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1.
Curr Microbiol ; 69(5): 681-9, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24972665

RESUMEN

Artificial climbing walls represent a unique indoor environment in which humans interact closely with a variety of surface types. Climbing wall holds may mediate transmission of organisms between individuals, and yet there are no studies that identify microorganisms present on these surfaces. In the current study, the microorganisms found on climbing wall holds were characterized by analysis of amplified SSU rRNA gene sequences. In contrast to many other studies of built environments, the majority of microorganisms on holds were most closely related to microbes annotated as being recovered from environmental sources, such as soil, with human skin also representing an important source. Regional patterns were evident as rRNA gene sequences from the marine cyanobacterium Prochlorococcus were abundant in gyms found within 16 km of the ocean. Enterobacteriaceae were present on 100 % of holds surveyed, and the members detected are commonly associated with fecal matter.


Asunto(s)
Bacterias/clasificación , Bacterias/genética , Biota , Microbiología Ambiental , Análisis por Conglomerados , ADN Ribosómico/química , ADN Ribosómico/genética , Humanos , Datos de Secuencia Molecular , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Deportes
2.
Microb Ecol ; 67(3): 587-602, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24419541

RESUMEN

Mid-latitude peatlands with a temperate climate are sparsely studied and as such represent a gap in the current knowledge base regarding archaeal populations present and their roles in these environments. Phylogenetic analysis of the archaeal populations among three peatlands in the Southern Appalachians reveal not only methanogenic species but also significant populations of thaumarchaeal and crenarchaeal-related organisms of the uncultured miscellaneous crenarchaeotal group (MCG) and the terrestrial group 1.1c, as well as deep-branching Euryarchaeota primarily within the Lake Dagow sediment and rice cluster V lineages. The Thaum/Crenarchaea and deep-branching Euryarchaea represented approximately 24-83% and 2-18%, respectively, of the total SSU rRNA clones retrieved in each library, and methanogens represented approximately 14-72% of the clones retrieved. Several taxa that are either rare or novel to acidic peatlands were detected including the euryarchaeal SM1K20 cluster and thaumarchaeal/crenarchaeal-related clusters 1.1a, C3, SAGMCG-1, pSL12, and AK59. All three major groups (methanogens, Thaumarchaea/Crenarchaea, and deep-branching Euryarchaea) were detected in the RNA library, suggesting at least a minimum level of maintenance activity. Compared to their northern counterparts, Southern Appalachian peatlands appear to harbor a relatively high diversity of Archaea and exhibit a high level of intra-site heterogeneity.


Asunto(s)
Archaea/fisiología , Biodiversidad , Humedales , Archaea/clasificación , Archaea/genética , Archaea/aislamiento & purificación , Biblioteca de Genes , Datos de Secuencia Molecular , North Carolina , Filogenia , Reacción en Cadena en Tiempo Real de la Polimerasa , Análisis de Secuencia de ADN
3.
Environ Microbiol ; 13(3): 589-603, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20977571

RESUMEN

Measurements of dissolved, ascorbate-reducible and total Mn by ICP-OES revealed significantly higher concentrations during estuarine turbidity maxima (ETM) events, compared with non-events in the Columbia River. Most probable number (MPN) counts of Mn-oxidizing or Mn-reducing heterotrophs were not statistically different from that of other heterotrophs (10³ -104 cells ml⁻¹) when grown in defined media, but counts of Mn oxidizers were significantly lower in nutrient-rich medium (13 cells ml⁻¹). MPN counts of Mn oxidizers were also significantly lower on Mn(III)-pyrophosphate and glycerol (21 cells ml⁻¹). Large numbers of Rhodobacter spp. were cultured from dilutions of 10⁻² to 10⁻5, and many of these were capable of Mn(III) oxidation. Up to c. 30% of the colonies tested LBB positive, and all 77 of the successfully sequenced LBB positive colonies (of varying morphology) yielded sequences related to Rhodobacter spp. qPCR indicated that a cluster of Rhodobacter isolates and closely related strains (95-99% identity) represented approximately 1-3% of the total Bacteria, consistent with clone library results. Copy numbers of SSU rRNA genes for either Rhodobacter spp. or Bacteria were four to eightfold greater during ETM events compared with non-events. Strains of a Shewanella sp. were retrieved from the highest dilutions (10⁻5) of Mn reducers, and were also capable of Mn oxidation. The SSU rRNA gene sequences from these strains shared a high identity score (98%) with sequences obtained in clone libraries. Our results support previous findings that ETMs are zones with high microbial activity. Results indicated that Shewanella and Rhodobacter species were present in environmentally relevant concentrations, and further demonstrated that a large proportion of culturable bacteria, including Shewanella and Rhodobacter spp., were capable of Mn cycling in vitro.


Asunto(s)
Rhodobacter/aislamiento & purificación , Ríos/microbiología , Shewanella/aislamiento & purificación , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Manganeso/metabolismo , Oxidación-Reducción , Filogenia , Rhodobacter/clasificación , Rhodobacter/metabolismo , Shewanella/clasificación , Shewanella/metabolismo
4.
Geomicrobiol J ; 26(3): 189-198, 2009 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-19768133

RESUMEN

Several closely related Mn(II)-oxidizing alpha-Proteobacteria were isolated from very different marine environments: strain SI85-9A1 from the oxic/anoxic interface of a stratified Canadian fjord, strain HTCC 2156 from the surface waters off the Oregon coast, and strain AE01 from the dorsal surface of a hydrothermal vent tubeworm. 16S rRNA analysis reveals that these isolates are part of a tight phylogenetic cluster with previously characterized members of the genus Aurantimonas. Other organisms within this clade have been isolated from disparate environments such as surface waters of the Arctic and Mediterranean seas, a deep-sea hydrothermal plume, and a Caribbean coral. Further analysis of all these strains revealed that many of them are capable of oxidizing dissolved Mn(II) and producing particulate Mn(III/IV) oxides. Strains SI85-9A1 and HTCC 2156 were characterized further. Despite sharing nearly identical 16S rRNA gene sequences with the previously described Aurantimonas coralicida, whole genome DNA-DNA hybridization indicated that their overall genomic similarity is low. Polyphasic phenotype characterization further supported distinguishing characteristics among these bacteria. Thus SI85-9A1 and HTCC 2156 are described as two new species within the family 'Aurantimionadaceae': Aurantimonas manganoxydans sp. nov. and Aurantimonas litoralis sp. nov. This clade of bacteria is widely distributed around the globe and may be important contributors to Mn cycling in many environments. Our results highlight the difficulty in utilizing 16S rRNA-based approaches to investigate the microbial ecology of Mn(II) oxidation.

5.
Mo Med ; 87(9): 691-6, 1990 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2215473

RESUMEN

Comparison of the ages of patients dying at three interrelated St. Louis hospitals in 1988 has been used to study the results of similar high-quality acute hospital care when provided to dissimilar populations. The data presented by the authors leads them to conclude that in this era of mounting health costs, we have not, at least as recently as 1988, realized that an ounce of prevention if worth a pound of cure.


Asunto(s)
Hospitales con Fines de Lucro/estadística & datos numéricos , Hospitales Rurales/estadística & datos numéricos , Hospitales Urbanos/estadística & datos numéricos , Mortalidad , Adulto , Factores de Edad , Anciano , Causas de Muerte , Estudios de Evaluación como Asunto , Humanos , Illinois , Longevidad , Masculino , Indigencia Médica , Persona de Mediana Edad , Missouri/epidemiología , Estudios Retrospectivos
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