Antrihabitans stalactiti gen. nov., sp. nov., a new member of the family Nocardiaceae isolated from a cave.

Two Gram-stain-positive, strictly aerobic, non-spore-forming actinobacterial strains, designated YC2-7T and YC5-17, were isolated from the Yongcheondonggul (larva cave) in Jeju, Republic of Korea and their taxonomic ranks were examined by a polyphasic approach. The 16S rRNA gene tree showed that the novel isolates occupied an independent position separated from recognized genera of the family Nocardiaceae. In the 92 core gene-based phylogenomic analysis, strain YC2-7T was loosely associated with the type strain of Aldersonia kummingensis with 66.2 % average amino acid identity. The 16S rRNA gene sequence simairity between the isolate and members of the family Nocardiaceae was below 96.7 %. The cell-wall peptidoglycan was meso-diaminopimelic acid as a diagnostic diamino acid. Whole-cell sugars consisted of arabinose, galactose and glucose. The predominant menaquinone was MK-8(H4, ω-cycl). The major polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol and phosphatidylinositol mannoside. The cellular fatty acids consisted mainly of saturated and unsaturated components with small amounts of tuberculostearic acid. Mycolic acids of 52-58 carbon atoms were present. The DNA G+C content of the genome was 63.8 mol%. On the basis of combination of morphological and chemotaxonomic differences, in addition to phylogenetic distinctness, the novel isolates are considered to constitute members of a novel species of a new genus in the family Nocardiaceae, for which the name Antrihabitans stalactiti gen. nov., sp. nov. is proposed. The type strain is YC2-7T (=KACC 19965T=DSM 108733T).

Screening and characterization of marine actinomycetes from the northern Oman Sea sediments for cytotoxic and antimicrobial activity

A total of 168 actinomycete colonies were isolated from 14 sediment samples of the northern parts of the Oman Sea and were screened for cytotoxic and antimicrobial activity. Among four media and two treatments, the glucose arginine agar medium (18%) and heat treatment (28.3%) showed maximum isolation rate of actinomycetes. Preliminary characterization revealed that the members of Streptomycetaceae were widely distributed (66%) in the most of the sampling stations followed by Micromonosporaceae (14%), Nocardiaceae (6%), and Pseudonocardiaceae (4%), respectively. Approximately, 23.8% of the isolates inhibited the growth of at least one of the microbial test strains, while the majority of them belonged to the Streptomycetaceae family. Minimum inhibitory concentrations of the ethyl acetate culture extracts of the five most putative isolates varied from 64 μg/mL against Micrococcus luteus and Candida albicans to 1 mg/mL against Aspergillus niger. These extracts showed significant cytotoxic activity at18.74-193.5 μg/mL on the human breast (MCF7), colon (HCT 116), and liver (HepG2) tumor cell lines while exhibited less or no cytotoxicity on the normal cell line (HUVEC). Interestingly, IFSRI 193 extract selectively inhibited the growth of HCT 116 cell line and gram-positive bacteria. 16S rRNA gene sequencing revealed that the potent isolates have 97 to 99% similarity with S. chartreusis, S. cacaoi, S. sampsonii, S. qinglanensis, and S. diastaticus. These results suggested that the five Streptomyces strains could be considered candidates for discovering the antitumor antibiotics

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Mumiamicin: Structure and bioactivity of a new furan fatty acid from Mumia sp. YSP-2-79.

A new antibiotic, designated mumiamicin, was isolated from the cultured broth of the rare actinomycete strain, Mumia sp. YSP-2-79, by Diaion HP-20, silica gel and ODS column chromatography, followed by HPLC purification. The chemical structure of mumiamicin was elucidated as a new furan fatty acid by nuclear magnetic resonance and mass spectrometry. Mumiamicin showed antimicrobial activity and antioxidative activity.

Production of a new glycolipid biosurfactant from marine Nocardiopsis lucentensis MSA04 in solid-state cultivation.

Considering the need of potential biosurfactant producers and economic production processes using industrial waste, the present study aims to develop solid-state culture (SSC) of a marine actinobacterium for biosurfactant production. A potential biosurfactant producer Nocardiopsis lucentensis MSA04 was isolated from the marine sponge Dendrilla nigra. Among the substrates screened, wheat bran increased the production significantly (E(24) 25%) followed by oil seed cake and industrial waste such as tannery pretreated sludge, treated molasses (distillery waste) and pretreated molasses. Enhanced biosurfactant production was achieved under SSC conditions using kerosene as carbon source, beef extract as nitrogen source and wheat bran as substrate. The maximum production of biosurfactant by MSA04 occurred at a C/N ratio of 0.5 envisaging that a higher amount of nitrogen source is required by the strain compared to that of the carbon source. The kerosene and beef extract interactively increase the production and a stable production was attained with the influence of both factors independently. A significant interactive influence of secondary control factors such as copper sulfate and inoculum size was validated in response surface methods-based experiments. The surface active compound produced by MSA04 was characterized as glycolipid with a hydrophobic non-polar hydrocarbon chain (nonanoic acid methyl ester) and hydrophilic sugar, 3-acetyl 2,5 dimethyl furan. In conclusion, the strain N. lucentensis MSA04 was a potential source of glycolipid biosurfactant, could be used for the development of bioremediation processes in the marine environment.

Nocardiopsis aegyptia sp. nov., isolated from marine sediment.

An actinomycete, strain SNG49(T), was isolated from marine sediment of Abu Qir Bay, on the western seashore of Alexandria, Egypt. The bacterium was aerobic and Gram-positive. It produced beige to light-yellow aerial mycelium, brown substrate mycelium and straight to flexuous hyphae, but no specific spore chains. 16S rDNA sequence analysis and chemotaxonomic markers were consistent with classification of strain SNG49(T) in the genus Nocardiopsis, i.e. meso-diaminopimelic acid; no diagnostic sugars; phosphatidylcholine, phosphatidylmethylethanolamine, phosphatidylinositol, phosphatidylglycerol and diphosphatidylglycerol as polar lipids; menaquinones of the MK-10 series from MK-10(H(0)) to MK-10(H(8)); and iso/anteiso-branched and 10-methyl-branched fatty acids, the principal fatty acids being anteiso-17 : 0 and tuberculostearic acid. Nocardiopsis lucentensis and Nocardiopsis alba are the phylogenetic neighbours of strain SNG49(T), respectively showing 98.8 and 98.7 % 16S rRNA gene sequence similarity; however, moderate DNA-DNA reassociation values between these two species and strain SNG49(T) (44 and 60 %, respectively) showed that strain SNG49(T) could be clearly separated from them. These data, together with distinct physiological traits, led to the conclusion that this isolate represents a novel species within the genus Nocardiopsis, for which the name Nocardiopsis aegyptia is proposed. The type strain is SNG49(T) (=DSM 44442(T)=NRRL B-24244(T)).

Nocardioides aquiterrae sp. nov., isolated from groundwater in Korea.

A bacterial strain, GW-9T, which was isolated from groundwater in Korea, was subjected to a polyphasic taxonomic study using phenotypic characterization and phylogenetic and genetic methods. Phylogenetic analysis based on 16S rDNA sequences showed that strain GW-9T forms an evolutionary lineage within the radiation enclosing Nocardioides species and, in particular, a coherent cluster with Nocardioides pyridinolyticus. The cell-wall peptidoglycan type of strain GW-9T was based on LL-diaminopimelic acid as the diamino acid, indicating wall chemotype I. The predominant menaquinone was MK-8(H4). Strain GW-9T had a cellular fatty acid profile containing straight-chain, branched, unsaturated and 10-methyl fatty acids. The major fatty acid was iso-C(16:0). The DNA G+C content of strain GW-9T was 73 mol%. The 16S rDNA of strain GW-9T was 99.2% similar to that of the type strain of Nocardioides pyridinolyticus and 94.9-96.0% similar to sequences of the type strains of other Nocardioides species. Differences in phenotypic characteristics and genetic distinctiveness indicate that strain GW-9T is separate from previously described Nocardioides species. Therefore, on the basis of the data presented, a novel species of the genus Nocardioides, Nocardioides aquiterrae sp. nov., is proposed. The type strain is strain GW-9T (=KCCM 41647T=JCM 11813T).

Aeromicrobium marinum sp. nov., an abundant pelagic bacterium isolated from the German Wadden Sea.

An obligately salt-dependent Gram-positive bacterium, designated strain T2(T), was isolated from surface waters of the German Wadden Sea. The organism exhibited optimum growth at salt concentrations similar to that of sea water. On the basis of phenotypic, chemotaxonomic and phylogenetic differences, it is concluded that strain T2(T) (=DSM 15272(T)=LMG 21768(T)) is the first marine species of the genus Aeromicrobium to be identified, for which the name Aeromicrobium marinum is proposed. It is also the first described marine bacterium within the family Nocardioidaceae. Strain T2(T) is a rod-shaped, aerobic, heterotrophic bacterium containing LL-diaminopimelic acid in the peptidoglycan and MK-9(H(4)) as the major menaquinone. The bacterium is characterized by high proportions of the fatty acids palmitic acid, oleic acid, tuberculostearic acid and hydroxypalmitic acid. DNA-DNA hybridization analysis showed the marine bacterium to display 29.1 % relatedness with Aeromicrobium fastidiosum DSM 10552(T) and 44.4 % relatedness with Aeromicrobium erythreum DSM 8599(T). A. marinum was demonstrated to be an abundant member of the pelagic bacterial community in the German Wadden Sea since it represented about 1 % of the total bacterial population as revealed by dot-blot hybridization and most-probable-number counts.

Patterns of antimicrobial activities from soil actinomycetes isolated under different conditions of pH and salinity.

AIMS: To evaluate the patterns of the production of antimicrobial compounds by diverse collection of actinomycetes isolated from different geographies under alternative conditions of pH and salinity in the media. METHODS AND RESULTS: Actinomycetes were grouped based on their method of isolation and their phenotype diversity was determined by total fatty acid analysis. A total of 335 representative isolates, including 235 Streptomyces species and 100 actinomycetes from other taxa, were screened for the production of antimicrobial activities against a panel of bacteria, filamentous fungi and yeasts, including some of clinical relevance. Production of antimicrobial activities was detected in 230 strains. In the case of the genus Streptomyces, 181 antimicrobial activities (77% of the tested isolates) were recorded. The activities observed among the other actinomycetes taxa were lower (49% of the tested isolates). CONCLUSIONS: The results of this study support the idea that species of actinomycetes isolated in alternative selective conditions of pH and salinity present a significant capacity to produce compounds with antibacterial or antifungal activity. The best group of isolates in terms of production of active secondary metabolites was the one isolated in saline conditions. SIGNIFICANCE AND IMPACT OF THE STUDY: The results demonstrate that these actinomycetes strains isolated in alternative selective conditions of pH and salinity and collected from diverse geographical locations present a significant capacity to produce compounds with antibacterial or antifungal activity.

Characterization of JP-7 jet fuel degradation by the bacterium Nocardioides luteus strain BAFB.

In the fall of 1996, numerous bacteria capable of degrading JP-7 jet fuel were isolated from soil collected at Beale Air Force Base in northern California. The most prevalent organism, identified as Nocardioides luteus by16s rRNA sequencing (MIDI Labs, Inc.), was selected for further analysis. Analysis of JP-7 following inoculation with N. luteus demonstrated degradation of the C(11) alkane component of the fuel. Growth rates of N. luteus were determined with alkanes of various lengths as the sole carbon and energy source. The organism grew best on shorter length alkanes (C(8) and C(10)). Growth was measurably slower on C(11), and minimal on C(12), C(13), and C(14).

Molecular detection, isolation, and physiological characterization of functionally dominant phenol-degrading bacteria in activated sludge.

DNA was isolated from phenol-digesting activated sludge, and partial fragments of the 16S ribosomal DNA (rDNA) and the gene encoding the largest subunit of multicomponent phenol hydroxylase (LmPH) were amplified by PCR. An analysis of the amplified fragments by temperature gradient gel electrophoresis (TGGE) demonstrated that two major 16S rDNA bands (bands R2 and R3) and two major LmPH gene bands (bands P2 and P3) appeared after the activated sludge became acclimated to phenol. The nucleotide sequences of these major bands were determined. In parallel, bacteria were isolated from the activated sludge by direct plating or by plating after enrichment either in batch cultures or in a chemostat culture. The bacteria isolated were classified into 27 distinct groups by a repetitive extragenic palindromic sequence PCR analysis. The partial nucleotide sequences of 16S rDNAs and LmPH genes of members of these 27 groups were then determined. A comparison of these nucleotide sequences with the sequences of the major TGGE bands indicated that the major bacterial populations, R2 and R3, possessed major LmPH genes P2 and P3, respectively. The dominant populations could be isolated either by direct plating or by chemostat culture enrichment but not by batch culture enrichment. One of the dominant strains (R3) which contained a novel type of LmPH (P3), was closely related to Valivorax paradoxus, and the result of a kinetic analysis of its phenol-oxygenating activity suggested that this strain was the principal phenol digester in the activated sludge.

Cultivation of a nocardioform acid-fast chemoautotrophic bacterium from armadillo tissues infected with Mycobacterium leprae.

A nocardioform bacterium was isolated from the spleen tissue of an armadillo infected with M. leprae and easily propagated in pure culture in mineral salt medium supplemented with only simple C and N sources (e.g., liquid paraffin, tetradecane, ammonium salts, urea, asparagine, gelatin, xanthin, hypoxanthin etc.). Complex organic substances, e.g., tyrosin, casein, peptone, meat extract, egg proteins, serum, blood, yeast extract as well as medium 199, did not support the growth of this organism. Microscopically, the organism consisted of acid-fast, long, slender rods which originated from long, fragmented hyphae, or sporulating mycelial tufts; it was acid-fast (at less than 4.0% H2SO4) which was pyridine-susceptible. It produced DOPA-oxidase and Catalase and was lysozyme resistant; this grew best under reduced O2 tension, at pH 7.0 to 8.0 and 28 degrees C. Serologically, it appeared to be only weakly related to the prototype human multibacillary leprosy-derived (reference) nocardioform strain, Nocardia brasiliensis and N. caviae, but was variably related to several mycobacteria strains.

[Isolation of Actinomycetales from the soil of Kazakhstan on selective media with antibiotics]. / Vydelenie aktinomitsetov iz pochv Kazakhstana na selektivnykh sredakh s antibiotikami.

About 3000 actinomycetes were isolated from various soil samples collected in 11 regions of Kazakhstan. 62.7 per cent of them proved to be antagonists. For isolation of the strains, selective media supplemented with antibiotics were used. Kanamycin promoted growth of Actinomadura and Nocardia. Rubomycin promoted growth of Actinomadura. Tavromycetin and roseofungin were used as selective agents for the first time. Tavromycetin favoured isolation of Actinomadura and Nocardia. Roseofungin favoured isolation of Actinomadura. Light chestnut and serozemic soils were the most rich in antagonists (67.1 and 61.3 per cent, respectively) while saline and chestnut soils were the poorest in antagonists (32.2 and 30.6 per cent, respectively). Actinomadura were more frequent in light-chestnut light-loamy and serozemic soils. Half of the antibiotics isolated in the form of concentrates were identified with the known antibiotics or classified as belonging to various groups. A culture producing a novel antibiotic was isolated.

Catheter-related bacteremia caused by Oerskovia turbata.

A case of Broviac catheter-related bacteremia in a 3-year-old boy infected with Oerskovia turbata is discussed. The blood cultures of the patient remained positive despite antibiotic therapy, and only with catheter removal was his blood sterilized. The microbiology and antimicrobial susceptibilities of this organism are described.

Actinomadura pelletieri mycetoma from the Transvaal. A case report.

The osteophilic red grain mycetoma due to Actinomadura pelletieri is rare in southern Africa. This report describes an elderly patient with extensive bone involvement in which lymphatic spread to the inguinal lymph nodes had occurred. The diagnosis and management are discussed.

Meningitis caused by Gordona aurantiaca (Rhodococcus aurantiacus).

In a case of hairy cell leukemia, Gordona aurantiaca (Rhodococcus aurantiacus) was isolated from cerebrospinal fluid as the pathogen responsible for lethal infection of the central nervous system. The pathogen had been isolated previously from one case of pulmonary infection process only.

Occurrence of Rhodococcus coprophilus and associated actinomycetes in feces, sewage, and freshwater.

Freshwater, sewage, and fecal samples from various sources were examined for Rhodococcus coprophilus, associated actinomycetes, Escherichia coli, and fecal streptococci. Rhodococcus coprophilus was isolated consistently from feces of farm animals, poultry reared in proximity to farm animals, freshwater, and wastewater polluted with animal fecal wastes. It was not isolated from samples of human feces. The ratio of R. coprophilus total actinomycetes was higher in feces from cattle, sheep, ducks, and geese than in specimens from pigs, horses, and fowl. In samples from two freshwater streams polluted by fecal material from farm animals, the ratios of R. copropilus to total actinomycetes were similar to those found in fecal specimens from cattle and sheep. Ratios of fecal coliform to fecal streptococci could not distinguish between fresh human and animal fecal samples and, furthermore, were not reflected in the stream waters polluted by animal fecal material. R. coprophilus has potential in water and dairy bacteriology as a specific indicator organism of fecal pollution due to farm animal wastes.

Survey of human pathogenic actinomycetes and fungi in soil from Rome and other Italian areas.

As part of a study sponsored by the Ministry of Health of Italy, a research program on pathogenic actinomycetes, keratinophilic and pathogenic fungi in soil was carried out. Two hundred soil samples, collected from different areas of the city of Rome, Calabria, Emilia Romagna, Latium, Apulia, Sardinia, Sicily, Tuscany and Umbria, were examined by several techniques to detect the widest possible variety of pathogenic actinomycetes and fungi. Seven isolates of Nocardia asteroides, four of Actinomadura madurae and one of Nocardiopsis dassonvillei were isolated for the first time from soil in Italy. In addition, numerous isolates of Petriellidium boydii, Aspergillus fumigatus, A. flavus, A. niger and keratinophilic fungi of the genera Microsporum, Trichophyton and Chrysosporium were also recovered.

Oerskovia species: rare opportunistic pathogens.

The second documented instance of opportunistic infection by member of the genus Oerskovia is reported. There is some evidence to suggest that this group of bacteria, which is extensively distributed in the soil, may be more closely associated with man than has hitherto been supposed.