Isolation, Characterization and Community Diversity of Indigenous Putative Toluene-Degrading Bacterial Populations with Catechol-2,3-Dioxygenase Genes in Contaminated Soils

Abstract Terminal restriction fragment length polymorphism was used to determine the bacterial community diversity in crop rotations with different proportion of cereals (40%, 60% and 80%) and various fertilisation treatments (F1 - mineral fertiliser amendment + the application of organic fertiliser Veget® and F2 - mineral fertilisation) sampled on two dates (July and October 2012). No statistically significant differences in the number of terminal restriction fragments were detected by Fisher´s least significant difference between two types of fertilisation or among samples with different proportion of cereals. In contrast, statistically significant differences were detected between samples collected in July and October, when in October there was a 43.5% reduction in the number of bacterial species in comparison with July. Principal component analysis as well as cluster analysis showed that a higher similarity in composition of bacterial communities was present among all soil samples collected in July and two samples collected in October. Other samples collected in October were separated from each other. The results of this study demonstrated that bacteria abundance and community composition were not affected by the proportion of cereals and fertiliser used.

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RHIZODEGRADATION OF PHENANTHRENE, ANTHRACENE AND PYRENE BY AUGMENTING BACILLUS CEREUS AND BACILLUS SUBTILIS STRAINS

International Journal of Advanced Research ◽

10.21474/ijar01/12422 ◽

2021 ◽

Vol 9 (02) ◽

pp. 89-96

Author(s):

M. Poornachander Rao ◽

◽

Anitha Yerra ◽

K. Satyaprasad ◽

◽

...

Keyword(s):

Bacillus Subtilis ◽

Bacillus Cereus ◽

Contaminated Soils ◽

Rhizosphere Soil ◽

Culture Method ◽

Experimental Period ◽

Bacterial Strains ◽

Bacterial Populations ◽

Metabolic Activities ◽

Pot Culture

Rhizodegradation is one of the best methods for the effective removal of dangerous polycyclic aromatic hydrocarbons pollutants from soil. This is operative due to the high persistent, non-bioavailability nature of PAHs and combined, sequential reactions of bacteria present in rhizosphere of plants. We have conducted pot-culture method to study the degradation of three PAHs compounds namely phenanthrene, anthracene and pyrene in artificially contaminated soils of rhizosphere and non-rhizosphere soil treatments of blackgram(Vignamungo L.) that augmented by two potential PAHs degraders namely Bacillus cereus CPOU13 and Bacillus subtilis SPC14 isolated from naturally contaminated soils for 90days. HPLC studies revealed that degradation percentages of the three PAHs in treatments were more where selected strains augmented to the soil treatments over the non-augmented soils. The rhizosphere treatments that have augmented strains recorded more degradation percentages of phenanthrene, anthracene and pyrene over the rhizosphere treatments that were non-augmented. Pyrene, a high molecular weight PAHs degraded maximum to 96.24% in rhizosphere soil treatment that is augmented with the strains while moderate degradation of pyrene recorded in non-autoclaved soil treatments that contain natural microbial communities. The study of counting of bacterial populations during the experimental period revealed that the populations of the selected and other natural bacteria were gradually increased from the first day, reached maximum by 60days and became almost consistent in 90days in all the treatments. It was also observed that the populations of bacteria were high in rhizosphere treatments compared to the non-rhizosphere soil treatments. With these results it has been predicted that degradation of PAHs in rhizosphere soil treatments is closely associated with the increasing PAHs degrading bacterial populations of selected bacterial strains that may consume more quantity of PAHs for their metabolic activities in rhizosphere soils. Key words: Rhizodegradation, PAHs, HPLC, pot culture.

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Fungal Community Diversity of a Heavy Metal Contaminated Soils Revealed by Metagenomics

10.21203/rs.3.rs-730302/v1 ◽

2021 ◽

Author(s):

Michel Rodrigo Zambrano Passarini ◽

Júlia Ronzella Ottoni ◽

Paulo Emílio Santos Costa ◽

Denise Cavalvante Hissa ◽

Raul Maia Falcão ◽

...

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Contaminated Soils ◽

Heavy Metal Contamination ◽

Community Diversity ◽

Fungal Communities ◽

Contaminated Sites ◽

Contaminated Site ◽

Toxic Compounds ◽

Metagenomic Approach

Abstract The inappropriate disposal of toxic compounds generated by industrial activity has been impacting to the environment considerably. Microbial communities inhabiting contaminated sites may represent interesting ecological alternatives for the decontamination of environments. The present work aimed to investigate the fungal diversity inhabiting sediments from industrial waste containing heavy metals by using metagenomic approach. A total of twelve fungal orders were retrieved from datasets and, at phylum level, Ascomycota was the most abundant, followed by Basidiomycota, Chytridiomycota and Blastocladiomycota. Higher abundance of sequences was encountered within the less contaminated site, while the lower abundance was found in the sample with the higher contamination with lead. Gene sequences related to DNA repair and heavy metals biosorption processes were found in the four samples analyzed. The genera Aspergillus and Chaetomium, and Saccharomycetales order were highly present within all samples, showing their potential to be used for bioremediation studies. The present work demonstrated the importance of using the metagenomic approach to understand the dynamics of fungal communities and their behavior under heavy metal contamination, aiming the use in bioremediation processes of environments contaminated with heavy metals.

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Inoculation of Pseudomonas sp. GHD-4 and mushroom residue carrier increased the soil enzyme activities and microbial community diversity in Pb-contaminated soils

Journal of Soils and Sediments ◽

10.1007/s11368-018-2111-3 ◽

2018 ◽

Vol 19 (3) ◽

pp. 1064-1076 ◽

Cited By ~ 6

Author(s):

Sumei Yu ◽

Xin Bai ◽

Jinsong Liang ◽

Yingnan Wei ◽

Siqi Huang ◽

...

Keyword(s):

Microbial Community ◽

Enzyme Activities ◽

Contaminated Soils ◽

Soil Enzyme ◽

Community Diversity ◽

Pseudomonas Sp ◽

Soil Enzyme Activities ◽

Microbial Community Diversity

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Metagenomics Reveals Pervasive Bacterial Populations and Reduced Community Diversity across the Alaska Tundra Ecosystem

Frontiers in Microbiology ◽

10.3389/fmicb.2016.00579 ◽

2016 ◽

Vol 7 ◽

Cited By ~ 29

Author(s):

Eric R. Johnston ◽

Luis M. Rodriguez-R ◽

Chengwei Luo ◽

Mengting M. Yuan ◽

Liyou Wu ◽

...

Keyword(s):

Community Diversity ◽

Bacterial Populations ◽

Tundra Ecosystem

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Environment Gradient related Dissimilatory Nitrate Reduction to Ammonium in Huangmao Sea Estuary: Rates and Community Diversity

10.5194/bg-2019-31 ◽

2019 ◽

Cited By ~ 1

Author(s):

Ran Jiang ◽

Shu-Xin Zhang ◽

Gou Wei ◽

Rui He ◽

Li-Ling Yang ◽

...

Keyword(s):

Nitrate Reduction ◽

River Estuary ◽

Pearl River Estuary ◽

Community Diversity ◽

Pearl River ◽

Bacterial Populations ◽

Dissimilatory Nitrate Reduction ◽

The Pearl River ◽

One Year

Abstract. The potential rates of dissimilatory nitrate reduction to ammonium (DNRA) in the sediments collected from Huangmao Sea Estuary (HSE), one of Pearl River Estuaries in China, were investigated. The research covers a one-year period at 20 sites of HSE based on the 15N isotope and molecular biology analysis. The results showed that the environment gradients of nitrogen pollutants decreased from the estuary to the sea, and the characteristics of terrestrial pollutant export were obvious. 15NH4+ was detected in all sites in continuous-flow systems, which showed that DNRA existed in HSE potentially. In which the maximum 15NH4+ was 1948.5 μg/L, accordingly in situ rate of DNRA was 6.3 μg/L.h in 72 h. The high transcripts of nrfA gene were found at the same site, with values of 1 159 715 copics/(g wet sediment). Correspondingly, a very low transcripts of nrfA were found at other sites. Principal components analysis (PCA) based on community composition at genus level showed the distribution pattern of the nrfA gene sequences. Nine samples formed three distinct clusters, corresponding to their geographical locations, which suggested that salinity was likely to affect the selection of the nrfA bacterial populations. This study provide a better understanding of DNRA in the Pearl River Estuary.

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