-
Microorganisms May 2023The accumulation of xenobiotic compounds in different environments interrupts the natural ecosystem and induces high toxicity in non-target organisms. Diclofenac is one...
The accumulation of xenobiotic compounds in different environments interrupts the natural ecosystem and induces high toxicity in non-target organisms. Diclofenac is one of the commonly used pharmaceutical drugs that persist in the environment due to its low natural degradation rate and high toxicity. Therefore, this study aimed to isolate potential diclofenac-degrading bacteria, detect the intermediate metabolites formed, and determine the enzyme involved in the degradation process. Four bacterial isolates were selected based on their ability to utilize a high concentration of diclofenac (40 mg/L) as the sole carbon source. The growth conditions for diclofenac degradation were optimized, and bacteria were identified as (S1), (S2), (S11), and (S18). The highest percentage of degradation was recorded (97.79 ± 0.84) after six days of incubation for S11, as analyzed by HPLC. To detect and identify biodegradation metabolites, the GC-MS technique was conducted for the most efficient bacterial strains. In all tested isolates, the initial hydroxylation of diclofenac was detected. The cleavage step of the NH bridge between the aromatic rings and the subsequent cleavage of the ring adjacent to or in between the two hydroxyl groups of polyhydroxylated derivatives might be a key step that enables the complete biodegradation of diclofenac by S18, as well as S1. Additionally, the laccase, peroxidase, and dioxygenase enzyme activities of the two strains, as well as S1, were tested in the presence and absence of diclofenac. The obtained results from this work are expected to be a useful reference for the development of effective detoxification bioprocesses utilizing bacterial cells as biocatalysts. The complete removal of pharmaceuticals from polluted water will stimulate water reuse, meeting the growing worldwide demand for clean and safe freshwater.
PubMed: 37374947
DOI: 10.3390/microorganisms11061445 -
Journal of Basic Microbiology Feb 2022Microbial enzymatic degradation of biowaste is a sustainable and environmentally friendly solution for eliminating biowaste pollution. It is the underlying cause of the...
Microbial enzymatic degradation of biowaste is a sustainable and environmentally friendly solution for eliminating biowaste pollution. It is the underlying cause of the ever-increasing demand for harnessing multipurpose microbes to work as an entity under given complex processes. Twelve bacterial strains of bovine manure were evaluated for their hydrolytic enzyme activity and optimization. Six enzymes; cellulase, amylase, pectinase, chitinase, protease, and gelatinase were selected based on their corresponding abundant biowaste, that is, cellulose, proteinaceous, chitin, and polymeric starchy biowaste. The preliminary qualitative screening was followed by quantitative enzyme production as well as optimal enzyme production conditions. Irrespective of their sample source and origin, all strains showed the highest enzyme production when grown at 40°C for 72 h with pH 7. Comparatively, among the selected enzymes, strains were higher producers of cellulase, protease, and gelatinase. The present study reported the first time Brevibacillus parabrevis (DZ.15) as pectinase producer, Achromobacter spanius (DZ.1) as amylase-protease-chitinase producer, Achromobacter piechaudii (DZ.12) as pectinase-chitinase-gelatinase producer, and two Achromobacter kerstersii (DZ.16 and DZ.17) as pectinase-chitinase producers. Therefore, this study suggested that bovine manure microbes exhibiting novel potential can be used for hydrolysis of environmental biowaste.
Topics: Animals; Cattle; Chitin; Chitinases; Hydrolysis; Manure; Peptide Hydrolases
PubMed: 35103341
DOI: 10.1002/jobm.202100294 -
Scientific Reports Feb 2021Phoma stem canker (caused by the ascomycetes Leptosphaeria maculans and Leptosphaeria biglobosa) is an important disease of oilseed rape. Its effect on endophyte...
Phoma stem canker (caused by the ascomycetes Leptosphaeria maculans and Leptosphaeria biglobosa) is an important disease of oilseed rape. Its effect on endophyte communities in roots and shoots and the potential of endophytes to promote growth and control diseases of oilseed rape (OSR) was investigated. Phoma stem canker had a large effect especially on fungal but also on bacterial endophyte communities. Dominant bacterial genera were Pseudomonas, followed by Enterobacter, Serratia, Stenotrophomonas, Bacillus and Staphylococcus. Achromobacter, Pectobacter and Sphingobacterium were isolated only from diseased plants, though in very small numbers. The fungal genera Cladosporium, Botrytis and Torula were dominant in healthy plants whereas Alternaria, Fusarium and Basidiomycetes (Vishniacozyma, Holtermaniella, Bjerkandera/Thanatephorus) occurred exclusively in diseased plants. Remarkably, Leptosphaeria biglobosa could be isolated in large numbers from shoots of both healthy and diseased plants. Plant growth promoting properties (antioxidative activity, P-solubilisation, production of phytohormones and siderophores) were widespread in OSR endophytes. Although none of the tested bacterial endophytes (Achromobacter, Enterobacter, Pseudomonas, Serratia and Stenotrophomonas) promoted growth of oilseed rape under P-limiting conditions or controlled Phoma disease on oilseed rape cotyledons, they significantly reduced incidence of Sclerotinia disease. In the field, a combined inoculum consisting of Achromobacter piechaudii, two pseudomonads and Stenotrophomonas rhizophila tendencially increased OSR yield and reduced Phoma stem canker.
Topics: Achromobacter; Ascomycota; Brassica napus; Disease Resistance; Endophytes; Mycobiome; Phoma; Plant Diseases; Plant Roots; Stenotrophomonas
PubMed: 33589671
DOI: 10.1038/s41598-021-81937-7 -
New Biotechnology Mar 2017Thermo-solar plants use eutectic mixtures of diphenyl ether (DE) and biphenyl (BP) as heat transfer fluid (HTF). Potential losses of HTF may contaminate soils and...
Thermo-solar plants use eutectic mixtures of diphenyl ether (DE) and biphenyl (BP) as heat transfer fluid (HTF). Potential losses of HTF may contaminate soils and bioremediation is an attractive tool for its treatment. DE- or BP-degrading bacteria are known, but up to now bacteria able to degrade HTF mixture have not been described. Here, five bacterial strains which are able to grow with HTF or its separate components DE and BP as sole carbon sources have been isolated, either from soils exposed to HTF or from rhizospheric soils of plants growing near a thermo-solar plant. The organisms were identified by 16S rRNA gene sequencing as Achromobacter piechaudii strain BioC1, Pseudomonas plecoglossicida strain 6.1, Pseudomonas aeruginosa strains HBD1 and HBD3, and Pseudomonas oleovorans strain HBD2. Activity of 2,3-dihydroxybiphenyl dioxygenase (BphC), a key enzyme of the biphenyl upper degradation pathway, was detected in all isolates. Pseudomonas strains almost completely degraded 2000ppm HTF after 5-day culture, and even tolerated and grew in the presence of 150,000ppm HTF, being suitable candidates for in situ soil bioremediation. Degradation of both components of HTF is of particular interest since in the DE-degrader Sphingomonas sp. SS3, growth on DE or benzoate was strongly inhibited by addition of BP.
Topics: Achromobacter; Biodegradation, Environmental; Biotechnology; Biphenyl Compounds; Hot Temperature; Industrial Microbiology; Phenyl Ethers; Pseudomonas; Pseudomonas aeruginosa; Pseudomonas oleovorans; Rhizosphere; Soil Microbiology; Solar Energy
PubMed: 27884748
DOI: 10.1016/j.nbt.2016.11.003 -
Frontiers in Plant Science 2016Application of hyperaccumulator-endophyte symbiotic systems is a potential approach to improve phytoremediation efficiency, since some beneficial endophytic bacteria are...
Application of hyperaccumulator-endophyte symbiotic systems is a potential approach to improve phytoremediation efficiency, since some beneficial endophytic bacteria are able to detoxify heavy metals, alter metal solubility in soil, and facilitate plant growth. The objective of this study was to isolate multi-metal resistant and plant beneficial endophytic bacteria and to evaluate their role in enhancing plant growth and metal accumulation/translocation. The metal resistant endophytic bacterial strain E6S was isolated from stems of the Zn/Cd hyperaccumulator plant Sedum plumbizincicola growing in metalliferous mine soils using Dworkin and Foster salts minimal agar medium with 1-aminocyclopropane-1-carboxylate (ACC) as the sole nitrogen source, and identified as homologous to Achromobacter piechaudii based on morphological and biochemical characteristics, partial 16S rDNA sequence and phylogenetic analysis. Strain E6S showed high level of resistance to various metals (Cd, Zn, and Pb). Besides utilizing ACC, strain E6S exhibited plant beneficial traits, such as solubilization of phosphate and production of indole-3-acetic acid. Inoculation with E6S significantly increased the bioavailability of Cd, Zn, and Pb in soil. In addition, bacterial cells bound considerable amounts of metal ions in the following order: Zn > Cd >Pb. Inoculation of E6S significantly stimulated plant biomass, uptake and bioaccumulation of Cd, Zn, and Pb. However, E6S greatly reduced the root to shoot translocation of Cd and Zn, indicating that bacterial inoculation assisted the host plant to uptake and store heavy metals in its root system. Inoculation with the endophytic bacterium E6S homologous to A. piechaudii can improve phytostabilization of metalliferous soils due to its effective ability to enhance in situ metal rhizoaccumulation in plants.
PubMed: 26870079
DOI: 10.3389/fpls.2016.00075 -
Genome Announcements Jan 2016A variety of bacteria associate with the hydrocarbon-producing microalga Botryococcus braunii, some of which may influence its growth. We report here the genome...
Draft Genome Sequences of Achromobacter piechaudii GCS2, Agrobacterium sp. Strain SUL3, Microbacterium sp. Strain GCS4, Shinella sp. Strain GWS1, and Shinella sp. Strain SUS2 Isolated from Consortium with the Hydrocarbon-Producing Alga Botryococcus braunii.
A variety of bacteria associate with the hydrocarbon-producing microalga Botryococcus braunii, some of which may influence its growth. We report here the genome sequences for Achromobacter piechaudii GCS2, Agrobacterium sp. strain SUL3, Microbacterium sp. strain GCS4, and Shinella sp. strains GWS1 and SUS2, isolated from a laboratory culture of B. braunii, race B, strain Guadeloupe.
PubMed: 26769927
DOI: 10.1128/genomeA.01527-15