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1.
To characterize the archaeal community composition in soil originating iron-manganese nodules, four types of soils—brown soil, yellow-cinnamon soil, yellow brown soil and red soil—and their associated iron-manganese nodules were collected from Queyu (QY), Zaoyang (ZY), Wuhan (WH) and Guiyang (GY), China, respectively, and subjected to quantitative polymerase chain reaction, cloning and sequencing analyses. The results showed that the archaeal 16S rRNA gene copy numbers in nodules, ranging between 3.59 × 10 2 and 4.17 × 10 3 copies g ?1 dry nodule, were about 50–1000 times lower than those in their corresponding soils (1.87 × 10 5 to 1.08 × 10 6 copies g ?1 dry soil), correlating with the low organic matter in the nodules, while archaea accounted for a relatively higher proportion of total prokaryote in nodules than in soils. Community composition analysis suggested that the archaeal diversity in both soils and nodules were much lower than bacterial, but archaeal community structures were similar to each other among the soils and nodules from the same location but varied among four locations, converse to the previous observation that bacterial community shifted markedly between nodules and soils as the result of habitat filtering. The archaeal communities in both soils and nodules were predominated by Thaumarchaeota Group I.1b with the relative abundance ranging between 73.88 and 94.17%, except that Euryarchaeota dominated the archaeal community in one nodule sample (WHn) developed from lake sediment. The finding shed new light on the archaeal diversity and their ecophysiology in different habitats, and further supported the opinion that archaea are more adaptable to stress and unfavorable conditions. 相似文献
2.
This study evaluated the effect of inorganic mercury (Hg) on bacterial community and diversity in different soils. Three soils—neutral, alkaline and acidic—were spiked with six different concentrations of Hg ranging from 0 to 200 mg kg−1 and aged for 90 days. At the end of the ageing period, 18 samples from three different soils were investigated for bacterial community structure and soil physicochemical properties. Illumina MiSeq-based 16s ribosomal RNA (rRNA) amplicon sequencing revealed the alteration in the bacterial community between un-spiked control soils and Hg-spiked soils. Among the bacterial groups, Actinobacteria (22.65%) were the most abundant phyla in all samples followed by Proteobacteria (21.95%), Bacteroidetes (4.15%), Firmicutes (2.9%) and Acidobacteria (2.04%). However, the largest group showing increased abundance with higher Hg doses was the unclassified group (45.86%), followed by Proteobacteria. Mercury had a considerable negative impact on key soil functional bacteria such as ammonium oxidizers and nitrifiers. Canonical correspondence analysis (CCA) indicated that among the measured soil properties, Hg had a major influence on bacterial community structure. Furthermore, nonlinear regression analysis confirmed that Hg significantly decreased soil bacterial alpha diversity in lower organic carbon containing neutral and alkaline soils, whereas in acidic soil with higher organic carbon there was no significant correlation. EC20 values obtained by a nonlinear regression analysis indicated that Hg significantly decreased soil bacterial diversity in concentrations lower than several guideline values. 相似文献
3.
In order to estimate how pollution affects the bacterial community structure and composition of sediments, chemical and molecular
approaches were combined to investigate eight stations around the Bizerte lagoon. Terminal restriction fragment length polymorphism
(T-RFLP) analysis of PCR-amplified 16S rRNA genes revealed that each station was characterized by a specific bacterial community
structure. The combination of this data with those of chemical analysis showed a correlation between the bacterial fingerprint
and the pollutant content, principally with hydrocarbon pollution. The composition of the bacterial community of two contrasted
stations related to the pollution revealed sequences affiliated to α, β, γ, δ, ε subclass of the Proteobacteria, Actinobacteria, and Acidobacteria in both stations although in different extent. Gamma and delta subclass of the Proteobacteria were dominant and represent 70% of clones in the heavy-metal-contaminated station and 47% in the polyaromatic hydrocarbon
(PAH)-contaminated. Nevertheless, most of the sequences found were unaffiliated to cultured bacteria. The adaptation of the
bacterial community mainly to PAH compounds demonstrated here and the fact that these bacterial communities are mainly unknown
suggest that the Bizerte lagoon is an interesting environment to understand the capacity of bacteria to cope with some pollutants. 相似文献
4.
Diverse intercropping system has been used to control disease and improve productivity in the field. In this research, the bacterial communities in salt–alkali soils of monoculture and intercropping mulberry and soybean were studied using 454‐pyrosequencing of the 16S rDNA gene. The dominant taxonomic groups were Proteobacteria, Acidobacteria, Actinobacteria, Chloroflexi, Bacteroidetes, Planctomycetes and Gemmatimonadetes and these were present across all samples. However, the diversity and composition of bacterial communities varied between monoculture and intercropping samples. The estimated bacterial diversity (H') was higher with intercropping soybean than in monoculture soybean, whereas H' showed an opposite pattern in monoculture and intercropping mulberry. Populations of Actinobacteria, Acidobacteria, and Proteobacteria were variable, depending on growth of plants as monoculture or intercropped. Most of Actinobacteria and Chloroflexi were found in intercropping samples, while Acidobacteria and Proteobacteria were present at a higher percentage in monoculture samples. The plant diversity of aboveground and microbial diversity of belowground was linked and soil pH seemed to influence the bacterial community. Finally, the specific plant species was the major factor that determined the bacterial community in the salt–alkali soils. 相似文献
5.
Temporary rivers are characterized by recurrent dry phases, and global warming will stress their hydrology by amplifying extreme
events. Microbial degradation and transformation of organic matter (OM) in riverbed sediment are key processes with regard
to carbon and nutrient fluxes. In this study, we describe structural and functional changes of benthic microbial communities
in a riverine environment subject to hydrological fluctuation. Sampling was carried out in the outlet section of the Mulargia
River (Sardinia, Italy) under various water regimes, including one flood event. Overall, sediments were characterized by low
bacterial cell abundance (range 0.6–1.8 × 10 9 cell g −1) as a consequence of their low nutrient and OM concentrations. No major differences were found in the community composition.
Alpha- Proteobacteria dominated during the whole year (range 21–30%) followed by Beta- Proteobacteria, Gamma- Proteobacteria, and Cytophaga- Flavobacteria which always contributed <18%. Planctomycetes and Firmicutes were found in smaller amounts (<7%). In spring, when the highest total organic carbon content was also detected (0.42% w/w),
both bacterial abundance and C production (BCP, 170 nmol C h −1 g −1) reached relatively high values. During the flood event, an increase in BCP and the highest values of community respiration
(CR, 74 nmol C h −1 g −1) were observed. Moreover, most of the extracellular enzyme activities (EEA) changed significantly during the flood. The variation
of the water flow itself can explain part of these changes and other factors also come into play. The presence of different
patterns of functional parameters could suggest that the quality of the OM could be the major driving force in nutrient flux. 相似文献
6.
DNA-based pyrosequencing analysis of the V1- V3 16S rRNA gene region was used to identify bacteria community and shift during early stages of wood colonization in boreal forest soils. The dataset comprised 142,447 sequences and was affiliated to 11 bacteria phyla, 25 classes and 233 genera. The dominant groups across all samples were Proteobacteria, followed by Bacteroidetes, Acidobacteria, Actinobacteria, Amatimonadetes, Planctomycetes and TM7 group. The community structure of the primary wood-inhabiting bacteria differed between types of forest soils and the composition of bacteria remained stable over prolonged incubation time. The results suggest that variations in soil bacterial community composition have an influence on the wood-inhabiting bacterial structure. 相似文献
7.
A bstract
The phylogenetic composition, three-dimensional structure and dynamics of bacterial communities in river biofilms generated
in a rotating annular reactor system were studied by fluorescent in situ hybridization (FISH) and confocal laser scanning microscopy (CLSM). Biofilms grew on independently removable polycarbonate
slides exposed in the reactor system with natural river water as inoculum and sole nutrient and carbon source. The microbial
biofilm community developed from attached single cells and distinct microcolonies via a more confluent structure characterized
by various filamentous bacteria to a mature biofilm rich in polymeric material with fewer cells on a per-area basis after
56 days. During the different stages of biofilm development, characteristic microcolonies and cell morphotypes could be identified
as typical features of the investigated lotic biofilms. In situ analysis using a comprehensive suite of rRNA-targeted probes visualized individual cells within the alpha-, beta-, and gamma- Proteobacteria as well as the Cytophaga–Flavobacterium group as major parts of the attached community. The relative abundance of these major groups was determined by using digital
image analysis to measure specific cell numbers as well as specific cell area after in situ probing. Within the lotic biofilm community, 87% of the whole bacterial cell area and 79% of the total cell counts hybridized
with a Bacteria specific probe. During initial biofilm development, beta- Proteobacteria dominated the bacterial population. This was followed by a rapid increase of alpha- Proteobacteria and bacteria affiliated to the Cytophaga–Flavobacterium group. In mature biofilms, alpha- Proteobacteria and Cytophaga–Flavobacteria continued to be the prevalent bacterial groups. Beta- Proteobacteria constituted the morphologically most diverse group within the biofilm communities, and more narrow phylogenetic staining
revealed the importance of distinct phylotypes within the beta1- Proteobacteria for the composition of the microbial community. The presence of sulfate-reducing bacteria affiliated to the Desulfovibrionaceae and Desulfobacteriaceae confirmed the range of metabolic potential within the lotic biofilms.
Received: 24 September 1998; Accepted: 17 February 1999 相似文献
8.
Soil microorganisms play vital roles in recovering and maintaining the health of ecosystems, particularly in fragile Karst
ecosystems that are easily degraded after cultivation. We investigated the composition and diversity of soil bacterial communities,
based on RFLP and 16S rDNA sequencing, in a cropland, a naturally revegetated land with former cultivation disturbance and
a primeval forest in the subtropical Karst of southwest China. Our results illustrated that Proteobacteria accounted for 44.8% of the 600 tested clones, making it the most dominant phylum observed. This phylum was followed by Acidobacteria and Planctomycetes for the three Karst soils analyzed. Compared with the primeval forest soil, the proportions of Proteobacteria were decreased by 30.2 and 37.9%, while Acidobacteria increased by 93.9 and 87.9%, and the Shannon-Wiener diversity indices and the physicochemical parameters declined in the
cropland and the revegetated land, respectively. Among the three soils, the proportion of dominant bacterial phyla and the
diversity indices in the revegetated land were similar to the cropland, implying the bacterial community in the cropland was
relatively stable, and the after-effects of cultivation were difficult to eliminate. However, similar distributions of the
four Proteobacteria subphyla were observed between the revegetated land and the primeval forest soil. Furthermore, the proportion of Rhizobiales belonging to α- Proteobacteria was sharply decreased with cultivation compared to the primeval forest soil, while a small cluster of Rhizobiales recurred with vegetation recovery. These results indicated that although the subphyla of the dominant bacterial phylum had
some positive responses to 20 years of vegetation recovery, it is a slow process. Our results suggest that priority should
be given to conserve the primeval forest and inoculation of functional microorganisms on the basis of vegetation recovery
may be more effective for the restoration of Karst ecosystems after cultivation. 相似文献
9.
Although soil structure largely determines energy flows and the distribution and composition of soil microhabitats, little is known about how microbial community composition is influenced by soil structural characteristics and organic matter compartmentalization dynamics. A UV irradiation-based procedure was developed to specifically isolate inner-microaggregate microbial communities, thus providing the means to analyze these communities in relation to their environment. Whole- and inner-microaggregate fractions of undisturbed soil and soils reclaimed after disturbance by surface coal mining were analyzed using 16S rDNA terminal restriction fragment polymorphism (T-RFLP) and sequence analyses to determine salient bacterial community structural characteristics. We hypothesized that inner-microaggregate environments select for definable microbial communities and that, due to their sequestered environment, inner-microaggregate communities would not be significantly impacted by disturbance. However, T-RFLP analysis indicated distinct differences between bacterial populations of inner-microaggregates of undisturbed and reclaimed soils. While both undisturbed and reclaimed inner-microaggregate bacterial communities were found dominated by Actinobacteria, undisturbed soils contained only Actinobacteridae, while in inner-microaggregates of reclaimed soils Rubrobacteridae predominate. Spatial stratification of division-level lineages within microaggregates was also evidenced, with Proteobacteria clones being prevalent in libraries derived from whole microaggregates. The fractionation methods employed in this study therefore represent a valuable tool for defining relationships between biodiversity and soil structure. 相似文献
10.
Soil bacterial communities play an important role in nutrient recycling and storage in terrestrial ecosystems. Loess soils are one of the most important soil resources for maintaining the stability of vegetation ecosystems and are mainly distributed in northwest China. Estimating the distributions and affecting factors of soil bacterial communities associated with various types of vegetation will inform our understanding of the effect of vegetation restoration and climate change on these processes. In this study, we collected soil samples from 15 sites from north to south on the Loess Plateau of China that represent different ecosystem types and analyzed the distributions of soil bacterial communities by high-throughput 454 pyrosequencing. The results showed that the 142444 sequences were grouped into 36816 operational taxonomic units (OTUs) based on 97% similarity. The results of the analysis showed that the dominant taxonomic phyla observed in all samples were Actinobacteria, Proteobacteria, Chloroflexi, Acidobacteria and Planctomycetes. Actinobacteria and Proteobacteria were the two most abundant groups in all samples. The relative abundance of Actinobacteria increased from 14.73% to 40.22% as the ecosystem changed from forest to sandy, while the relative abundance of Proteobacteria decreased from 35.35% to 21.40%. Actinobacteria and Proteobacteria had significant correlations with mean annual precipitation (MAP), pH, and soil moisture and nutrients. MAP was significantly correlated with soil chemical and physical properties. The relative abundance of Actinobacteria, Proteobacteria and Planctomycetes correlated significantly with MAP, suggesting that MAP was a key factor that affected the soil bacterial community composition. However, along with the MAP gradient, Chloroflexi, Bacteroidetes and Cyanobacteria had narrow ranges that did not significantly vary with the soil and environmental factors. Overall, we conclude that the edaphic properties and/or vegetation types are driving bacterial community composition. MAP was a key factor that affects the composition of the soil bacteria on the Loess Plateau of China. 相似文献
11.
Forest management often results in changes in the soil and its microbial communities. In the present study, differences in
the soil bacterial community caused by forest management practices were characterized using small subunit (SSU) ribosomal
RNA (rRNA) gene clone libraries. The communities were from a native hardwood forest (HWD) and two adjacent conifer plantations
in a low-elevation montane, subtropical experimental forest at the Lienhuachi Experimental Forest (LHCEF) in central Taiwan.
At this locality, the elevation ranges from 600 to 950 m, the mean annual precipitation is 2,200 mm, the mean annual temperature
is 20.8°C, and the soil pH is 4. The conifer forests included a Cunninghamia konishii Hay (CNH) plantation of 40 years and an old growth Calocedrus formosana (Florin) Florin (CLC) forest of 80 years. A total of 476 clones were sequenced and assigned into 12 phylogenetic groups.
Proteobacteria-affiliated clones (53%) predominated in the library from HWD soils. In contrast, Acidobacteria was the most abundant phylum and comprised 39% and 57% in the CLC and CNH libraries, respectively. Similarly, the most abundant
OTUs in HWD soils were greatly reduced or absent in the CLC and CNH soils. Based on several diversity indices, the numbers
of abundant OTUs and singletons, and rarefaction curves, the diversity of the HWD community (0.95 in evenness and Shannon
diversity indices) was somewhat less than that in the CNH soils (0.97 in evenness and Shannon diversity indices). The diversity
of the community in CLC soils was intermediate. The differences in diversity among the three communities may also reflect
changes in abundances of a few OTUs. The CNH forest soil community may be still in a successional phase that is only partially
stabilized after 40 years. Analysis of molecular variance also revealed that the bacterial community composition of HWD soils
was significantly different from CLC and CNH soils ( p = 0.001). These results suggest that the disturbance of forest conversion and tree species composition are important factors
influencing the soil bacterial community among three forest ecosystems in the same climate. 相似文献
12.
Glacier forefield chronosequences, initially composed of barren substrate after glacier retreat, are ideal locations to study
primary microbial colonization and succession in a natural environment. We characterized the structure and composition of
bacterial, archaeal and fungal communities in exposed rock substrates along the Damma glacier forefield in central Switzerland.
Soil samples were taken along the forefield from sites ranging from fine granite sand devoid of vegetation near the glacier
terminus to well-developed soils covered with vegetation. The microbial communities were studied with genetic profiling (T-RFLP)
and sequencing of clone libraries. According to the T-RFLP profiles, bacteria showed a high Shannon diversity index ( H) (ranging from 2.3 to 3.4) with no trend along the forefield. The major bacterial lineages were Proteobacteria, Actinobacteria, Acidobacteria, Firmicutes and Cyanobacteria. An interesting finding was that Euryarchaeota were predominantly colonizing young soils and Crenarchaeota mainly mature soils. Fungi shifted from an Ascomycota-dominated community in young soils to a more Basidiomycota-dominated community in old soils. Redundancy analysis indicated that base saturation, pH, soil C and N contents and plant
coverage, all related to soil age, correlated with the microbial succession along the forefield. 相似文献
13.
The alteration of the organic matter (OM) and the composition of bacterial community in microbial fuel cells (MFCs) supplied with soil (S) and a composted organic fertilizer (A) was examined at the beginning and at the end of 3 weeks of incubation under current-producing as well as no-current-producing conditions. Denaturing gradient gel electrophoresis revealed a significant alteration of the microbial community structure in MFCs generating electricity as compared with no-current-producing MFCs. The genetic diversity of cultivable bacterial communities was assessed by random amplified polymorphic DNA (RAPD) analysis of 106 bacterial isolates obtained by using both generic and elective media. Sequencing of the 16S rRNA genes of the more representative RAPD groups indicated that over 50.4% of the isolates from MFCs fed with S were Proteobacteria, 25.1% Firmicutes, and 24.5% Actinobacteria, whereas in MFCs supplied with A 100% of the dominant species belonged to γ- Proteobacteria. The chemical analysis performed by fractioning the OM and using thermal analysis showed that the amount of total organic carbon contained in the soluble phase of the electrochemically active chambers significantly decreased as compared to the no-current-producing systems, whereas the OM of the solid phase became more humified and aromatic along with electricity generation, suggesting a significant stimulation of a humification process of the OM. These findings demonstrated that electroactive bacteria are commonly present in aerobic organic substrates such as soil or a fertilizer and that MFCs could represent a powerful tool for exploring the mineralization and humification processes of the soil OM. 相似文献
14.
The objective of this study was to characterize the bacterial community composition in the bulk soil, rhizosphere soil and root tissue of the tomato plant ( Lycopersicum esculentum Mill). 16S ribosomal DNA (rDNA) from the bacterial community was amplified using PCR, and sequence analysis of 16S rDNA clones was subsequently used for bacterial identification and phylogenetic classification. Phylogenetic analysis of clones (total of 68) from the bulk soil, rhizosphere and root tissues showed that about 50% of the bacteria belonged to the α-, β-, γ-, and δ- Proteobacteria or Cytophaga–Flavobacterium–Bacteroides (CFB) phyla, with only one high G+C clone identified. A number of diverse bacteria were identified within Proteobacteria, while 87% of the bacteria belonged to the genus Flavobacterium within the CFB phylum, which is a unique finding for tomato plants. Our results will be of interest to those wanting to identify bacteria that can promote plant growth or resistance to diseases. 相似文献
15.
为了解大豆根际细菌群落结构多样性及根际细菌群落结构的变化,该研究以大豆苗期和成熟期的根际土壤为材料,采用Illumina高通量测序技术测定细菌16S rRNA V3+V4区序列,探究大豆不同生育期根际土壤细菌群落结构的变化。对原始数据进行拼接、过滤、去除嵌合体序列和聚类分析等数据处理,并对OTU进行分类学注释。在此基础上运用ANOVA分析物种组成变化,Alpha多样性指数研究细菌多样性变化。结果表明:细菌丰富度和多样性在不同生育期有显著变化,其中成熟期土壤中的细菌丰富度和多样性指数均明显高于苗期; 变形菌、放线菌、酸杆菌是大豆根际的优势菌门,其含量在不同生育期也有显著变化; 假诺卡氏菌属、糖丝菌属、鞘氨醇单胞菌属是大豆根际的优势菌属,这些菌属中的部分菌群属于根际促生菌,具有潜在的促生效应。这些结果证实大豆的生育期对根际土壤细菌群落结构有重要影响。 相似文献
16.
Communities of archaea, bacteria, and fungi were examined in forest soils located in the Oregon Coast Range and the inland
Cascade Mountains. Soils from replicated plots of Douglas-fir ( Pseudotsuga menziesii) and red alder ( Alnus rubra) were characterized using fungal ITS (internal transcribed spacer region), eubacterial 16S rRNA, and archaeal 16S rRNA primers.
Population size was measured with quantitative (Q)-PCR and composition was examined using length heterogeneity (LH)-PCR for
fungal composition, terminal restriction fragment length (T-RFLP) profiles for bacterial and archaeal composition, and sequencing
to identify dominant community members. Whereas fungal and archaeal composition varied between sites and dominant tree species,
bacterial communities only varied between sites. The abundance of archaeal gene copy numbers was found to be greater in coastal
compared to montane soils accounting for 11% of the prokaryotic community. Crenarchaea groups 1.1a-associated, 1.1b, 1.1c, and 1.1c-associated were putatively identified. A greater abundance of Crenarchaea 1.1b indicator fragments was found in acidic (pH 4) soils with low C:N ratios under red alder. In coastal soils, 25% of fungal
sequences were putatively identified as basidiomycetous yeasts belonging to the genus Cryptococcus. Although the function of these yeasts in soil is not known, they could significantly contribute to decomposition processes
in coastal soils distinguished by rapid tree growth, high N content, low pH, and frequent water-saturation events. 相似文献
17.
The Pacific nodule province covers about 4.5 million km 2 in the eastern tropical Pacific with abundance of polymetallic nodules. Microbes are believed to play large roles in the
metal cycling in many environments, but the microbial community in the Pacific nodule province has never been studied. Phylogenetic
studies based on 16S rRNA gene sequence analysis, together with bacterial cultivation were used to study the microbial populations
in the Pacific nodule province (A core) deep-sea sediment. Bacterial 16S rRNA gene sequence analysisdemonstrated that Proteobacteria division mainly of γ- Proteobacteria dominated the microbial community of the nodule province A core. Among the γ- Proteobacteria, Shewanella species which were known as Fe(□), Mn(□) reducing bacteria were found prevalent. Besides Proteobacteria, Green nonsulfur bacteria, the candidate subdivision OP3, Cytophaga-Flexibacter-Bacteroides bacteria and novel unidentified
strains were also detected. Archaeal 16S rDNA sequence analysis data and results from hybridization with crenarchaeotal marine
group I specific probe revealed that all archaea detected at the station belong to Crenarchaeota nonthermophilic marinegroup
I. Bacteria assigned to the gamma Proteobacteria wereisolated, none of them showed capability of manganese oxidation.
These authors contributed equally to this paper. 相似文献
18.
Waste stabilization ponds are a simple, low-cost extensive process for treating wastewater, and well adapted to low socio-economic
conditions in developing countries where the microbial populations in these systems are not well characterized. The phylogenetic
bacterial community structure within a Tunisian wastewater stabilization plant treating domestic wastewater was assessed by
Terminal Restriction Fragment Length Polymorphism method targeting 16S rRNA genes and by the APLAUS+ software of the Microbial
Community Analysis (MiCA) web based tool. The dimeric enzymatic digestion with HaeIII and HinfI restriction enzymes revealed high bacterial diversity within the plant where 11 bacterial phyla were identified. The total
bacterial community structure includes bacteria catalysing nitrogen and phosphorus removal and bacteria involved in the sulfur
cycle. The bacterial community was characterized by the dominance of Proteobacteria which was the most populous phylum (60%) followed by the Actinobacteria (20%), the Firmicutes (10.3%), the Bacteroidetes (2.3%), the Nitrospira (2.2%). Minor bacterial phyla groups occupied smaller fractions such as Chloroflexi, Deferribacteres and Verrumicrobia. T-RFLP analysis revealed also that The Proteobacteria phylum was characterized by the dominance of bacteria of The Gammaproteobacteria class. 相似文献
19.
Biogeochemical and microbiological characterization of marine sediments taken from the Yellow Sea of South Korea was carried
out. One hundred and thirty six bacterial strains were isolated, characterized and phylogenetic relationship was evaluated.
The gene sequences of 16S rDNA regions were examined to study the phylogenetic analysis of bacterial community in the marine
sediments. Among 136 isolates, 5 bacterial isolates were identified as novel members, remaining 131 isolates were fall into
5 major linkages of bacterial phyla represented as follows: Firmicutes,, -@P roteobacteria, High G + C and Bacteroidetes. Bacterial community in sediments mainly dominated by Firmicute (58.77%) and followed by @- Proteobacteria (38.16%). @- Proteobacteria domain highly diverged and mainly consists of the genera Vibrio, Marinobacterium, Photobacterium, Pseudoalteromonas, Oceanisphaera, Halomonas, Alteromonas, Stenotrophomas and Pseudomonas. Total N and Organic matter content in Yellow Sea of South Korea were relatively high. The Total-N content in the sediments
was varied from 177.31 to 1974.96 (mg/kg) and organic matter ranged from 0.82 to 4.23 (g/100 g −1). The current research work provides clear explanation obtained for the phylogenetic affiliation of the culturable bacterial
community in sediments of South Korean Yellow Sea and revealed the relationship with biogeochemical characteristics of the
sediments. 相似文献
20.
Bacterial and archaeal diversity in surface soils of three coal-fire vents was investigated by T-RFLP analysis and clone libraries of 16S rRNA genes. Soil analysis showed that underground coal fires significantly influenced soil pH, moisture and NO 3 ? content but had little effect on other elements, organic matter and available nutrients. Hierarchical cluster analysis showed that bacterial community patterns in the soils were very similar, but abundance varied with geographic distance. A clone library from one soil showed that the bacterial community was mainly composed of Firmicutes, Proteobacteria, Acidobacteria, Bacteroidetes, Planctomycetes, Actinobacteria, and unidentified groups. Of these, Firmicutes was the most abundant, accounting for 71.4 % of the clones, and was mainly represented by the genera Bacillus and Paenibacillus. Archaeal phylotypes were closely related to uncultivated species of the phyla Crenarchaeota (97.9 % of clones) and Thaumarchaeota (2.1 %). About 28 % of archaeal phylotypes were associated with ammonia oxidization, especially phylotypes that were highly related to a novel, ammonia-oxidizing isolate from the phylum Thaumarchaeota. These results suggested that microbial communities in the soils were diverse and might contain a large number of novel cultivable species with the potential to assimilate materials by heterotrophic metabolism at high temperature. 相似文献
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