Ultramicrobacteria
Mostrando 1-11 de 11 artigos, teses e dissertações.
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1. Aspectos metabólicos, fisiológicos e taxonômicos de actinomiceto produtor de exopolissacarídeos, proveniente de águas subterrâneas contaminadas (São Carlos, SP).
Strains Lc (CCT 7277) and Lg (CCT 7137), isolated from landfill leachate-contaminated groundwater and found to produce exopolysaccharides (ESP), were characterized by polyphasic taxonomy. The growth and EPS production of Lg strain on sugarcane molasses, at concentrations between 2% and 10% and on the standard GYM medium were studied and its responses to nutr
Publicado em: 2005
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2. Strain-Specific Differences in the Grazing Sensitivities of Closely Related Ultramicrobacteria Affiliated with the Polynucleobacter Cluster
Ultramicrobacteria (cell volume < 0.1 μm3) are the numerically dominant organisms in the plankton of marine and freshwater habitats. Flagellates and other protists are assumed to be the most important predators of these ultramicrobacteria as well as of larger planktonic bacteria. However, due to controversial observations conducted previously, it is not cle
American Society for Microbiology.
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3. Isolation and Characterization of Ultramicrobacteria from a Gulf Coast Estuary
Viable bacteria were recovered from estuarine waters passed through a 0.2-μm polycarbonate membrane filter. The recovery method included the use of a dilute nutrient broth for primary enrichment followed by conditioning of the organism to a dilute nutrient solid medium. These bacteria were gram-negative rods and coccobacilli having an NaCl requirement and,
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4. Isolation of Novel Ultramicrobacteria Classified as Actinobacteria from Five Freshwater Habitats in Europe and Asia
We describe the first freshwater members of the class Actinobacteria that have been isolated. Nine ultramicro-size (<0.1 μm3) strains were isolated from five freshwater habitats in Europe and Asia. These habitats represent a broad spectrum of ecosystems, ranging from deep oligotrophic lakes to shallow hypertrophic lakes. Even when the isolated strains were
American Society for Microbiology.
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5. Physiological Responses to Starvation in the Marine Oligotrophic Ultramicrobacterium Sphingomonas sp. Strain RB2256
Sphingomonas sp. strain RB2256 is representative of the ultramicrobacteria that proliferate in oligotrophic marine waters. While this class of bacteria is well adapted for growth with low concentrations of nutrients, their ability to respond to complete nutrient deprivation has not previously been investigated. In this study, we examined two-dimensional prot
American Society for Microbiology.
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6. Novel anaerobic ultramicrobacteria belonging to the Verrucomicrobiales lineage of bacterial descent isolated by dilution culture from anoxic rice paddy soil.
The use of dilution culture techniques to cultivate saccharolytic bacteria present in the anoxic soil of flooded rice microcosms allowed the isolation of three new strains of bacteria, typified by their small cell sizes, with culturable numbers estimated at between 1.2 x 10(5) and 7.3 x 10(5) cells per g of dry soil. The average cell volumes of all three str
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7. Microcultural Study of Bacterial Size Changes and Microcolony and Ultramicrocolony Formation by Heterotrophic Bacteria in Seawater †
With a microculture technique and time-lapse, phase-contrast photomicrography, it was possible to follow the division of individual cells and the development of microcolonies of bacteria in freshly collected marine water samples. A certain number of marine bacteria, upon inoculation onto a nutrient rich agar surface, displayed an increase in size as well as
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8. Implications of rRNA Operon Copy Number and Ribosome Content in the Marine Oligotrophic Ultramicrobacterium Sphingomonas sp. Strain RB2256
Sphingomonas sp. strain RB2256 is a representative of the dominant class of ultramicrobacteria that are present in marine oligotrophic waters. In this study we examined the rRNA copy number and ribosome content of RB2256 to identify factors that may be associated with the relatively low rate of growth exhibited by the organism. It was found that RB2256 conta
American Society for Microbiology.
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9. Isolation of Strains Belonging to the Cosmopolitan Polynucleobacter necessarius Cluster from Freshwater Habitats Located in Three Climatic Zones
More than 40 bacterial strains belonging to the cosmopolitan Polynucleobacter necessarius cluster (Betaproteobacteria) were isolated from a broad spectrum of freshwater habitats located in three climatic zones. Sequences affiliated with the freshwater P. necessarius cluster are among the most frequently detected in studies on bacterial diversity in freshwate
American Society for Microbiology.
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10. Phospholipid ester-linked fatty acid profile changes during nutrient deprivation of Vibrio cholerae: increases in the trans/cis ratio and proportions of cyclopropyl fatty acids.
The phospholipid ester-linked fatty acids of 0-day-, 7-day-, and 30-day-starved cultures of Vibrio cholerae were compared. Statistically significant trends were noted in the fatty acid profiles as the cells starved. The amount of the cis-monoenoic fatty acids declined (e.g., 16:1 omega 7c: 0 day, 39%; 7 day, 18%; 30 day, 11%). In contrast, the saturated fatt
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11. Isolation of Typical Marine Bacteria by Dilution Culture: Growth, Maintenance, and Characteristics of Isolates under Laboratory Conditions
Marine bacteria in Resurrection Bay near Seward, Alaska, and in the central North Sea off the Dutch coast were cultured in filtered autoclaved seawater following dilution to extinction. The populations present before dilution varied from 0.11 × 109 to 1.07 × 109 cells per liter. The mean cell volume varied between 0.042 and 0.074 μm3, and the mean apparen