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Archives of Microbiology Jan 2022Oxytetracycline (OTC), is a widely used veterinary antibiotic for treatment and prophylaxis in aquaculture. As an emerging pollutant, OTC in the environment exerts...
Oxytetracycline (OTC), is a widely used veterinary antibiotic for treatment and prophylaxis in aquaculture. As an emerging pollutant, OTC in the environment exerts selective pressure on aquatic organisms causing proliferation of antibiotic resistant genes. In the present study, an OTC tolerant isolate labelled as pw2 was selected among the 11 OTC tolerant isolates, isolated from the aquaculture effluent, for investigating its OTC degrading potential. The cell morphology, biochemical characteristics, and 16S ribosomal RNA (rRNA) gene sequence of the isolated strain indicated that it belonged to the genus Planococcus. The OTC removal percentage was estimated through measuring its residual concentration in the culture medium with high performance liquid chromatography. The strain exhibited maximum removal efficiency of 90.62%, with initial OTC concentration of 10 µg/ml. The optimum degrading conditions were 35 °C and pH 7. The degradation rate of OTC with (biotic) and without strain pw2 (abiotic) was 3.253 and 1.149 mg/l/d, respectively. The half-life was recorded to be 2.13 d in the presence of strain pw2, in contrast to 6.03 days recorded without strain pw2. The total (biotic + abiotic) OTC degradation efficiency was 75.74, 83.93, 90.62, and 86.47% for the initial OTC concentrations of 1 to 25 µg/ml, respectively. Addition of carbon and nitrogen did not influence the OTC removal which indicates Planococcus sp. pw2 use OTC as sole energy source. Thus, Planococcus sp. pw2 plays a vital role in reducing the OTC concentration in the environment, offering a promising method for treatment of aquaculture effluent containing OTC.
Topics: Anti-Bacterial Agents; Aquaculture; Bacteria; Oxytetracycline; RNA, Ribosomal, 16S
PubMed: 34994864
DOI: 10.1007/s00203-021-02732-6 -
MicrobiologyOpen Jun 2020Strain Y74 was an isolate from the sandy soil in the town of Huatugou, Qinghai-Tibet Plateau, China. An analysis of this strain's phenotypic, chemotaxonomic, and genomic...
Strain Y74 was an isolate from the sandy soil in the town of Huatugou, Qinghai-Tibet Plateau, China. An analysis of this strain's phenotypic, chemotaxonomic, and genomic characteristics established the relationship of the isolate with the genus Planococcus. Strain Y74 was able to grow between 4 and 42°C (with an optimum temperature of 28°C) at pH values of 6-8.5 and in 0%-7% (w/v) NaCl. The dominant quinones were MK-8 and MK-7. The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, and an unknown phospholipid. The majority of the fatty acid content was anteiso-C (28.8%) followed by C ω7c alcohol (20.9%) and iso-C (13.4%). The 16S rRNA gene sequence similarity analysis demonstrated a stable branch formed by strain Y74 and Planococcus halotolerans SCU63 (99.66%). The digital DNA-DNA hybridization between these two strains was 57.2%. The G + C content in the DNA of Y74 was 44.5 mol%. In addition, the morphological, physiological, and chemotaxonomic pattern clearly differentiated the isolates from their known relatives. In conclusion, the strain Y74 (=JCM 32826 = CICC24461 ) represents a novel member of the genus Planococcus, for which the name Planococcus antioxidans sp. nov. is proposed. Strain Y74 was found to have potent antioxidant activity via its hydrogen peroxide tolerance and its 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity. The DPPH radical-scavenging activity was determined to be 40.2 ± 0.7%. The genomic analysis indicated that six peroxidases genes, one superoxide dismutase gene, and one dprA (DNA-protecting protein) are present in the genome of Y74 .
Topics: Antioxidants; Bacterial Typing Techniques; Base Composition; DNA, Bacterial; Fatty Acids; Genome, Bacterial; Planococcus Bacteria; Sequence Analysis, DNA; Soil Microbiology; Tibet; Whole Genome Sequencing
PubMed: 32162498
DOI: 10.1002/mbo3.1028 -
Microorganisms Dec 2021Marine bacterial biomineralisation by CaCO precipitation provides natural limestone structures, like beachrocks and stromatolites. Calcareous deposits can also be...
Marine bacterial biomineralisation by CaCO precipitation provides natural limestone structures, like beachrocks and stromatolites. Calcareous deposits can also be abiotically formed in seawater at the surface of steel grids under cathodic polarisation. In this work, we showed that this mineral-rich alkaline environment harbours bacteria belonging to different genera able to induce CaCO precipitation. We previously isolated 14 biocalcifying marine bacteria from electrochemically formed calcareous deposits and their immediate environment. By microscopy and µ-Raman spectroscopy, these bacterial strains were shown to produce calcite-type CaCO. Identification by 16S rDNA sequencing provided between 98.5 and 100% identity with genera and . All 14 strains produced carbonic anhydrase, and six were urease positive. Both proteins are major enzymes involved in the biocalcification process. However, this does not preclude that one or more other metabolisms could also be involved in the process. In the presence of urea, CD6 exhibited the most efficient precipitation of CaCO. However, the urease pathway has the disadvantage of producing ammonia, a toxic molecule. We showed herein that different marine bacteria could induce CaCO precipitation without urea. These bacteria could then be used for eco-friendly applications, e.g., the formation of bio-cements to strengthen dikes and delay coastal erosion.
PubMed: 35056526
DOI: 10.3390/microorganisms10010076 -
PeerJ 2024Plastic waste is a global environmental issue that impacts the well-being of humans, animals, plants, and microorganisms. Microplastic contamination has been previously...
BACKGROUND
Plastic waste is a global environmental issue that impacts the well-being of humans, animals, plants, and microorganisms. Microplastic contamination has been previously reported at Kung Wiman Beach, located in Chanthaburi province along with the Eastern Gulf of Thailand. Our research aimed to study the microbial population of the sand and plastisphere and isolate microorganisms with potential plastic degradation activity.
METHODS
Plastic and sand samples were collected from Kung Wiman Beach for microbial isolation on agar plates. The plastic samples were identified by Fourier-transform infrared spectroscopy. Plastic degradation properties were evaluated by observing the halo zone on mineral salts medium (MSM) supplemented with emulsified plastics, including polystyrene (PS), polylactic acid (PLA), polyvinyl chloride (PVC), and bis (2-hydroxyethyl) terephthalate (BHET). Bacteria and fungi were identified by analyzing nucleotide sequence analysis of the 16S rRNA and internal transcribed spacer (ITS) regions, respectively. 16S and ITS microbiomes analysis was conducted on the total DNA extracted from each sample to assess the microbial communities.
RESULTS
Of 16 plastic samples, five were identified as polypropylene (PP), four as polystyrene (PS), four as polyethylene terephthalate (PET), two as high-density polyethylene (HDPE), and one sample remained unidentified. Only 27 bacterial and 38 fungal isolates were found to have the ability to degrade PLA or BHET on MSM agar. However, none showed degradation capabilities for PS or PVC on MSM agar. Notably, sp. PP5 showed the highest hydrolysis capacity of 1.64 ± 0.12. The 16S rRNA analysis revealed 13 bacterial genera, with seven showing plastic degradation abilities: , , , , , , and . This study reports, for the first time of the BHET-degrading properties of the genera and . Additionally, The ITS analysis identified nine fungal genera, five of which demonstrated plastic degradation abilities: , , , , and . Microbial community composition analysis and linear discriminant analysis effect size revealed certain dominant microbial groups in the plastic and sand samples that were absent under culture-dependent conditions. Furthermore, 16S and ITS amplicon microbiome analysis revealed microbial groups were significantly different in the plastic and sand samples collected.
CONCLUSIONS
We reported on the microbial communities found on the plastisphere at Kung Wiman Beach and isolated and identified microbes with the capacity to degrade PLA and BHET.
Topics: Actinomycetales; Agar; Bacteria; Microbiota; Plastics; Polyesters; Polystyrenes; RNA, Ribosomal, 16S; Sand
PubMed: 38590706
DOI: 10.7717/peerj.17165 -
Waste Management (New York, N.Y.) Oct 2023The objective of this study was to investigate the potential effects of thermophilic bacterial consortia on compost efficiency and quality. The application of bacterial...
The objective of this study was to investigate the potential effects of thermophilic bacterial consortia on compost efficiency and quality. The application of bacterial consortia resulted in an earlier onset of the thermophilic period (THP), an increased upper temperature limit, and an extended duration of the THP by 3-5 days compared to the control group (CK). Microbial inoculation significantly improved the efficiency of organic matter degradation, as well as the content of water-soluble nitrogen (WSN) and humic acid-carbon (HAC). In the case of consortium Ⅱ inoculation (T2), the activities of cellobiohydrolase, β-glucosidase, and protease were increased by 81.81 %, 70.13 %, and 74.09 % at the THP respectively compared to CK. During the maturation stage, T2 also exhibited the highest P, n/P, n value (1.33) and HAC content (39.53 mg·g), indicating that inoculation of consortium Ⅱ effectively promoted substrate maturity and product quality. Moreover, this inoculation effectively optimized the bacterial communities, particularly the growth of Planococcus, Chelatococcus, and Chelativorans during the composting, which were involved in carbon and nitrogen conversion or HAC synthesis. Carbohydrate and amino acid metabolism, and membrane transport were predominant in the consortia-inoculated samples, with an increased gene abundance, suggesting that inoculation contributed to promoting the biodegradation of lignocellulose and the exchange of favorable factors. In conclusion, this study demonstrates that inoculating thermophilic bacterial consortia has a positive impact on enhancing the resource utilization efficiency of agricultural waste and improving the quality of compost products.
PubMed: 37748282
DOI: 10.1016/j.wasman.2023.09.023 -
Bioresource Technology Aug 2023This study compared the effects of alkaline, thermal, thermal-peroxymonosulfate (PMS), and alkyl polyglucose (APG) pretreatments on volatile fatty acids (VFAs)...
This study compared the effects of alkaline, thermal, thermal-peroxymonosulfate (PMS), and alkyl polyglucose (APG) pretreatments on volatile fatty acids (VFAs) production from refinery waste activated sludge (RWAS), including VFAs yield, composition, organics components, microbial communities, and the potential improvement of mechanisms. All pretreatments effectively enhanced the bioconversion of RWAS and consequently promoted the hydrolysis process, which inhibited the methanogenesis process. However, the release of lignin/carboxyl-rich alicyclic molecules (CRAM)-like compounds and tannin substances in Thermal-PMS and APG groups significantly influenced the acidogenesis and acetogenesis processes. Among all pretreatments, alkaline pretreatment showed the highest VFAs yield of 95.06 mg/g volatile solids (VS) and VS removal of 17%. This result could be associated with the enrichment of functional hydrolytic-acidification bacteria, such as Planococcus and Soehngenia, and increased metabolism of amino acids, carbohydrates, and nucleotides. By considering an economical and efficient perspective, this study recommended the alkaline pretreatment for the anaerobic fermentation of RWAS.
Topics: Fermentation; Sewage; Anaerobiosis; Fatty Acids, Volatile; Carbohydrate Metabolism; Glucans; Hydrogen-Ion Concentration
PubMed: 37141997
DOI: 10.1016/j.biortech.2023.129122 -
PeerJ 2020Numerous bacteria entered the viable but non-culturable state due to the stresses of dry and salt in soils. YeaZ of Gram-negative bacteria is a resuscitation promoting...
Numerous bacteria entered the viable but non-culturable state due to the stresses of dry and salt in soils. YeaZ of Gram-negative bacteria is a resuscitation promoting factor (Rpf) homologous protein could resuscitate bacteria of natural environment in VBNC state. To investigate the promoting effect of YeaZ on the isolation of viable but non-culturable (VBNC) bacteria from soil samples in extreme environments, the recombinant YeaZ of was prepared and added to the soil samples from volcanic soil and saline soil in Northwest China. The study has shown that YeaZ can promote the recovery and growth of soil microorganisms, and the number of cultivable bacteria in volcanic and saline soil has increased from 0.17 × 10 and 2.03 × 10 cfu⋅ml to 1.00 × 10 and 5.55 × 10 cfu⋅ml, respectively. The 16S rDNA gene sequencing and phylogenetic analysis showed that YeaZ played an essential role in the increase of composition and diversity of bacteria. A total of 13 bacterial strains were isolated from the volcanic soil samples, which belong to phyla Actinobacteria, Firmicutes and Gamma-proteobacteria. Four species, including , , and were found in the control group, while , , , , and were isolated from the treatment groups (addition of YeaZ). Twenty-one strains were isolated from the saline soil samples, including eight species from the control group and thirteen species from the treatment groups, among which nine species were only found, including , , , , , , , and . The results suggest that addition of YeaZ to soil samples can promote the recovery of VBNC. This method has the implications for the discovery of VBNC bacteria that have potential environmental functions.
PubMed: 33391864
DOI: 10.7717/peerj.10342 -
Scientific Reports Mar 2021Dwarf bunt of wheat, which is caused by Tilletia controversa J.G. Kühn, is a soil-borne disease which may lead up to an 80% loss of yield together with degradation of...
Dwarf bunt of wheat, which is caused by Tilletia controversa J.G. Kühn, is a soil-borne disease which may lead up to an 80% loss of yield together with degradation of the quality of the wheat flour by production of a fishy smell. In this study, high-throughput sequencing technology was employed to characterize the microbial composition of wheat tissues (roots, spikes, first stem under the ear, and stem base) and rhizosphere soil of wheat varieties that are resistant and susceptible to T. controversa. We observed that the soil fungal community abundance and diversity were higher in resistant varieties than in susceptible varieties in both inoculated and uninoculated wheat, and the abundances of Sordariomycetes and Mortierellomycetes increased in the resistant varieties infected with T. controversa, while the abundances of Dothideomycetes and Bacteroidia increased in the susceptible varieties. Regarding the bacteria present in wheat tissues, the abundances of Chloroflexi, Bacteroidetes, Gemmatimonadetes, Verrucomicrobia and Acidobacteria in the ear and the first stem under the ear were higher than those in other tissues. Our results indicated that the abundances of Sordariomycetes, Mortierellomycetes, Leotiomycetes, Chryseobacterium and Massilia were higher in T. controversa-infected resistant varieties than in their controls, that Dothideomycetes, Bacteroidia, Nocardioides and Pseudomonas showed higher abundances in T. controversa-infected susceptible varieties, and that Curtobacterium, Exiguobacterium, Planococcus, and Pantoea may have higher abundances in both T. controversa-infected susceptible and resistant varieties than in their own controls.
Topics: Bacteria; Biodiversity; Endophytes; Fungi; Microbiota; Plant Diseases; Plant Leaves; Plant Roots; Plant Stems; Principal Component Analysis; Rhizosphere; Sequence Analysis, DNA; Soil Microbiology; Triticum
PubMed: 33707584
DOI: 10.1038/s41598-021-85281-8 -
Applied Biochemistry and Biotechnology Feb 2020Microorganisms that survive in the high salt environment have been shown to be a potential source for metabolites with pharmaceutical importance. In the present study,...
Microorganisms that survive in the high salt environment have been shown to be a potential source for metabolites with pharmaceutical importance. In the present study, we have investigated the effect of 5 and 10% (w/v) NaCl on growth, biochemical changes, and metabolite production in seven moderately halophilic bacteria isolated from the salterns/mangrove area of South India. Metabolite production by Bacillus VITPS3 increased by 3.18-fold in the presence of 10% (w/v) NaCl concentration. Total phenolic and flavonoid content increased in Bacillus VITPS5 (11.3-fold) and Planococcus maritimus VITP21 (5.99-fold) whereas β-carotene content was less at higher NaCl concentrations. VITP21 and VITPS5, in response to NaCl, produced metabolites with higher (6.72- and 4.91-fold) DPPH and ABTS radical scavenging activity. UV/visible spectrophotometry of the extracts confirmed the presence of flavonoids, phenolics, and related compounds. H-NMR spectra indicated substantial changes in the metabolite production in response to salt concentration. Principal component analysis (PCA) revealed that VITP21 extracts exhibited the highest antioxidant activity compared with other extracts. The present study presents the first report on the comparative analysis of pigment production by moderate halophilic bacteria, in response to the effect of salt and their relation to radical scavenging property.
Topics: Antioxidants; Bacillus; Biphenyl Compounds; Free Radical Scavengers; Picrates; Pigments, Biological; Planococcus Bacteria; Sodium Chloride
PubMed: 31363982
DOI: 10.1007/s12010-019-03107-w -
International Journal of Environmental... Apr 2022Taking into consideration the essential contribution of farming, it is of rising importance to add knowledge regarding bacterial species occurrence in water samples...
Taking into consideration the essential contribution of farming, it is of rising importance to add knowledge regarding bacterial species occurrence in water samples from aquaculture zones from the point of view of both the organism and public health. In the present study, we investigated the bacterial community existing in water samples from six aquaculture areas in the Thermaikos gulf, northern Greece, that may provoke toxicity in aquatic organisms and humans and may indicate environmental pollution in mussel production as well as algal blooms. Bacterial species were identified molecularly by sequencing of a partial 16s rRNA segment and were analyzed phylogenetically for the confirmation of the bacterial taxonomy. The results obtained revealed the presence of four bacterial genera ( sp., sp., sp., and sp.). Members of the and genera have been isolated from highly polluted sites, bacteria have been identified in samples derived directly from plastic debris, and bacteria are in line with microcystin detection. In this context, the monitoring of the bacteria community in mussel aquaculture water samples from the Thermaikos gulf, the largest mussel cultivation area in Greece, represents an indicator of water pollution, microplastics presence, algal blooms, and toxin presence.
Topics: Animals; Cyanobacteria; Greece; Humans; Mytilus; Plastics; RNA, Ribosomal, 16S; Water; Water Pollution
PubMed: 35564680
DOI: 10.3390/ijerph19095285