Antimicrobial activity of actinomycetes and characterization of actinomycin-producing strain KRG-1 isolated from Karoo, South Africa

In the present study we reported the antimicrobial activity of actinomycetes isolated from aridic soil sample collected in Karoo, South Africa. Eighty-six actinomycete strains were isolated and purified, out of them thirty-four morphologically different strains were tested for antimicrobial activity. Among 35 isolates, 10 (28.57%) showed both antibacterial and antifungal activity. The ethyl acetate extract of strain KRG-1 showed the strongest antimicrobial activity and therefore was selected for further investigation. The almost complete nucleotide sequence of the 16S rRNA gene as well as distinctive matrix-assisted laser desorption/ionization-time-of-flight/mass spectrometry (MALDI-TOF/MS) profile of whole-cell proteins acquired for strain KRG-1 led to the identification of Streptomyces antibioticus KRG-1 (GenBank accession number: KX827270). The ethyl acetate extract of KRG-1 was fractionated by HPLC method against the most suppressed bacterium Staphylococcus aureus (Newman). LC//MS analysis led to the identification of the active peak that exhibited UV-VIS maxima at 442 nm and the ESI-HRMS spectrum showing the prominent ion clusters for [M-H2O+H]+ at m/z 635.3109 and for [M+Na]+ at m/z 1269.6148. This information could be assigned to chromopeptide lactone antibiotic - actinomycin. Our results suggest that unexplored soils could be an interesting source for exploring antibacterial secondary metabolites.

Septic shock caused by the under-recognized bacterium Eggerthella lenta in a 61-year-old male with a periurethral abscess: a case report

Abstract Eggerthella lenta is a gram-positive anaerobic bacillus that has been associated with life-threatening infections. Bacteremia is always clinically significant and is mostly but not always associated with gastrointestinal disease. We present a unique case of abrupt deterioration and rapid development of septic shock secondary to periurethral abscess caused by E. lenta infection. This case highlights the atypical clinical presentation, risk factors, uncommon source of infection, challenges in therapy, and outcome of this infrequent infection. There is still a gap in the understanding of E. lenta pathogenicity, and more literature is needed to establish clear management recommendations.

Anaerobic biodegradation of benzo(a)pyrene by a novel Cellulosimicrobium cellulans CWS2 isolated from polycyclic aromatic hydrocarbon-contaminated soil

Abstract Cellulosimicrobium cellulans CWS2, a novel strain capable of utilizing benzo(a)pyrene (BaP) as the sole carbon and energy source under nitrate-reducing conditions, was isolated from PAH-contaminated soil. Temperature and pH significantly affected BaP biodegradation, and the strain exhibited enhanced biodegradation ability at temperatures above 30 °C and between pH 7 and 10. The highest BaP removal rate (78.8%) was observed in 13 days when the initial BaP concentration was 10 mg/L, and the strain degraded BaP at constant rate even at a higher concentration (50 mg/L). Metal exposure experimental results illustrated that Cd(II) was the only metal ion that significantly inhibited biodegradation of BaP. The addition of 0.5 and 1.0 g/L glucose enhanced BaP biodegradation, while the addition of low-molecular-weight organic acids with stronger acidity reduced BaP removal rates during co-metabolic biodegradation. The addition of phenanthrene and pyrene, which were degraded to some extent by the strain, showed no distinct effect on BaP biodegradation. Gas chromatography-mass spectrometry (GC-MS) analysis revealed that the five rings of BaP opened, producing compounds with one to four rings which were more bioavailable. Thus, the strain exhibited strong BaP degradation capability and has great potential in the remediation of BaP-/PAH-contaminated environments.

Potential for biocontrol of melanized fungi by actinobacteria isolated from intertidal region of Ilha Do Mel, Paraná, Brazil

Abstract Actinobacteria occur in many environments and have the capacity to produce secondary metabolites with antibiotic potential. Identification and taxonomy of actinobacteria that produce antimicrobial substances is essential for the screening of new compounds, and sequencing of the 16S region of ribosomal DNA (rDNA), which is conserved and present in all bacteria, is an important method of identification. Melanized fungi are free-living organisms, which can also be pathogens of clinical importance. This work aimed to evaluate growth inhibition of melanized fungi by actinobacteria and to identify the latter to the species level. In this study, antimicrobial activity of 13 actinobacterial isolates from the genus Streptomyces was evaluated against seven melanized fungi of the genera Exophiala, Cladosporium, and Rhinocladiella. In all tests, all actinobacterial isolates showed inhibitory activity against all isolates of melanized fungi, and only one actinobacterial isolate had less efficient inhibitory activity. The 16S rDNA region of five previously unidentified actinobacterial isolates from Ilha do Mel, Paraná, Brazil, was sequenced; four of the isolates were identified as Streptomyces globisporus subsp. globisporus, and one isolate was identified as Streptomyces aureus. This work highlights the potential of actinobacteria with antifungal activity and their role in the pursuit of novel antimicrobial substances.

Identification of Vaginal Fluid Using Microbial Signatures / 法医学杂志

OBJECTIVES@#To investigate the specific microbial signatures in vaginal fluid.@*METHODS@#Vaginal fluid （16 samples）, saliva （16 samples）, feces （16 samples）, semen （8 samples）, peripheral blood （8 samples）, urine （5 samples）, and nasal secretion （4 samples） were collected respectively. The 16S rRNA genes of Lactobacillus crispatus, Lactobacillus gasseri, Lactobacillus jensenii, Lactobacillus iners, and Atopobium vaginae were amplified. PCR production was detected via a 3130xl Genetic Analyzer.@*RESULTS@#The detected number of Lactobacillus crispatus, Lactobacillus gasseri, Lactobacillus jensenii, Lactobacillus iners, and Atopobium vaginae were 15, 5, 8, 14, and 3 in all vaginal fluid samples, respectively. Lactobacillus crispatus and Lactobacillus jensenii existed specifically in vaginal fluid.@*CONCLUSIONS@#There is a potential application value to detect Lactobacillus crispatus and Lactobacillus jensenii for the identification of vaginal fluid.

Preliminary Study on Some Actinomycetes and Evaluation of Their Potential Antagonism against Fungal Pathogens.

Aims: Control of microbial pathogens by using antagonistic microorganisms is a promising alternative to chemical fungicides. The objective of the present study was to isolate and characterize soil actinomycetes and to their inhibitory activity against some fungal plant pathogens. Place and Duration of Study: National Park “El Chico”, Hidalgo State, and Laboratory of the Southeast Unit of CIATEJ, Yucatán, México, between June 2010 and May 2011. Methodology: Actinomycete species were isolated from six composite soil samples using microbiological standard procedures. All isolates were phenotypically characterized. Antagonistic isolates were selected according to the inhibitory growing of Fusarium sp. and Candida albicans. Afterwards, a new evaluation for the isolates selected was done against Helminthosporium sp., Curvularia sp., and Aspergillus niger. Actinomycetes were identified performing an analysis of the 16S rDNA gene sequence. Results: 164 actinomycete strains were characterized by morphological and biochemical features. Six of them, inhibited the growth of Fusarium sp. and C. albicans from 5 to 10 mm distance in between the actinomycete´s colony growth border of fungal or yeast. A growing reduction from 50 to 83 % in the in vitro antagonism assays was observed for Helminthosporium sp., Curvularia sp., and Aspergillus niger. Results in disc diffusion assays suggested an inhibitory growing capacity of CACIA-1.46HGO for P. capsici, this behavior could be due to the production of diffusible compounds related to secondary metabolism, hydrolytic enzymes, or both of them. Four antagonistic isolates were identified into Streptomyces genus and one as Microbacterium sp. through 16S rDNA gene sequence. Conclusion: Actinomycetes could be potentially a control tool to prevent several fungal commercial plants diseases. However, in situ isolate evaluations are suggested to be investigated.

Produção de biomassa de erva-cidreira [Lippia alba (Mill. ) N.E.Br. ] sob adubação com composto de capim elefante inoculado e sem inoculação de actinomicetos / Biomass production of Lippia alba (Mill. ) N.E.Br. under fertilization with compost inoculated elephant grass and without inoculation of actinomycetes

A erva-cidreira [Lippia alba (Mill.) N. E. Br.] é uma espécie da família Verbenaceae amplamente utilizada pela população brasileira, devido às propriedades calmante, espasmolítica suave, analgésica, sedativa, ansiolítica e levemente expectorante. Para implantação do experimento foi produzido composto orgânico de capim elefante + esterco, na proporção de 70% de material vegetal e 30% de esterco, sem inoculação e inoculados com os isolados de actinomicetos do gênero Streptomyces: AC16; AC26; AC92 e AC103. Os compostos foram acondicionados em sacos de polietileno contendo 10,0 kg de solo adicionados na proporção equivalente a 20 t ha-1 e foram reaplicados logo após a primeira colheita. As colheitas da parte aérea foram realizadas aos 75 e 165 dias após o transplante. As raízes foram colhidas logo após a segunda colheita. Os tratatamentos com adubação orgânica promoveram aumento médio na produção de biomassa da erva-cidreira de 184, 83, 125, 115 e 122% para biomassa seca da parte aérea (MSPA) na primeira colheita, de MSPA na segunda colheita, biomassa seca total da parte aérea (MSTPA), biomassa seca de raiz (MSR) e biomassa seca total da cultura (MST), respectivamente, quando comparados com o tratamento controle, porém não houve efeito da inoculação de actinomicetos no composto orgânico. Nas condições em que este estudo foi realizado foi possível concluir que a adubação com composto orgânico de capim elefante influenciou positivamente a produção de biomassa seca da L. alba, mas a inoculação dos compostos com actinomicetos não exerceu influência.

L. alba is a species of the family Verbenaceae widely used by the Brazilian population, because of the soothing, gentle antispasmodic, analgesic, expectorant, sedative, anxiolytic and smoothly. For the implementation of the experiment produced organic compound of elephant grass (Pennisetum purpureum Shum.) + manure at 70% plant material and 30% manure, uninoculated and inoculated with the actinomycete Streptomyces genus, AC16, AC26, AC92 and AC103. The compounds were placed in polyethylene bags containing 10.0 kg of soil added in a proportion equivalent to 20 t ha-1 and re-apply after the first harvest. The harvests of the shoots were taken at 75 and 165 days after transplantation. The roots were harvested after the second harvest. Dealing with organic fertilization promoted the average increase in biomass production of lemon grass 184, 83, 125, 115 and 122% for the dry stem biomass (MSPA) in the first harvest, second harvest of MSPA, total shoot biomass (MSTPA), dry biomass of the root (MSR) and the total crop biomass (MST), respectively, compared with the control, but no effect of inoculation of actinomycetes in compost. Under the conditions of this study was conducted, it was concluded that the organic compound fertilizer with elephant grass positively influenced the production of dry biomass of L. alba, but the injection of the compounds of the actinomycetes, without influence.

Comunidades de hongos actinomicetos en tres tipos de vegetación de la Amazonia colombiana: abundancia, morfotipos y el gen 16s ADNr

Communities of Actynomicetes fungy in three vegetation types of the Colombian Amazon: abundance, morphotypes and the 16s rDNA gene. Among soil microorganisms, Actinomycetes play an important role in the sustainability of natural and agricultural systems: decomposition of organic matter; degradation of recalcitrant compounds like lignin; nitrogen fixation; degradation of agricultural chemicals and biological control in plants and animals. We evaluated their diversity in soils under three different vegetation covers (pasture, tropical primary forest and stubble) at two depths in the Southern Colombian Amazon border. We collected five replicates per vegetation type (in each, three samples at 0-20cm and three at 20-30cm; for a total of 30 samples). Abundance and phenotypic diversity were determined by plate counting. Genomic DNA was extracted from the isolates: the 16s rDNA gene was amplified with specific primers, and its genetic diversity was estimated by means of an amplified restriction analysis (ARDRA). Actynomicetes abundance varied with vegetation and depth, possibly reflecting presence of earthworms, macro-fauna and physico-chemical characteristics associated to fertility, as well as organic matter, total bases, and optimal capacity to cationic interchange. Primary forests had the highest diversity. Sixteen morpho-types (six genera) were identified; Streptomyces was the most abundant everywhere. The heterogeneity of ARDRA patterns prevented species identification because of the intra-species variability in sequences of 16s rDNA operons. This community is a biological indicator of landscape alteration and could include new bio-active compounds of pharmaceutical interest. Rev. Biol. Trop. 57 (4): 1119-1139. Epub 2009 December 01.

Los actinomicetos son importantes en la sostenibilidad de sistemas naturales. Su diversidad fue evaluada en suelos de bosque, pastizal y rastrojo, y dos profundidades en el Sur del Trapecio Amazónico Colombiano. Se analizaron suelos de cinco repeticiones por cobertura para un total de 15 unidades. Se tomaron seis muestras en cada unidad y dos profundidades, para un total de 30. Los actinomicetos cultivables se determinaron por recuento en placa, se extrajo ADN, se amplificó el gen ADNr 16s y su diversidad genética se estimó por ARDRA. Hubo diferencias de abundancia entre coberturas y profundidades, relacionadas con la vegetación, presencia de lombrices, macrofauna, altos niveles de materia orgánica, y bases totales. Se obtuvieron valores de diversidad fenotípica similares para las tres coberturas, pero los bosques son más diversos. Se identificaron 16 morfotipos, agrupados en séis géneros, siendo Streptomyces el más abundante. La heterogeneidad de los patrones ARDRA no permitió la asignación de especies, reflejándose variaciones en las secuencias de diferentes operones ADNr 16s en un mismo organismo. Las perturbaciones en la cobertura influyen sobre los actinomicetos, generando cambios en su abundancia y diversidad. Su importancia ecológica permite proponerlos como indicadores biológicos de alteración del paisaje.

Alkalithermophilic actinomycetes in a subtropical area of Jujuy, Argentina / Actinomicetos termoalcalófilos del área subtropical de Jujuy, Argentina

The objective of this study was to examine the alkalithermophilic actinomycete communities in the subtropical environment of Jujuy, Argentina, characterized by sugarcane crops. Laceyella putida, Laceyella sacchari, Thermoactinomyces intermedius, Thermoactinomyces vulgaris and Thermoflavimicrobium dichotomicum were isolated on the media with novobiocin, from sugar cane plants and renewal rhizospheres, and grass and wood soils. Soil pH was almost neutral or lightly alkaline, except for grass soil acidified by lactic liquor. A smaller number of actinomycetes was found on the living plants and bagasse (recently obtained or stored according to the Ritter method) with respect to decomposed leaves on the soil. Thermophilic species of Laceyella, Thermoactinomyces, Thermoflavimicrobium, Saccharomonospora, Streptomyces and Thermononospora were isolated on the media without novobiocin, from composted sugar cane residues. Air captured near composted bagasse piles, contained alkalithermophilic actinomycete spores.

El objetivo de este trabajo fue examinar los actinomicetos termoalcalófilos presentes en el área subtropical de Jujuy, Argentina, caracterizada por el cultivo de la caña de azúcar. Se aislaron en medio con novobiocina las especies Laceyella putida, Laceyella sacchari, Thermoactinomyces intermedius, Thermoactinomyces vulgaris y Thermoflavimicrobium dichotomicum a partir de la rizósfera de plantas y de renuevos de caña de azúcar, así como de suelos de pastura y de monte natural. El pH de los suelos era casi neutro a ligeramente alcalino, excepto en un solo caso en que el suelo estaba acidificado por licor láctico. El número de actinomicetos encontrados sobre los tejidos vivos y en el bagazo recién obtenido o almacenado según el método de Ritter fue pequeño en comparación con el observado sobre las hojas en descomposición. L. sacchari predominó respecto de T. vulgaris. Se aislaron especies termoalcalófilas de Laceyella, Thermoactinomyces, Thermoflavimicrobium, Saccharomonospora, Streptomyces y Thermononospora de los residuos compostados de caña de azúcar utilizando medio sin novobiocina. El aire capturado cerca de pilas de bagazo en compostaje contenía esporos de estos organismos.

Phosphate solubilizing actinomycetes in the estuarine environment: an inventory.

Sediment samples were collected from different stations of the Vellar estuary for isolation of total actinomycetes and phosphate solubilizing actinomycetes. Phosphatase activity in the sediments was also investigated Consistently a higher number of actinomycetes, phosphate solubilizing actinomycetes and phosphatase activity were recorded from the clay sediments than the sandy sediments at all the stations. In all, 7 strains showed positive phosphatase activity. Among them, one strain PS-3 exhibited good activity and was further investigated for optimum phosphorus solubilization at different pH (6, 6.5, 7, 7.5 and 8) and incubation (1st day to 20th day) periods. The solubilizing activity was maximum at the pH 7 and an incubation period of 13 days was required for an appreciable quantity of phosphorus to be leached into the medium. Based on the chemotaxonomical and conventional methods of identification, the strain PS-3 has been tentatively identified as Streptomyces galbus. The present study indicates that phosphatase enzyme and S. galbus along with other actinomycetes species would play a major role in solubilizing the phosphate in the estuarine ecosystem and increasing the soluble phosphate concentration thereby enhancing the productivity

Studies on L-asparaginase enzyme of actinomycetes isolated from estuarine fishes.

Actinomycetes were isolated from different organs viz. skin, gills and gut contents of three species of fishes viz. Mugil cephalus (Linnaeus, 1758), Chanos chanos (Forskal, 1775) and Etroplus suratensis (Bloch, 1780) using three different media from the Vellar estuary, situated along the southeast coast of India. Among the three fishes, M. cephalus harboured highest number of actinomycetes population in all the three body parts examined followed by C. chanos and E. suratensis. Out of the three body parts of all fishes, gut contents had highest actinomycetes population followed by gills and skin. Among the three media used for isolation of actinomycetes, Kuster's agar medium was found to be suitable than the starch casein agar and glucose asparagine agar media. Out of the 40 strains isolated, only six strains (LA-2, LA-8, LA-15, LA-20, LA-29 and LA-35) showed significant L-asparagianse activity and were taken up for further studies. Impact of various physical and chemical factors such as pH, temperature, sodium chloride concentration, carbon sources and amino acids on the growth of actinomycetes and L-asparaginase activity was also studied. Optimum growth and enzyme activity was noticed under pH 7 to 8, temperature 37 degrees C, 1-2% sodium chloride concentration, sucrose as carbon source and without any amino acids. Analysis of the cell components of the isolated strains has revealed the wall type-I (the wall type-I is typical for the genus Streptomyces) and the strains were micromorphologically similar to the genus Streptomyces. Hence, the morphological, physiological and biochemical along with the micromorphological results obtained for the L-asparaginase producing strains were compared and the strains were tentatively identified as Streptomyces aureofasciculus (LA-2), S. chattanoogenesis (LA-8), S. hawaiiensis (LA-15), S. orientalis (LA-20), S. canus (LA-29) and S. olivoviridis (LA-35).

A Case of Bacteremia by Atopobium rimae in a Patient with Liver Cirrhosis / 대한진단검사의학회지

Atopobium rimae, previously Lactobacillus rimae, is a strictly anaerobic, non-spore forming grampositive rod which was frequently isolated from odontogenic infection. We report a case of A. rimae bacteremia. A 47-yr-old man with liver cirrhosis was admitted to the hospital via emergency room due to fever and chill. His abdominal and pelvic computed tomography revealed a small abscess near the left adrenal gland. Three sets of blood cultures were taken and non-spore forming, grampositive rods were detected in all anaerobic vials. This isolate grew small nonhemolytic, gray-white translucent colonies on Brucella blood agar and was obligatory anaerobic on air-tolerance test. This organism was negative for catalase, indole, nitrate-reduction and beta-lactamase and failed to identify by Vitek ANI card (bioMerieux, France). 16S rRNA sequences of this showed 99.8% homology of the published sequence of A. rimae (GenBank accession number AF292371). Aspirates of periadrenal abscess grew Escherichia coli and Peptostreptococcus micros. He was treated with metronidazole and imipenem and follow-up cultures of blood were negative at days 4 and 10. To our knowledge, this is the first report of bacteremia of A. rimae.