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Microbial Ecology Jun 2024Plastic pollution poses a worldwide environmental challenge, affecting wildlife and human health. Assessing the biodegradation capabilities of natural microbiomes in...
Plastic pollution poses a worldwide environmental challenge, affecting wildlife and human health. Assessing the biodegradation capabilities of natural microbiomes in environments contaminated with microplastics is crucial for mitigating the effects of plastic pollution. In this work, we evaluated the potential of landfill leachate (LL) and estuarine sediments (ES) to biodegrade polyethylene (PE), polyethylene terephthalate (PET), and polycaprolactone (PCL), under aerobic, anaerobic, thermophilic, and mesophilic conditions. PCL underwent extensive aerobic biodegradation with LL (99 ± 7%) and ES (78 ± 3%) within 50-60 days. Under anaerobic conditions, LL degraded 87 ± 19% of PCL in 60 days, whereas ES showed minimal biodegradation (3 ± 0.3%). PE and PET showed no notable degradation. Metataxonomics results (16S rRNA sequencing) revealed the presence of highly abundant thermophilic microorganisms assigned to Coprothermobacter sp. (6.8% and 28% relative abundance in anaerobic and aerobic incubations, respectively). Coprothermobacter spp. contain genes encoding two enzymes, an esterase and a thermostable monoacylglycerol lipase, that can potentially catalyze PCL hydrolysis. These results suggest that Coprothermobacter sp. may be pivotal in landfill leachate microbiomes for thermophilic PCL biodegradation across varying conditions. The anaerobic microbial community was dominated by hydrogenotrophic methanogens assigned to Methanothermobacter sp. (21%), pointing at possible syntrophic interactions with Coprothermobacter sp. (a H-producer) during PCL biodegradation. In the aerobic experiments, fungi dominated the eukaryotic microbial community (e.g., Exophiala (41%), Penicillium (17%), and Mucor (18%)), suggesting that aerobic PCL biodegradation by LL involves collaboration between fungi and bacteria. Our findings bring insights on the microbial communities and microbial interactions mediating plastic biodegradation, offering valuable perspectives for plastic pollution mitigation.
Topics: Biodegradation, Environmental; Microbiota; Microplastics; Waste Disposal Facilities; Bacteria; Water Pollutants, Chemical; Polyesters; Geologic Sediments; RNA, Ribosomal, 16S; Estuaries; Polyethylene; Polyethylene Terephthalates
PubMed: 38943017
DOI: 10.1007/s00248-024-02399-8 -
Scientific Reports Jun 2024Improved and contemporary agriculture relies heavily on pesticides, yet some can be quite persistent and have a stable chemical composition, posing a significant threat...
Improved and contemporary agriculture relies heavily on pesticides, yet some can be quite persistent and have a stable chemical composition, posing a significant threat to the ecology. Removing harmful effects is upon their degradability. Biodegradation must be emphasized to lower pesticide degradation costs, especially in the soil. Here, a decision-making system was used to determine the best microbial strain for the biodegradation of the pyrethroid-contaminated soil. In this system, the criteria chosen as: pH (C), Temp (C), RPM (C), Conc. (C), Degradation (%) (C) and Time required for degradation(hrs) (C); and five alternatives were Bacillus (A), Acinetobacter (A), Escherichia (A), Pseudomonas (A), and Fusarium (A). The best alternative was selected by applying the TOPSIS (technique for order performance by similarity to ideal solution) method, which evaluates based on their closeness to the ideal solution and how well they meet specific requirements. Among all the specified criteria, Acinetobacter (A) was the best and optimal based on the relative closeness value (( ) = 0.740 (A) > 0.544 (A) > 0.480 (A) > 0.403 (A) > 0.296 (A)). However, the ranking of the other alternatives is also obtained in the order Fusarium (A), Bacillus (A), Pseudomonas (A), Escherichia (A). Hence this study suggests Acinetobacter is the best microbial strain for biodegradation of pyrethroids; while least preference should be given to Escherichia. Acinetobacter, versatile metabolic nature with various xenobiotic compounds' degradation ability, is gram-negative, aerobic, coccobacilli, nonmotile, and nonspore forming bacteria. Due to less study about Acinetobacter it is not in that much frame as the other microorganisms. Hence, considering the Acinetobacter strain for the biodegradation study will give more optimal results than the other microbial strains. Novelty of this study, the TOPSIS method is applied first time in selecting the best microbial strain for the biodegradation of pyrethroid-contaminated soil, considering this selection process as multi-criteria decision-making (MCDM) problem.
Topics: Biodegradation, Environmental; Pyrethrins; Soil Pollutants; Soil Microbiology; Bacteria; Bacillus; Fusarium; Decision Making; Pseudomonas; Acinetobacter
PubMed: 38942772
DOI: 10.1038/s41598-024-59223-z -
Functional analysis of transmembrane terpene cyclases involved in fungal meroterpenoid biosynthesis.Methods in Enzymology 2024Pyr4-family terpene cyclases are noncanonical transmembrane class II terpene cyclases that catalyze a variety of cyclization reactions in the biosynthesis of microbial...
Pyr4-family terpene cyclases are noncanonical transmembrane class II terpene cyclases that catalyze a variety of cyclization reactions in the biosynthesis of microbial terpenoids, such as meroterpenoids. However, although these cyclases are widely distributed in microorganisms, their three-dimensional structures have not been determined, possibly due to the transmembrane locations of these enzymes. In this chapter, we describe procedures for the functional analysis of transmembrane terpene cyclases based on their model structures generated using AlphaFold2. We used AdrI, the Pyr4-family terpene cyclase required for the biosynthesis of andrastin A and its homologs, as an example.
Topics: Terpenes; Fungal Proteins; Cyclization; Models, Molecular; Fungi; Alkyl and Aryl Transferases
PubMed: 38942513
DOI: 10.1016/bs.mie.2024.02.007 -
PDA Journal of Pharmaceutical Science... Jun 2024Microbiological contamination may cause microbial proliferation and consequently additional problems for pharmaceutical companies through production stoppage, product...
Quantitative and qualitative evaluation of microorganism profile identified in bioburden analysis in a biopharmaceutical facility in Brazil: Criteria for classification and management of results.
Microbiological contamination may cause microbial proliferation and consequently additional problems for pharmaceutical companies through production stoppage, product contamination, investigations of process deviations, out-of-specification results and product disposal. This is one of the major concerns of the regulatory health agencies. Microbiological load (bioburden) may represent a potential risk for patients if the sterilization process is not effective and/or due to the production of toxins. Although bioburden can be eliminated by terminal sterilization or filtration processes, it is important to monitor the amount and determine the identity and characteristics of the microorganisms present prior to final processing. The application of microorganism identification systems is crucial for identifying the type of contamination, which can be extremely useful for investigating. The aim of this study was to evaluate the profiles of microorganisms identified in bioburden assays from solutions, culture medias, and products (SCP) from a pharmaceutical industry facility. From 2018-2020, a total of 1,078 samples from 857 different lots of SCP were analyzed and isolated microorganisms were identified. A prefiltering step was included after March 2020, in order to reduce the bioburden before sterilizing filtration. Criteria for the definition and management of microorganisms identified were evaluated after an integrative bibliographic review, and three groups were proposed (critical, objectionable, and nonobjectionable microorganisms). For the samples that did not include prefiltering (n=636), 227 (35.7%) presented microbial growth. For those that included prefiltering, before prefiltering (n=221), 60.6% presented microbial growth, and after prefiltering, this value was reduced to 4.1%, which can be attributed to a contamination during the sampling or a wrong filtering. From the samples that presented microbial growth, 678 microorganisms were identified as bacteria and 59 as molds and yeasts. A total of 120 microorganisms (56 and 27 Gram-positive and negative bacteria, respectively, 31 yeasts, and six filamentous molds) could not be identified, and the remaining microorganisms were classified as objectionable (n=507; 82.2%), nonobjectionable (n=103; 16.7%) and critical (n=7; 1.1%). Most of the bioburden species (>80.0%) were considered objectionable microorganisms. A process for classification and management of bioburden analysis results based on a literature review of pathogenic and physiological characteristics of the microorganisms was proposed.
PubMed: 38942484
DOI: 10.5731/pdajpst.2023.012883 -
PDA Journal of Pharmaceutical Science... Jun 2024In the execution of its legislated responsibilities, the United States Food and Drug Administration commonly refers to standard test methods detailed in the United... (Review)
Review
In the execution of its legislated responsibilities, the United States Food and Drug Administration commonly refers to standard test methods detailed in the United States Pharmacopeia (USP). Microbiological test methods (contained in general chapters) are listed in chapters <51> to <80> with details regarded as enforceable where referenced as a test method. USP <61> "Microbiological Examination of Nonsterile Products: Microbial Enumeration Tests" is a globally harmonized chapter that has been successfully employed for the enumeration of microorganisms recoverable from nonsterile finished drug products. The content of USP <61> is not always scientifically principled nor emphatically understood by all pharmaceutical microbiologists. Consequently, misunderstanding and misapplication of USP <61> may result in analyses and assessments of microbiological quality that are flawed or erroneous. In this article, clarification is provided to assist the pharmaceutical microbiologist in the appropriate and intended use of USP <61>, including provision of details not always commonly known or understood.
Topics: Pharmacopoeias as Topic; Drug Contamination; United States; United States Food and Drug Administration; Microbiological Techniques; Colony Count, Microbial; Pharmaceutical Preparations
PubMed: 38942475
DOI: 10.5731/pdajpst.2023.012855 -
International Journal of Biological... Jun 2024The highly efficient removal of oils such as oils or dyes from wastewater has aroused wide concern and is of great significance for clean production and environmental...
The highly efficient removal of oils such as oils or dyes from wastewater has aroused wide concern and is of great significance for clean production and environmental remediation. The synthesis of a novel aerogel (designated as HEC/LS) is reported herein, achieved through a sol-gel method followed by freeze-drying utilizing loofa and hydroxyethyl cellulose as the raw materials. The new HEC/LS aerogel exhibits excellent porosity and specific surface area, with a porosity of 88.70 %, a total pore area of 0.607 m g, and a specific surface area of 230 m g. The prepared HEC/LS aerogel exhibits exceptional hydrophilicity and self-floatability, facilitating its rapid absorption of water up to 21 times its own weight within a mere 3 s. Additionally, it demonstrates good adsorption performance for methylene blue (MB), with a maximum adsorption capacity of 83.30 mg g. Subsequently, a new hydrophobic microorganisms-loaded composite aerogel (namely, Bn-HEC/LS) was obtained by doping microorganisms into the as-prepared HEC/LS in multiple enrichment followed by a hydrophobic and oleophilic surface modification. Based on its rich porous structure and oleophilic wettability, the as-synthesized Bn-HEC/LS exhibits excellent selective adsorption and degradation properties for the oil contamination, the diesel oil could be selectively absorbed in the Bn-HEC/LS and degraded by the loaded microorganisms. Among them, B-HEC/LS displays the highest removal efficiency of 94.50 % within 180 h, while free microorganisms and HEC/LS aerogels show degradation efficiencies of only 21.70 % and 48.10 %, respectively. The fixation of microorganisms in the aerogel increases their number within the material and enhances the relative microorganisms removal capacity. The hydrophobic and lipophilic modifications improve the selective adsorption performance of the aerogel on diesel oil, resulting in a significantly high removal rate of Bn-HEC/LS for diesel oil. The results indicate that the immobilization of microorganisms into aerogel improves the activity of microorganisms, and the hydrophobic and oleophilic modification enhances the selective adsorption performance of aerogel to diesel oil, thus resulting in a very high removal rate of Bn-HEC/LS for diesel oil. This study is expected to provide a now possibility for the green and efficient bioremediation of oils.
PubMed: 38942413
DOI: 10.1016/j.ijbiomac.2024.133477 -
The Science of the Total Environment Jun 2024Since the 1980s, there has been increasing concern over heavy metal pollution remediation. However, most research focused on the individual remediation technologies for... (Review)
Review
Since the 1980s, there has been increasing concern over heavy metal pollution remediation. However, most research focused on the individual remediation technologies for heavy metal pollutants in either soil or water. Considering the potential migration of these pollutants, it is necessary to explore effective integrated remediation technologies for soil and water heavy metals. This review thoroughly examines non-phytoremediation technologies likes physical, chemical, and microbial remediation, as well as green remediation approaches involving terrestrial and aquatic phytoremediation. Non-phytoremediation technologies suffer from disadvantages like high costs, secondary pollution risks, and susceptibility to environmental factors. Conversely, phytoremediation technologies have gained significant attention due to their sustainable and environmentally friendly nature. Enhancements through chelating agents, biochar, microorganisms, and genetic engineering have demonstrated improved phytoremediation remediation efficiency. However, it is essential to address the environmental and ecological risks that may arise from the prolonged utilization of these materials and technologies. Lastly, this paper presents an overview of integrated remediation approaches for addressing heavy metal contamination in groundwater-soil-surface water systems and discusses the reasons for the research gaps and future directions. This paper offers valuable insights for comprehensive solutions to heavy metal pollution in water and soil, promoting integrated remediation and sustainable development.
PubMed: 38942300
DOI: 10.1016/j.scitotenv.2024.174237 -
Environmental Research Jun 2024Dye wastewater consists of high solids concentrations, heavy metals, minor contaminants, dissolved chemical oxygen demand, and microorganisms. Nanoflowers are... (Review)
Review
Dye wastewater consists of high solids concentrations, heavy metals, minor contaminants, dissolved chemical oxygen demand, and microorganisms. Nanoflowers are nanoparticles that resemble flowers when viewed at a microscopic level. Inorganic metal oxide nanoflowers have been discovered to be a potential source for overcoming this situation. Their flower-like features give them a higher surface area to volume ratio and porosity structure, which can absorb a significant amount of dye. The metal oxide nanoflower synthesized from different synthesis methods is used to compare which one is cost-effective and capable of generating a large scale of nanoflower. This review has demonstrated outstanding dye removal efficiency by applying inorganic nanoflowers to dye removal. Since both adsorption and photocatalytic reactions enhance the dye degradation process, complete dye degradation could be achieved. Meanwhile, the inorganic metal oxide nanoflowers' exemplary reusability characteristics with negligible performance drop further prove that this approach is highly sustainable and may help to save costs. This review has proven the momentum of obtaining high dye removal efficiency in wastewater treatment to conclude that the metal oxide nanoflower study is worth researching.
PubMed: 38942255
DOI: 10.1016/j.envres.2024.119448 -
Fish & Shellfish Immunology Jun 2024Takifugu rubripes is a highly valued cultured fish in Asia, while pathogen infections can result in severe diseases and lead to substantial economic losses. Toll-like...
Takifugu rubripes is a highly valued cultured fish in Asia, while pathogen infections can result in severe diseases and lead to substantial economic losses. Toll-like receptors (TLRs), as pattern recognition receptors, play a crucial role on recognition pathogens and initiation innate immune response. However, the immunological properties of teleost-specific TLR23 remain largely unknown. In this study, we investigated the biological functions of TLR23 (TrTLR23) from T. rubripes, found that TrTLR23 existed in various organs. Following bacterial pathogen challenge, the expression levels of TrTLR23 were significantly increased in immune related organs. TrTLR23 located on the cellular membrane and specifically recognized pathogenic microorganism. Co-immunoprecipitation and antibody blocking analysis revealed that TrTLR23 recruited myeloid differentiation primary response protein (MyD88), thereby mediating the activation of the ERK signaling pathway. Furthermore, in vivo showed that, when TrTLR23 is overexpressed in T. rubripes, bacterial replication in fish tissues is significantly inhibited. Consistently, when TrTLR23 expression in T. rubripes is knocked down, bacterial replication is significantly enhanced. In conclusion, these findings suggested that TrTLR23 played a critical role on mediation TLR23-MyD88-ERK axis against bacterial infection. This study revealed that TLR23 involved in the innate immune mechanism, and provided the foundation for development disease control strategies in teleost.
PubMed: 38942251
DOI: 10.1016/j.fsi.2024.109724 -
Bioresource Technology Jun 2024Increasing evidence shows that microbial synthesis plays an important role in producing high value-added products. However, microbial monoculture generally hampers... (Review)
Review
Increasing evidence shows that microbial synthesis plays an important role in producing high value-added products. However, microbial monoculture generally hampers metabolites production and limits scalability due to the increased metabolic burden on the host strain. In contrast, co-culture is a more flexible approach to improve the environmental adaptability and reduce the overall metabolic burden. The well-defined co-culturing microbial consortia can tap their metabolic potential to obtain yet-to-be discovered and pre-existing metabolites. This review focuses on the use of a co-culture strategy and its underlying mechanisms to enhance the production of products. Notably, the significance of comprehending the microbial interactions, diverse communication modes, genetic information, and modular co-culture involved in co-culture systems were highlighted. Furthermore, it addresses the current challenges and outlines potential future directions for microbial co-culture. This review provides better understanding the diversity and complexity of the interesting interaction and communication to advance the development of co-culture techniques.
PubMed: 38942211
DOI: 10.1016/j.biortech.2024.131049