scholarly journals Selective bacterial colonization processes on polyethylene waste samples in an abandoned landfill site

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Edoardo Puglisi ◽  
Francesco Romaniello ◽  
Serena Galletti ◽  
Enrico Boccaleri ◽  
Alberto Frache ◽  
...  
Keyword(s):  
Bacterial Communities ◽  
Bacterial Colonization ◽  
Chemical Properties ◽  
Microbial Colonization ◽  
Β Diversity ◽  
Physico Chemical ◽  
Plastic Type ◽  
Plastic Wastes ◽  
Ft Raman Spectroscopy ◽  
Degradation Degree

Abstract The microbial colonization of plastic wastes has been extensively studied in marine environments, while studies on aged terrestrial wastes are scarce, and mostly limited to the isolation of plastic-degrading microorganisms. Here we have applied a multidisciplinary approach involving culturomics, next-generation sequencing analyses and fine-scale physico-chemical measurements to characterize plastic wastes retrieved in landfill abandoned for more than 35 years, and to assess the composition of bacterial communities thriving as biofilms on the films’ surfaces. All samples were characterized by different colors but were all of polyethylene; IR and DSC analyses identified different level of degradation, while FT-Raman spectroscopy and X-ray fluorescence further assessed the degradation level and the presence of pigments. Each plastic type harbored distinct bacterial communities from the others, in agreement with the differences highlighted by the physico-chemical analyses. Furthermore, the most degraded polyethylene films were found to host a bacterial community more similar to the surrounding soil as revealed by both α- and β-diversity NGS analyses. This work confirms the novel hypothesis that different polyethylene terrestrial waste samples select for different bacterial communities, and that structure of these communities can be correlated with physico-chemical properties of the plastics, including the degradation degree.

scholarly journals Bacterial colonization and succession in a newly opened hospital

2017 ◽  
Vol 9 (391) ◽  
pp. eaah6500 ◽  
Author(s):  
Simon Lax ◽  
Naseer Sangwan ◽  
Daniel Smith ◽  
Peter Larsen ◽  
Kim M. Handley ◽  
...  
Keyword(s):  
Community Structure ◽  
Bacterial Communities ◽  
Bacterial Colonization ◽  
Dynamic Bayesian Network ◽  
Hospital Staff ◽  
Hospital Environment ◽  
Temporal Correlations ◽  
Β Diversity ◽  
Bacterial Dynamics ◽  
Surgical Recovery

The microorganisms that inhabit hospitals may influence patient recovery and outcome, although the complexity and diversity of these bacterial communities can confound our ability to focus on potential pathogens in isolation. To develop a community-level understanding of how microorganisms colonize and move through the hospital environment, we characterized the bacterial dynamics among hospital surfaces, patients, and staff over the course of 1 year as a new hospital became operational. The bacteria in patient rooms, particularly on bedrails, consistently resembled the skin microbiota of the patient occupying the room. Bacterial communities on patients and room surfaces became increasingly similar over the course of a patient’s stay. Temporal correlations in community structure demonstrated that patients initially acquired room-associated taxa that predated their stay but that their own microbial signatures began to influence the room community structure over time. The α- and β-diversity of patient skin samples were only weakly or nonsignificantly associated with clinical factors such as chemotherapy, antibiotic usage, and surgical recovery, and no factor except for ambulatory status affected microbial similarity between the microbiotas of a patient and their room. Metagenomic analyses revealed that genes conferring antimicrobial resistance were consistently more abundant on room surfaces than on the skin of the patients inhabiting those rooms. In addition, persistent unique genotypes ofStaphylococcusandPropionibacteriumwere identified. Dynamic Bayesian network analysis suggested that hospital staff were more likely to be a source of bacteria on the skin of patients than the reverse but that there were no universal patterns of transmission across patient rooms.

scholarly journals DIVERSITY AND SIMILARITY AMONG CYANOBACTERIA ASSEMBLAGES FROM SELECTED AQUATIC ECOSYSTEMS IN SARAWAK USING β –INDICES

2016 ◽  
Vol 1 (1) ◽  
pp. 28-37
Author(s):  
Mohd Nasarudin Harith ◽  
Ruhana Hassan
Keyword(s):  
Aquatic Ecosystem ◽  
Aquatic Ecosystems ◽  
Chemical Properties ◽  
Artificial Lake ◽  
Environmental Characteristics ◽  
Β Diversity ◽  
Physico Chemical ◽  
Wide Range ◽  
Aquaculture Ponds

A study was carried out to evaluate the diversity and similarity of cyanobacterial populations in selected Sarawak aquatic ecosystem using β-indices. Eight stations including aquaculture ponds, cage cultures, waterfall and artificial lake located in Serian, Bau and Batang Ai areas were selected. A total of 43 species belonging to 30 genera of cyanobacteria were recorded. The most distributed pattern among all sampling stations belongs to the genera Chroococcus, Lyngbya, Nostoc and Oscillatoria. The highest β diversity values were found among non-contiguous stations. Besides, no identical or totally different cyanobacteria diversity values were obtained among those non-contiguous stations. The highest β diversity value (0.84) was found among stations with contrasting environmental characteristics. The wide range of β-diversity and similarity suggested that different locations and types of aquatic ecosystems may have variations in physico-chemical properties of the water and eventually lead to the different composition of cyanobacteria.

scholarly journals Relationships between soil physico-chemical properties and total viable bacterial counts in Sunderban mangrove forests, Bangladesh

2012 ◽  
Vol 21 (2) ◽  
pp. 169-175 ◽  
Author(s):  
Mohammad Zabed Hossain ◽  
Chaman Binta Aziz ◽  
Mihir Lal Saha
Keyword(s):  
Nitrogen Content ◽  
Total Nitrogen ◽  
Bacterial Communities ◽  
Chemical Properties ◽  
Total Nitrogen Content ◽  
Mangrove Forests ◽  
Bacterial Colony ◽  
Soil Bacterial Communities ◽  
Physico Chemical ◽  
Soil Bacterial

Although soil bacterial communities are one of the important biotic components that influence decomposition and nutrient mineralization in the terrestrial ecosystems, factors driving this biotic community in the Sunderban mangrove forests are not well studied. The present study examined the importance of soil physico?chemical properties in driving soil bacterial communities in the Sunderban mangrove forests, Bangladesh. Soils were collected from 12 locations under four sites, namely Koromjal, Kotka, Hironpoint, and Dublarchar of Sunderban forests. Results showed a large range of variation in total bacterial colony counts (7.65 × 104 ? 14.5 × 104 cfu/g soil), soil moisture (9.0 ? 27.0%), total nitrogen (0.057 ? 0.158%), available nitrogen (0.504 ? 2.016 ?g/g soil), soil salinity (20.99 ? 34.99 mg chloride/g soil), and organic carbon (0.460 ? 0.885%). Data of the present study revealed that the number of total viable bacterial count was significantly and positively correlated only with total nitrogen content in soil indicating that total nitrogen content is the major driving factor of bacterial communities in the Sunderban mangrove forest soils.DOI: http://dx.doi.org/10.3329/dujbs.v21i2.11515 Dhaka Univ. J. Biol. Sci. 21(2): 169-175, 2012 (July)

scholarly journals Effect of polymer type on the colonization of plastic pellets by marine bacteria

2021 ◽  
Vol 368 (5) ◽  
Author(s):  
Josefine Hansen ◽  
Jette Melchiorsen ◽  
Nicole Ciacotich ◽  
Lone Gram ◽  
Eva C Sonnenschein
Keyword(s):  
Bacterial Colonization ◽  
Amplicon Sequencing ◽  
Bacterial Biofilm ◽  
Microbial Colonization ◽  
Natural Seawater ◽  
Bacterial Strains ◽  
Initial Inoculum ◽  
Plastic Type ◽  
Polymer Type ◽  
Hydrocarbon Degraders

Abstract Plastic is omnipresent in the oceans and serves as a surface for biofilm-forming microorganisms. Plastic debris comprises different polymers, which may influence microbial colonization; here, we evaluated whether polymer type affects bacterial biofilm formation. Quantifying the biofilm on polyethylene (PE), polypropylene (PP) or polystyrene (PS) pellets by six marine bacterial strains (Vibrio,Pseudoalteromonas,Phaeobacter) demonstrated that each strain had a unique colonization behavior with either a preference for PS or PP over the other polymer types or no preference for a specific plastic type. PE, PP and PS pellets were exposed to natural seawater microbiota using free-living or total communities as inoculum. Microbial assembly as determined by 16S rRNA (V4) amplicon sequencing was affected by the composition of the initial inoculum and also by the plastic type. Known polymer and hydrocarbon degraders such as Paraglaciecola, Oleibacter and Hydrogenophaga were found in the plastic biofilms. Thus, on a community level, bacterial colonization on plastic is influenced by the microorganisms as well as the polymer type, and also individual strains can demonstrate polymer-specific colonization.

scholarly journals Differential microbial assemblages associated with shikonin-producing Borage species in two distinct soil types

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Aliya Fazal ◽  
Minkai Yang ◽  
Zhongling Wen ◽  
Farman Ali ◽  
Ran Ren ◽  
...  
Keyword(s):  
Chemical Properties ◽  
Microbial Colonization ◽  
Fine Tuning ◽  
Soil Types ◽  
Natural Soil ◽  
Β Diversity ◽  
Pharmacological Potential ◽  
Main Components ◽  
Physical And Chemical ◽  
Properties Of Soil

AbstractShikonin and its derivatives are the main components of traditional Chinese medicine, Zicao. The pharmacological potential of shikonin and its derivatives have been extensively studied. Yet, less is known about the microbial assemblages associated with shikonin producing Borage plants. We studied microbial profiles of two Borage species, Echium plantagineum (EP) and Lithospermum erythrorhizon (LE), to identify the dynamics of microbial colonization pattern within three rhizo-compatments and two distinct soil types. Results of α and β-diversity via PacBio sequencing revealed significantly higher microbial richness and diversity in the natural soil along with a decreasing microbial gradient across rhizosphere to endosphere. Our results displayed genotype and soil type–dependent fine-tuning of microbial profiles. The host plant was found to exert effects on the physical and chemical properties of soil, resulting in reproducibly different micro-biota. Analysis of differentially abundant microbial OTUs displayed Planctomycetes and Bacteroidetes to be specifically enriched in EP and LE rhizosphere while endosphere was mostly prevailed by Cyanobacteria. Network analysis to unfold co-existing microbial species displayed different types of positive and negative interactions within different communities. The data provided here will help to identify microbes associated with different rhizo-compartments of potential host plants. In the future, this might be helpful for manipulating the keystone microbes for ecosystem functioning.

scholarly journals Metagenomic Analysis of Bacterial Communities in Agricultural Soils from Vietnam with Special Attention to Phosphate Solubilizing Bacteria

2021 ◽  
Vol 9 (9) ◽  
pp. 1796
Author(s):  
Anna Hegyi ◽  
Tran Bao Khuyen Nguyen ◽  
Katalin Posta
Keyword(s):  
Bacterial Communities ◽  
Phosphate Solubilization ◽  
Negative Relationship ◽  
Chemical Properties ◽  
Rrna Gene ◽  
P Availability ◽  
Phosphate Solubilizing Bacteria ◽  
Bacterial Phyla ◽  
Physico Chemical ◽  
Phosphate Solubilizing

Bacterial communities can promote increased phosphorus (P) availability for plants and microbes in soil via various mechanisms of phosphate solubilization. The production of extracellular phosphatases releases available P through the hydrolysis of organic P. Examining the abundance and diversity of the bacterial community, including phosphate solubilizing bacteria in soil, may provide valuable information to overcome P scarcity in soil ecosystems. Here, the diversity and relative abundance of bacterial phyla and genera of six agricultural soil samples from Vietnam were analysed by next generation sequencing of the 16S rRNA gene. Phosphatase activities of each soil were compared with physico-chemical parameters and the abundance of the alkaline phosphatase gene phoD. We showed the dominance of Chloroflexi, Proteobacteria, Actinobacteria, Acidobacteria and Firmicutes. Total nitrogen positively correlated with phyla Proteobacteria, Acidobacteria, Firmicutes and Planctomycetes. The abundance of several genera of Proteobacteria showed positive relationship with the copy number of the phoD gene. The abundance of several taxa positively correlated with silt content, while a negative relationship of Proteobacteria was found with sand content. Our results demonstrated the clear influence of soil physico-chemical properties on the abundance of various bacterial taxa including those potentially involved in phosphate solubilization.

scholarly journals Chytrid fungi shape bacterial communities on model particulate organic matter

2020 ◽  
Vol 16 (9) ◽  
pp. 20200368
Author(s):  
Cordelia Roberts ◽  
Ro Allen ◽  
Kimberley E. Bird ◽  
Michael Cunliffe
Keyword(s):  
Organic Matter ◽  
Particulate Organic Matter ◽  
Bacterial Communities ◽  
Aquatic Ecosystems ◽  
Bacterial Colonization ◽  
Community Diversity ◽  
Microbial Colonization ◽  
Chytrid Fungus ◽  
Associated Bacteria ◽  
And Function

Microbial colonization and degradation of particulate organic matter (POM) are important processes that influence the structure and function of aquatic ecosystems. Although POM is readily used by aquatic fungi and bacteria, there is a limited understanding of POM-associated interactions between these taxa, particularly for early-diverging fungal lineages. Using a model ecological system with the chitin-degrading freshwater chytrid fungus Rhizoclosmatium globosum and chitin microbeads, we assessed the impacts of chytrid fungi on POM-associated bacteria. We show that the presence of chytrids on POM alters concomitant bacterial community diversity and structure, including differing responses between chytrid life stages. We propose that chytrids can act as ecosystem facilitators through saprotrophic feeding by producing ‘public goods’ from POM degradation that modify bacterial POM communities. This study suggests that chytrid fungi have complex ecological roles in aquatic POM degradation not previously considered, including the regulation of bacterial colonization, community succession and subsequent biogeochemical potential.

scholarly journals Differential Microbial Assemblages Associated with Shikonin-producing Borage Species in Two Distinct Soil Types

2021 ◽  
Author(s):  
Aliya Fazal ◽  
Minkai Yang ◽  
Zhongling Wen ◽  
Farman Ali ◽  
Ran Ren ◽  
...  
Keyword(s):  
Chemical Properties ◽  
Microbial Colonization ◽  
Fine Tuning ◽  
Soil Types ◽  
Natural Soil ◽  
Β Diversity ◽  
Pharmacological Potential ◽  
Main Components ◽  
Physical And Chemical ◽  
Properties Of Soil

Abstract Shikonin and its derivatives are the main components of traditional Chinese medicine, Zicao. The pharmacological potential of shikonin and its derivatives have been extensively studied. Yet, less is known about the microbial assemblages associated with shikonin producing Borage plants. We studied microbial profiles of two Borage species, Echium plantagineum (EP) and Lithospermum erythrorhizon (LE), to identify the dynamics of microbial colonization pattern within three rhizo-compatments and two distinct soil types. Results of α and β-diversity via PacBio sequencing revealed significantly higher microbial richness and diversity in the natural soil along with a decreasing microbial gradient across rhizosphere to endosphere. Our results displayed genotype and soil type–dependent fine-tuning of microbial profiles. The host plant was found to exert effects on the physical and chemical properties of soil, resulting in reproducibly different micro-biota. Analysis of differentially abundant microbial OTUs displayed, Planctomycetes and Bacteroidetes to be specifically enriched in EP and LE rhizosphere while endosphere was mostly prevailed by Cyanobacteria. Network analysis to unfold co-existing microbial species displayed different types of positive and negative interactions within different communities. The baseline data provided here will help to identify microbes associated with different rhizo-compartments of potential host plants. In the future, this might be helpful for manipulating the keystone microbes for ecosystem functioning.

Decoration of specific sites on freeze-fractured membranes

1978 ◽  
Vol 36 (2) ◽  
pp. 140-141
Author(s):  
H. Gross ◽  
H. Moor
Keyword(s):  
Pure Water ◽  
Freeze Fracture ◽  
Chemical Properties ◽  
Surface Forces ◽  
Sulfate Pentahydrate ◽  
Copper Sulfate Pentahydrate ◽  
Physico Chemical ◽  
Water Of Hydration ◽  
Small Container ◽  
Binding Forces

Fracturing under ultrahigh vacuum (UHV, p ≤ 10-9 Torr) produces membrane fracture faces devoid of contamination. Such clean surfaces are a prerequisite foe studies of interactions between condensing molecules is possible and surface forces are unequally distributed, the condensate will accumulate at places with high binding forces; crystallites will arise which may be useful a probes for surface sites with specific physico-chemical properties. Specific “decoration” with crystallites can be achieved nby exposing membrane fracture faces to water vopour. A device was developed which enables the production of pure water vapour and the controlled variation of its partial pressure in an UHV freeze-fracture apparatus (Fig.1a). Under vaccum (≤ 10-3 Torr), small container filled with copper-sulfate-pentahydrate is heated with a heating coil, with the temperature controlled by means of a thermocouple. The water of hydration thereby released enters a storage vessel.

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