Nonomuraea maheshkhaliensis sp. nov., a novel actinomycete isolated from mangrove rhizosphere mud

Polyphasic classification of Nonomuraea strains isolated from the Karakum Desert and description of Nonomuraea deserti sp. nov., Nonomuraea diastatica sp. nov., Nonomuraea longispora sp. nov. and Nonomuraea mesophila sp. nov

Five actinobacteria isolates, KC201^T, KC401, KC310^T, KC712^T and 6K102^T, were recovered from the Karakum Desert during an investigation of novel actinobacteria with biotechnological potential. A polyphasic approach confirmed the affiliation of the strains to the genus Nonomuraea. The strains showed chemotaxonomic and morphological properties consistent with their classification in the genus Nonomuraea. Furthermore, these strains clearly distinguished and formed well supperted clades in phylogenetic and phylogenomic trees. Low ANI and dDDH values and distinguishing phenotypic properties between isolates KC201^T, KC310^T, KC712^T and 6K102^T showed that these strains belonged to novel Nonomuraea species, the names proposed for these taxa are Nonomuraea deserti sp. nov., Nonomuraea diastatica sp. nov., Nonomuraea longispora sp. nov. and Nonomuraea mesophila sp. nov., with the type strains KC310^T (=CGMCC 4.7331^T =DSM 102919^T =KCTC 39774^T), KC712^T (=CGMCC 4.7334^T =DSM 102925^T =KCTC 39776), KC201^T (=CGMCC 4.7339^T =DSM 102917^T =KCTC 39781^T) and 6K102^T (=CGMCC 4.7541^T =JCM 32916), respectively.

Nonomuraea phyllanthi sp. nov., an endophytic actinomycete isolated from the leaf of Phyllanthus amarus

A novel actinomycete, strain PA1-10^T, isolated from the leaf of Phyllanthus amarus collected from Bangkok, Thailand, was characterized taxonomically using a polyphasic approach. This strain contained the characteristics consistent with those of members of the genus Nonomuraea. It formed short rugose spore chain on aerial mycelium. The diamino acid in cell wall peptidoglycan was meso-diaminopimelic acid. Galactose, glucose, madurose, mannose, and ribose were found in whole-cell hydrolysates. Predominant menaquinones were MK-9 (H₂), MK-9 (H₄), and MK-9 (H₆). Major cellular fatty acids were iso-C_16:0 and C_17:0 10-methyl. Phospholipid profiles were composed of phosphatidylinositol mannoside (PIM), lyso-phosphatidylethanolamine (lyso-PE), phosphatidylethanolamine (PE), methylphosphatidylethanolamine (PME), diphosphatidylglycerol (DPG), and phosphatidylglycerol (PG). The G + C content of DNA was 71.2 mol%. Strain PA1-10^T showed the highest 16S rRNA gene sequence similarity with Nonomuraea candida JCM 15928^T (98.35%) and shared the same node with Nonomuraea maritima JCM 18321^T in the phylogenetic tree analysis. Based on the phenotypic characteristics, DNA-DNA relatedness, and average nucleotide identity (ANI), the strain is considered to represent a novel species of the genus Nonomuraea, for which the name Nonomuraea phyllanthi is proposed. The type strain is PA1-10^T (= JCM 33073^T = NBRC 112774^T = TISTR 2497^T).

Diversity and Applications of Endophytic Actinobacteria of Plants in Special and Other Ecological Niches

Actinobacteria are wide spread in nature and represent the largest taxonomic group within the domain Bacteria. They are abundant in soil and have been extensively explored for their therapeutic applications. This versatile group of bacteria has adapted to diverse ecological habitats, which has drawn considerable attention of the scientific community in recent times as it has opened up new possibilities for novel metabolites that may help in solving some of the most challenging problems of the day, for example, novel drugs for drug-resistant human pathogens, affordable means to maintain ecological balance in various habitats, and alternative practices for sustainable agriculture. Traditionally, free dwelling soil actinobacteria have been the subject of intensive research. Of late, symbiotic actinobacteria residing as endophytes within the plant tissues have generated immense interest as potential source of novel compounds, which may find applications in medicine, agriculture, and environment. In the light of these possibilities, this review focuses on the diversity of endophytic actinobacteria isolated from the plants of extreme habitats and specific ecological niches. Furthermore, an attempt has been made to assign chemical class to the compounds obtained from endophytic actinobacteria. Potential therapeutic applications of these compounds and the utility of endophytic actinobacteria in agriculture and environment are discussed.

Classification of Nonomuraea sp. ATCC 39727, an actinomycete that produces the glycopeptide antibiotic A40926, as Nonomuraea gerenzanensis sp. nov

Strain ATCC 39727, which produces the antibiotic A40926 (the natural precursor of the antibiotic dalbavancin), was isolated from a soil sample collected in India, and it was originally classified as a member of the genus Actinomadura on the base of morphology and cell-wall composition. A phylogenetic analysis based on 16S rRNA gene sequences indicates that the strain forms a distinct clade within the genus Nonomuraea, and it is most closely related to Nonomuraea angiospora DSM 43173T (98.72 % similarity) and Nonomuraea jabiensis A4036T (98.69 %). The strain forms an extensively branched substrate mycelium and aerial hyphae that form spiral chains of spores with ridged surfaces. The cell wall contains meso-diaminopimelic acid and the whole-cell sugars are glucose, ribose, galactose, mannose and madurose (madurose as the diagnostic sugar). The N-acyl type of muramic acid is acetyl. The predominant menaquinone is MK-9(H4), with minor amounts of MK-9(H2), MK-9(H6) and MK-9(H0). The polar-lipid profile includes diphosphatidylglycerol, phosphatidylethanolamine, hydroxyphosphatidylethanolamine, phosphatidylmethylethanolamine, hydroxyphosphatidylmethylethanolamine, phosphatidylinositol and a series of uncharacterized phospholipids, glycolipids and phosphoglycolipids. The major cellular fatty acids are iso-C16 : 0 and 10-methyl C17 : 0. The genomic DNA G+C content is 71.2 mol%. Significant differences in the morphological, chemotaxonomic and biochemical data, together with DNA-DNA relatedness between strain ATCC 39727 and closely related type strains, clearly demonstrated that strain ATCC 39727 represents a novel species of the genus Nonomuraea, for which the name Nonomuraea gerenzanensis sp. nov. is proposed. The type strain is ATCC 39727T ( = DSM 100948T).

Broad Spectrum Antimicrobial Activity of Forest-Derived Soil Actinomycete, Nocardia sp. PB-52

A mesophilic actinomycete strain designated as PB-52 was isolated from soil samples of Pobitora Wildlife Sanctuary of Assam, India. Based on phenotypic and molecular characteristics, the strain was identified as Nocardia sp. which shares 99.7% sequence similarity with Nocardia niigatensis IFM 0330 (NR_112195). The strain is a Gram-positive filamentous bacterium with rugose spore surface which exhibited a wide range of antimicrobial activity against Gram-positive bacteria including methicillin-resistant Staphylococcus aureus (MRSA), Gram-negative bacteria, and yeasts. Optimization for the growth and antimicrobial activity of the strain PB-52 was carried out in batch culture under shaking condition. The optimum growth and antimicrobial potential of the strain were recorded in GLM medium at 28°C, initial pH 7.4 of the medium and incubation period of 8 days. Based on polyketide synthases (PKS) and non-ribosomal peptide synthetases (NRPS) gene-targeted PCR amplification, the occurrence of both of these biosynthetic pathways was detected which might be involved in the production of antimicrobial compounds in PB-52. Extract of the fermented broth culture of PB-52 was prepared with organic solvent extraction method using ethyl acetate. The ethyl acetate extract of PB-52 (EA-PB-52) showed lowest minimum inhibitory concentration (MIC) against S. aureus MTCC 96 (0.975 μg/mL) whereas highest was recorded against Klebsiella pneumoniae ATCC 13883 (62.5 μg/mL). Scanning electron microscopy (SEM) revealed that treatment of the test microorganisms with EA-PB-52 destroyed the targeted cells with prominent loss of cell shape and integrity. In order to determine the constituents responsible for its antimicrobial activity, EA-PB-52 was subjected to chemical analysis using gas chromatography-mass spectrometry (GC-MS). GC-MS analysis showed the presence of twelve different chemical constituents in the extract, some of which are reported to possess diverse biological activity. These results confirmed that the presence of bioactive constituents in EA-PB-52 could be a promising source for the development of potent antimicrobial agents effective against wide range of microbial pathogens including MRSA.

Mangrove rare actinobacteria: taxonomy, natural compound, and discovery of bioactivity

Actinobacteria are one of the most important and efficient groups of natural metabolite producers. The genus Streptomyces have been recognized as prolific producers of useful natural compounds as they produced more than half of the naturally-occurring antibiotics isolated to-date and continue as the primary source of new bioactive compounds. Lately, Streptomyces groups isolated from different environments produced the same types of compound, possibly due to frequent genetic exchanges between species. As a result, there is a dramatic increase in demand to look for new compounds which have pharmacological properties from another group of Actinobacteria, known as rare actinobacteria; which is isolated from special environments such as mangrove. Recently, mangrove ecosystem is becoming a hot spot for studies of bioactivities and the discovery of natural products. Many novel compounds discovered from the novel rare actinobacteria have been proven as potential new drugs in medical and pharmaceutical industries such as antibiotics, antimicrobials, antibacterials, anticancer, and antifungals. This review article highlights the latest studies on the discovery of natural compounds from the novel mangrove rare actinobacteria and provides insight on the impact of these findings.

Characterization of antibiotic producing rare actinomycete Nonomuraea sp. JAJ18 derived from an Indian coastal solar saltern

Rare actinomycete genera are accepted as a promising source of novel metabolites having pharmaceutical importance. One such genus of rare actinomycete is Nonomuraea. The present study was aimed at characterizing the antibiotic producing Nonomuraea strain JAJ18 which was previously isolated from coastal solar saltern. Strain JAJ18 was recognized as a member of genus Nonomuraea based on its almost complete 16S rRNA gene sequence and phenotypic characteristics. The strain JAJ18 was found to be closely related to Nonomuraea maheshkhaliensis 16-5-14(T) (98.90%), Nonomuraea candida HMC10(T) (98.58%), and Nonomuraea jabiensis A4036(T) (98.43%). From cell-free culture broth of strain JAJ18, an antibiotic was extracted and purified by silica column chromatography. The obtained antibiotic was found to be active against a range of Gram-positive and Gram-negative bacteria including drug-resistant Staphylococcus, with minimal inhibitory concentration (MIC) ranging from 0.5 to 16.0 µg mL(-1). The structural characteristics of antibiotic were determined by FTIR and NMR spectroscopy. The antibiotic was identified to be an aliphatic rich compound with significant dissimilarity to known antibiotics reported from members of the genus, Nonomuraea. As the trends to discover novel metabolites from Nonomuraea are vibrant, further studies are needed to understand the structural and biotechnological significance of antibiotic compound produced by Nonomuraea sp. JAJ18.

Diversity and antimicrobial activities of actinobacteria isolated from tropical mangrove sediments in Malaysia

The aim of this study was to isolate and identify Actinobacteria from Malaysia mangrove forest and screen them for production of antimicrobial secondary metabolites. Eighty-seven isolates were isolated from soil samples collected at 4 different sites. This is the first report to describe the isolation of Streptomyces, Mycobacterium, Leifsonia, Microbacterium, Sinomonas, Nocardia, Terrabacter, Streptacidiphilus, Micromonospora, Gordonia, and Nocardioides from mangrove in east coast of Malaysia. Of 87 isolates, at least 5 isolates are considered as putative novel taxa. Nine Streptomyces sp. isolates were producing potent antimicrobial secondary metabolites, indicating that Streptomyces isolates are providing high quality metabolites for drug discovery purposes. The discovery of a novel species, Streptomyces pluripotens sp. nov. MUSC 135^T that produced potent secondary metabolites inhibiting the growth of MRSA, had provided promising metabolites for drug discovery research. The biosynthetic potential of 87 isolates was investigated by the detection of polyketide synthetase (PKS) and nonribosomal polyketide synthetase (NRPS) genes, the hallmarks of secondary metabolites production. Results showed that many isolates were positive for PKS-I (19.5%), PKS-II (42.5%), and NRPS (5.7%) genes, indicating that mangrove Actinobacteria have significant biosynthetic potential. Our results highlighted that mangrove environment represented a rich reservoir for isolation of Actinobacteria, which are potential sources for discovery of antimicrobial secondary metabolites.

Nonomuraea muscovyensis sp. nov., isolated from soil

A novel actinomycete, strain FMN03T, was isolated from a soil sample collected from Yuga Zapadnaya South-West Forest Park, Moscow, Russia. The isolate had chemical and morphological properties typical of members of the genus Nonomuraea and formed a distinct 16S rRNA gene subclade with the type strains Nonomuraea roseoviolacea subsp. carminata NBRC 15903T and Nonomuraea roseoviolacea subsp. roseoviolacea NBRC 14098T. The organism formed extensively branched substrate and aerial hyphae, which generated spiral chains of spores with smooth surfaces. The cell wall contained meso-diaminopimelic acid and the whole cell sugars were glucose, galactose and trace amounts of madurose, mannose and xylose. The polar lipids were phosphatidylethanolamine, hydroxyphosphatidylethanolamine, four unidentified phospholipids, four unidentified glycolipids and one unidentified lipid. The predominant menaquinone was MK-9(H4). The major fatty acids were iso-C16 : 0 2-OH, C17 : 0 10-methyl, C17 : 1 cis9 and iso-C16 : 0. Analyses of its morphological, physiological and biochemical characteristics, together with DNA–DNA relatedness data, confirmed that strain FMN03T is a representative of a novel species of the genus Nonomuraea , which is distinct from closely related reference strains. Strain FMN03T ( = DSM 45913T = KCTC 29233T) is proposed as the type strain of a novel species, for which the name Nonomuraea muscovyensis sp. nov. is proposed.

Alkaloids from the mangrove-derived actinomycete Jishengella endophytica 161111

A new alkaloid, 2-(furan-2-yl)-6-(2S,3S,4-trihydroxybutyl)pyrazine (1), along with 12 known compounds, 2-(furan-2-yl)-5-(2S,3S,4-trihydroxybutyl)pyrazine (2), (S)-4-isobutyl-3-oxo-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazine-6-carbaldehyde (3), (S)-4-isopropyl-3-oxo-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazine-6-carbaldehyde (4), (4S)-4-(2-methylbutyl)-3-oxo-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazine-6-carbaldehyde (5), (S)-4-benzyl-3-oxo-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazine-6-carbaldehyde (6), flazin (7), perlolyrine (8), 1-hydroxy-β-carboline (9), lumichrome (10), 1H-indole-3-carboxaldehyde (11), 2-hydroxy-1-(1H-indol-3-yl)ethanone (12), and 5-(methoxymethyl)-1H-pyrrole-2-carbaldehyde (13), were isolated and identified from the fermentation broth of an endophytic actinomycetes, Jishengella endophytica 161111. The new structure 1 and the absolute configurations of 2–6 were determined by spectroscopic methods, J-based configuration analysis (JBCA) method, lactone sector rule, and electronic circular dichroism (ECD) calculations. Compounds 8–11 were active against the influenza A virus subtype H1N1 with IC₅₀ and selectivity index (SI) values of 38.3(±1.2)/25.0(±3.6)/39.7(±5.6)/45.9(±2.1) μg/mL and 3.0/16.1/3.1/11.4, respectively. The IC₅₀ and SI values of positive control, ribavirin, were 23.1(±1.7) μg/mL and 32.2, respectively. The results showed that compound 9 could be a promising new hit for anti-H1N1 drugs. The absolute configurations of 2–5, ¹³C nuclear magnetic resonance (NMR) data and the specific rotations of 3–6 were also reported here for the first time.

Nonomuraea jabiensis sp. nov., isolated from arid soil

A novel actinomycete, strain A4036T, was isolated from a soil sample collected from the Jabi district in Abuja, Nigeria. The taxonomic position of strain A4036T was established using a combination of genotypic and phenotypic analyses. The organism formed extensively branched substrate and aerial hyphae that generated spiral chains of spores with warty surfaces. The cell wall contained meso-diaminopimelic acid and the cell-wall sugars were glucose, madurose, mannose and ribose. The predominant menaquinone was MK-9(H4). The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, phosphatidylmethylethanolamine, phosphatidylinositol mannoside, hydroxy-phosphatidylethanolamine, hydroxy-phosphatidylmethylethanolamine, two unidentified phospholipids and four unknown glucosamine-containing phospholipids. The major cellular fatty acids were iso-C16 : 0 2-OH, iso-C16 : 0 and 10-methyl C17 : 0. On the basis of 16S rRNA gene sequence similarity studies, strain A4036T grouped in the genus Nonomuraea , being most closely related to Nonomuraea angiospora IFO 13155T (99.05 %), Nonomuraea candida HMC10T (98.78 %), Nonomuraea kuesteri GW 14-1925T (98.49 %), Nonomuraea endophytica YIM 65601T (98.42 %), Nonomuraea maheshkhaliensis 16-5-14T (98.40 %), Nonomuraea turkmeniaca DSM 43926T (98.38 %), Nonomuraea helvata IFO 14681T (98.29 %), Nonomuraea rubra DSM 43768T (98.10 %) and Nonomuraea salmonea DSM 43678T (98.06 %). Levels of 16S rRNA gene sequence similarity to the type strains of other species of the genus Nonomuraea were <98 %. Despite the high 16S rRNA gene sequence similarities, DNA–DNA relatedness values and phenotypic data demonstrated that strain A4036T was clearly distinguished from all closely related species of the genus Nonomuraea . Thus, this isolate is considered to represent a novel species of the genus Nonomuraea , for which the name Nonomuraea jabiensis sp. nov. is proposed. The type strain is A4036T ( = DSM 45507T = KCTC 19870T).

Nonomuraea solani sp. nov., an actinomycete isolated from eggplant root (Solanum melongena L.)

A novel actinomycete, designated strain NEAU-Z6(T), was isolated from eggplant (Solanum melongena L.) root. Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain NEAU-Z6(T) belonged to the genus Nonomuraea, with highest sequence similarity to Nonomuraea monospora PT 708(T) (98.83 %), Nonomuraea rosea GW 12687(T) (98.55 %) and Nonomuraea rhizophila YIM 67092(T) (98.02 %). Sequence similarities between strain NEAU-Z6(T) and other species of the genus Nonomuraea ranged from 97.94 % (Nonomuraea candida HMC10(T)) to 96.30 % (Nonomuraea wenchangensis 210417(T)). Key morphological, physiological and chemotaxonomic characteristics of strain NEAU-Z6(T) were congruent with the description of the genus Nonomuraea. The G+C content of the genomic DNA was 64.51 mol%. DNA-DNA relatedness and comparative analysis of physiological, biochemical and chemotaxonomic data allowed genotypic and phenotypic differentiation of strain NEAU-Z6(T) from closely related species. Thus, strain NEAU-Z6(T) represents a novel species of the genus Nonomuraea, for which the name Nonomuraea solani sp. nov. is proposed. The type strain is NEAU-Z6(T) ( = CGMCC 4.7037(T) = DSM 45729(T)).

Phylogenetic diversity of actinomycetes cultured from coastal multipond solar saltern in Tuticorin, India

BACKGROUND

Hypersaline solar salterns are extreme environments in many tropical and subtropical regions throughout the world. In India, there are several coastal solar salterns along with the coastal line of the Bay of Bengal and Arabian Sea and inland solar salterns around Sambhar saltlake, from which sodium chloride is obtained for human consumption and industrial needs. Studies on characterization of such coastal and inland solar salterns are scarce and both the bacterial and archaeal diversity of these extreme saline environment remains poorly understood. Moreover, there are no reports on exclusive diversity of actinomycetes inhabiting Indian solar salterns.

RESULTS

Soil sediments were collected from both concentrator and crystallizer ponds of solar salterns and subjected to detailed physico-chemical analysis. Actinomycetes were selectively isolated by employing selective processing methods and agar media. A total of 12 representatives were selected from the 69 actinomycete isolates obtained from the saltern soil samples, using Amplified Ribosomal DNA Restriction Analysis. Sequencing and analysis of 16S rDNA from chosen representative isolates displayed the presence of members affiliated to actinobacterial genera: Streptomyces, Micromonospora, Nocardia, Nocardiopsis, Saccharopolyspora and Nonomuraea. The genus Streptomyces was found to be the dominant among the isolates. Furthermore, rare actinomycete genus Nonomuraea was isolated for the first time from Indian solar salterns.

CONCLUSIONS

To the best of our knowledge, this study constitutes the first characterization of actinomycete diversity centred on solar salterns located in the eastern coastal region of India. Furthermore, this is the very first report of isolation of Nonomuraea species from solar salterns and also from India. As actinomycetes encompass recurrently foremost sources of biotechnologically important member of the microbial communities, the actinomycetes retrieved from the Indian saltern soil samples laid the platform to search for novel biotechnologically significant bioactive substances.

Nonomuraea jiangxiensis sp. nov., isolated from acidic soil

An actinomycete, designated FXJ1.102T, was isolated from acidic soil collected in Jiangxi Province, south-east China. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain FXJ1.102T belonged to the genus Nonomuraea and was most closely related to Nonomuraea candida HMC10T, Nonomuraea turkmeniaca DSM 43926T, Nonomuraea antimicrobica YIM 61105T and ‘Nonomuraea aegyptia’ S136 (98.9, 98.3, 97.9 and 97.5 % 16S rRNA gene sequence similarities, respectively). The morphological characteristics were typical of the genus Nonomuraea . The chemotaxonomic properties, such as cell-wall chemotype IIIB, phospholipid type IV, MK-9(H4) as the major menaquinone and iso-C16 : 0 (22.2 %) as the major fatty acid, supported the assignment of the strain to the genus Nonomuraea . DNA–DNA relatedness and physiological tests allowed genotypic and phenotypic differentiation of strain FXJ1.102T from its closest phylogenetic relatives. The isolate therefore represents a novel species, for which the name Nonomuraea jiangxiensis sp. nov. is proposed. The type strain is FXJ1.102T ( = CGMCC 4.6533T = NBRC 106679T).

Nonomuraea monospora sp. nov., an actinomycete isolated from cave soil in Thailand, and emended description of the genus Nonomuraea

A novel actinomycete, designated strain PT708(T), was isolated from cave soil collected in Pha Tup Cave Forest Park, Nan province, Thailand. It produced compounds with antimicrobial and anticancer activities. Its chemotaxonomic properties were consistent with those of members of the genus Nonomuraea. The major menaquinone was MK-9(H(4)), with minor amounts of MK-9(H(6)), MK-9(H(2)), MK-10(H(2)) and MK-8(H(4)). The polar lipid profile contained phosphatidylmonomethylethanolamine, diphosphatidylglycerol, hydroxy-phosphatidylmonomethylethanolamine, hydroxy-phosphatidylethanolamine, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol mannoside and phosphatidylinositol. The major fatty acids were iso-C(16:0), 10-methyl C(17:0), C(16:0) and C(17:1)ω6c. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain PT708(T) belonged to the genus Nonomuraea and was most closely related to Nonomuraea rhizophila YIM 67092(T) (98.50% sequence similarity) and Nonomuraea rosea GW 12687(T) (98.30%). The genomic DNA G+C content of strain PT708(T) was 73.3 mol%. Unlike the recognized members of the genus Nonomuraea, the novel strain formed single spores at the tips of aerial hyphae. Based on the phenotypic, phylogenetic and genotypic evidence, strain PT708(T) represents a novel species of the genus Nonomuraea, for which the name Nonomuraea monospora sp. nov. is proposed. The type strain is PT708(T) ( = TISTR 1910(T) = JCM 16114(T)).

Nonomuraea maritima sp. nov., isolated from coastal sediment

A novel actinomycete, strain FXJ7.203T, was isolated from a coastal sediment sample collected in Bohai Bay, China. In 16S rRNA gene sequence analyses, strain FXJ7.203T always formed a unique monophyletic line within the genus Nonomuraea and was most closely related to Nonomuraea turkmeniaca (97.9 %), Nonomuraea candida (97.8 %), Nonomuraea helvata (97.7 %) and Nonomuraea rubra (97.5 %). Morphological and chemotaxonomic characteristics supported the allocation of the strain to the genus Nonomuraea. The polar lipid profile showed that its phospholipid type was PIV. The major fatty acids were iso-C16 : 0, C17 : 1ω6c, iso-C16 : 1 G, 10-methyl C17 : 0 and iso-C15 : 0. The major menaquinone was MK-9(H4) with minor amounts of MK-9(H2), MK-9(H0) and MK-9(H6). The results of physiological and biochemical tests allowed differentiation of strain FXJ7.203T from closely related species. Based on the genotypic and phenotypic data, strain FXJ7.203T represents a novel species of the genus Nonomuraea, for which the name Nonomuraea maritima sp. nov. is proposed, with strain FXJ7.203T ( = CGMCC 4.5681T  = NBRC 106687T) as the type strain.

Nonomuraea rhizophila sp. nov., an actinomycete isolated from rhizosphere soil

A novel actinomycete, designated strain YIM 67092T, was isolated from rhizosphere soil of the perennial vine Tripterygium wilfordii Hook. f. collected from Yunnan province, South-west China. The strain formed well differentiated aerial and substrate mycelia and grew in the presence of up to 7 % (w/v) NaCl. Phylogenetic analysis based on the 16S rRNA gene showed that strain YIM 67092T belonged to the genus Nonomuraea, with highest sequence similarity to Nonomuraea rosea GW 12687T (99.0 %). Sequence similarities between strain YIM 67092T and other species of the genus Nonomuraea ranged from 97.8 % (Nonomuraea dietziae DSM 44320T) to 93.8 % (Nonomuraea kuesteri GW 14-1925T). Key morphological, physiological and chemotaxonomic characteristics of strain YIM 67092T were congruent with the description of the genus Nonomuraea. The G+C content of the genomic DNA was 69.3 mol%. Based on comparative analysis of physiological, biochemical and chemotaxonomic data, including low DNA–DNA hybridization results, strain YIM 67092T represents a novel species of the genus Nonomuraea, for which the name Nonomuraea rhizophila sp. nov. is proposed. The type strain is YIM 67092T ( = CCTCC AA 209044T  = DSM 45382T).

Nonomuraea rosea sp. nov

A Gram-positively staining, aerobic, non-motile actinomycete, strain GW 12687T, that formed rose-pigmented colonies and branched substrate and aerial mycelia was studied in detail for its taxonomic position. On the basis of 16S rRNA gene sequence similarity studies, strain GW 12687T was grouped into the genus Nonomuraea, being most closely related to Nonomuraea dietziae (97.6 %), Nonomuraea africana (97.1 %), and Nonomuraea kuesteri (97.1 %). The 16S rRNA gene sequence similarity to other species of the genus Nonomuraea was ≤97 %. The chemotaxonomic characterization supported allocation of the strain to the genus Nonomuraea. The major menaquinone was MK-9(H4) with minor amounts of MK-9(H2), MK-9(H6), MK-9(H0) and MK-8(H4). The polar lipid profile contained the major compound diphosphatidylglycerol, moderate amounts of phosphatidylmonomethylethanolamine, phosphatidylethanolamine, hydroxy-phosphatidylethanolamine, hydroxy-phosphatidylmonomethylethanolamine, and an unknown aminophosphoglycolipid. Phosphatidylinositol mannosides and phosphatidylinositol were also present. The major fatty acids were iso- and anteiso- and 10-methyl-branched fatty acids. The results of physiological and biochemical tests allowed genotypic and phenotypic differentiation of strain GW 12687T from closely related species. Thus, GW 12687T represents a novel species of the genus Nonomuraea, for which the name Nonomuraea rosea sp. nov. is proposed, with GW 12687T (=DSM 45177T =CCUG 56107T) as the type strain.

Isolation of an unusual metabolite 2-allyloxyphenol from a marine actinobacterium, its biological activities and applications

A marine actinobacterium isolated from the Bay of Bengal, India and previously found to be producing an antimicrobial and cytotoxic terpenoid was further investigated for antimicrobial metabolites. The bacterium was preliminarily identified as a new species of the genus Streptomyces (strain MS1/7). The cell-free culture broth was extracted with n-butanol and purified using silica gel column chromatography and high-performance liquid chromatography. Molecular characterization was done using ESI mass, IR and 1H and 13C NMR spectrometry. 2-Allyloxyphenol (MW 150; C9H10O2), a synthetic drug and chemical intermediate, was obtained as a natural product for the first time. Serendipitous natural occurrence provided new insights into the synthetic molecule. 2-Allyloxyphenol was found to be inhibitory to 21 bacteria and three fungi in the minimum range 0.2-1.75 mg mL(-1) determined by agar dilution method. 2-Allyoxyphenol possesses strong antioxidant property (IC(50) 22 microg mL(-1), measured by 1, 1-diphenyl-2-picryl hydrazyl scavenging activity). Hydroxyl and allyloxy groups in 2-allyloxyphenol were responsible for antimicrobial and antioxidant activities. 2-Allyloxyphenol has marked resemblance to smoky aroma and is two to three times more active as an antimicrobial than some commercial smoke-flavour compounds. Absence of hemolytic toxicity, potential carcinogenicity, cytotoxicity and reports of toxic reactions in literature suggest possible application of 2-allyloxyphenol as a food preservative and an oral disinfectant.

Actinomycetes for marine drug discovery isolated from mangrove soils and plants in China

The mangrove ecosystem is a largely unexplored source for actinomycetes with the potential to produce biologically active secondary metabolites. Consequently, we set out to isolate, characterize and screen actinomycetes from soil and plant material collected from eight mangrove sites in China. Over 2,000 actinomycetes were isolated and of these approximately 20%, 5%, and 10% inhibited the growth of Human Colon Tumor 116 cells, Candida albicans and Staphylococcus aureus, respectively, while 3% inhibited protein tyrosine phosphatase 1B (PTP1B), a protein related to diabetes. In addition, nine isolates inhibited aurora kinase A, an anti-cancer related protein, and three inhibited caspase 3, a protein related to neurodegenerative diseases. Representative bioactive isolates were characterized using genotypic and phenotypic procedures and classified to thirteen genera, notably to the genera Micromonospora and Streptomyces. Actinomycetes showing cytotoxic activity were assigned to seven genera whereas only Micromonospora and Streptomyces strains showed anti-PTP1B activity. We conclude that actinomycetes isolated from mangrove habitats are a potentially rich source for the discovery of anti-infection and anti-tumor compounds, and of agents for treating neurodegenerative diseases and diabetes.

Distribution of actinomycetes, their antagonistic behaviour and the physico-chemical characteristics of the world's largest tidal mangrove forest

We examined the relationship between distribution of actinomycetes and antagonistic behaviour with the physico-chemical characteristics of the Sundarbans, off the Bay of Bengal, India. Soil/sediment samples were collected from three regions: near to the sea, intertidal regions and mangrove forests. For the enumeration of actinomycetes, four treatments combining dilution with distilled or sea water with or without heating followed by plating onto starch-casein, glycerol-arginine and starch-nitrate media were done. Dilution with seawater, heating and plating onto starch-casein yielded maximum number of actinomycetes. The highest number of actinomycetes was isolated from an intertidal region having alluvial soil and the lowest from a site containing sandy sediments. Antimicrobial activity was dependent upon seawater. Antimicrobial score of an actinomycetes strain was calculated allotting maximum points to the isolate showing activity against all the test bacteria, next lower point to the isolate showing activity against one less the total and so on. The antagonistic potential (AP) of a sampling site was the ratio of total antimicrobial score of the isolates and their number. The high AP sites were influenced by tides, while the low AP sites were not. Pearson's correlation between soil chemical parameters and microbiological parameters revealed soil nitrogen as the key factor determining the antagonistic activity.

The occurrence of bioactive micromonosporae in aquatic habitats of the Sunshine Coast in Australia

Screening strategies based on the ecological knowledge of antibiotic producing microorganisms and their roles in the natural environment are being increasingly employed in the search for novel antibiotic agents. Micromonosporae are common inhabitants of aquatic habitats and have proved to be a continuing source of novel bioactive compounds including antibacterial and antitumor agents. The ecological distribution and frequency of bioactive micromonosporae in Sunshine Coast region aquatic habitats were studied through a range of selective isolation procedures designed to negatively select against the isolation of unwanted microbial taxa commonly associated with marine environments. It was revealed that bioactive compound producing species of micromonosporae were present in the aquatic habitats of the Sunshine Coast region in Australia.

List of new names and new combinations previously effectively, but not validly, published

The purpose of this announcement is to effect the valid publication of the followingeffectivelypublished new names and new combinations under the procedure described in theBacteriological Code(1990 Revision). Authors and other individuals wishing to have new names and/or combinations included in future lists should sendthree copies of the pertinent reprint or photocopies thereof, or an electronic copy of the published paper, to the IJSEM Editorial Officefor confirmation that all of the other requirements for valid publication have been met.It is also a requirement of IJSEM and the ICSP that authors of new species, new subspecies and new combinations provide evidence that types are deposited in two recognized culture collections in two different countries(i.e. documents certifying deposition and availability of type strains). It should be noted that the date of valid publication of these new names and combinations is the date of publication of this list, not the date of the original publication of the names and combinations. The authors of the new names and combinations are as given below, and these authors' names will be included in the author index of the present issue and in the volume author index. Inclusion of a name on these lists validates the publication of the name and thereby makes it available in bacteriological nomenclature. The inclusion of a name on this list is not to be construed as taxonomic acceptance of the taxon to which the name is applied. Indeed, some of these names may, in time, be shown to be synonyms, or the organisms may be transferred to another genus, thus necessitating the creation of a new combination.