Nonomuraea corallina sp. nov., isolated from coastal sediment in Samila Beach, Thailand: insights into secondary metabolite synthesis as anticancer potential.

A novel marine actinomycete, designated strain MCN248T, was isolated from the coastal sediment in Songkhla Province, Thailand. Based on the 16S rRNA gene sequences, the new isolate was closely related to Nonomuraea harbinensis DSM45887T (99.2%) and Nonomuraea ferruginea DSM43553T (98.6%). Phylogenetic analyzes based on the 16S rRNA gene sequences showed that strain MCN248T was clustered with Nonomuraea harbinensis DSM45887T and Nonomuraea ferruginea DSM43553T. However, the digital DNA-DNA hybridization analyzes presented a low relatedness of 40.2% between strain MCN248T and the above closely related strains. This strain contained meso-diaminopimelic acid. The acyl type of the peptidoglycan was acetyl, and mycolic acids were absent. The major menaquinones were MK-9(H2) and MK-9(H4). The whole cell sugars consisted of madurose, ribose, mannose, and glucose. Diphosphatidylglycerol, hydroxyl-phosphatidylethanolamine, phosphatidylethanolamine, phosphatidylinositol, and phosphatidylglycerol were detected as the major phospholipids. The predominant cellular fatty acids were iso-C16:0 (40.4%), 10-methyl-C17:0 (22.1%), and C17:1ω8c (10.9%). The DNA G + C content of the genomic DNA was 71.7%. With in silico analyzes, the antiSMASH platform uncovered a diverse 29 secondary metabolite biosynthesis arsenal, including non-ribosomal peptide synthetase (NRPS) and polyketide synthase (PKS) of strain MCN248T, with a high prevalence of gene cluster encoding pathways for the production of anticancer and cytotoxic compounds. Consistently, the crude extract could inhibit colorectal HCT-116 cancer cells at a final concentration of 50 µg/mL. Based on the polyphasic approach, strain MCN248 was designated as a novel species of the genus Nonomuraea, for which the name Nonomuraea corallina sp. nov. is proposed. The type strain of the type species is MCN248T (=NBRC115966T = TBRC17110T).

Rhizohabitans arisaemae gen. nov., sp. nov., a novel actinomycete of the family Streptosporangiaceae.

An actinomycete strain K14-0274T was isolated from the root of Arisaema thunbergii Blume subsp. urashima (H. Hara) H. Ohashi et J. Murata collected in Japan. The results of phylogenetic analysis based on the 16S rRNA gene sequence indicated thatK14-0274T could be distinguished from the members of all known genera, although it represented a member of the family Streptosporangiaceae. K14-0274T produced sporangium-like spherical vesicles with spores on white aerial mycelia. MK-9 (H4) and MK-9 (H6) were the major menaquinones. The whole-cell hydrolysates contained madurose, glucose, mannose, rhamnose and ribose. The cell-wall amino acids comprise l-alanine, d-alanine, d-glutamic acid and meso-diaminopimelic acid. The N-acyl type of muramic acid was acetyl. Mycolic acids were not detected. Phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylinositol and phosphatidylinositolmannoside were detected. The predominant fatty acids were iso-C16 : 0, 10-methyl-C18 : 0 and C16 : 0. The G+C content of the genomic DNA was 69.7 mol%. On the basis of morphological, phylogenetic and chemotaxonomic characteristics, strain K14-0427T represents a novel genus in the family Streptosporangiaceae, for which the name Rhizohabitans arisaemae gen. nov., sp. nov. is proposed. The type strain is K14-0247T (=NBRC 114594T =TBRC 12948T).

Amycolatopsis iheyensis sp. nov., isolated from soil on Iheya Island, Japan.

A novel actinomycete, designated strain OK19-0408T, was isolated from soil collected on Iheya island, Okinawa prefecture, Japan. Using the polyphasic taxonomic approach, comparing 16S rRNA gene sequences, the new isolate was found to be most closely related to Amycolatopsis vancoresmycina JCM12675T (98.71 %). Phylogenetic analyses using 16S rRNA sequences indicated that strain OK19-0408T was clustered with Amycolatopsis australiensis JCM15587T. However, digital DNA-DNA hybridization analyses indicated a low relatedness, in the range of 33.9-34.7 %, between strain OK19-0408T and these closely related strains. Strain OK19-0408T contained meso-diaminopimelic acid and whole-cell sugars consisting of arabinose and galactose. The acyl type of the peptidoglycan was acetyl and mycolic acids were absent in strain OK19-0408T. The major menaquinone was MK-9(H4) and hydroxy-phosphatidylethanolamine was detected as the predominant phospholipid. The predominant cellular fatty acid was iso-C16 : 0. The DNA G+C content of the genomic DNA was 71.5 mol%. Based on the polyphasic approach, strain OK19-0408T represents a novel species of the genus Amycolatopsis, for which the name Amycolatopsis iheyensis sp. nov. is proposed. The type strain of the type species is OK19-0408T (=NBRC115671T=TBRC16040T).

Mycelial differentiation linked avermectin production in Streptomyces avermitilis studied with Raman imaging.

Streptomyces avermitilis is a gram-positive bacterium that undergoes complex physiological and morphological differentiation during its life cycle, which has implications in secondary metabolite production. Avermectin, produced by S. avermitilis, is widely used as an anthelmintic and insecticidal agent. In this study, we have applied Raman microspectroscopic imaging to elucidate the correlation between production of avermectin and the morphological differentiation in S. avermitilis. We demonstrate distinctive variations in the localization of secondary metabolites at various stages of morphological differentiation. Under solid culture, avermectin was detected in the mycelia formed at the later stages of morphological differentiation (e.g., spore-bearing mycelium and spiral spore chains), but not in the early-stage substrate mycelium. On the contrary, under liquid culture condition, avermectin was found concentrated in the mycelial pellet formed at the early MII stage of differentiation. Furthermore, the chemical profiles of the mycelia were substantially different depending on the culture condition. Raman spectra corresponding to proteins, lipids, and cytochrome were observed in the mycelia irrespective of the stage of morphological differentiation, however, carotenoid was observed under solid culture condition particularly in spore-bearing mycelium and spiral spore chains. KEY POINTS: • Avermectin production is regulated during mycelial differentiation • Liquid and solid culture conditions affects mycelial differentiation • Raman microspectroscopic analysis reveals localization profiles of avermectin.

Bovine abortion and necrotic placentitis by Aspergillus terreus.

A 31-month-old Japanese Black cow (Bos taurus) aborted at 5 months of gestation with no clinical symptoms. Histopathological examination of the placenta and fetus revealed severe necrotic placentitis associated with numerous irregular degenerative fungi and inflammatory cells. Regular filamentous fungi were also detected, without inflammatory response in the fetal digestive and respiratory organs. Both fungi had aleurioconidia and septa in the placenta and fetal organs and immunohistochemically stained with antibodies against Aspergillus spp. Aspergillus terreus was isolated from the fetal lung and abomasal contents as confirmed using mycological and molecular methods. This is the first immunohistochemical, morphological, and molecular identification of A. terreus in bovine placenta and aborted fetuses.

Swine abortion caused by Candida parapsilosis.

In July 2020, a sow in a breeding herd in the Chiba Prefecture, Japan, suffered abortion. A necropsy revealed pale pulmonary foci scattered in the two fetuses. Histologically, multifocal pulmonary necrosis was detected with numerous yeasts. The yeast was positively stained using the periodic acid-Schiff reaction and Grocott's silver stain. Molecular identification indicated that the yeast was Candida parapsilosis. In conclusion, our results suggested that C. parapsilosis caused multifocal necrotizing pneumonia in the two fetuses. This study is the first report of a swine abortion with C. parapsilosis infection.

Exploring natural microbial resources for the discovery of anti-malarial compounds.

Microorganisms in nature are highly diverse biological resources, which can be explored for drug discovery. Some countries including Brazil, Columbia, Indonesia, China, and Mexico, which are blessed with geographical uniqueness with diverse climates and display remarkable megabiodiversity, potentially provide microorganismal resources for such exploitation. In this review, as an example of drug discovery campaigns against tropical parasitic diseases utilizing microorganisms from such a megabiodiversity country, we summarize our past and on-going activities toward discovery of new antimalarials. The program was held in a bilateral collaboration between multiple Indonesian and Japanese research groups. In order to develop a new platform of drug discovery utilizing Indonesian bioresources under an international collaborative scheme, we aimed at: 1) establishment of an Indonesian microbial depository, 2) development of robust enzyme-based and cell-based screening systems, and 3) technology transfer necessary for screening, purification, and identification of antimalarial compounds from microbial culture broths. We collected, characterized, and deposited Indonesian microbes. We morphologically and genetically characterized fungi and actinomycetes strains isolated from 5 different locations representing 3 Indonesian geographical areas, and validated genetic diversity of microbes. Enzyme-based screening was developed against two validated mitochondrial enzymes from Plasmodium falciparum, dihydroorotate dehydrogenase and malate:quinone oxidoreductase, while cell-based proliferation assay was developed using the erythrocytic stage parasite of 3D7 strain. More than 17 thousands microbial culture extracts were subjected to the enzyme- and cell-based screening. Representative anti-malarial compounds discovered in this campaign are discussed, including a few isolated compounds that have been identified for the first time as anti-malarial compounds. Our antimalarial discovery campaign validated the Indonesian microbial library as a powerful resource for drug discovery. We also discuss critical needs for selection criteria for hits at each stage of screening and hit deconvolution such as preliminary extraction test for the initial profiling of the active compounds and dereplication techniques to minimize repetitive discovery of known compounds.

Gentisyl alcohol and homogentisic acid: Plasmodium falciparum dihydroorotate dehydrogenase inhibitors isolated from fungi.

Two Indonesian fungi Aspergillus assiutensis BioMCC-f.T.7495 and Penicillium pedernalense BioMCC-f.T.5350 along with a Japanese fungus Hypomyces pseudocorticiicola FKI-9008 have been found to produce gentisyl alcohol (1), which inhibits Plasmodium falciparum dihydroorotate dehydrogenase (PfDHODH) with an IC50 value of 3.4 µM. Another Indonesian fungus, Penicillium citrinum BioMCC-f.T.6730, produced an analog of 1, homogentisic acid (4), which also inhibits PfDHODH with an IC50 value of 47.6 µM.

Taxonomic and Metabolite Diversities of Moss-Associated Actinobacteria from Thailand.

Actinobacteria are a group of ecologically important bacteria capable of producing diverse bioactive compounds. However, much remains unknown about the taxonomic and metabolic diversities of actinobacteria from many geographic regions and ecological niches. In this study, we report the isolation of actinobacteria from moss and moss-associated rhizosphere soils in Thailand. Among the 89 isolates analyzed for their bioactivities, 86 strains produced indole-3-acetic acid (IAA, ranging from 0.04 to 59.12 mg/L); 42 strains produced hydroxamate type of siderophore; 35 strains produced catecholate type of siderophore; 21 strains solubilized tricalcium phosphate; and many strains exhibited antagonistic activities against one to several of the seven selected plant, animal, and human pathogens. Overall, actinobacteria from the rhizosphere soil of mosses showed greater abilities to produce IAA and siderophores and to solubilize tricalcium phosphate than those from mosses. Among these 89 isolates, 37 were analyzed for their 16S rRNA gene sequences, which revealed their diverse phylogenetic distributions among seven genera, Streptomyces, Micromonospora, Nocardia, Actinoplanes, Saccharothrix, Streptosporangium, and Cryptosporangium. Furthermore, gas chromatography-mass spectrometry analyses of ethyl acetate crude extracts of three selected isolates with inhibitory effects against a methicillin-resistant Staphylococcus aureus strain revealed diverse metabolites with known antimicrobial activities. Together, our results demonstrate that actinobacteria from mosses in Thailand are taxonomically diverse and capable of producing a range of metabolites with plant-growth-promoting and microbial pathogen-inhibiting potentials.

Detection of Penicillin G Produced by Penicillium chrysogenum with Raman Microspectroscopy and Multivariate Curve Resolution-Alternating Least-Squares Methods.

Raman microspectroscopy is a minimally invasive technique that can identify molecules without labeling. In this study, we demonstrate the detection of penicillin G inside Penicillium chrysogenum KF425 fungal cells. Raman spectra acquired from the fungal cells had highly overlapped spectroscopic signatures and hence were analyzed with multivariate curve resolution by alternating least-squares (MCR-ALS) to extract the spectra of individual molecular constituents. In addition to detecting spatial distribution of multiple constituents such as proteins and lipids inside the fungal body, we could also observe the subcellular localization of penicillin G. This methodology has the potential to be employed in screening the production of bioactive compounds by microorganisms.

Microbial inhibitors active against Plasmodium falciparum dihydroorotate dehydrogenase derived from an Indonesian soil fungus, Talaromyces pinophilus BioMCC-f.T.3979.

An Indonesian soil fungus, Talaromyces pinophilus BioMCC-f.T.3979 was cultured to find novel scaffolds of Plasmodium falciparum dihydroorotate dehydrogenase (PfDHODH) inhibitors. We obtained altenusin (1), which inhibits PfDHODH, with an IC50 value of 5.9 µM, along with other metabolites: mitorubrinol (2) and mitorubrinic acid (3). Compounds 1 and 2 inhibited PfDHODH but displayed no activity against the human orthologue. They also inhibited P. falciparum 3D7 cell growth in vitro. Compound 3 showed little PfDHODH inhibitory activity or cell growth inhibitory activity.

Streptomyces mimosae sp. nov., an endophytic actinomycete isolated from the root of Mimosa pudica in Thailand.

An endophytic actinomycete, strain 3MP-10T, isolated from the root of Mimosa pudica was taxonomically studied based upon polyphasic approaches. This strain formed spiral spore chains on aerial mycelia. ll-Diaminopimelic acid, glucose and ribose were found in the whole-cell hydrolysates. It belonged to the genus Streptomyces and was closely related to Streptomyces zhaozhouensis DSM 42101T (98.9 %) and Streptomyces sedi JCM 16909T (98.6 %) based on 16S rRNA gene sequence analysis results. The major menaquinones were MK-10(H8), MK-10(H6) and MK-9(H8). The predominant cellular fatty acids were iso-C16 : 0, anteiso-C15 : 0 and anteiso-C17 : 0. The detected phospholipids were diphosphatidylglycerol, phosphatidylinositol mannoside, phosphatidylinositol, phosphatidylethanolamine and phosphatidylglycerol. Strain 3MP-10T had a genome size of 7.2 Mb with a genome G+C content of 73.4 mol%. Results of in silico genome-based similarity analysis revealed ANIb values of 84.94 and 84.77 %, ANIm values of 88.01 and 87.92 %, and dDDH values of 29.9 and 29.6 % when compared with S. zhaozhouensis DSM 42101T and S. sedi JCM 16909T, respectively. Based on the polyphasic approach, digital DNA-DNA relatedness and average nucleotide identity, we propose that the novel actinomycete represents a novel species, Streptomyces mimosae, with type strain 3MP-10T (=JCM 33328T=TISTR 2646T).

Micromonospora pelagivivens sp. nov., a new species of the genus Micromonospora isolated from deep-sea sediment in Japan.

A novel marine actinomycete, designated strain KJ-029T, was isolated from a marine sediment sample (water depth of 226 m) in Kagoshima, Japan. 16S rRNA gene sequence analysis revealed that the new isolate was most closely related to Micromonospora craniellae LHW 63014T (99.3 % similarity). Phylogenetic analyses of the genus Micromonospora based on 16S rRNA gene sequences showed that strain KJ-029T was clustered with Micromonospora craniellae LHW 63014T and Micromonospora endophytica 202201T. However, digital DNA-DNA hybridization analyses presented low levels of relatedness in the range of 24.8-32.9 % between strain KJ-029T and the above closely related strains. The novel strain contained meso-diaminopimelic acid and 3-OH-diaminopimelic acid, d-glutamic acid, glycine and d-alanine in the cell-wall peptidoglycan. The acyl type of the peptidoglycan was glycolyl and mycolic acids were absent. The major menaquinone was MK-9(H4). The whole-cell sugars consisted of glucose, mannose, xylose and ribose. Phosphatidylethanolamine was detected as the major phospholipid and corresponded to phospholipid type II. The predominant cellular fatty acid was iso-C16 : 0. The DNA G+C content of the genomic DNA was 71.5 mol%. Based on the present polyphasic study, strain KJ-029T represents a novel species of the genus Micromonospora, for which the name Micromonospora pelagivivens sp. nov. is proposed. The type strain is KJ-029T (=NBRC 113519T=TBRC 9233T).

Fodinicola acaciae sp. nov., an Endophytic Actinomycete Isolated from the Roots of Acacia mangium Willd. and Its Genome Analysis.

A novel endophytic actinomycete strain GKU 173T isolated from the roots of Acacia mangium Willd. showed potential plant growth promoting (PGP) activity. Phylogenetic analysis, based on 16S rRNA gene, indicated that strain GKU 173T was the most closely related to Fodinicola feengrottensis HKI 0501T-the only species in the genus Fodinicola. Morphology and chemotaxonomy of strain GKU 173T indicated that it belongs to the genus Fodinicola by having meso-diaminopimelic acid in the cell wall and xylose as the characteristic cell-wall sugars. The cellular fatty acid profile mainly comprised iso-C16:0, anteiso-C17:0, iso-C18:0, and iso-C17:0. The major menaquinones were MK-9(H4), MK-9(H6), and MK-9(H8). The main polar phospholipids contained diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE), and phosphatidylinositol (PI). Genome analysis signified DNA G+C content of 67.81 mol%. The level of digital DNA-DNA relatedness between strain GKU 173T and the type strain was 21.30%. On the basis of polyphasic characteristics, strain GKU 173T clearly represents a novel species of the genus Fodinicola, for which the name Fodinicola acaciae sp. nov. (= TBRC 10620T = NBRC 114213T) is proposed. Furthermore, genome analysis of both strains suggested that members of the genus Fodinicola are promising sources of beneficial PGP-actinomycetes and novel secondary metabolites.

Amycolatopsis pithecelloba sp. nov., a novel actinomycete isolated from roots of Pithecellobium dulce in Thailand.

An actinomycete strain RM579T isolated from roots of Pithecellobium dulce in Thailand was studied using the polyphasic taxonomic approach. The results of comparative 16S rRNA gene sequence and phylogenetic analysis showed that strain RM579T belonged to the family Pseudonocardiaceae and it was most closely related to members of the genera Amycolatopsis (≤94.5% sequence similarity) and Haloechinothrix (≤93.4% sequence similarity). A phylogenetic tree constructed by neighbor-joining method indicated that strain RM579T was positioned within the clade of the genus Amycolatopsis and formed a monophyletic cluster with Amycolatopsis taiwanensis 0345M-7T, Amycolatopsis pigmentata TT00-43T and Amycolatopsis helveola TT99-32T. Strain RM579T formed white aerial mycelium and yellowish-brown substrate mycelium that fragments into rod-shaped elements. Morphological features and chemotaxonomic characteristics of strain RM579T were consistent with those of the genus Amycolatopsis. The cell wall of strain RM579T contained meso-diaminopimelic acid. Arabinose, galactose, mannose, and ribose were detected as whole-cell sugars. Mycolic acids were absent. The acyl type of the muramic acid in the cell wall was N-acetyl. Diphosphatidylglycerol, hydroxyl-phosphatidylethanolamine, phosphatidylinositol, and an unidentified phospholipid were detected as polar lipids. The major cellular fatty acids (>10%) were iso-C16:0, iso-C16:0 2-OH, and C16:1 cis9. The resultant data indicated that strain RM579T should be classified as representative of a novel species in the genus Amycolatopsis, for which the name Amycolatopsis pithecelloba sp. nov. is proposed. The type strain is RM579T (=TBRC 1849T =NBRC 106096T).

Amycolatopsis eburnea sp. nov., an actinomycete associated with arbuscular mycorrhizal fungal spores.

A novel actinomycete, designated strain GLM-1T, was isolated from arbuscular mycorrhizal fungal spores from Funneliformis mosseae RYA08, collected from Aquilaria crassna Pierre ex Lec. rhizosphere soil in Klaeng, Rayong Province, Thailand. Morphological characteristics of this strain included long chains of rod-like cells and squarish elements. The cell-wall composition of this novel isolate contained meso-diaminopimelic acid. The whole-cell diagnostic sugars were arabinose and galactose. The predominant menaquinone was MK-9(H4). The major fatty acids were iso-C16 : 0 and iso-C15 : 0. Only phosphatidylethanolamine was detected as a polar lipid. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain GLM-1T was closely related to Amycolatopsis rhabdoformis SB026T (99.11 %) with a low DNA-DNA hybridization value of 22.6-34.7 %. Genome sequencing revealed a genome size of 10 Mbp. There were obvious distinctions in the average nucleotide identity values between stain GLM-1T and its closely related strains at around 86-93 % (ANIb) and 89-94 % (ANIm). The digital DNA-DNA hybridization values between strain GLM-1T and type strains of phylogenetically related species were 34-55 %. The G+C content of the genomic DNA was 71.8 mol%. Based on these data, strain GLM-1T is considered to represent a novel species of the genus Amycolatopsis, for which the name Amycolatopsiseburnea sp. nov. is proposed. The type strain is GLM-1T (=TBRC 9315T=NBRC 113658T).

Amycolatopsis suaedae sp. nov., an endophytic actinomycete isolated from Suaeda maritima roots.

An actinomycete strain, designated 8-3EHSuT, was isolated from surface-sterilised roots of Suaeda maritima, collected from Petchburi province, Thailand. Taxonomic position of strain 8-3EHSuT was studied using a polyphasic approach. Phylogenetic determination based on the 16S rRNA gene sequence similarity showed that strain 8-3EHSuT belongs to the genus Amycolatopsis, with the highest sequence similarity to Amycolatopsis jiangsuensis KLBMP 1262T (96.9 %). The colony of strain 8-3EHSuT was yellowish white. Long straight mycelium breaking down into fragments were observed. Growth occurred at temperatures 15-45 °C and at pH 6.0-10.0. The strain contained meso-diaminopimelic acid, arabinose, galactose and mannose in whole-organism hydrolysates. The predominant menaquinone was MK-9(H4). The major fatty acids were C16 : 0, iso-C16 : 0 and iso-C15 : 0. Polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, hydroxyphosphatidylethanolamine, two unknown amino lipids and an unknown lipid. The G+C content of genomic DNA was 71.8 mol%. A phylogenetic tree based on 16S rRNA sequences showed that the strain 8-3EHSuT formed a distinct evolutionary linage within the genus Amycolatopsis. Based on analysis results of physiological, biochemical and chemotaxonomic data, strain 8-3EHSuT represents a novel species of the genus Amycolatopsis, for which the name Amycolatopsis suaedae sp. nov. is proposed. The type strain is 8-3EHSuT (=TBRC 8488T=NBRC 113449T).

Gordonia oryzae sp. nov., isolated from rice plant stems (Oryza sativa L.).

A novel endophytic actinomycete, designated strain RS15-1ST, was isolated from surface-sterilized stems of Oryza sativa L. collected from Sisaket province, Thailand. The colony of strain was strong orange, catalase-positive and oxidase-negative. Growth occurred at a temperature range of 17-37 °C, at pH 4.0-9.0 and in the presence of 0-13 % (w/v) NaCl. Phylogenetic analyses based on the 16S rRNA sequences showed that strain RS15-1ST belonged to the genus Gordonia and was closely related to Gordonia polyisoprenivorans DSM 44302T (98.8 %) and Gordonia rhizosphera DSM 44383T (98.4 %). The major cellular fatty acids were C16 : 0, C18 : 0 10-methyl (tbsa), C16 : 1ω7c/C16 : 1ω6c and C18 : 1ω9c. The menaquinones were MK-9(H2) and MK-8(H2). Strain RS15-1ST contained meso-diaminopimelic acid, arabinose, galactose, mannose and ribose in whole-cell hydrolysates. The polar lipids of the strain were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol mannosides, an unidentified polar lipid and two unidentified phospholipids. The DNA G+C content was 66.3 mol%. In silico DNA-DNA hybridization of strain RS15-1ST showed 48.3 and 20.5 % relatedness to its closest neighbours, Gordonia polyisoprenivorans DSM 44302T and Gordonia rhizosphera DSM 44383T, respectively. Based on data of genotypic, phenotypic, phylogenetic and chemotaxonomic analysis, strain RS15-1ST represents a novel species of the genus Gordonia, for which the name Gordonia oryzae sp. nov. is proposed. The type strain is RS15-1ST (=TBRC 8485T=NBRC 113446T).

Nonomuraea suaedae sp. nov., isolated from rhizosphere soil of Suaeda maritima (L.) Dumort.

A polyphasic approach was used to identify the novel actinomycete, strain 10-20SHSuT, isolated from the rhizosphere of the mangrove associated plants Suaeda maritima collected from Phetchaburi Province, Thailand. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the organism belonged to the phylogenetic cluster of the genus Nonomuraea and was most closely related to Nonomuraea soli YIM 120770T (98.1% sequence similarity), Nonomuraea endophytica YIM 65601T (97.3%) and Nonomuraea candida HMC10T (97.3%). The strain formed an extensively branched substrate and aerial mycelia. The whole-cell hydrolysates contained meso-diaminopimelic acid as the diagnostic diamino acid, with galactose, glucose, madurose, mannose and ribose as the whole-cell sugars. The polar lipids were diphosphatidylglycerol, hydroxy-phosphatidylethanolamine, hydroxy-phosphatidylmonomethylethanolamine, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol mannosides, phosphatidylinositol, phosphotidylmethylethanolamine, two unidentified sugar containing phosphoaminolipids and an unidentified phospholipid. MK-9(H4) was a major menaquinone of the organism. The predominant cellular fatty acids were iso-C16:0, C17:0 and 10-methyl-C17:0. The G + C content of the genomic DNA was 71.9 mol%. On the basis of phenotypic characteristics, DNA-DNA relatedness and phylogenetic distinctiveness, strain 10-20SHSuT represents a novel species of the genus Nonomuraea, for which the name Nonomuraea suaedae sp. nov. is proposed. The type strain is 10-20SHSuT (=TBRC 8487T =NBRC 113448T).