, South Algeria) was established following a polyphasic approach. The novel microorganism has morphological and chemical characteristics typical of the members of the genus Saccharothrix and formed a phyletic line at the periphery of the Saccharothrix espanaensis subcluster in the 16S rRNA gene dendrograms. Results of the 16S rRNA gene sequence comparisons revealed that strain MB46^T shares high degrees of similarity with S. espanaensis DSM 44229^T (99.2%), Saccharothrix variisporea DSM 43911^T (98.7%) and Saccharothrix texasensis NRRL B-16134^T (98.6%). However, the new strain exhibited only 12.5-17.5% DNA relatedness to the neighbouring Saccharothrix spp. On the basis of phenotypic characteristics, 16S rRNA gene sequence comparisons and DNA-DNA hybridizations, strain MB46^T is concluded to represent a novel species of the genus Saccharothrix, for which the name Saccharothrix ghardaiensis sp. nov. (type strain MB46^T = DSM 46886^T = CECT 9046^T) is proposed.

A systematic study of the whole genome sequence of Amycolatopsis methanolica strain 239T provides an insight into its physiological and taxonomic properties which correlate with its position in the genus

The complete genome of methanol-utilizing Amycolatopsis methanolica strain 239^T was generated, revealing a single 7,237,391 nucleotide circular chromosome with 7074 annotated protein-coding sequences (CDSs). Comparative analyses against the complete genome sequences of Amycolatopsis japonica strain MG417-CF17^T, Amycolatopsis mediterranei strain U32 and Amycolatopsis orientalis strain HCCB10007 revealed a broad spectrum of genomic structures, including various genome sizes, core/quasi-core/non-core configurations and different kinds of episomes. Although polyketide synthase gene clusters were absent from the A. methanolica genome, 12 gene clusters related to the biosynthesis of other specialized (secondary) metabolites were identified. Complete pathways attributable to the facultative methylotrophic physiology of A. methanolica strain 239^T, including both the mdo/mscR encoded methanol oxidation and the hps/hpi encoded formaldehyde assimilation via the ribulose monophosphate cycle, were identified together with evidence that the latter might be the result of horizontal gene transfer. Phylogenetic analyses based on 16S rDNA or orthologues of AMETH_3452, a novel actinobacterial class-specific conserved gene against 62 or 18 Amycolatopsis type strains, respectively, revealed three major phyletic lineages, namely the mesophilic or moderately thermophilic A. orientalis subclade (AOS), the mesophilic Amycolatopsis taiwanensis subclade (ATS) and the thermophilic A. methanolica subclade (AMS). The distinct growth temperatures of members of the subclades correlated with corresponding genetic variations in their encoded compatible solutes. This study shows the value of integrating conventional taxonomic with whole genome sequence data.

Saccharothrix isguenensis sp. nov., an actinobacterium isolated from desert soil

A novel actinobacterial strain, designated MB27T, was isolated from a Saharan soil sample collected in Mzab region (Ghardaïa province, South Algeria). Strain MB27T was characterized following a polyphasic taxonomic approach. This strain produced a branched and fragmented substrate mycelium, which was found to have a yellowish orange colour. A white scanty aerial mycelium was produced on most media tested. Chemotaxonomic and phylogenetic studies clearly demonstrated that strain MB27T belongs to the family Pseudonocardiaceae and is closely related to the genus Saccharothrix. Cell-wall hydrolysates contained meso-diaminopimelic acid but not glycine, and whole-cell hydrolysates contained galactose, glucose, ribose and small amounts of mannose and rhamnose. The detected phospholipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylethanolamine, phosphatidylinositol and phosphatidylinositol mannosides. Mycolic acids were not detected while the predominant fatty acid was iso-branched hexadecanoate (iso-C16 : 0). The major menaquinone was MK-9(H4). Results of 16S rRNA gene sequence comparisons revealed that strain MB27T shairs the highest degree of similarity with Saccharothrix ecbatanensis DSM 45486T (99.8%), Saccharothrix hoggarensis DSM 45457T (99.3 %), Saccharothrix longispora DSM 43749T (98.6 %) and Saccharothrix yanglingensis DSM 45665T (98.6 %). However, it exhibited only 11-42 % DNA-DNA relatedness to the neighbouring Saccharothrixspecies. On the basis of phenotypic characteristics, 16S rRNA gene sequence comparisons and DNA-DNA hybridization, strain MB27T is shown to represent a novel species of the genus Saccharothrix, for which the name Saccharothrix isguenensis sp. nov. (type strain MB27T=DSM 46885T=CECT 9045T) is proposed.

Herbihabitans rhizosphaerae gen. nov., sp. nov., a member of the family Pseudonocardiaceae isolated from rhizosphere soil of the herb Limonium sinense (Girard)

The taxonomic position of an actinobacterium, designated CPCC 204279T, which was isolated from a rhizosphere soil sample of the herb Limonium sinense collected from Xinjiang Province, China, was established using a polyphasic approach. Whole-cell hydrolysates of strain CPCC 204279T contained galactose and arabinose as diagnostic sugars and meso-diaminopimelic acid as the diamino acid. The muramic acid residues in the peptidoglycan were N-acetylated. The predominant menaquinone was MK-9(H4). The phospholipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol and phosphatidylinositol mannosides. The major fatty acids were iso-C16 : 0, iso-C16 : 0 2-OH, C16 : 1ω9c, iso-C16 : 1 and C16 : 0. The genomic DNA G+C content was 73.2 mol%. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain CPCC 204279T should be placed in the family Pseudonocardiaceae, in which the strain formed a distinct lineage next to the genus Actinophytocola. Signature nucleotides in the 16S rRNA gene sequence showed that the strain contained the Pseudonocardiaceae family-specific 16S rRNA signature nucleotides and a genus-specific diagnostic nucleotide signature pattern. The combination of phylogenetic analysis and phenotypic characteristics supported the conclusion that strain CPCC 204279T represents a novel species of a new genus in the family Pseudonocardiaceae, for which the name Herbihabitans rhizosphaerae gen. nov., sp. nov. is proposed. Strain CPCC 204279T (=NBRC 111774T=DSM 101727T) is the type strain of the type species.

Classification of thermophilic actinobacteria isolated from arid desert soils, including the description of Amycolatopsis deserti sp. nov

The taxonomic position of 26 filamentous actinobacteria isolated from a hyper-arid Atacama Desert soil and 2 from an arid Australian composite soil was established using a polyphasic approach. All of the isolates gave the diagnostic amplification product using 16S rRNA oligonucleotide primers specific for the genus Amycolatopsis. Representative isolates had chemotaxonomic and morphological properties typical of members of the genus Amycolatopsis. 16S rRNA gene analyses showed that all of the isolates belong to the Amycolatopsis methanolica 16S rRNA gene clade. The Atacama Desert isolates were assigned to one or other of two recognised species, namely Amycolatopsis ruanii and Amycolatopsis thermalba, based on 16S rRNA gene sequence, DNA:DNA relatedness and phenotypic data; emended descriptions are given for these species. In contrast, the two strains from the arid Australian composite soil, isolates GY024(T) and GY142, formed a distinct branch at the periphery of the A. methanolica 16S rRNA phyletic line, a taxon that was supported by all of the tree-making algorithms and by a 100 % bootstrap value. These strains shared a high degree of DNA:DNA relatedness and have many phenotypic properties in common, some of which distinguished them from all of the constituent species classified in the A. methanolica 16S rRNA clade. Isolates GY024(T) and GY142 merit recognition as a new species within the A. methanolica group of thermophilic strains. The name proposed for the new species is Amycolatopsis deserti sp. nov.; the type strain is GY024(T) (=NCIMB 14972(T) = NRRL B-65266(T)).

Actinorectispora indica gen. nov., sp. nov. isolated from soil, a member of the family Pseudonocardiaceae

The taxonomic positions of three Gram-stain-positive, aerobic strains, designated YIM 75722, 75726 and 75728^T, and isolated from a soil sample collected from Kurnool of Andhra Pradesh province, India, were assessed using a polyphasic approach. Growth was observed at pH 7.0-10.0 (optimum pH 7.0), 15-28 °C (optimum 28 °C) and 0-8 % (w/v) NaCl (grew without NaCl). Strains showed cylindrical spores with straight-chain morphology on aerial mycelium, but did not reveal sporangium-like structures or fragmentation of the substrate mycelium. Whole-cell hydrolysates of all strains contained galactose and ribose as the diagnostic sugars and meso-diaminopimelic acid as the diamino acid. The predominant menaquinone was MK-9(H₄); MK-9 (H₆) and MK-10 (H₄) were present in smaller amounts. The phospholipid pattern consisted mainly of diphosphatidylglycerol, phosphatidylglycerol and phosphatidylcholine. The major fatty acids were i-C_15 : 0, ai-C_15 : 0, i-C_17 : 0 and ai-C_17 : 0. The genomic DNA G+C content was 68.0 mol%. Phylogenetic analysis, based on 16S rRNA gene sequences, revealed that strain YIM 75728^T should be placed within the family Pseudonocardiaceae, in which the strain formed a distinct lineage. The combination of phylogenetic analysis, phenotypic characteristics and chemotaxonomic data support the conclusion that strain YIM 75728^T represents a novel species of a novel genus of the family Pseudonocardiaceae for which the name Actinorectispora indica gen. nov., sp. nov., is proposed. Strain YIM 75728^T ( = DSM 45410^T = CCTCC AA 209065^T) is the type strain of Actinorectispora indica. Strain YIM 75728^T was considered as the type strain over the other two strains based on the highest sequence read length of the strain.

Tamaricihabitans halophyticus gen. nov., sp. nov., an endophytic actinomycete of the family Pseudonocardiaceae

A novel actinomycete strain, designated KLBMP 1356T, was isolated from the root of halophyte Tamarix chinensis Lour. collected from the coastal area of Jiangsu province, PR China. The isolate was characterized using a polyphasic approach. Comparative analysis of the 16S rRNA gene sequence indicated that strain KLBMP 1356T was phylogenetically related to members of the family Pseudonocardiaceae and formed a distinct monophyletic clade between the genera Amycolatopsis (93.1–94.7 % 16S rRNA gene sequence similarity), Prauserella (93.6–95.1 %) and Saccharomonospora (93.2–94.3 %). The isolate displayed long spore chains containing rod-shaped and smooth-surfaced spores. Strain KLBMP 1356T contained meso-diaminopimelic acid as the diagnostic diamino acid, and galactose, arabinose and glucose as the whole-cell sugars. The major menaquinone was MK-9(H4) and the fatty acid profile was characterized by the predominance of iso-C16 : 0, C17 : 1ω8c, C17 : 1ω6c and C17 : 0. The polar lipids comprised diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, unknown aminophospholipids and an unknown glycolipid. Mycolic acids were not present. The G+C content of the genomic DNA was 67.2 mol%. On the basis of the evidence from this polyphasic study, strain KLBMP 1356T is considered to represent a novel species of a new genus in the family Pseudonocardiaceae, for which the name Tamaricihabitans halophyticus gen. nov., sp. nov. is proposed. The type strain of the type species is KLBMP 1356T ( = DSM 45765T = NBRC 109361T).

Lentzea guizhouensis sp. nov., a novel lithophilous actinobacterium isolated from limestone from the Karst area, Guizhou, China

A novel filamentous actinobacterium, designated strain DHS C013(T), was isolated from limestone collected in Guizhou Province, South-west China. Morphological and chemotaxonomic characteristics of the strain support its assignment to the genus Lentzea. Phylogenetic analyses showed that strain DHS C013(T) is closely related to Lentzea jiangxiensis FXJ1.034(T) (98.7 % 16S rRNA gene similarity) and Lentzea flaviverrucosa 4.0578(T) (98.0 % 16S rRNA gene similarity), but it can be distinguished from these strains based on low levels of DNA:DNA relatedness (~44 and ~37 %, respectively). Physiological and biochemical tests also allowed phenotypic differentiation of the novel strain from these closely related species. On the basis of the evidence presented here, strain DHS C013(T) is concluded to represent a novel species of the genus Lentzea, for which the name Lentzea guizhouensis sp. nov. is proposed. The type strain is DHS C013(T) (=KCTC 29677(T) = CGMCC 4.7203(T)).

Thermotunica guangxiensis gen. nov., sp. nov., isolated from mushroom residue compost

A novel thermophilic actinomycete, designated AG2-7T, was isolated from mushroom residue compost in Guangxi University, Nanning, China. The strain grew optimally at 45–60 °C, at pH 7.0 and with 0–3.0 % (w/v) NaCl. Vegetative mycelia were branched and whitish to pale yellow without fragmentation. Aerial mycelium was abundant, whitish and differentiated into long chains of spores, with a membranous structure or tunica partially covering the surface of aerial hyphae. The non-motile spores were oval in shape with a ridged surface. Strain AG-27T contained meso-diaminopimelic acid as the diagnostic diamino acid, and the whole-cell sugars were galactose and ribose. Major fatty acids were iso-C16 : 0 (27.51 %), iso-C17 : 0 (10.47 %) and anteiso-C17 : 0 (12.01 %). MK-9(H4) was the predominant menaquinone. The polar phospholipids were diphosphatidylglycerol, ninhydrin-positive glycophospholipid, phosphatidylinositol, phosphatidylinositol mannoside, phosphatidylethanolamine, phosphatidylmethylethanolamine, an unknown phospholipid and unknown glucosamine-containing phospholipids. The G+C content of the genomic DNA was 63.6 mol%. 16S rRNA gene sequence analysis showed that the organism belonged to the family Pseudonocardiaceae , suborder Pseudonocardineae and showed more than 5 % divergence from other members of the family. Based on the phenotypic and phylogenetic data, strain AG2-7T represents a novel species of a new genus in the family Pseudonocardiaceae , for which the name Thermotunica guangxiensis gen. nov., sp. nov. is proposed. The type strain of the type species is AG2-7T ( = ATCC BAA-2499T = CGMCC 4.7099T).

Pseudonocardia cypriaca sp. nov., Pseudonocardia salamisensis sp. nov., Pseudonocardia hierapolitana sp. nov. and Pseudonocardia kujensis sp. nov., isolated from soil

The taxonomic positions of four novel actinomycetes isolated from soil samples, designated KT2142T, PM2084T, K236T and A4038T, were established by using a polyphasic approach. The organisms had chemical and morphological features that were consistent with their classification in the genus Pseudonocardia. Whole-cell hydrolysates of the four strains contained meso-diaminopimelic acid and arabinose and galactose as the diagnostic sugars (cell-wall type IV). Their predominant menaquinone was found to be MK-8(H4). The major fatty acid was iso-C16:0. 16S rRNA gene sequence data supported the classification of the isolates in the genus Pseudonocardia and showed that they formed four distinct branches within the genus. DNA-DNA relatedness studies between the isolates and their phylogenetic neighbours showed that they belonged to distinct genomic species. The four isolates were readily distinguished from one another and from the type strains of species classified in the genus Pseudonocardia based on a combination of phenotypic and genotypic properties. In conclusion, it is proposed that the four isolates be classified in four novel species of the genus Pseudonocardia, for which the names Pseudonocardia cypriaca sp. nov. (type strain KT2142T=KCTC 29067T=DSM 45511T=NRRL B-24882T), Pseudonocardia hierapolitana sp. nov. (type strain PM2084T=KCTC 29068T=DSM 45671T=NRRL B-24879T), Pseudonocardia salamisensis sp. nov. (type strain K236T=KCTC 29100T=DSM 45717T) and Pseudonocardia kujensis sp. nov. (type strain A4038T=KCTC 29062T=DSM 45670T=NRRL B-24890T) are proposed.

Genome sequence of the chemoheterotrophic soil bacterium Saccharomonospora cyanea type strain (NA-134(T))

Saccharomonospora cyanea Runmao et al. 1988 is a member of the genus Saccharomonospora in the family Pseudonocardiaceae that is moderately well characterized at the genome level thus far. Members of the genus Saccharomonospora are of interest because they originate from diverse habitats, such as soil, leaf litter, manure, compost, surface of peat, moist, over-heated grain, and ocean sediment, where they probably play a role in the primary degradation of plant material by attacking hemicellulose. Species of the genus Saccharomonospora are usually Gram-positive, non-acid fast, and are classified among the actinomycetes. S. cyanea is characterized by a dark blue (= cyan blue) aerial mycelium. After S. viridis, S. azurea, and S. marina, S. cyanea is only the fourth member in the genus for which a completely sequenced (non-contiguous finished draft status) type strain genome will be published. Here we describe the features of this organism, together with the draft genome sequence, and annotation. The 5,408,301 bp long chromosome with its 5,139 protein-coding and 57 RNA genes was sequenced as part of the DOE funded Community Sequencing Program (CSP) 2010 at the Joint Genome Institute (JGI).

Longimycelium tulufanense gen. nov., sp. nov., a filamentous actinomycete of the family Pseudonocardiaceae

A novel filamentous actinomycete strain, designated TRM 46004T, was isolated from sediment of Aiding Lake in Tulufan Basin (42° 64′ N 89° 26′ E), north-west China. The isolate was characterized using a polyphasic approach. The isolate formed abundant aerial mycelium with few branches and vegetative mycelium, occasionally twisted and coiled; spherical sporangia containing one to several spherical spores developed at the ends of short sporangiophores on aerial mycelium. The G+C content of the DNA was 65.2 mol%. The isolate contained meso-diaminopimelic acid as the diagnostic diamino acid and xylose, galactose and ribose as the major whole-cell sugars. The diagnostic phospholipids were phosphatidylethanolamine, phosphatidylcholine and phosphatidylglycerol. The predominant menaquinones were MK-9(H4), MK-9(H6) and MK-9(H10). The major fatty acids were iso-C16 : 0 and anteiso-C17 : 0. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain TRM 46004T formed a distinct lineage within the family Pseudonocardiaceae and showed 91.7–96.1 % 16S rRNA gene sequence similarity with members of the family Pseudonocardiaceae . On the basis of the evidence from this polyphasic study, a novel genus and species, Longimycelium tulufanense gen. nov., sp. nov., are proposed. The type strain of Longimycelium tulufanense is TRM 46004T ( = CGMCC 4.5737T = NBRC 107726T).

Complete genome sequence of Saccharothrix espanaensis DSM 44229(T) and comparison to the other completely sequenced Pseudonocardiaceae

Background

The genus Saccharothrix is a representative of the family Pseudonocardiaceae, known to include producer strains of a wide variety of potent antibiotics. Saccharothrix espanaensis produces both saccharomicins A and B of the promising new class of heptadecaglycoside antibiotics, active against both bacteria and yeast.

Results

To better assess its capabilities, the complete genome sequence of S. espanaensis was established. With a size of 9,360,653 bp, coding for 8,501 genes, it stands alongside other Pseudonocardiaceae with large genomes. Besides a predicted core genome of 810 genes shared in the family, S. espanaensis has a large number of accessory genes: 2,967 singletons when compared to the family, of which 1,292 have no clear orthologs in the RefSeq database. The genome analysis revealed the presence of 26 biosynthetic gene clusters potentially encoding secondary metabolites. Among them, the cluster coding for the saccharomicins could be identified.

Conclusion

S. espanaensis is the first completely sequenced species of the genus Saccharothrix. The genome discloses the cluster responsible for the biosynthesis of the saccharomicins, the largest oligosaccharide antibiotic currently identified. Moreover, the genome revealed 25 additional putative secondary metabolite gene clusters further suggesting the strain’s potential for natural product synthesis.

Pseudonocardia hispaniensis sp. nov., a novel actinomycete isolated from industrial wastewater activated sludge

A novel actinomycete, designated PA3(T), was isolated from an oil refinery wastewater treatment plant, located in Palos de la Frontera, Huelva, Spain, and characterized taxonomically by using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences showed that the isolate formed a distinct subclade in the Pseudonocardia tree together with Pseudonocardia asaccharolytica DSM 44247(T). The chemotaxonomic properties of the isolate, for example, the presence of MK-8 (H(4)) as the predominant menaquinone and iso-C(16:0) as the major fatty acid, are consistent with its classification in the genus Pseudonocardia. DNA:DNA pairing experiments between the isolate and the type strain of P. asaccharolytica DSM 44247(T) showed that they belonged to separate genomic species. The two strains were readily distinguished using a combination of phenotypic properties. Consequently, it is proposed that isolate PA3(T) represents a novel species for which the name Pseudonocardia hispaniensis sp. nov. is proposed. The type strain is PA3(T) (= CCM 8391(T) = CECT 8030(T)).

Labedaea rhizosphaerae gen. nov., sp. nov., isolated from rhizosphere soil

A novel actinomycete, designated strain RS-49T, was isolated from the rhizosphere soil of a cliff-associated plant (Peucedanum japonicum Thunb.) in the Republic of Korea and subjected to a polyphasic taxonomic study. The results of comparative 16S rRNA gene sequence analyses showed that the organism belonged to the family Pseudonocardiaceae , suborder Pseudonocardineae and that it was most closely related to members of the genera Kibdelosporangium (96.6–97.0 % sequence similarity), Actinokineospora (96.3–96.7 %), Streptoalloteichus (96.2 %) and Actinophytocola (96.2 %). Substrate mycelia were well-developed and whitish or pale yellow to strong yellow. Aerial mycelia were branched and fragmented into rod-shaped elements. Single spherical spores were produced directly on the substrate mycelium. Sporangium-like structures and fragmentation of the substrate mycelium were absent. The diagnostic diamino acid in the cell-wall peptidoglycan was meso-diaminopimelic acid. The acyl type of the muramic acid residues in the peptidoglycan was N-acetylated. Whole-cell sugars were glucose, rhamnose, galactose, ribose, mannose, arabinose and xylose. The major menaquinone was MK-9(H4). Small amounts of MK-8 and MK-9(H2) were also detected. The polar lipids contained diphosphatidylglycerol, phosphatidyldimethylethanolamine, phosphatidylglycerol, phosphatidylinositol, an unknown phospholipid and an unknown lipid. The predominant fatty acids were iso-C15 : 0 and iso-C16 : 0. The DNA G+C content was 64.2 mol%. The phenotypic and phylogenetic characteristics show that strain RS-49T can be differentiated from members of all genera in the suborder Pseudonocardineae and thus represents a novel species in a new genus for which the name Labedaea rhizosphaerae gen. nov., sp. nov. is proposed; the type strain of the type species is RS-49T ( = KCTC 19662T = DSM 45361T).

Amycolatopsis magusensis sp. nov., isolated from soil

A novel actinomycete, designated strain KT2025(T), was isolated from arid soil collected from Magusa, northern Cyprus. The taxonomic position of the novel strain was established by using a polyphasic approach. The organism had chemical and morphological features consistent with its classification in the genus Amycolatopsis. Phylogenetic analyses based on 16S rRNA gene sequences supported the classification of the isolate in the genus Amycolatopsis and showed that the organism formed a cluster with Amycolatopsis nigrescens CSC17-Ta-90(T), Amycolatopsis minnesotensis 32U-2(T), Amycolatopsis sacchari DSM 44468(T) and Amycolatopsis dongchuanensis YIM 75904(T). 16S rRNA gene sequence similarity analysis indicated that strain KT2025(T) was most closely related to Amycolatopsis lurida DSM 43134(T) (97.5 %), Amycolatopsis keratiniphila subsp. keratiniphila DSM 44409(T) (97.4 %), Amycolatopsis keratiniphila subsp. nogabecina DSM 44586(T) (97.1 %), Amycolatopsis nigrescens DSM 44992(T) (97.1 %), Amycolatopsis azurea DSM 43854(T) (97.1 %) and Amycolatopsis minnesotensis DSM 44988(T) (96.9 %). The organism was found to have chemical features typical of members of the genus Amycolatopsis such as meso-diaminopimelic acid as the diagnostic diamino acid in the cell-wall peptidoglycan, and arabinose and galactose as diagnostic sugars. The predominant menaquinone was MK-9(H4). The polar lipids detected were phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol and hydroxy-phosphatidylethanolamine. The major fatty acids were iso-C16 : 0, iso-C15 : 0 and iso-C14 : 0. The G+C content of the genomic DNA was 70.8 mol%. Phenotypic data clearly distinguished the isolate from its closest relatives. The combined genotypic and phenotypic data and low levels of DNA-DNA relatedness with its closest relatives indicated that strain KT2025(T) represents a novel species of the genus Amycolatopsis, for which the name Amycolatopsis magusensis sp. nov. is proposed. The type strain is KT2025(T) ( = DSM 45510(T) = KCTC 29056(T)).

Genome sequence of the soil bacterium Saccharomonospora azurea type strain (NA-128(T))

Saccharomonospora azurea Runmao et al. 1987 is a member of the genus Saccharomonospora, which is in the family Pseudonocardiaceae and thus far poorly characterized genomically. Members of the genus Saccharomonospora are of interest because they originate from diverse habitats, such as leaf litter, manure, compost, the surface of peat, and moist and over-heated grain, and may play a role in the primary degradation of plant material by attacking hemicellulose. Next to S. viridis, S. azurea is only the second member in the genus Saccharomonospora for which a completely sequenced type strain genome will be published. Here we describe the features of this organism, together with the complete genome sequence with project status 'Improved high quality draft', and the annotation. The 4,763,832 bp long chromosome with its 4,472 protein-coding and 58 RNA genes was sequenced as part of the DOE funded Community Sequencing Program (CSP) 2010 at the Joint Genome Institute (JGI).

Genome sequence of the ocean sediment bacterium Saccharomonospora marina type strain (XMU15(T))

Saccharomonospora marina Liu et al. 2010 is a member of the genus Saccharomonospora, in the family Pseudonocardiaceae that is poorly characterized at the genome level thus far. Members of the genus Saccharomonospora are of interest because they originate from diverse habitats, such as leaf litter, manure, compost, surface of peat, moist, over-heated grain, and ocean sediment, where they might play a role in the primary degradation of plant material by attacking hemicellulose. Organisms belonging to the genus are usually Gram-positive staining, non-acid fast, and classify among the actinomycetes. Here we describe the features of this organism, together with the complete genome sequence (permanent draft status), and annotation. The 5,965,593 bp long chromosome with its 5,727 protein-coding and 57 RNA genes was sequenced as part of the DOE funded Community Sequencing Program (CSP) 2010 at the Joint Genome Institute (JGI).

Amycolatopsis bartoniae sp. nov. and Amycolatopsis bullii sp. nov., mesophilic actinomycetes isolated from arid Australian soils

The status of two mesophilic filamentous actinomycetes isolated from an arid Australian soil sample was determined using a polyphasic taxonomic approach. The isolates had chemical and morphological properties consistent with their classification in the genus Amycolatopsis, assignments that were supported by analysis of 16S rRNA gene sequence data. Isolate SF26(T) formed a distinct phyletic line and hence was sharply separated from its nearest phylogenetic neighbour, Amycolatopsis sacchari DSM 44468(T). In contrast, isolate SF27(T) formed a subclade in the Amycolatopsis tree with Amycolatopsis vancoresmycina DSM 44592(T) but was separated readily from the latter by DNA:DNA pairing data. The two isolates were distinguished from one another and from their respective nearest phylogenetic neighbours using a range of phenotypic properties. These data indicate that the two isolates should be recognized as new species in the genus Amycolatopsis. The names proposed for these new taxa are Amycolatopsis bartoniae sp. nov. and Amycolatopsis bullii sp. nov. with isolates SF26(T) (=NCIMB 14706(T) = NRRL B-2846(T)) and SF27(T) (=NCIMB 14707(T) = NRRL B-24847(T)) as the respective type strains.

Phylogenetic framework and molecular signatures for the main clades of the phylum Actinobacteria

The phylum Actinobacteria harbors many important human pathogens and also provides one of the richest sources of natural products, including numerous antibiotics and other compounds of biotechnological interest. Thus, a reliable phylogeny of this large phylum and the means to accurately identify its different constituent groups are of much interest. Detailed phylogenetic and comparative analyses of >150 actinobacterial genomes reported here form the basis for achieving these objectives. In phylogenetic trees based upon 35 conserved proteins, most of the main groups of Actinobacteria as well as a number of their superageneric clades are resolved. We also describe large numbers of molecular markers consisting of conserved signature indels in protein sequences and whole proteins that are specific for either all Actinobacteria or their different clades (viz., orders, families, genera, and subgenera) at various taxonomic levels. These signatures independently support the existence of different phylogenetic clades, and based upon them, it is now possible to delimit the phylum Actinobacteria (excluding Coriobacteriia) and most of its major groups in clear molecular terms. The species distribution patterns of these markers also provide important information regarding the interrelationships among different main orders of Actinobacteria. The identified molecular markers, in addition to enabling the development of a stable and reliable phylogenetic framework for this phylum, also provide novel and powerful means for the identification of different groups of Actinobacteria in diverse environments. Genetic and biochemical studies on these Actinobacteria-specific markers should lead to the discovery of novel biochemical and/or other properties that are unique to different groups of Actinobacteria.

Actinophytocola xinjiangensis sp. nov., isolated from virgin forest soil

An aerobic, non-motile actinobacterium, strain QAIII60T, was isolated from virgin forest soil of Kanas Nature Reserve, Xinjiang, north-west China. The isolate produced a very scant aerial mycelium that fragmented into cylindrical spores and a non-fragmented substrate mycelium with occasional septa. Whole-cell hydrolysates contained meso-diaminopimelic acid, arabinose, galactose, glucose, ribose and rhamnose (trace). The diagnostic polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, hydroxyphosphatidylethanolamine and ninhydrin-positive phosphoglycolipids. The major cellular fatty acids were iso-C16 : 0, iso-C14 : 0, iso-C16 : 1 H and C17 : 1ω6c. The isoprenoid quinones consisted of MK-9(H4) and MK-10(H2). The G+C content of the genomic DNA was 72.5 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain QAIII60T formed a distinct phyletic line that was most closely, albeit loosely, associated with the genus Actinophytocola. A number of physiological characteristics differentiated the isolate from members of the genus Actinophytocola. On the basis of these data, we propose that strain QAIII60T ( = CGMCC 4.4663T  = NBRC 106673T) be assigned as the type strain of a novel species, Actinophytocola xinjiangensis sp. nov.

Lentzea jiangxiensis sp. nov., isolated from acidic soil

A novel actinomycete, designated strain FXJ1.034(T), was isolated from acidic soil collected in Jiangxi Province, South-east China. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain FXJ1.034(T) belonged to the genus Lentzea and showed high sequence similarities to Lentzea kentuckyensis NRRL B-24416(T) (98.5%) and Lentzea albida NBRC 16102(T) (98.3%). Morphological and chemotaxonomic characteristics supported its assignment to the genus Lentzea. The results of DNA-DNA hybridization, physiological and biochemical tests allowed genotypic and phenotypic differentiation of the novel strain from closely related species. Based on the evidence presented here, strain FXJ1.034(T) represents a novel species of the genus Lentzea, for which the name Lentzea jiangxiensis sp. nov. is proposed. The type strain is FXJ1.034(T) ( = CGMCC 4.6609(T)  = NBRC 106680(T)).

Amycolatopsis granulosa sp. nov., Amycolatopsis ruanii sp. nov. and Amycolatopsis thermalba sp. nov., thermophilic actinomycetes isolated from arid soils

The taxonomic positions of three thermophilic actinomycetes isolated from arid soil samples were established by using a polyphasic approach. The organisms had chemical and morphological features that were consistent with their classification in the genus Amycolatopsis. 16S rRNA gene sequence data supported the classification of the isolates in the genus Amycolatopsis and showed that they formed distinct branches in the Amycolatopsis methanolica subclade. DNA-DNA relatedness studies between the isolates and their phylogenetic neighbours showed that they belonged to distinct genomic species. The three isolates were readily distinguished from one another and from the type strains of species classified in the A. methanolica subclade based on a combination of phenotypic properties and by genomic fingerprinting. Consequently, it is proposed that the three isolates be classified in the genus Amycolatopsis as representatives of Amycolatopsis granulosa sp. nov. (type strain GY307(T) = NCIMB 14709(T) = NRRL B-24844(T)), Amycolatopsis ruanii sp. nov. (type strain NMG112(T) = NCIMB 14711(T) = NRRL B-24848(T)) and Amycolatopsis thermalba sp. nov. (type strain SF45(T) = NCIMB 14705(T) = NRRL B-24845(T)).

Amycolatopsis thermophila sp. nov. and Amycolatopsis viridis sp. nov., thermophilic actinomycetes isolated from arid soil

The taxonomic positions of two thermophilic actinomycetes isolated from an arid Australian soil sample were established based on an investigation using a polyphasic taxonomic approach. The organisms had chemical and morphological properties typical of members of the genus Amycolatopsis and formed distinct phyletic lines in the Amycolatopsis methanolica 16S rRNA subclade. The two organisms were distinguished from one another and from the type strains of related species of the genus Amycolatopsis using a range of phenotypic properties. Based on the combined genotypic and phenotypic data, it is proposed that the two isolates be classified in the genus Amycolatopsis as Amycolatopsis thermophila sp. nov. (type strain GY088(T)=NCIMB 14699(T)=NRRL B-24836(T)) and Amycolatopsis viridis sp. nov. (type strain GY115(T)=NCIMB 14700(T)=NRRL B-24837(T)).