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Abstract Rhodococcus is a pathogen that is known to cause infections in animals and humans, mainly in cases of immunocompromised patients. A case of a pediatric cancer patient suffering from a bloodstream infection caused by Rhodococcus corynebacterioides was described in this work. Gram positive rods were isolated from blood cultures. The target bacterium was identified using a combination of biochemical tests, the MALDI-TOF mass spectrometry technique, and the analysis of the 16S rRNA sequence. Moreover, an antimicrobial susceptibility test was performed using the E-test. The isolated bacterium was identified as R. corynebacterioides. The 3-year-old patient was successfully treated with vancomycin and meropenem. This is the first published report of R. corynebacterioides in a pediatric patient diagnosed with retinoblastoma that developed a bloodstream infection. R. corynebacterioides should be considered among the opportunistic infectious agents affecting pediatric cancer patients.

Resumen Rhodococcus es un patógeno conocido por causar infecciones en animales y humanos, principalmente en pacientes inmunocomprometidos. En este trabajo se describe el caso de un paciente pediátrico con cáncer que presentó una infección del torrente sanguíneo causada por Rhodococcus corynebacterioides. A partir de hemocultivos, se aislaron bacilos gram positivos. La bacteria diana fue identificada usando una combinación de pruebas bioquímicas, por espectrometría de masas MALDI-TOF y por el análisis de la secuencia del gen 16S ARNr. Además, se realizó una prueba de sensibilidad a los antimicrobianos utilizando E-test. La cepa bacteriana se identificó como R. corynebacterioides. El paciente, de 3 años, fue tratado con vancomicina y meropenem, exitosamente. Este es el primer reporte de R. corynebacterioides como agente causal de una infección del torrente sanguíneo en un paciente pediátrico con retinoblastoma. R. corynebacterioides debe considerarse entre los agentes infecciosos oportunistas que afectan a los pacientes pediátricos con cáncer.

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Rhodococcus is a pathogen that is known to cause infections in animals and humans, mainly in cases of immunocompromised patients. A case of a pediatric cancer patient suffering from a bloodstream infection caused by Rhodococcus corynebacterioides was described in this work. Gram positive rods were isolated from blood cultures. The target bacterium was identified using a combination of biochemical tests, the MALDI-TOF mass spectrometry technique, and the analysis of the 16S rRNA sequence. Moreover, an antimicrobial susceptibility test was performed using the E-test. The isolated bacterium was identified as R. corynebacterioides. The 3-year-old patient was successfully treated with vancomycin and meropenem. This is the first published report of R. corynebacterioides in a pediatric patient diagnosed with retinoblastoma that developed a bloodstream infection. R. corynebacterioides should be considered among the opportunistic infectious agents affecting pediatric cancer patients.

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A microbial fuel cell (MFC), a novel technology, is a biochemical catalyzer system that can convert the chemical energy of materials to bioelectric energy. This system can serve as a unique device for the treatment of wastewater. Based on this knowledge, we decided to study the bioenergy production ability of Actinomycete and microbial isolates in industrial glass factory wastewater as the decomposers of organic materials in this wastewater and the generation of Voltage and current in two batches and fed-batch conditions. At the most favorable condition maximum of 1.08 V (current 3.66 mA and power density 2.88 mW/m2), 81.2% chemical oxygen demand was obtained for a fed-batch system. Also, the outcomes of MFC's essential parameters, for example, pH and TDS, were studied before and after the performance of MFC. The results showed a significant decrease after the operation of the MFC. To realize which Actinomycete were the most powerful bioelectric microorganism, the growth curve and electricity performance of three kinds of Actinomycete was selected. Results showed that the C2 would be more potent because its Voltage of 0.224 V and current of 1.187 mA possessed by it would result in an excellent power density of 141.42 mW/m2.

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Octocorals are among the most prolific sources of biologically active compounds. A significant part of their specialized metabolites richness is linked to the abundance of their associated microbiota. Consequently, research on the bioprospecting potential of microorganisms associated with these marine invertebrates has gained much interest. Here, we describe the draft genome of Gordonia hongkongensis strain EUFUS-Z928 isolated from the octocoral Eunicea fusca. The genome was assembled de novo from short-read whole-genome sequencing data. Additionally, functional annotation of predicted genes was performed using the RAST tool kit, including genome mining for specialized metabolite biosynthetic gene clusters using the antiSMASH v6.0 tool. The genome sequence data of G. hongkongensis EUFUS-Z928 can provide information for further analysis of the potential biotechnological use of this microorganism and guide the characterization of other related actinobacterial isolates. Likewise, this information increases the analytical capacity for studying the genus Gordonia.

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An alkaliphilic actinobacterium, designated VN6-2T, was isolated from marine sediment collected from Valparaíso Bay, Chile. Strain VN6-2T formed yellowish-white branched substrate mycelium without fragmentation. Aerial mycelium was well developed, forming wavy or spiral spore chains. Strain VN6-2T exhibited a 16S rRNA gene sequence similarity of 93.9 % to Salinactinospora qingdaonensis CXB832T, 93.7 % to Murinocardiopsis flavida 14-Be-013T, and 93.7 % to Lipingzhangella halophila 14-Be-013T. Genome sequencing revealed a genome size of 5.9 Mb and an in silico G+C content of 69.3 mol%. Both of the phylogenetic analyses based on 16S rRNA gene sequences and the up-to-date bacterial core gene sequences revealed that strain VN6-2T formed a distinct monophyletic clade within the family Nocardiopsaceae. Chemotaxonomic assessment of strain VN6-2T showed that the major fatty acids were iso-C16 : 0, anteiso-C17 : 0 and 10-methyl-C18 : 0, and the predominant respiratory quinones were MK-9, MK-9(H2) and MK-9(H4). Whole-cell hydrolysates contained meso-diaminopimelic acid as the cell-wall diamino acid, and ribose and xylose as the diagnostic sugars. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, aminophospholipids, glycolipid and phospholipid. Based on the results of this polyphasic study, a novel genus, Spiractinospora gen. nov., is proposed within the family Nocardiopsaceae and the type species Spiractinospora alimapuensis gen. nov., sp. nov. The type strain is VN6-2T (CECT 30026T, CCUG 66258T). On the basis of the phylogenetic results herein, we also propose that Nocardiopsis arvandica and Nocardiopsis litoralis are later heterotypic synonyms of Nocardiopsis sinuspersici and Nocardiopsis kunsanensis, respectively, for which emended descriptions are given.

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Three new 3-hydroxy-N-methyl-2-oxindole (1 and 2) and 4-hydroxy-pyran-2-one (3) derivatives, along with the known 3-hydroxy-N-methyl-2-oxindole (4) and 6-methoxy-N-methylisatin (5) were isolated from a marine Salinispora arenicola strain from sediments of the St. Peter and St. Paul Archipelago, Brazil. The structures of the new compounds were elucidated by a combination of spectroscopic (1D and 2D NMR and HR-ESIMS) data, including single-crystal X-ray diffraction analysis for 2 and 3. Compounds 1 to 5 were assayed for their antimicrobial properties, but only 4 and 5 were active against Enterococcus faecalis with MIC value of 15.6 µg/mL.

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A novel Gram-positive, non-motile, non-spore-forming and aerobic bacterium, designated strain VA37-3T, was isolated from a marine sediment sample collected at 19.2 m water depth from Valparaíso bay, Chile. Strain VA37-3T exhibits 97.6 % 16S rRNA gene sequence similarity to Corynebacterium marinum D7015T, 96.4 % to Corynebacterium humireducens MFC-5T and 96 % to Corynebacterium testudinoris M935/96/4T; and a rpoB gene sequence similarity of 85.1 % to Corynebacterium pollutisoli VMS11T, both analyses suggesting that strain VA37-3T represents a novel species of Corynebacterium. Physiological testing indicated that strain VA37-3T requires artificial sea water or sodium-supplemented media for growth, representing the first obligate marine actinomycete of the genus Corynebacterium. The genome of the proposed new species, along with the type strains of its most closely related species were sequenced and characterized. In silico genome-based similarity analyses revealed an ANIb of 72.8 % (C. marinum D7015T), ANIm of 85.0 % (Corynebacterium mustelae DSM 45274T), tetra of 0.90 (Corynebacterium callunae DSM 20147T) and ggdc of 24.7 % (Corynebacterium kutscheri DSM 20755T) when compared with the closest related strains. The genomic DNA G+C content of strain VA37-3T was 57.0 %. Chemotaxonomic assessment of strain VN6-2T showed the major fatty acids were C18 : 1ω9c and C16 : 0. Menaquinones predominantly consisted of MK-8(II-H2). Polar lipids consisted of diphosphatidylglycerol, glycolipids, phosphatidylglycerol, phosphoglycolipid and phosphatidylinositol. Mycolic acids also were present. Overall, the results from phylogenetic, phenotypic and genomic analyses confirmed that strain VA37-3T represents a novel species of the genus Corynebacterium, for which the name Corynebacterium alimapuense sp. nov. is proposed, with VA37-3T as the type strain (=CCUG 69366T=NCIMB 15118T).

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Background: Poly(DL-lactic acid), or PDLLA, is a biodegradable polymer that can be hydrolyzed by various types of enzymes. The protease produced by Actinomadura keratinilytica strain T16-1 was previously reported to have PDLLA depolymerase activity. However, few studies have reported on PDLLA-degrading enzyme production by bacteria. Therefore, the aims of this study were to determine a suitable immobilization material for PDLLA-degrading enzyme production and optimize PDLLA-degrading enzyme production by using immobilized A. keratinilytica strain T16-1 under various fermentation process conditions in a stirrer fermenter. Results: Among the tested immobilization materials, a scrub pad was the best immobilizer, giving an enzyme activity of 30.03 U/mL in a shake-flask scale. The maximum enzyme activity was obtained at aeration 0.25 vvm, agitation 170 rpm, 45°C, and 48 h of cultivation time. Under these conditions, a PDLLA-degrading enzyme production of 766.33 U/mL with 15.97 U/mL·h productivity was observed using batch fermentation in a 5-L stirrer fermenter. Increased enzyme activity and productivity were observed in repeated-batch (942.67 U/mL and 19.64 U/mL·h) and continuous fermentation (796.43 U/mL and 16.58 U/mL·h) at a dilution rate of 0.013/h. Scaled-up production of the enzyme in a 10-L stirrer bioreactor using the optimized conditions showed a maximum enzyme activity of 578.67 U/mL and a productivity of 12.06 U/mL·h. Conclusions: This research successfully scaled-up the enzyme production to 5 and 10 L in a stirrer fermenter and is helpful for many applications of poly(lactic acid).

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Streptomyces sp. H-KF8 is an actinobacterial strain isolated from marine sediments of a Chilean Patagonian fjord. Morphological characterization together with antibacterial activity was assessed in various culture media, revealing a carbon-source dependent activity mainly against Gram-positive bacteria (S. aureus and L. monocytogenes). Genome mining of this antibacterial-producing bacterium revealed the presence of 26 biosynthetic gene clusters (BGCs) for secondary metabolites, where among them, 81% have low similarities with known BGCs. In addition, a genomic search in Streptomyces sp. H-KF8 unveiled the presence of a wide variety of genetic determinants related to heavy metal resistance (49 genes), oxidative stress (69 genes) and antibiotic resistance (97 genes). This study revealed that the marine-derived Streptomyces sp. H-KF8 bacterium has the capability to tolerate a diverse set of heavy metals such as copper, cobalt, mercury, chromate and nickel; as well as the highly toxic tellurite, a feature first time described for Streptomyces. In addition, Streptomyces sp. H-KF8 possesses a major resistance towards oxidative stress, in comparison to the soil reference strain Streptomyces violaceoruber A3(2). Moreover, Streptomyces sp. H-KF8 showed resistance to 88% of the antibiotics tested, indicating overall, a strong response to several abiotic stressors. The combination of these biological traits confirms the metabolic versatility of Streptomyces sp. H-KF8, a genetically well-prepared microorganism with the ability to confront the dynamics of the fjord-unique marine environment.

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ABSTRACT Present study aim to evaluate the antimicrobial, antioxidant and cytotoxic potential of crude extract of Marine Streptomyces carpaticus MK-01 isolated from seawater collected from Daejeong-cost of Jeju Island. About 24 actinomycetes strains were isolated and subjected to morphological and molecular analysis that confirmed the isolate as S. carpaticus MK-01. Crude ethyl acetate extract of MK-01 strain showed extensive antibacterial activity against Gram-positive fish pathogenic bacteria namely Streptococcus iniae and S. parauberis with a maximum zone of inhibition (0.92±0.03mm) was recorded against S. parauberis at the minimum extract concentration (3.12µg/ml). The MK-01 ethyl acetate extract shows dose dependant significant increase in antioxidant activity. The 50% cytotoxic concentration (CC50) of MK-01 ethyl acetate extract was attained at 53.71 μg/ml and the effective concentration 50 (EC50) against virus-infected Epithelioma papulosum cyprini cell lines was 8.72 μg/ml of S. carpaticus MK-01 crude ethyl acetate extract.

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Marine-derived actinomycetes have demonstrated an ability to produce novel compounds with medically relevant biological activity. Studying the diversity and biogeographical patterns of marine actinomycetes offers an opportunity to identify genera that are under environmental pressures, which may drive adaptations that yield specific biosynthetic capabilities. The present study describes research efforts to explore regions of the Atlantic Ocean, specifically around the Madeira Archipelago, where knowledge of the indigenous actinomycete diversity is scarce. A total of 400 actinomycetes were isolated, sequenced, and screened for antimicrobial and anticancer activities. The three most abundant genera identified were Streptomyces, Actinomadura, and Micromonospora. Phylogenetic analyses of the marine OTUs isolated indicated that the Madeira Archipelago is a new source of actinomycetes adapted to life in the ocean. Phylogenetic differences between offshore (>100 m from shore) and nearshore (< 100 m from shore) populations illustrates the importance of sampling offshore in order to isolate new and diverse bacterial strains. Novel phylotypes from chemically rich marine actinomycete groups like MAR4 and the genus Salinispora were isolated. Anticancer and antimicrobial assays identified Streptomyces, Micromonospora, and Salinispora as the most biologically active genera. This study illustrates the importance of bioprospecting efforts at unexplored regions of the ocean to recover bacterial strains with the potential to produce novel and interesting chemistry.

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Fifteen actinomycete strains were evaluated for their potential use in removal of polycyclic aromatic hydrocarbons (PAH). Their capability to degrade of naphthalene, phenanthrene, and pyrene was tested in minimal medium (MM) and MM with glucose as another substrate. Degradation of naphthalene in MM was observed in all isolates at different rates, reaching maximum values near to 76% in some strains of Streptomyces, Rhodococcus sp. 016 and Amycolatopsis tucumanensis DSM 45259. Maximum values of degradation of phenanthrene in MM occurred in cultures of A. tucumanensis DSM 45259 (36.2%) and Streptomyces sp. A12 (20%), while the degradation of pyrene in MM was poor and only significant with Streptomyces sp. A12 (4.3%). Because of the poor performance when growing on phenanthrene and pyrene alone, Rhodococcus sp. 20, Rhodococcus sp. 016, A. tucumanensis DSM 45259, Streptomyces sp. A2, and Streptomyces sp. A12 were challenged to an adaptation schedule of successive cultures on a fresh solid medium supplemented with PAHs, decreasing concentration of glucose in each step. As a result, an enhanced degradation of PAHs by adapted strains was observed in the presence of glucose as co-substrate, without degradation of phenanthrene and pyrene in MM while an increase to up to 50% of degradation was seen with these strains in glucose amended media. An internal fragment of the catA gene, which codes for catechol 1,2-dioxygenase, was amplified from both Rhodococcus strains, showing the potential for degradation of aromatic compounds via salycilate. These results allow us to propose the usefulness of these actinomycete strains for PAH bioremediation in the environment.

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This work aimed a survey on the biodiversity of maize endophytic actinomycete, and an evaluation of their potential to control the phytopathogenic fungi. From several regions of São Paulo state, 40 strains were isolated from the healthy maize plants. The identification of these strains, based on morphological properties and fatty acid methyl ester (FAME) profile showed that most of them belonged to the Streptomyces genus. These isolates were first screened for the growth inhibition of phytopathogenic fungi and results showed that all the isolate were able to inhibit the development of at least one tested pathogen. Two selected isolates were then evaluated for the control of P. aphanidermatum in cucumber (Cucumis sativa L.) under greenhouse conditions. Isolate 16R3B was able to reduce up to 71% damping-off incidence whereas isolate 14F1D/2 reduced the disease incidence by 36%. Damping- off control in cucumber, mainly for the isolate 16R3B, suggested for its use in greenhouse cucumber producing fields and to be tested in field trials.

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Cellulosimicrobium cellulans is one of the microorganisms that produces a wide variety of yeast cell walldegradingenzymes, β-1,3-glucanase, protease and chitinase. Dried cells of Saccharomyces cerevisiae were used as carbon and nitrogen source for cell growth and protease production. The medium components KH2PO4, KOH and dried yeast cells showed a significant effect (p<0.05) on the factorial fractional design. A second design was prepared using two factors: pH and percentage of dried yeast cells. The results showedthat the culture medium for the maximum production of protease was 0.2 g/l of MgSO4.7H2O, 2.0 g/l of(NH4)2SO4 and 8% of dried yeast cells in 0.15M phosphate buffer at pH 8.0. The maximum alkaline protease production was 7.0 ± 0.27 U/ml over the center point. Crude protease showed best activity at 50ºC and pH 7.0-8.0, and was stable at 50ºC.

Cellulosimicrobium cellulans é um microrganismo que produz uma variedade de enzimas que hidrolisam a parede celular de leveduras: β-1,3-glucanase, protease e quitinase. Célulasdesidratadas de Saccharomyces cerevisiae foram usadas como fonte de carbono e nitrogênio para o crescimento celular e produção de protease. Os componentes do meio de cultura: KH2PO4, KOH e células de levedura desidratadas mostraram efeitos significativos (p<0,05) no planejamento experimental fracionário. Um segundo planejamento foi preparado usandodois fatores: pH e porcentagem de células de levedura desidratadas. Os resultados mostraram que o meio de cultura para a produção máxima de protease foi 0,2 g/L de MgSO4.7H2O;2,0 g/L de (NH4)2SO4 e 8% de células de levedura desidratadas em tampão fosfato 0,15M e pH 8,0. A produção máxima de protease alcalina foi 7,0 ± 0,27 U/mL no ponto central. A proteasebruta apresentou atividade ótima a 50ºC e pH 7,0-8,0; e foi estável a 50ºC.

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Cellulosimicrobium cellulans is one of the microorganisms that produces a wide variety of yeast cell wall-degrading enzymes, ß-1,3-glucanase, protease and chitinase. Dried cells of Saccharomyces cerevisiae were used as carbon and nitrogen source for cell growth and protease production. The medium components KH2PO4, KOH and dried yeast cells showed a significant effect (p<0.05) on the factorial fractional design. A second design was prepared using two factors: pH and percentage of dried yeast cells. The results showed that the culture medium for the maximum production of protease was 0.2 g/l of MgSO4.7H2O, 2.0 g/l of (NH4)2SO4 and 8% of dried yeast cells in 0.15M phosphate buffer at pH 8.0. The maximum alkaline protease production was 7.0 ± 0.27 U/ml over the center point. Crude protease showed best activity at 50ºC and pH 7.0-8.0, and was stable at 50ºC.

RESUMO

Cellulosimicrobium cellulans is one of the microorganisms that produces a wide variety of yeast cell wall-degrading enzymes, -1,3-glucanase, protease and chitinase. Dried cells of Saccharomyces cerevisiae were used as carbon and nitrogen source for cell growth and protease production. The medium components KH2PO4, KOH and dried yeast cells showed a significant effect (p 0.05) on the factorial fractional design. A second design was prepared using two factors: pH and percentage of dried yeast cells. The results showed that the culture medium for the maximum production of protease was 0.2 g/l of MgSO4.7H2O, 2.0 g/l of (NH4)2SO4 and 8% of dried yeast cells in 0.15M phosphate buffer at pH 8.0. The maximum alkaline protease production was 7.0 ± 0.27 U/ml over the center point. Crude protease showed best activity at 50°C and pH 7.0-8.0, and was stable at 50°C.

Cellulosimicrobium cellulans é um microrganismo que produz uma variedade de enzimas que hidrolisam a parede celular de leveduras: -1,3-glucanase, protease e quitinase. Células desidratadas de Saccharomyces cerevisiae foram usadas como fonte de carbono e nitrogênio para o crescimento celular e produção de protease. Os componentes do meio de cultura: KH2PO4, KOH e células de levedura desidratadas mostraram efeitos significativos (p 0,05) no planejamento experimental fracionário. Um segundo planejamento foi preparado usando dois fatores: pH e porcentagem de células de levedura desidratadas. Os resultados mostraram que o meio de cultura para a produção máxima de protease foi 0,2 g/L de MgSO4.7H2O; 2,0 g/L de (NH4)2SO4 e 8% de células de levedura desidratadas em tampão fosfato 0,15M e pH 8,0. A produção máxima de protease alcalina foi 7,0 ± 0,27 U/mL no ponto central. A protease bruta apresentou atividade ótima a 50 °C e pH 7,0-8,0; e foi estável a 50°C.