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Journal of Environmental Management May 2024Aquaculture pond sediments have a notable influence on the ecosystem balance and farmed animal health. In this study, microalgal-bacterial immobilization (MBI) was...
Performance enhancement, bacterial communities optimization and emerging pollutants elimination by microalgal-bacterial consortium for treating aquaculture pond sediments.
Aquaculture pond sediments have a notable influence on the ecosystem balance and farmed animal health. In this study, microalgal-bacterial immobilization (MBI) was designed to improve aquaculture pond sediments via synergistic interactions. The physicochemical characteristics, bacterial communities, and the removal efficiencies of emerging pollutants were systematically investigated. The consortium containing diatom Navicula seminulum and Alcaligenes faecalis was cultivated and established in the free and immobilized forms for evaluating the treatment performance. The results indicated that the immobilized group exhibited superior performance in controlling nutrient pollutants, shaping and optimizing the bacterial community compositions with the enrichment of functional bacteria. Additionally, it showed a stronger positive correlation between the bacterial community shifts and nutrient pollutants removal compared to free cells. Furthermore, the immobilized system maintained the higher removal performance of emerging pollutants (heavy metals, antibiotics, and pathogenic Vibrios) than free group. These findings confirmed that the employment of immobilized N. seminulum and A. faecalis produced more synergistic benefits and exerted more improvements than free cells in ameliorating aquaculture pond sediments, suggesting the potential for engineering application of functional microalgal-bacterial consortium in aquaculture.
Topics: Aquaculture; Microalgae; Ponds; Geologic Sediments; Metals, Heavy; Water Pollutants, Chemical; Bacteria; Animals
PubMed: 38723495
DOI: 10.1016/j.jenvman.2024.121013 -
Data in Brief Jun 2024The sea cucumber () is a species found in the shallow waters near coral reefs and seagrass beds in Puerto Rico. To characterize the microbial taxonomic composition and...
The sea cucumber () is a species found in the shallow waters near coral reefs and seagrass beds in Puerto Rico. To characterize the microbial taxonomic composition and functional profiles present in the sea cucumber, total DNA was obtained from their intestinal system, fosmid libraries constructed, and subsequent sequencing was performed. The diversity profile displayed that the most predominant domain was Bacteria (76.56 %), followed by Viruses (23.24 %) and Archaea (0.04 %). Within the 11 phyla identified, the most abundant was Proteobacteria (73.16 %), followed by Terrabacteria group (3.20 %) and Fibrobacterota, Chlorobiota, Bacteroidota (FCB) superphylum (1.02 %). The most abundant species were (21.77 %), (14.78 %), and (5.00 %). The functional profile revealed that the most abundant functions are related to transporters, MISC (miscellaneous information systems), organic nitrogen, energy, and carbon utilization. The data collected in this project on the diversity and functional profiles of the intestinal system of the provided a detailed view of its microbial ecology. These findings may motivate comparative studies aimed at understanding the role of the microbiome in intestinal regeneration.
PubMed: 38690316
DOI: 10.1016/j.dib.2024.110421 -
Journal of Environmental Science and... 2024Heavy metals (HMs) are widely used in various industries. High concentrations of HMs can be severely toxic to plants, animals and humans. Microorganism-based...
Heavy metals (HMs) are widely used in various industries. High concentrations of HMs can be severely toxic to plants, animals and humans. Microorganism-based bioremediation has shown significant potential in degrading and detoxifying specific HM contaminants. In this study, we cultivated a range of bacterial strains in liquid and solid nutrient medium containing different concentrations of different HMs to select and analyze bacteria capable of transforming HMs. The bacterial strains most resistant to selected HMs and exhibiting the ability to remove HMs from contaminated soils were identified. Then, the bacterial species capable of utilizing HMs in soil model experiments were selected, and their ability to transform HMs was evaluated. This study has also generated preliminary findings on the use of plants for further removal of HMs from soil after microbial bioremediation. were selected for their ability to grow in and utilize HM ions at the maximum permissible concentration (MPC) and two times the MPC. (local microflora) can be used as a universal biotransformation tool for many HM ions. has potential for the removal of lead ions, and and have potential for the removal of arsenic ions from the environment. The bacterial species have been selected for bioremediation to remove heavy metal ions from the environment.
Topics: Soil Pollutants; Metals, Heavy; Biodegradation, Environmental; Soil Microbiology; Biotransformation; Bacteria; Stenotrophomonas; Delftia; Alcaligenes faecalis
PubMed: 38676363
DOI: 10.1080/03601234.2024.2343236 -
Probiotics and Antimicrobial Proteins Apr 2024Curdlan, a β-1,3/1,6-glucan found in Alcaligenes faecalis (A. faecalis) wall, activates innate and humoral immunity. The aim of this study is to evaluate whether...
Curdlan, a β-1,3/1,6-glucan found in Alcaligenes faecalis (A. faecalis) wall, activates innate and humoral immunity. The aim of this study is to evaluate whether pretreated rats with A. faecalis A12C could prevent sepsis disturbances and identify the immunomodulatory mechanisms involved. Experiments occurred in two stages: a survival study with 16 rats randomly divided into septic (SC) (n = 8) and septic pretreated (SA) (n = 8) groups and 45 rats divided into four groups: healthy (AGUSAN) (n = 9), septic (AGUIC) (n = 13), septic pretreated (AGUIA) (n = 14), and healthy pretreated (AGUSTO) (n = 9). Sepsis was induced by cecal ligation and puncture after 30 days of A. faecalis A12C pretreatment or without. SA group had a higher survival rate of 58% vs. 16% for SC group (P < 0.05). Overall, AGUIA showed better status than AGUIC (P < 0.01). Higher monocytosis was found in AGUIA and AGUSTO vs. AGUIC and AGUSAN, respectively (P < 0.05). A gradual increase in curdlan fecal concentration was observed in AGUIA during pretreatment. Fecal concentrations of Escherichia coli significantly decreased in AGUIA and AGUSTO. Bacterial load in urine, peritoneal lavage fluid (PLF), and bronchoalveolar lavage fluid (BALF) decreased (P < 0.05) in AGUIA vs. AGUIC. Finally, lower inflammation was observed in serum, BALF, and PLF, with reduced IL-6, IL-10, IL-1β, and TNF-α, along with less damage in lungs and peritoneum in AGUIA vs. AGUIC. These findings suggest the connection between curdlan-produced by A. faecalis A12C-with the immune system and the reduction in severity of experimental sepsis.
PubMed: 38668821
DOI: 10.1007/s12602-024-10252-0 -
Applied Biochemistry and Biotechnology Apr 2024Vanillyl alcohol (VA) possesses potent antioxidant activity, yet its applicability is hindered by its limited solubility in emulsions or non-polar organic solvents....
Vanillyl alcohol (VA) possesses potent antioxidant activity, yet its applicability is hindered by its limited solubility in emulsions or non-polar organic solvents. Conversely, long-chain polyunsaturated fatty acids exhibit antibacterial properties. The combination of these compounds offers the prospect of developing novel phenolic lipid compounds with dual antioxidant and antibacterial activities, alongside enhanced solubility capabilities. In this investigation, linolenic acid vanillyl ester (LAVE) was synthesized from VA and linseed oil (LO) through a transesterification reaction employing immobilized lipase. Optimization of LAVE production was achieved by varying reaction temperature, substrate concentration, and reaction time. LAVE demonstrated efficacy in scavenging both 2,2-diphenyl-1-picryhydrazyl and 2,2'-azino-bis (3-ethylbenthiazoline-6-sulphonic acid) radicals in organic solvents. Antioxidant testing via lipid oxidation analysis revealed that LAVE, when distributed within emulsions, effectively impeded the formation of conjugated dienes and conjugated trienes. Furthermore, LAVE exhibited antibacterial activity against four strains of spoilage bacteria: Bacillus subtilis, Bacillus coagulans, Pseudomonas fluorescens, and Alcaligenes faecalis. Zeta potential analysis substantiated the binding of LAVE to the bacterial cell surface. Propidium iodide uptake assay and fluorescence microscopy further elucidated that LAVE induces cell lysis by augmenting membrane permeability.
PubMed: 38647998
DOI: 10.1007/s12010-024-04945-z -
African Journal of Infectious Diseases 2024Infectious diseases due to antibiotic resistant pathogens are a global public health problem. This study aimed at determining the potential effect of bacterial-fungal...
BACKGROUND
Infectious diseases due to antibiotic resistant pathogens are a global public health problem. This study aimed at determining the potential effect of bacterial-fungal interaction on the antibiotic susceptibility profile of
MATERIALS AND METHODS
was isolated from water samples. The isolate was identified using the conventional biochemical tests and the 16S rRNA molecular sequencing technique. Additionally, species was isolated and identified based on colony morphological characteristics and microscopic features. Standardized isolates were co-cultured in broth medium. Antibiotic susceptibility evaluation of the from the co-culture and the original was carried out using the Kirby bauer disk diffusion method.
RESULTS
The antibiotic susceptibility profile of before and after co-culture remained largely unchanged except in the case of chloramphenicol, where the isolate showed reduced susceptibility. Molecular analysis of resistance gene revealed the absence of tested gene encoding antibiotic resistance, including the streptomycin resistance (str) genes ( and ) and the erythromycin resistance methylase () gene.
CONCLUSION
The result of this study showed that there is a minimal influence of cultures on the susceptibility of . Further research involving a wide spectrum of microorganisms and their interactions should be conducted to acquire a thorough understanding of the influence of microbial interactions on antibiotic susceptibility profiles in order to pave way for novel strategies to combat antimicrobial resistance.
PubMed: 38606189
DOI: 10.21010/Ajidv18i2.2 -
Genome Apr 2024The human gut is the most favorable niche for microbial populations, and few studies have explored the possibilities of horizontal gene transfer between host and...
The human gut is the most favorable niche for microbial populations, and few studies have explored the possibilities of horizontal gene transfer between host and pathogen. Trinucleotide repeat (TNR) expansion in humans can cause more than 40 neurodegenerative diseases. Further, TNRs are a type of microsatellite that resides on coding regions can contribute to the synthesis of homopolymeric amino acids. Hence, the present study aims to estimate the occurrence and diversity of TNRs in bacterial genomes available in the NCBI Genome database. Genome-wide analyses revealed that several bacterial genomes contain different types of uninterrupted TNRs. It was found that TNRs are abundant in the genomes of , and . Interestingly, the genome of strain YBT-1518 contained 169 uninterrupted ATT repeats. The genome of had 46 uninterrupted CAG repeats, which potentially translate into polyglutamine. In some instances, the TNRs were present in genes that potentially encode essential functions. Similar occurrences in human genes are known to cause genetic disorders. Further analysis of the occurrence of TNRs in bacterial genomes is likely to provide a better understanding of mismatch repair, genetic disorders, host-pathogen interaction, and homopolymeric amino acids.
PubMed: 38593473
DOI: 10.1139/gen-2023-0097 -
International Journal of Biological... May 2024The potential to degrade ochratoxin A (OTA), a highly poisonous mycotoxin, was investigated in cultures from Alcaligenes-type strains. Genome sequence analyses from...
The potential to degrade ochratoxin A (OTA), a highly poisonous mycotoxin, was investigated in cultures from Alcaligenes-type strains. Genome sequence analyses from different Alcaligenes species have permitted us to demonstrate a direct, causal link between the gene coding a known N-acyl-L-amino acid amidohydrolase from A. faecalis (AfOTH) and the OTA-degrading activity of this bacterium. In agreement with this finding, we found the gene coding AfOTH in two additional species included in the Alcaligenes genus, namely, A. pakistanensis, and A. aquatilis, which also degraded OTA. Notably, A. faecalis subsp. faecalis DSM 30030 was able to transform OTα, the product of OTA hydrolysis. AfOTH from A. faecalis subsp. phenolicus DSM 16503 was recombinantly over-produced and enzymatically characterized. AfOTH is a Zn-containing metalloenzyme that possesses structural features and conserved residues identified in the M20D family of enzymes. AfOTH is a tetramer in solution that shows both aminoacylase and carboxypeptidase activities. Using diverse potential substrates, namely, N-acetyl-L-amino acids and carbobenzyloxy-L-amino acids, a marked preference towards C-terminal Phe and Tyr residues could be deduced. The structural basis for this specificity has been determined by in silico molecular docking analyses. The amidase activity of AfOTH on C-terminal Phe residues structurally supports its OTA and OTB degradation activity.
Topics: Ochratoxins; Alcaligenes; Amidohydrolases; Substrate Specificity; Amino Acid Sequence; Structure-Activity Relationship
PubMed: 38574921
DOI: 10.1016/j.ijbiomac.2024.131342 -
Biosensors & Bioelectronics Jul 2024We introduce a versatile method to convert NAD or NADP -dependent dehydrogenases into quasi-direct electron transfer (quasi-DET)-type dehydrogenases, by modifying with a...
We introduce a versatile method to convert NAD or NADP -dependent dehydrogenases into quasi-direct electron transfer (quasi-DET)-type dehydrogenases, by modifying with a mediator on the enzyme surface toward the development of 2.5 generation enzymatic sensors. In this study, we use β-hydroxybutyrate (BHB) dehydrogenase (BHBDh) from Alcaligenes faecalis (AfBHBDh) as a representative NAD or NADP -dependent dehydrogenase. BHBDhs are important in ketone monitoring, especially for the diagnosis of diabetic ketoacidosis. We modified AfBHBDh with a thiol-reactive phenazine ethosulfate (trPES). We designed, constructed, and modified mutant BHBDhs harboring cysteine residues within 20 Å from the C4 nicotinamide in NAD/NADH. Mutants Ser65Cys, Thr96Cys, and Lys106Cys showed indistinguishable catalytic activities from the wild-type enzyme, even after trPES modification. These trPES-modified mutants were immobilized on gold disk electrodes via amine coupling with succinimide-groups of dithiobis (succinimidyl hexanoate) self-assembled monolayers for electrochemical measurements. Considering there is a wide range of BHB concentrations, we exploited the linear regression in log scales. The linear range for the sensors with trPES-modified BHBDh mutants Ser65Cys, Thr96Cys, and Lys106Cys were 0.1-4.0 mM in both buffer solution and artificial interstitial fluid (ISF). They have limits of detection of 0.047 mM for Ser65Cys, 0.15 mM for Thr96Cys, and 0.060 mM for Lys106Cys in buffer solution, and 0.12 mM, 0.089 mM, and 0.044 mM in artificial ISF, respectively. These results indicate that redox mediator modification of NAD(P)-dependent dehydrogenases converts them into quasi-DET-type dehydrogenases, thereby enabling their utilization in 2.5 generation enzymatic sensors, which will facilitate the construction of enzymatic sensors suitable for continuous monitoring systems.
Topics: Glucose; NAD; Electrons; NADP; Biosensing Techniques; Oxidoreductases
PubMed: 38552525
DOI: 10.1016/j.bios.2024.116219 -
Journal of Veterinary Research Mar 2024Since the middle of the 1980s, severe skin disorders have been observed in Baltic cod () each year. Available data on the spectrum of bacteria isolated from the clinical...
INTRODUCTION
Since the middle of the 1980s, severe skin disorders have been observed in Baltic cod () each year. Available data on the spectrum of bacteria isolated from the clinical cases being limited, and evaluation of the microbial background of fish skin lesions being useful, a bacteriological examination has been undertaken.
MATERIAL AND METHODS
A total of 1,381 cod were caught during two voyages of the Baltica research vessel in the Polish exclusive economic zone of the southern Baltic Sea. After an examination which found lesions in 164 of the fish, a microbiological analysis was performed to isolate bacteria from them. The collected strains were phenotyped and genotyped, and their antimicrobial resistance was analysed by minimum inhibitory concentration (MIC) techniques.
RESULTS
Bacteriological examinations provided 850 isolates. The dominant microorganisms were mesophilic spp., spp. and . Opportunistic bacteria potentially hazardous to human health were also isolated, . , , and sp. The MIC analysis determined the highest number of bacteria to resist sulphamethoxazole and amoxicillin and clavulanic acid.
CONCLUSION
Most of the collected bacteria were opportunistic pathogens for fish, widespread in the aquatic environment, and potentially threatening to humans.
PubMed: 38525229
DOI: 10.2478/jvetres-2024-0004