Pattama Pittayakhajonwut

Micromonospora sediminicola sp. nov., isolated from marine sediment

An actinomycete strain, designated strain SH2-13(T), was isolated from a marine sediment sample collected from the Andaman Sea of Thailand. Applying a polyphasic approach, the isolate was identified as a member of the genus Micromonospora using morphological and chemotaxonomic characteristics, including the presence of meso-diaminopimelic acid in the peptidoglycan. Whole-cell sugars were arabinose, galactose, glucose, rhamnose, ribose and xylose. Diagnostic polar lipids were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannosides and phosphoglycolipids. The major menaquinones were MK-10(H(2)), MK-10(H(4)) and MK-10(H(6)). 16S rRNA gene sequence analysis revealed similarity to Micromonospora marina JSM1-1(T) (99.1u200a%), Micromonospora coxensis 2-30-b(28)(T) (99.1u200a%), Micromonospora aurantiaca DSM 43813(T) (98.8u200a%) and Micromonospora chalcea DSM 43026(T) (98.7u200a%). However, a combination of DNA-DNA hybridization results and phenotypic properties indicated that strain SH2-13(T) (u200a=u200aNBRC 107934(T)u200a=u200aBCC 45601(T)) should be classified as the type strain of a novel species, with the proposed name Micromonospora sediminicola sp. nov.

Micromonospora fluostatini sp. nov., isolated from marine sediment

The novel actinomycete strain PWB-003T, which produced fluostatins B and C antibiotics, was isolated from nearshore sediment collected from Panwa Cape, Phuket Province, Thailand. Data from the present polyphasic study indicated that strain PWB-003T represented a member of the genus Micromonospora. It produced single spores on substrate mycelia and contained meso-diaminopimelic acid in the cell-wall peptidoglycan. Whole-cell hydrolysate contained ribose, xylose, arabinose, mannose and glucose. The predominant menaquinone was MK-10 (H4). Cellular fatty acids comprised C18u2009:u20091ω9c, iso-C16u2009:u20090, anteiso-C17u2009:u20090, iso-C15u2009:u20090 and iso-C17u2009:u20090. On the basis of 16S rRNA gene sequence similarity analysis, the novel strain was closely related to Micromonospora eburnea LK2-10T (99.38u2009%), Micromonospora chaiyaphumensis MC5-1T (99.16u2009%), Micromonospora yangpuensis FXJ6.011T (98.97u2009%), Micromonospora echinaurantiaca DSM 43904T (98.97u2009%), Micromonospora pallida DSM 43817T (98.97u2009%), Micromonospora sagamiensis DSM 43912T and Micromonospora auratinigra JCM 12357T (both 98.97u2009%). The G+C content of the DNA was 74.5u200amol%. DNA-DNA relatedness values among strain PWB-003T and related type strains ranged from 11.3u2009±u20091.3 to 38.8u2009±u20091.1u2009%. On the basis of these observations, strain PWB-003T could be distinguished from its closely related type strains and is considered to represent a novel species of the genus Micromonospora, for which the name Micromonospora fluostatini sp. nov. (type strain PWB-003Tu2009=u2009JCM 30529Tu2009=u2009PCU 341Tu2009=u2009TISTR 2345T) is proposed.

Nonomuraea rhodomycinica sp. nov., isolated from peat swamp forest soil

The taxonomic position of an actinomycete, strain NR4-ASC07T, isolated from a soil sample collected from Sirindhorn peat swamp forest, Narathiwat Province, Thailand, was clarified using a polyphasic approach. On the basis of morphological and chemotaxonomic characteristics, it was classified among the members of the genus Nonomuraea. It produced tightly closed spiral spore chains on aerial mycelium as well as forming a pseudosporangium. Whole-cell hydrolysates contained meso-diaminopimelic acid, glucose, ribose, madurose and mannose. The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, hydroxyphosphatidylethanolamine, lyso-phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannosides, unknown ninhydrin-positive phosphoglycolipids and unknown glycolipid. Menaquiones were MK-9(H4), MK-9(H0), MK-9(H2), MK-10(H4) and MK-9(H6). Predominant cellular fatty acids were iso-C16u200a:u200a0, C17u200a:u200a0 10-methyl, C16u200a:u200a0, C17u200a:u200a1ω8c, C16u200a:u200a0 2-OH and iso-C15u200a:u200a0. The phylogenetic tree reconstructed on the basis of 16S rRNA gene sequences showed that the strain fell within the clade containing Nonomuraea muscovyensis FMN03T, Nonomuraea roseoviolacea subsp. roseoviolaceaNBRC 14098T and Nonomuraea roseoviolacea subsp. carminataNBRC 15903T. The DNA-DNA relatedness and phenotypic data supported that strain NR4-ASC07T was clearly distinguished from the closely related species and represents a novel species of the genus Nonomuraea for which the name Nonomuraea rhodomycinica sp. nov. is proposed. The type strain is NR4-ASC07T (=NBRC 112327T=TISTR 2465T).

Amycolatopsis stemonae sp. nov., isolated from Thai medicinal plant.

A novel actinomycete, strain ST1-08T, was isolated from stem of Stemona sp. in Thailand. The taxonomic position of this isolate was determined by using polyphasic approach. Strain ST1-08T contained meso-diaminopimelic acid in cell wall peptidoglycan and contained arabinose and galactose as the diagnostic sugars of the whole cell hydrolysate that were typical properties of the members in the genus Amycolatopsis. It grew at 15-40 oC, pH 6-9 and on 5 % (w/v) NaCl. Gelatin liquefaction, starch hydrolysis and skim milk peptonization were positive. This strain utilized L-arabinose, D-glucose, glycerol, myo-inositol, D-mannitol and L-rhamnose. The predominant menaquinone was MK-9(H4) and the major cellular fatty acids were iso-C16:0 and iso-C15:0. The major polar lipids were diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE), hydroxyl-phosphatidylethanolamine (OH-PE), phosphatidylinositol (PI) and phosphatidylglycerol (PG). The 16S rRNA gene sequence analysis exhibited that the strain was closely related to Amycolatopsis pretoriensis JCM 12673T (98.99 %) and A. lexingtonensis JCM 12672T (98.87 %). The DNA G+C content was 71.2 %. The DNA-DNA relatedness values among strain ST1-08T, A. pretoriensis JCM 12673T and A. lexingtonensis JCM 12672T were lower than 70%, the cutoff level for assigning strains to the same species. On the basis of phenotypic and genotypic characteristics, the strain ST1-08T represents a novel species of the genus Amycolatopsis, for which the name Amycolatopsis stemonae (Type strain ST1-08T = JCM 30050T =PCU 339T = TISTR 2278T) is proposed.A novel actinomycete, strain ST1-08T, was isolated from the stem of Stemona sp. in Thailand. The taxonomic position of this isolate was determined by using a polyphasic approach. Strain ST1-08T contained meso-diaminopimelic acid in the cell-wall peptidoglycan, and arabinose and galactose as diagnostic sugars of the whole-cell hydrolysate, which are typical properties of members of the genus Amycolatopsis. Strain ST1-08T grew at 15-40u2009°C, pHu20096-9 and on 5u200a% (w/v) NaCl. Gelatin liquefaction, starch hydrolysis and skimmed milk peptonization were positive. The strain utilized l-arabinose, d-glucose, glycerol, myo-inositol, d-mannitol and l-rhamnose. The predominant menaquinone was MK-9(H4) and the major cellular fatty acids were iso-C16u200a:u200a0 and iso-C15u200a:u200a0.The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, hydroxyl-phosphatidylethanolamine, phosphatidylinositol and phosphatidylglycerol. The 16S rRNA gene sequence analysis revealed that the strain was closely related to Amycolatopsis pretoriensis JCM 12673T (98.99u200a%) and Amycolatopsis lexingtonensis JCM 12672T (98.87u200a%). The DNA G+C content of strain ST1-08T was 71.2u200amol%. The DNA-DNA relatedness values among strain ST1-08T, A. pretoriensis JCM 12673T and A. lexingtonensis JCM 12672T were lower than 70u200a%, the cut-off level for assigning strains to the same species. On the basis of phenotypic and genotypic characteristics, strain ST1-08T represents a novel species of the genus Amycolatopsis, for which the name Amycolatopsis stemonae is proposed. The type strain is ST1-08T(u2009=u2009JCM 30050Tu2009=u2009PCU 339Tu2009=u2009TISTR 2278T).

Streptomyces verrucosisporus sp. nov., isolated from marine sediments

Five actinomycete isolates, CPB1-1T, CPB2-10, BM1-4, CPB3-1 and CPB1-18, belonging to the genus Streptomyces were isolated from marine sediments collected from Chumphon Province, Thailand. They produced open loops of warty spore chains on aerial mycelia. ll-Diaminopimelic acid, glucose and ribose were found in their whole-cell hydrolysates. Polar lipids found were diphosphatidylglycerol, phosphatidylethanolamine, lysophosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol and phosphatidylinositol mannoside. Menaquinones were MK-9(H6), MK-9(H8), MK-10(H6) and MK-10(H8). Major cellular fatty acids were anteiso-C15u2009:u20090, anteiso-C17u2009:u20090 and iso-C16u2009:u20090. The taxonomic position of the strains was described using a polyphasic approach. blastn analysis of the 16S rRNA gene sequence revealed that these five strains exhibited the highest similarities with Streptomyces mangrovicola GY1 (99.0u2009%), Streptomyces fenghuangensisGIMN4.003T (98.6u2009%), Streptomyces barkulensisRC 1831T (98.5u2009%) and Streptomyces radiopugnans R97T (98.3u2009%). However, their phenotypic characteristics and 16S rRNA gene sequences as well as DNA-DNA relatedness differentiated these five strains from the other species of the genus Streptomyces. Here, we propose the novel actinomycetes all being representatives of the same novel species, Streptomyces verrucosisporus, with type strain CPB1-1T (=JCM 18519T=PCU 343T=TISTR 2344T).

Graphisins A and B from the Lichen Graphis tetralocularis

Crude extracts of the lichen Graphis tetralocularis exhibited antimycobacterial activity, with minimum inhibitory concentration (MIC) values in a range of 100–200 μg mL–1. Chemical investigation of the broth led to the isolation of acremonidin E (1) and graphisins A (2) and B (3). Acremonidin E (1) displayed antitubercular activity with MIC values of 50 μg mL–1 and showed cytotoxicity against BC, KB, and NCI-H187 cell lines with IC50 values of 12.79–27.12 μg mL–1, whereas graphisins A (2) and B (3) were inactive to these tests.

Micromonospora globbae sp. nov., an endophytic actinomycete isolated from roots of Globba winitii C. H. Wright

A novel endophytic actinomycete, strain WPS1-2T, isolated from a root of Globba winitii C. H. Wright, was characterized taxonomically by using a polyphasic approach. Strain WPS1-2T exhibited identical characteristics to the members of the genus Micromonospora. Single spores were observed directly on substrate mycelia. The cell-wall peptidoglycan of the strain contained meso-diaminopimelic acid and 3-OH-meso-diaminopimelic acid. Whole-cell hydrolysates contained glucose, ribose, arabinose and xylose. The predominant menaquinones were MK-10(H8) and MK-10(H10). The major cellular fatty acids consisted of iso-C15u200a:u200a0, iso-C16u200a:u200a0 and anteiso-C15u200a:u200a0. According to the 16S rRNA gene sequence of the strain, WPS1-2T showed highest similarity to Micromonospora costi CS1-12T (99.02u200a%). Phylogenetic analysis of the gyrase subunit B (gyrB) gene indicated that the strain was related to M. costi CS1-12T. The DNA G+Cu2009content was 73.7u2009mol%. The strain could be distinguished from closely related type strains by using a combination of morphological, chemotaxonomic, physiological and biochemical data together with DNA-DNA relatedness values. Based on these observations, strain WPS1-2T is considered to represent a novel species of the genus Micromonospora, for which the name Micromonospora globbae sp. nov. is proposed. The type strain is WPS1-2T (=KCTC 39787T=NBRC 112325T=TISTR 2405T).

Antimicrobial substances from the rare actinomycete Nonomuraea rhodomycinica NR4-ASC07T

Abstract Nonomuraea rhodomycinica NR4-ASC07T is a rare actinomycete isolated from soil in Sirindhorn peat swamp forest. The crude extract of its culture broth exhibited antimicrobial and anticancer against diverse human pathogens and cancer cells. The chemical investigation of the crude extract led to the isolation of two new metabolites named nonomuric acid (1) and 3-hydroxy deoxydaunorubicinol aglycone (2), along with two known bioactive compounds [ε-rhodomycinone (3) and 7-deoxy-13-dihydrocarminomycinone (4)]. Compounds 1 and 3 showed antimalarial activity with the half maximal inhibitory concentration (IC50) of 8.00 and 8.88 μg mL−1, respectively. Compound 4 inhibited growth of Mycobacterium tuberculosis and Bacillus cereus at the minimum inhibitory concentrations of 50.0 and 12.50 μg mL−1, respectively. Every compound exhibited cytotoxicity against cancer cells tested at IC50 ≥ 6.34 μg mL−1. These finding are the first report of bioactive metabolites produced by strain NR4-ASC07T, suggesting that rare actinomycetes are yet promising sources for novel drug discovery.