scholarly journals Bacterial Community Response to Petroleum Hydrocarbon Amendments in Freshwater, Marine, and Hypersaline Water-Containing Microcosms

2013 ◽  
Vol 79 (19) ◽  
pp. 5927-5935 ◽  
Author(s):  
Diogo Jurelevicius ◽  
Vanessa Marques Alvarez ◽  
Joana Montezano Marques ◽  
Laryssa Ribeiro Fonseca de Sousa Lima ◽  
Felipe de Almeida Dias ◽  
...  
Keyword(s):  
Bacterial Communities ◽  
Aquatic Ecosystems ◽  
Petroleum Hydrocarbon ◽  
Rna Extraction ◽  
Community Response ◽  
Hydrocarbon Contamination ◽  
Clone Libraries ◽  
Content Type ◽  
Hypersaline Water ◽  
General Response

ABSTRACTHydrocarbon-degrading bacterial communities from freshwater, marine, and hypersaline Brazilian aquatic ecosystems (with water salinities corresponding to 0.2%, 4%, and 5%, respectively) were enriched with different hydrocarbons (heptadecane, naphthalene, or crude oil). Changes within the different microcosms of bacterial communities were analyzed using cultivation approaches and molecular methods (DNA and RNA extraction, followed by genetic fingerprinting and analyses of clone libraries based on the 16S rRNA-coding gene). A redundancy analysis (RDA) of the genetic fingerprint data and a principal component analysis (PCA) of the clone libraries revealed hydrocarbon-enriched bacterial communities specific for each ecosystem studied. However, within the same ecosystem, different bacterial communities were selected according to the petroleum hydrocarbon used. In general, the results demonstrated thatAcinetobacterandCloacibacteriumwere the dominant genera in freshwater microcosms; theOceanospirillalesorder and theMarinobacter,Pseudomonas, andCycloclasticusgenera predominated in marine microcosms; and theOceanospirillalesorder and theMarinobactergenus were selected in the different hydrocarbon-containing microcosms in hypersaline water. Determination of total petroleum hydrocarbons (TPHs) in all microcosms after 32 days of incubation showed a decrease in the hydrocarbon concentration compared to that for the controls. A total of 50 (41.3%) isolates from the different hydrocarbon-contaminated microcosms were associated with the dominant operational taxonomic units (OTUs) obtained from the clone libraries, and their growth in the hydrocarbon contaminating the microcosm from which they were isolated as the sole carbon source was observed. These data provide insight into the general response of bacterial communities from freshwater, marine, and hypersaline aquatic ecosystems to petroleum hydrocarbon contamination.

scholarly journals Selection for Cu-Tolerant Bacterial Communities with Altered Composition, but Unaltered Richness, via Long-Term Cu Exposure

2012 ◽  
Vol 78 (20) ◽  
pp. 7438-7446 ◽  
Author(s):  
Jeanette Berg ◽  
Kristian K. Brandt ◽  
Waleed A. Al-Soud ◽  
Peter E. Holm ◽  
Lars H. Hansen ◽  
...  
Keyword(s):  
Bacterial Communities ◽  
Metal Tolerance ◽  
Bacterial Community Composition ◽  
Community Response ◽  
Leucine Incorporation ◽  
Rrna Gene ◽  
Sequence Information ◽  
Content Type ◽  
Relative Abundances ◽  
The Impact

ABSTRACTToxic metal pollution affects the composition and metal tolerance of soil bacterial communities. However, there is virtually no knowledge concerning the responses of members of specific bacterial taxa (e.g., phyla or classes) to metal toxicity, and contradictory results have been obtained regarding the impact of metals on operational taxonomic unit (OTU) richness. We used tag-coded pyrosequencing of the 16S rRNA gene to elucidate the impacts of copper (Cu) on bacterial community composition and diversity within a well-described Cu gradient (20 to 3,537 μg g−1) stemming from industrial contamination with CuSO4more than 85 years ago. DNA sequence information was linked to analysis of pollution-induced community tolerance (PICT) to Cu, as determined by the [3H]leucine incorporation technique, and to chemical characterization of the soil. PICT was significantly correlated to bioavailable Cu, as determined by the results seen with a Cu-specific bioluminescent biosensor strain, demonstrating a specific community response to Cu. The relative abundances of members of several phyla or candidate phyla, including theProteobacteria,Bacteroidetes,Verrumicrobia,Chloroflexi,WS3, andPlanctomycetes, decreased with increasing bioavailable Cu, while members of the dominant phylum, theActinobacteria, showed no response and members of theAcidobacteriashowed a marked increase in abundance. Interestingly, changes in the relative abundances of classes frequently deviated from the responses of the phyla to which they belong. Despite the apparent Cu impacts on Cu resistance and community structure, bioavailable Cu levels did not show any correlation to bacterial OTU richness (97% similarity level). Our report highlights several bacterial taxa responding to Cu and thereby provides new guidelines for future studies aiming to explore the bacterial domain for members of metal-responding taxa.

scholarly journals Characterization of microbial response to petroleum hydrocarbon contamination in a lacustrine ecosystem

2021 ◽  
Author(s):  
Emilio D’Ugo ◽  
Milena Bruno ◽  
Arghya Mukherjee ◽  
Dhrubajyoti Chattopadhyay ◽  
Roberto Giuseppetti ◽  
...  
Keyword(s):  
Oil Spill ◽  
Petroleum Hydrocarbon ◽  
Oil Spills ◽  
Oil Pollution ◽  
Primary Source ◽  
Hydrocarbon Contamination ◽  
Petroleum Hydrocarbon Contamination ◽  
Microbial Response ◽  
Pollution Event ◽  
Hydrocarbonoclastic Potential

AbstractMicrobiomes of freshwater basins intended for human use remain poorly studied, with very little known about the microbial response to in situ oil spills. Lake Pertusillo is an artificial freshwater reservoir in Basilicata, Italy, and serves as the primary source of drinking water for more than one and a half million people in the region. Notably, it is located in close proximity to one of the largest oil extraction plants in Europe. The lake suffered a major oil spill in 2017, where approximately 400 tons of crude oil spilled into the lake; importantly, the pollution event provided a rare opportunity to study how the lacustrine microbiome responds to petroleum hydrocarbon contamination. Water samples were collected from Lake Pertusillo 10 months prior to and 3 months after the accident. The presence of hydrocarbons was verified and the taxonomic and functional aspects of the lake microbiome were assessed. The analysis revealed specialized successional patterns of lake microbial communities that were potentially capable of degrading complex, recalcitrant hydrocarbons, including aromatic, chloroaromatic, nitroaromatic, and sulfur containing aromatic hydrocarbons. Our findings indicated that changes in the freshwater microbial community were associated with the oil pollution event, where microbial patterns identified in the lacustrine microbiome 3 months after the oil spill were representative of its hydrocarbonoclastic potential and may serve as effective proxies for lacustrine oil pollution.

scholarly journals Oral Bacterial Communities in Individuals with Type 2 Diabetes Who Live in Southern Thailand

2013 ◽  
Vol 80 (2) ◽  
pp. 662-671 ◽  
Author(s):  
Kanokporn Kampoo ◽  
Rawee Teanpaisan ◽  
Ruth G. Ledder ◽  
Andrew J. McBain
Keyword(s):  
Type 2 Diabetes ◽  
Dental Caries ◽  
Bacterial Communities ◽  
Glycosylated Hemoglobin ◽  
Content Type ◽  
Supragingival Plaque ◽  
Southern Thailand ◽  
Acid Tolerant ◽  
Dna Profiles

ABSTRACTType 2 diabetes mellitus is increasingly common in Thailand and elsewhere. In the present investigation, the bacteriological composition of saliva and supragingival plaque in Thai diabetics with and without active dental caries and in nondiabetics was determined by differential culture and eubacterial DNA profiling. Potential associations between fasting blood sugar and glycosylated hemoglobin (biomarkers of current and historical glucose control, respectively) with decayed, missing, and filled teeth and with salivaryStreptococcusandLactobacilluscounts were also investigated. The incidence of active dental caries was greater in the Thai diabetics than in nondiabetics, and the numbers of total streptococci and lactobacilli were significantly higher in supragingival plaque from diabetics than in nondiabetics.Lactobacilluscounts in the saliva and supragingival plaque of diabetics with active caries were significantly higher than those in diabetics without active caries. Oral eubacterial DNA profiles of diabetic versus nondiabetic individuals and of diabetics with active caries versus those without active caries could not be readily differentiated through cluster analysis or multidimensional scaling. The elevated caries incidence in the Thai diabetics was positively associated with numbers of bacteria of the acidogenic/acid-tolerant generaStreptococcusandLactobacillus. Lactobacillusbacterial numbers were further elevated in diabetics with active caries, although salivary eubacterial DNA profiles were not significantly altered.

scholarly journals Downregulation of the Central Noradrenergic System by Toxoplasma gondii Infection

2018 ◽  
Vol 87 (2) ◽  
Author(s):  
Isra Alsaady ◽  
Ellen Tedford ◽  
Mohammad Alsaad ◽  
Greg Bristow ◽  
Shivali Kohli ◽  
...  
Keyword(s):  
Toxoplasma Gondii ◽  
Infection Intensity ◽  
Noradrenergic System ◽  
Neural Cells ◽  
Mrna Levels ◽  
Female Rat ◽  
Motor Impairments ◽  
Content Type ◽  
General Response

ABSTRACT Toxoplasma gondii is associated with physiological effects in the host. Dysregulation of catecholamines in the central nervous system has previously been observed in chronically infected animals. In the study described here, the noradrenergic system was found to be suppressed with decreased levels of norepinephrine (NE) in brains of infected animals and in infected human and rat neural cells in vitro. The mechanism responsible for the NE suppression was found to be downregulation of dopamine β-hydroxylase (DBH) gene expression, encoding the enzyme that synthesizes norepinephrine from dopamine, with downregulation observed in vitro and in infected brain tissue, particularly in the dorsal locus coeruleus/pons region. The downregulation was sex specific, with males expressing reduced DBH mRNA levels whereas females were unchanged. Rather, DBH expression correlated with estrogen receptor in the female rat brains for this estrogen-regulated gene. DBH silencing was not a general response of neurons to infection, as human cytomegalovirus did not downregulate DBH expression. The noradrenergic-linked behaviors of sociability and arousal were altered in chronically infected animals, with a high correlation between DBH expression and infection intensity. A decrease in DBH expression in noradrenergic neurons can elevate dopamine levels, which provides a possible explanation for mixed observations of changes in this neurotransmitter with infection. Decreased NE is consistent with the loss of coordination and motor impairments associated with toxoplasmosis. Further, the altered norepinephrine synthesis observed here may, in part, explain behavioral effects of infection and associations with mental illness.

scholarly journals Complete Genome Sequence of the Hydrocarbon-Degrading Strain Achromobacter sp. B7, Isolated during Petroleum Hydrocarbon Bioremediation in the Valparaiso Region, Chile

2018 ◽  
Vol 7 (19) ◽  
Author(s):  
Valentina Méndez ◽  
Lisette Hernández ◽  
Francisco Salvà-Serra ◽  
Daniel Jaén-Luchoro ◽  
Roberto E. Durán ◽  
...  
Keyword(s):  
Genome Sequence ◽  
Complete Genome Sequence ◽  
Complete Genome ◽  
Petroleum Hydrocarbon ◽  
Polluted Soil ◽  
Content Type ◽  
Achromobacter Sp

Achromobacter sp. strain B7 (= CCUG 72081) was isolated from a diesel-polluted soil from the Valparaiso Region, Chile, subjected to bioremediation with a hydrocarbon-degrading enrichment.

scholarly journals Sponge-Associated Bacteria Are Strictly Maintained in Two Closely Related but Geographically Distant Sponge Hosts

2011 ◽  
Vol 77 (20) ◽  
pp. 7207-7216 ◽  
Author(s):  
Naomi F. Montalvo ◽  
Russell T. Hill
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Bacterial Communities ◽  
Sponge Species ◽  
Rrna Gene ◽  
Gene Sequences ◽  
Associated Bacteria ◽  
Content Type ◽  
Key Species ◽  
Sponge Associated Bacteria

ABSTRACTThe giant barrel spongesXestospongiamutaandXestospongiatestudinariaare ubiquitous in tropical reefs of the Atlantic and Pacific Oceans, respectively. They are key species in their respective environments and are hosts to diverse assemblages of bacteria. These two closely related sponges from different oceans provide a unique opportunity to examine the evolution of sponge-associated bacterial communities. Mitochondrial cytochrome oxidase subunit I gene sequences fromX.mutaandX.testudinariashowed little divergence between the two species. A detailed analysis of the bacterial communities associated with these sponges, comprising over 900 full-length 16S rRNA gene sequences, revealed remarkable similarity in the bacterial communities of the two species. Both sponge-associated communities include sequences found only in the twoXestospongiaspecies, as well as sequences found also in other sponge species and are dominated by three bacterial groups,Chloroflexi,Acidobacteria, andActinobacteria. While these groups consistently dominate the bacterial communities revealed by 16S rRNA gene-based analysis of sponge-associated bacteria, the depth of sequencing undertaken in this study revealed clades of bacteria specifically associated with each of the twoXestospongiaspecies, and also with the genusXestospongia, that have not been found associated with other sponge species or other ecosystems. This study, comparing the bacterial communities associated with closely related but geographically distant sponge hosts, gives new insight into the intimate relationships between marine sponges and some of their bacterial symbionts.

scholarly journals Linearmycins Activate a Two-Component Signaling System Involved in Bacterial Competition and Biofilm Morphology

2017 ◽  
Vol 199 (18) ◽  
Author(s):  
Reed M. Stubbendieck ◽  
Paul D. Straight
Keyword(s):  
Antibiotic Resistance ◽  
Abc Transporter ◽  
Bacterial Communities ◽  
Biofilm Formation ◽  
Bacterial Species ◽  
Bioactive Metabolites ◽  
Signaling System ◽  
Content Type ◽  
Two Component ◽  
Analytical Approaches

ABSTRACT Bacteria use two-component signaling systems to adapt and respond to their competitors and changing environments. For instance, competitor bacteria may produce antibiotics and other bioactive metabolites and sequester nutrients. To survive, some species of bacteria escape competition through antibiotic production, biofilm formation, or motility. Specialized metabolite production and biofilm formation are relatively well understood for bacterial species in isolation. How bacteria control these functions when competitors are present is not well studied. To address fundamental questions relating to the competitive mechanisms of different species, we have developed a model system using two species of soil bacteria, Bacillus subtilis and Streptomyces sp. strain Mg1. Using this model, we previously found that linearmycins produced by Streptomyces sp. strain Mg1 cause lysis of B. subtilis cells and degradation of colony matrix. We identified strains of B. subtilis with mutations in the two-component signaling system yfiJK operon that confer dual phenotypes of specific linearmycin resistance and biofilm morphology. We determined that expression of the ATP-binding cassette (ABC) transporter yfiLMN operon, particularly yfiM and yfiN, is necessary for biofilm morphology. Using transposon mutagenesis, we identified genes that are required for YfiLMN-mediated biofilm morphology, including several chaperones. Using transcriptional fusions, we found that YfiJ signaling is activated by linearmycins and other polyene metabolites. Finally, using a truncated YfiJ, we show that YfiJ requires its transmembrane domain to activate downstream signaling. Taken together, these results suggest coordinated dual antibiotic resistance and biofilm morphology by a single multifunctional ABC transporter promotes competitive fitness of B. subtilis. IMPORTANCE DNA sequencing approaches have revealed hitherto unexplored diversity of bacterial species in a wide variety of environments that includes the gastrointestinal tract of animals and the rhizosphere of plants. Interactions between different species in bacterial communities have impacts on our health and industry. However, many approaches currently used to study whole bacterial communities do not resolve mechanistic details of interspecies interactions, including how bacteria sense and respond to their competitors. Using a competition model, we have uncovered dual functions for a previously uncharacterized two-component signaling system involved in specific antibiotic resistance and biofilm morphology. Insights gleaned from signaling within interspecies interaction models build a more complete understanding of gene functions important for bacterial communities and will enhance community-level analytical approaches.

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