Marine Sediment Recovered Salinispora sp. Inhibits the Growth of Emerging Bacterial Pathogens and other Multi-Drug-Resistant Bacteria.

Marine obligate actinobacteria produce a wide variety of secondary metabolites with biological activity, notably those with antibiotic activity urgently needed against multi-drug-resistant bacteria. Seventy-five marine actinobacteria were isolated from a marine sediment sample collected in Punta Arena de La Ventana, Baja California Sur, Mexico. The 16S rRNA gene identification, Multi Locus Sequence Analysis, and the marine salt requirement for growth assigned seventy-one isolates as members of the genus Salinispora, grouped apart but related to the main Salinispora arenicola species clade. The ability of salinisporae to inhibit bacterial growth of Staphylococcus epidermidis, Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacer baumannii, Pseudomonas aeruginosa, and Enterobacter spp. was evaluated by cross-streaking plate and supernatant inhibition tests. Ten supernatants inhibited the growth of eight strains of S. epidermidis from patients suffering from ocular infections, two out of the eight showed growth inhibition on ten S. epidermidis strains from prosthetic joint infections. Also, it inhibited the growth of the remaining six multi-drug-resistant bacteria tested. These results showed that some Salinispora strains could produce antibacterial compounds to combat bacteria of clinical importance and prove that studying different geographical sites uncovers untapped microorganisms with metabolic potential.

Efecto in vitro del extracto crudo de un estreptomiceto causante de sarna común de papa en Sinaloa, México / In vitro effect of the crude extract of a potato common scab streptomycete in Sinaloa, Mexico

Abstract A strain isolated from potato common scab superficial lesions in El Fuerte Valley in northern Sinaloa, Mexico, was identified by 16S rRNA and morphological methods. Moreover, the effects of the crude extract of strain V2 was evaluated on radish and potato. The isolate was similar to Streptomyces acidiscabies in its morphological properties; however, the 16S rRNA gene sequence of strain V2 was neither 100% identical to this species nor to the streptomycetes previously reported in Sinaloa, Mexico. Strain V2 did not amplify any specific PCR products for genes necl and tomA, which have been found and reported in S. acidiscabies. Strain V2 produced a PCR product for the txtAB operon, which is related to the production of thaxtomin. In vitro assays using crude thaxtomin extract and a spore suspension of the organism caused necrotic symptoms on radish and potato, which were highly virulent in potato. This study reports that Streptomyces sp. V2 has a toxigenic region (TR) that is associated with the thaxtomin gene cluster.

Resumen Se aisló una cepa de una lesión superficial de sarna común de la papa en un ejemplar procedente del Valle del Fuerte, en el norte de Sinaloa, México. La cepa fue identificada por secuenciación del gen 16S ARNr, y por sus características morfológicas. Los efectos del extracto crudo de dicha cepa, llamada V2, fue evaluado en papa y rábano. El aislado fue similar a Streptomyces acidiscabies en sus características morfológicas, pero la secuencia del gen 16S ARNr de la cepa V2 no fue 100% idéntica a la de dicha especie, ni tampoco a las de cepas identificadas dentro de este taxón previamente en Sinaloa, México. La cepa V2 no amplificó los productos específicos de PCR de los genes nec1 y tomA, los cuales sí se han reportado en S. acidiscabies. La cepa V2 amplificó el producto de PCR para del operón txtAB, relacionado con la producción de taxtomina. A través de ensayos in vitro usando un extracto crudo de taxtomina y una suspensión de esporas del organismo aislado se verificó la producción de síntomas necróticos en rábano y papa, con mayor virulencia en esta última especie. Este estudio indica que Streptomyces sp. V2 tiene una región toxigénica (TR) asociada con el cluster de genes de taxtomina.

Genomic Insight into Three Marine Micromonospora sp. Strains from the Gulf of California.

Three actinomycete strains, designated BL1, BL4, and CV4, were isolated from sediment samples from the Gulf of California in 2009 together with nearly 300 other actinobacteria. Genome mining and analysis of their ∼6.4-Mb sequences confirmed the bioprospecting potential of these three bacteria belonging to the genus Micromonospora.

In vitro effect of the crude extract of a potato common scab streptomycete in Sinaloa, Mexico.

A strain isolated from potato common scab superficial lesions in El Fuerte Valley in northern Sinaloa, Mexico, was identified by 16S rRNA and morphological methods. Moreover, the effects of the crude extract of strain V2 was evaluated on radish and potato. The isolate was similar to Streptomyces acidiscabies in its morphological properties; however, the 16S rRNA gene sequence of strain V2 was neither 100% identical to this species nor to the streptomycetes previously reported in Sinaloa, Mexico. Strain V2 did not amplify any specific PCR products for genes nec1 and tomA, which have been found and reported in S. acidiscabies. Strain V2 produced a PCR product for the txtAB operon, which is related to the production of thaxtomin. In vitro assays using crude thaxtomin extract and a spore suspension of the organism caused necrotic symptoms on radish and potato, which were highly virulent in potato. This study reports that Streptomyces sp. V2 has a toxigenic region (TR) that is associated with the thaxtomin gene cluster.

Draft Genome Sequence of a Streptomycete Isolated from Potato Common Scab Lesions in the State of Sinaloa, Mexico.

Streptomyces sp. strain V2 was isolated from potato scab lesions in the state of Sinaloa, Mexico, and appears to be responsible for outbreaks in the area. The thaxtomin cluster was found in the ∼10.2-Mb genome; this cluster is associated with potato common scab disease in other potato pathogens.

Draft Genome Sequence of Two Marine Plantactinospora spp. from the Gulf of California.

Plantactinospora sp. strains BB1 and BC1 were isolated in 2009 from sediment samples of the Gulf of California from among almost 300 actinobacteria. Genome mining of their ∼8.5-Mb sequences showed the bioprospecting potential of these rare actinomycetes, providing an insight to their ecological and biotechnological importance.

Marine Actinobacteria as a source of compounds for phytopathogen control: An integrative metabolic-profiling / bioactivity and taxonomical approach.

Marine bacteria are considered as promising sources for the discovery of novel biologically active compounds. In this study, samples of sediment, invertebrate and algae were collected from the Providencia and Santa Catalina coral reef (Colombian Caribbean Sea) with the aim of isolating Actinobateria-like strain able to produce antimicrobial and quorum quenching compounds against pathogens. Several approaches were used to select actinobacterial isolates, obtaining 203 strains from all samples. According to their 16S rRNA gene sequencing, a total of 24 strains was classified within Actinobacteria represented by three genera: Streptomyces, Micromonospora, and Gordonia. In order to assess their metabolic profiles, the actinobacterial strains were grown in liquid cultures, and LC-MS-based analyses from ethyl acetate fractions were performed. Based on taxonomical classification, screening information of activity against phytopathogenic strains and quorum quenching activity, as well as metabolic profiling, six out of the 24 isolates were selected for follow-up with chemical isolation and structure identification analyses of putative metabolites involved in antimicrobial activities.

Validación y propiedades psicométricas del "cuetionario exploratorio de la personalidad III" (ceper III) en Colombia / Validation and psychometric properties of the "Exploratory Questionnaire of Personality-III" (CEPER-III) in Colombia

El objetivo de la presente investigación fue analizar la validez convergente y la fiabilidad del "Cuestionario exploratorio de la personalidad-III" (CEPER-III; Caballo, Guillen, Salazar e Irurtia, 2011) en una muestra general de 565 colombianos. El cuestionario evalúa 14 estilos de personalidad que siguen los criterios del DSM-IV (APA, 1994) y DSM-III-R (APA, 1987), aunque no se trata de trastornos. Los coeficientes alfa de Cronbach de las escalas oscilaron entre 0,75 y 0,87, indicando una adecuada consistencia interna. Las correlaciones de Pearson obtenidas entre los estilos (subescalas) del CEPER-III y los trastornos (subescalas) del "Inventario clínico multiaxial de Millon" (Millon Clinical Multiaxial Inventory-III, MCMI-III; Millon, Davis y Millon, 2007) oscilaron entre 0,40 y 0,70, apoyando la validez convergente del CEPER-III. Estos resultados indican que el CEPER-III posee adecuadas propiedades psicométricas para ser utilizado en poblacion colombiana y que sus items son comprendidos sin problemas de adecuacion cultural

The aim of this research was to analyze the convergent validity of the "Exploratory Questionnaire of Personality-III" (CEPER-III; Caballo, Guillen, Salazar, & Irurtia, 2011) in a sample of 565 participants of Colombia. The questionnaire assesses 14 personality styles that follow the diagnostic criteria of the DSM-IV (APA, 1994) and DSM-III-R (APA, 1987), although they are not disorders. The alpha Cronbach coefficients of the scales ranged from .75 to .87, indicating an adequate internal consistency. Pearson correlations obtained between the CEPERIII (subscales) styles and the Million Clinical Multiaxial Inventory-III (MCMI-III; Million, Davis and million, 2007) disorders (subscales) ranged from .40 to .70, supporting the convergent validity of the CEPER-III. These results indicate that the CEPER-III has adequate psychometric properties to be used in Colombian population and that their items are well understood without problems of cultural appropriateness

Synthesis and antiprotozoal activity of nitazoxanide-N-methylbenzimidazole hybrids.

A series of a novel hybrid compounds between nitazoxanide and N-methylbenzimidazole were synthesized starting from the corresponding N-methyl-2-nitroanilines. The new hybrid compounds (1-13) were evaluated in vitro against Giardia intestinalis, Entamoeba histolytica, Trichomonas vaginalis. NTZ, MTZ and ABZ were used as drug standards. Experimental evaluations revealed all of the new compounds (1-13) were active and showed strong activity against the three protozoa, particularly with E. histolytica where the IC50 values ranged between 3 and 69 nM. Overall, compounds 2, 5, 7, 8, 9, 11 and 12 stood out with values lower than 87 nM for all three protozoa, comparatively better than the reference drugs.

Characterisation of the first actinobacterial group isolated from a Mexican extremophile environment.

The "Cave of Crystals" (aka 'Naica') in Chihuahua Mexico is a natural unique subterranean ecosystem which mainly consists of crystals made of calcium sulfate. The main system of caves are found at a depth of 300 meters (m) below sea level with crystals that range in size from a few centimeters to 15 m. The crystals date from nearly 400,000 years old and are thought to be formed when the cave was fully covered by water. At present time, this place shows a nearly constant temperature of 55 °C over the year and a humidity of 100 % which makes this place incomparable and unbearable to animal and/or human life. In the present study, two actinobacterial groups were isolated from within this system of caves and subjected to a systematic study to establish their phylogenetic relationship to microorganisms belonging to this vast group of Gram positive bacteria. Phenotypic properties, chemotaxonomic and 16S rRNA gene sequencing show that the microorganisms are members of the family Pseudonocardiaceae and are most closely related to the genus Prauserella. The present study is the first to report the isolation and presence of Actinobacteria or any other microbial form of life in this exceptional place. Moreover, this unexpected biodiversity can also provide an insight of the antibiotic resistome present in the isolates reported in this study.

An enantioselective approach to furanoeremophilanes: (+)-9-oxoeuryopsin.

An enantioselective total synthesis of the furanoeremophilane sesquiterpene (+)-9-oxoeuryopsin 1 is reported. The synthesis involves as a key step a copper(II) triflate catalyzed tandem asymmetric conjugate addition of AlMe3 to 2-methyl-2-cyclohexen-1-one with the Feringa (S,R,R)-phosphoramidite binaphthol ligand, followed by aldol condensation of the resulting aluminum enolate with 4-methyl-3-furaldehyde 4. This tandem transformation has not been previously reported with a 2-substituted-2-cyclohexen-1-one. Conventional functional group manipulations completed the synthesis.

Two perspectives on the educational and administrative roles of the pediatric chief resident.

PURPOSE: To investigate pediatric chief residents' responsibilities and determine how chief residents and program directors view the scope of the chief resident's role. SURVEY: We distributed a 20-item survey to program directors and chief residents at all US pediatric residency programs. Questions pertained to activities performed and the level of importance of administrative, clinical, and educational activities. The survey also investigated motivating factors to become chief resident, future career plans, and level of job satisfaction. RESULTS: We received responses from 127 program directors and 101 chief residents. Of the chief residents, 98% (99/101) felt administrative tasks were very/somewhat important, followed by education, service, and research. Significantly more program directors than chief residents felt chiefs' overall workload was well balanced. Program directors gave higher ratings than chief residents on chief's ability to develop clinical skills (79% [95/121] versus 61% [61/100]) and manage stress and burnout (86% [104/121] versus 72% [72/100]). Future career plans for chief residents in decreasing order included fellowship, outpatient practice, academic practice, and working as a hospitalist. The most significant problems reported by the chief residents were lack of administrative support and lack of time spent in educational/clinical activities. CONCLUSIONS: The chief resident role is primarily administrative, but program directors and chiefs feel teaching and clinical responsibilities also are important. Although the 2 groups agreed in many areas, program directors underestimated the administrative demands placed on the chief residents, and our findings suggest the chief resident role may be more fulfilling if the balance was shifted somewhat toward teaching and clinical responsibilities.

Synthesis of demethylated nidulol via an intramolecular Michael reaction.

An expeditious synthesis of 5,7-dihydroxy-6-methylphthalide from open-chain precursors is described. The key intermediates, synthons 3 and 4, were readily obtained from accessible materials and were further transformed to a common precursor, a five-membered lactone derivative, via an intramolecular Michael addition. Lactone 2 was aromatised to the phthalide system under basic conditions. The process thus constitutes a formal synthesis of the phthalide framework.

Protected cyanohydrins in the synthesis of rotenoids: (+/-)-munduserone and (+/-)-cis-12a-hydroxymunduserone.

Short synthetic routes to the natural products (+/-)-munduserone 1 and (+/-)-cis-12a-hydroxymunduserone 9 from protected cyanohydrin 5 and nitrochromene 4 are described. The key coupling reaction of 4 and 5 gave under inverse addition conditions 9 (28%) and 2b (21%), while under normal addition conditions, a mixture of 9 (20%), dehydromunduserone 10 (9%), and enone 2b (10%) was obtained. (+/-)-Munduserone 1 is easily obtained from both 2b and 9 by 10% methanolic HCl (86%) and Zn/AcOH (71%) treatments, respectively.

Actinobacterial diversity from marine sediments collected in Mexico.

Seventeen different media known to support the growth and isolation of members of the class Actinobacteria were evaluated as selective isolation media for the recovery of this microbial group from marine sediments samples collected in the Gulf of California and the Gulf of Mexico. A general selective isolation procedure was employed for six sediments and nearly 300 actinomycetes were recovered from the selective isolation plates. Full 16S rRNA gene sequencing revealed that the isolates belonged to several actinobacterial taxa, notably to the genera Actinomadura, Dietzia, Gordonia, Micromonospora, Nonomuraea, Rhodococcus, Saccharomonospora, Saccharopolyspora, Salinispora, Streptomyces, "Solwaraspora" and Verrucosispora. Previous works on marine sediments have been restricted to the isolation of members of the genera Micromonospora, Rhodococcus and Streptomyces. This study provides further evidence that Actinobacteria present in marine habitats are not restricted to the Micromonospora-Rhodococcus-Streptomyces grouping. Indeed, this first systematic study shows the extent of actinobacterial diversity that can be found in marine sediments collected in Mexico and probably, worldwide.

Characterisation of micromonosporae from aquatic environments using molecular taxonomic methods.

Large numbers of strains assigned to the genus Micromonospora on the basis of typical colonial and pigmentation features were isolated from diverse aquatic sediments using a standard selective isolation procedure. Two hundred and six isolates and eight representatives of the genus Micromonospora were assigned to 24 multimembered groups based on a numerical analysis of banding patterns generated using BOX and ERIC primers. Representatives of multimembered groups encompassing isolated micromonosporae were the subject of 16S rRNA gene sequencing analyses. Good congruence was found between the molecular fingerprinting and 16S rRNA sequence data indicating that the groups based upon the former are taxonomically meaningful. Nearly all of the isolates that were chosen for the 16S rRNA gene sequencing analyses showed that the ecosystems studied are a rich source of novel micromonosporae. These findings have implications for high throughput screening for novel micromonosporae as BOX and ERIC fingerprinting, which is rapid and reproducible, can be applied as a robust dereplication procedure to indicate which environmental isolates have been cultured previously.

Streptomyces sudanensis sp. nov., a new pathogen isolated from patients with actinomycetoma.

Nine strains isolated from mycetoma patients and received as Streptomyces somaliensis were the subject of a polyphasic taxonomic study. The organisms shared chemical markers consistent with their classification in the genus Streptomyces and formed two distinct monophyletic subclades in the Streptomyces 16S rRNA gene tree. The first subclade contained four organisms, including the type strain of S. somaliensis, and the second clade the remaining five strains which had almost identical 16S rRNA sequences. Members of the two subclades were sharply separated using DNA:DNA relatedness and phenotypic data which also showed that the subclade 1 strains formed an heterogeneous group. In contrast, the subclade 2 strains were assigned to a single genomic species and had identical phenotypic profiles. It is evident from these data that the subclade 2 strains should be recognised as a new species of Streptomyces. The name proposed for this new species is Streptomyces sudanensis sp. nov. The type strain is SD 504(T) (DSM = 41923(T) = NRRL B-24575(T)).

Salinispora arenicola gen. nov., sp. nov. and Salinispora tropica sp. nov., obligate marine actinomycetes belonging to the family Micromonosporaceae.

A taxonomic study was carried out to clarify the taxonomy of representatives of a group of marine actinomycetes previously designated MAR 1 and considered to belong to the family Micromonosporaceae. The organisms had phenotypic properties consistent with their assignment to this taxon. The strains formed a distinct taxon in the 16S rRNA Micromonosporaceae gene tree and shared a range of phenotypic properties that distinguished them from members of all of the genera with validly published names classified in this family. The name proposed for this novel taxon is Salinispora gen. nov. The genus contains two species recognized using a range of genotypic and phenotypic criteria, including comparative 16S-23S rRNA gene spacer region and DNA-DNA relatedness data. The names proposed for these taxa are Salinispora arenicola sp. nov., the type species, and Salinispora tropica sp. nov.; the type strains of these novel species have been deposited in service culture collections as strain CNH-643(T) (=ATCC BAA-917(T)=DSM 44819(T)) and strain CNB-440(T) (=ATCC BAA-916(T)=DSM 44818(T)), respectively.

Reclassification of Nonomuraea flexuosa (Meyer 1989) Zhang et al. 1998 as Thermopolyspora flexuosa gen. nov., comb. nov., nom. rev.

A polyphasic study was undertaken to clarify the taxonomic position of Nonomuraea flexuosa DSM 41386(T). The distinct 16S rRNA gene sequence phyletic branch formed by this strain was equated with nine related monophyletic clades composed of representatives of the genera classified in the family Streptosporangiaceae. The organism produced a PCR product characteristic of this taxon when examined using a set of oligonucleotide primers specific for members of the family Streptosporangiaceae. Strain DSM 41386(T) could also be distinguished from representatives of the nine genera assigned to this family using a combination of chemotaxonomic, morphological and physiological properties. It is evident from the genotypic and phenotypic data that strain DSM 41386(T) is misclassified in the genus Nonomuraea and merits recognition as a monospecific genus within the family Streptosporangiaceae. It is proposed that the name Thermopolyspora flexuosa gen. nov., comb. nov., nom. rev. be used for this purpose, with the type strain DSM 41386(T) (=NRRL B-24348(T)).

Diversity of cultivable actinobacteria in geographically widespread marine sediments.

Reports describing actinobacteria isolated from marine environments have been dominated by Micromonospora, Rhodococcus and Streptomyces species. Recent culture-independent studies have shown that marine environments contain a high diversity of actinobacterial species that are rarely, if at all, recovered by cultivation-based methods. In this study, it is shown that cultivation-independent methods can be used to guide the application of selective isolation methods. The detection of marine-derived actinobacterial species that have previously only been reported from terrestrial habitats is highlighted. This study provides good evidence that the previously described low diversity of actinobacterial species isolated from marine environments does not reflect an actual low species diversity, and that the use of informed selective isolation procedures can aid in the isolation of members of novel taxa.