Bacterial diversity and community composition in the chemocline of the meromictic alpine Lake Cadagno as revealed by 16S rDNA analysis

Bosshard, Philipp P.

doi:10.1016/s0168-6496(99)00098-7

Cited by 49 publications

(59 citation statements)

References 11 publications

(15 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These measurements were used to calculate vertical attenuation coefficients (Kd) of photosynthetically available radiation (8) for the mixolimnion and the bacterial layer. The YSI 6000 profiler and LI-COR sensors were fixed at the lowest part of a thin-layer pneumatic multisyringe sampler (3,4,31,32), which was used to take 20 simultaneous samples of 100 ml over a total depth of 2 m.…”

Section: Methodsmentioning

confidence: 99%

Long-Term Population Dynamics of Phototrophic Sulfur Bacteria in the Chemocline of Lake Cadagno, Switzerland

Tonolla

Peduzzi

Hahn

2005

Appl Environ Microbiol

View full text Add to dashboard Cite

Population analyses in water samples obtained from the chemocline of crenogenic, meromictic Lake Cadagno, Switzerland, in October for the years 1994 to 2003 were studied using in situ hybridization with specific probes. During this 10-year period, large shifts in abundance between purple and green sulfur bacteria and among different populations were obtained. Purple sulfur bacteria were the numerically most prominent phototrophic sulfur bacteria in samples obtained from 1994 to 2001, when they represented between 70 and 95% of the phototrophic sulfur bacteria. All populations of purple sulfur bacteria showed large fluctuations in time with populations belonging to the genus Lamprocystis being numerically much more important than those of the genera Chromatium and Thiocystis. Green sulfur bacteria were initially represented by Chlorobium phaeobacteroides but were replaced by Chlorobium clathratiforme by the end of the study. C. clathratiforme was the only green sulfur bacterium detected during the last 2 years of the analysis, when a shift in dominance from purple sulfur bacteria to green sulfur bacteria was observed in the chemocline. At this time, numbers of purple sulfur bacteria had decreased and those of green sulfur bacteria increased by about 1 order of magnitude and C. clathratiforme represented about 95% of the phototrophic sulfur bacteria. This major change in community structure in the chemocline was accompanied by changes in profiles of turbidity and photosynthetically available radiation, as well as for sulfide concentrations and light intensity. Overall, these findings suggest that a disruption of the chemocline in 2000 may have altered environmental niches and populations in subsequent years.Lake Cadagno is a crenogenic meromictic lake located in the catchment area of a dolomite vein rich in gypsum in the Piora valley in the southern Alps of Switzerland (46°33ЈN, 8°43ЈE). This lake is characterized by a compact chemocline with high concentrations of sulfate; steep gradients of oxygen, sulfide, and light; and a turbidity maximum that correlates to large numbers of bacteria (up to 10 7 cells ml Ϫ1 ) (5, 21, 31). Molecular methods such as 16S rRNA gene clone library analysis and subsequent in situ hybridization with specific fluorescent probes identified the most abundant bacteria in the chemocline as large-and small-celled purple sulfur bacteria. These accounted for up to 35% of all bacteria (34) and consisted of Chromatium okenii as the only representative of the largecelled purple sulfur bacteria and of four populations related to the genus Lamprocystis that represented the small-celled purple sulfur bacteria (31). Small-celled purple sulfur bacteria were most abundant with two populations accounting for 40 to 80% of the purple sulfur bacteria depending on the season (31). These populations, designated D and F, were not represented by a cultured relative, whereas the remaining populations were identified as Lamprocystis purpurea and Lamprocystis roseopersicina. L. purpurea and L. roseopersicina wer...

show abstract

Section: Methodsmentioning

confidence: 99%

Long-Term Population Dynamics of Phototrophic Sulfur Bacteria in the Chemocline of Lake Cadagno, Switzerland

Tonolla

Peduzzi

Hahn

2005

Appl Environ Microbiol

View full text Add to dashboard Cite

show abstract

“…The YSI 6000 profiler as well as two LI-193SA spherical quantum sensors (LI-COR Ltd., Lincoln, NE, USA) that were used to determine PAR-light transmission conditions (%) down to the chemocline in steps of 0.1 m were fixed at the lowest part of a thin-layer pneumatic multisyringe sampler that was used to take 20 simultaneous samples of 100 mL over a total depth of 2 m, yielding in a depth resolution of 10 cm between each sample (Tonolla et al 1999;Bosshard et al 2000a;Bosshard et al 2000b;Tonolla et al 2000).…”

Section: Samplingmentioning

confidence: 99%

Fine scale analysis of shifts in bacterial community structure in the chemocline of meromictic Lake Cadagno, Switzerland

Decristophoris¹,

Peduzzi²,

Ruggeri-Bernardi³

et al. 2009

J Limnol

View full text Add to dashboard Cite

show abstract

“…Frequencies of major bacterial phylogenetic groups in the SFD1 clone library and among freshwater bacterioplankton clones reported in the literature. Sources: Bahr et al (1996), Hiorns et al (1997), Semenova & Kuznedelov (1998), Zwart et al (1998), Crump et al (1999), Bosshard et al (2000a), Glöckner et al (2000), Urbach et al (2001) locations, indicating a cosmopolitan distribution. Especially interesting is the LD12 cluster of α-Proteobacteria, which includes SFD1-3 and SFD1-12.…”

Section: Bacterioplankton Compositionmentioning

confidence: 99%

Covariance of bacterioplankton composition and environmental variables in a temperate delta system

Stepanauskas¹,

Moran²,

Bergamaschi³

et al. 2003

Aquat. Microb. Ecol.

121

View full text Add to dashboard Cite

We examined seasonal and spatial variation in bacterioplankton composition in the Sacramento-San Joaquin River Delta (CA) using terminal restriction fragment length polymorphism (T-RFLP) analysis. Cloned 16S rRNA genes from this system were used for putative identification of taxa dominating the T-RFLP profiles. Both cloning and T-RFLP analysis indicated that Actinobacteria, Verrucomicrobia, Cytophaga-Flavobacterium and Proteobacteria were the most abundant bacterioplankton groups in the Delta. Despite the broad variety of sampled habitats (deep water channels, lakes, marshes, agricultural drains, freshwater and brackish areas), and the spatial and temporal differences in hydrology, temperature and water chemistry among the sampling campaigns, T-RFLP electropherograms from all samples were similar, indicating that the same bacterioplankton phylotypes dominated in the various habitats of the Delta throughout the year. However, principal component analysis (PCA) and partial least-squares regression (PLS) of T-RFLP profiles revealed consistent grouping of samples on a seasonal, but not a spatial, basis. β-Proteobacteria related to Ralstonia, Actinobacteria related to Microthrix, and β-Proteobacteria identical to the environmental Clone LD12 had the highest relative abundance in summer/fall T-RFLP profiles and were associated with low river flow, high pH, and a number of optical and chemical characteristics of dissolved organic carbon (DOC) indicative of an increased proportion of phytoplankton-produced organic material as opposed to allochthonous, terrestrially derived organic material. On the other hand, Geobacter-related β-Proteobacteria showed a relative increase in abundance in T-RFLP analysis during winter/spring, and probably were washed out from watershed soils or sediment. Various phylotypes associated with the same phylogenetic division, based on tentative identification of T-RFLP fragments, exhibited diverse seasonal patterns, suggesting that ecological roles of Delta bacterioplankton were partitioned at the genus or species level. KEY WORDS: Bacterioplankton biogeography · 16S rRNA · T-RFLP · Clone libraries · Dissolved organic matter Resale or republication not permitted without written consent of the publisherAquat Microb Ecol 31: [85][86][87][88][89][90][91][92][93][94][95][96][97][98] 2003 bacterioplankton. The effects of individual factors are often difficult to differentiate, however, due to the complexity of ecological interactions and due to the limitations of existing methodology.Several 16S rRNA fingerprinting techniques based on PCR have been developed for rapid comparison of natural microbial assemblages, including terminal restriction fragment length polymorphism (T-RFLP) analysis (Avaniss-Aghajani et al. 1996). Since PCR amplification of 16S rRNA genes gives highly reproducible ratios between amplicons when performed under identical conditions, and due to the analytic precision of T-RFLP analysis (Polz & Cavanaugh 1998, González et al. 2000, multivariate statistical analysis of...

show abstract

Bacterial diversity and community composition in the chemocline of the meromictic alpine Lake Cadagno as revealed by 16S rDNA analysis

Cited by 49 publications

References 11 publications

Long-Term Population Dynamics of Phototrophic Sulfur Bacteria in the Chemocline of Lake Cadagno, Switzerland

Long-Term Population Dynamics of Phototrophic Sulfur Bacteria in the Chemocline of Lake Cadagno, Switzerland

Fine scale analysis of shifts in bacterial community structure in the chemocline of meromictic Lake Cadagno, Switzerland

Covariance of bacterioplankton composition and environmental variables in a temperate delta system

Contact Info

Product

Resources

About