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ACS Omega Jan 2024The goal behind this work is to prepare, characterize, and study the antimicrobial behavior of zirconia (ZrO) nanoparticles (NPs). Various techniques, such as X-ray...
The goal behind this work is to prepare, characterize, and study the antimicrobial behavior of zirconia (ZrO) nanoparticles (NPs). Various techniques, such as X-ray diffraction (XRD), were used for studying the mineralogical structure and crystal size. The microstructure and chemical composition of the prepared particles were analyzed using a scanning electron microscope attached with an energy-dispersive X-ray analysis (EDAX) unit. The antagonistic ability against several Gram-negative and Gram-positive bacteria, including , and , was assessed using the well diffusion method. The results of XRD and scanning electron microscopy (SEM) analyses revealed that the prepared material exhibited the phase of zirconium nanoparticles with particle sizes ranging between 40 and 75 nm. The antimicrobial test results demonstrated that the inhibitory effect increased with the increase of concentration. The inhibitory effect was more pronounced against Gram-positive bacteria, as indicated by the larger size of the inhibitory zone. At a 9% dimethyl sulfoxide (DMSO) concentration, the inhibitory zone had a diameter of 3.50 mm for compared to a diameter of 3.40 mm for . The use of zirconium oxide nanoparticles reduced the diameter of the inhibitory zone when tested against at a 3% DMSO concentration (0.50 mm diameter) and against (0.40 mm diameter). Zirconia nanoparticles were also evaluated for their antifungal activity against several species, including , , and sp. The size of the inhibitory zone indicated the susceptibility of microorganisms to nanozirconium oxide, resulting in a stronger inhibition of sp. at a 100% DMSO concentration (4.50 mm diameter) compared to and (3.00 mm diameter). The results for sp. at a 3% DMSO concentration showed a diameter of the inhibitory zone of 0.90 mm, while for and , the diameter was 0.80 mm. Thus, our findings demonstrate that the zirconium oxide nanoparticles possess the capability to reduce the inhibition zone effectively for both bacterial and fungal activities.
PubMed: 38250396
DOI: 10.1021/acsomega.3c08580 -
Frontiers in Microbiology 2023Genus is a large assemblage of diverse microorganisms, not sharing a common evolutionary history. To clarify their evolutionary relationships and classification, we...
Genus is a large assemblage of diverse microorganisms, not sharing a common evolutionary history. To clarify their evolutionary relationships and classification, we have conducted comprehensive phylogenomic and comparative analyses on 388 genomes. In phylogenomic trees, species formed 12 main clusters, apart from the "Aeruginosa clade" containing its type species, . In parallel, our detailed analyses on protein sequences from genomes have identified 98 novel conserved signature indels (CSIs), which are uniquely shared by the species from different observed clades/groups. Six CSIs, which are exclusively shared by species from the "Aeruginosa clade," provide reliable demarcation of this clade corresponding to the genus in molecular terms. The remaining 92 identified CSIs are specific for nine other species clades and the genera and which branch in between them. The identified CSIs provide strong independent evidence of the genetic cohesiveness of these species clades and offer reliable means for their demarcation/circumscription. Based on the robust phylogenetic and molecular evidence presented here supporting the distinctness of the observed species clades, we are proposing the transfer of species from the following clades into the indicated novel genera: Alcaligenes clade - gen. nov.; Fluvialis clade - gen. nov.; Linyingensis clade - gen. nov.; Oleovorans clade - gen. nov.; Resinovorans clade - gen. nov.; Straminea clade - gen. nov.; and Thermotolerans clade - gen. nov. In addition, descriptions of the genera , , , and are emended to include information for the CSIs specific for them. The results presented here should aid in the development of a more reliable classification scheme for species.
PubMed: 38249459
DOI: 10.3389/fmicb.2023.1273665 -
BioMed Research International 2024Chlorpyrifos (CP) is a chlorinated organophosphate pesticide. In Kenya, it is commonly used as an acaricide, particularly in dairy farming, leading to soil and water...
Chlorpyrifos (CP) is a chlorinated organophosphate pesticide. In Kenya, it is commonly used as an acaricide, particularly in dairy farming, leading to soil and water contamination. The study is aimed at isolating bacteria with CP-degrading potential and optimizing their growth conditions, including temperature, pH, and CP concentration. The enrichment culture technique was used, with minimal salt medium (MSM) supplemented with commercial grade CP. A multilevel factorial design was used to investigate the interactions of temperature, pH, and CP concentration. According to the findings, seven bacterial strains with potential to degrade CP were characterized and identified as , , , sp. strain , sp. strain , , and clone 99. Growth and biodegradation of bacteria differed significantly among the isolates across pH value, temperature, and concentrations ( ≤ 0.05). The optimum conditions for growth were pH 7, temperature of 25°C, and 25mg/l chlorpyrifos concentration, while optimum degradation conditions were pH 5, temp 25°C, and CP conc. 25mg/l. The Pearson correlation between optimum growth and degradation showed a weak positive relationship ( = 0.1144) for pH and strong positive relationship for temperature and concentration of chlorpyrifos. Other than pH, the study shows that there could be other cofactors facilitating the chlorpyrifos degradation process. The findings show that an efficient consortium, at 25°C and pH 5, can include and sp. as they showed high optical density (OD) values under these conditions. These results indicate the potential for these bacteria to be employed in chlorpyrifos-contaminated ecosystem detoxification efforts upon manipulation of natural growth conditions. The findings of this study offer a potential foundation for future research into the reconstitution of a consortium. Based on the optimum conditions identified, the isolated bacterial strains could be further developed into a consortium to effectively degrade CP in both laboratory and field conditions. Dairy farmers can utilize the isolated strains and the consortia to decontaminate farm soils.
Topics: Chlorpyrifos; Soil; Farms; Kenya; Ecosystem; Bacteria; Biodegradation, Environmental; Pseudomonas; Soil Microbiology; Bacillus
PubMed: 38304346
DOI: 10.1155/2024/1611871 -
PloS One 2024Dysbiotic biliary bacterial profile is reported in cancer patients and is associated with survival and comorbidities, raising the question of its effect on the influence...
BACKGROUND
Dysbiotic biliary bacterial profile is reported in cancer patients and is associated with survival and comorbidities, raising the question of its effect on the influence of anticancer drugs and, recently, the suggestion of perichemotherapy antibiotics in pancreatic cancer patients colonized by the Escherichia coli and Klebsiella pneumoniae.
OBJECTIVE
In this study, we investigated the microbial communities that colonize tumours and which bacteria could aid in diagnosing pancreatic and biliary cancer and managing bile-colonized patients.
METHODS
A retrospective study on positive bile cultures of 145 Italian patients who underwent cholangiopancreatography with PC and EPC cancer hospitalized from January 2006 to December 2020 in a QA-certified academic surgical unit were investigated for aerobic/facultative-anaerobic bacteria and fungal organisms.
RESULTS
We found that among Gram-negative bacteria, Escherichia coli and Pseudomonas spp were the most frequent in the EPC group, while Escherichia coli, Klebsiella spp, and Pseudomonas spp were the most frequent in the PC group. Enterococcus spp was the most frequent Gram-positive bacteria in both groups. Comparing the EPC and PC, we found a significant presence of patients with greater age in the PC compared to the EPC group. Regarding Candida spp, we found no significant but greater rate in the PC group compared to the EPC group (11.7% vs 1.96%). We found that Alcaligenes faecalis was the most frequent bacteria in EPC than the PC group, among Gram-negative bacterial species.
CONCLUSIONS
Age differences in gut microbiota composition may affect biliary habitats in our cancer population, especially in patients with pancreatic cancer. Alcaligenes faecalis isolated in the culture of bile samples could represent potential microbial markers for a restricted follow-up to early diagnosis of extra-pancreatic cancer. Finally, the prevalence of Candida spp in pancreatic cancer seems to trigger new aspects about debate about the role of fungal microbiota into their relationship with pancreatic cancer.
Topics: Humans; Bile; Retrospective Studies; Bacteria; Anti-Bacterial Agents; Gram-Negative Bacteria; Biliary Tract Neoplasms; Candida; Escherichia coli; Pancreatic Neoplasms; Microbial Sensitivity Tests
PubMed: 38381746
DOI: 10.1371/journal.pone.0294049 -
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 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 -
Microbiological Research May 2024The root microbiota plays a crucial role in plant performance. The use of microbial consortia is considered a very useful tool for studying microbial interactions in the...
The root microbiota plays a crucial role in plant performance. The use of microbial consortia is considered a very useful tool for studying microbial interactions in the rhizosphere of different agricultural crop plants. Thus, a consortium of 3 compatible beneficial rhizospheric Pseudomonas strains previously isolated from the avocado rhizosphere, was constructed. The consortium is composed of two compatible biocontrol P. chlororaphis strains (PCL1601 and PCL1606), and the biocontrol rhizobacterium Pseudomonas alcaligenes AVO110, which are all efficient root colonizers of avocado and tomato plants. These three strains were compatible with each other and reached stable levels both in liquid media and on plant roots. Bacterial strains were fluorescent tagged, and colonization-related traits were analyzed in vitro, revealing formation of mixed biofilm networks without exclusion of any of the strains. Additionally, bacterial colonization patterns compatible with the different strains were observed, with high survival traits on avocado and tomato roots. The bacteria composing the consortium shared the same root habitat and exhibited biocontrol activity against soil-borne fungal pathogens at similar levels to those displayed by the individual strains. As expected, because these strains were isolated from avocado roots, this Pseudomonas-based consortium had more stable bacterial counts on avocado roots than on tomato roots; however, inoculation of tomato roots with this consortium was shown to protect tomato plants under high-temperature stress. The results revealed that this consortium has side beneficial effect for tomato plants under high-temperature stress, thus improving the potential performance of the individual strains. We concluded that this rhizobacterial consortium do not improve the plant protection against soil-borne phytopathogenic fungi displayed by the single strains; however, its inoculation can show an specific improvement of plant performance on a horticultural non-host plant (such as tomato) when the plant was challenged by high temperature stress, thus extending the beneficial role of this bacterial consortium.
PubMed: 38761488
DOI: 10.1016/j.micres.2024.127761 -
Food Chemistry: X Oct 2023In this study, the bacterial communities and flavor metabolites of 27 traditional naturally fermented sauerkraut samples collected from nine regions of Heilongjiang...
Exploring potential correlations between bacterial communities, organic acids, and volatile metabolites of traditional fermented sauerkraut collected from different regions of Heilongjiang Province in Northeast China.
In this study, the bacterial communities and flavor metabolites of 27 traditional naturally fermented sauerkraut samples collected from nine regions of Heilongjiang Province in Northeast China were investigated. The dominant genera were , , , , , , , , , and . A total of 148 volatile compounds were detected in seven categories; esters and acids were the most abundant volatiles. Additionally, the highest content (15.96 mg/g) of lactic acid was detected in YC1. Acetic acid, oleic acid, palmitic acid, elaidic acid, and dehydroacetic acid were the key differential volatile compounds, which may be related to the bacterial communities. Spearman's correlation analysis revealed that and were significantly positively correlated with flavor metabolites, suggesting that they may play a more significant role in flavor formation. The results of this study can help in the development of better quality of fermented vegetables.
PubMed: 37680758
DOI: 10.1016/j.fochx.2023.100840 -
International Journal of Microbiology 2023Rhizobial nitrogen-fixing bacteria are the main inhabitants of the root nodules of legume plants. Studying the bacterial community of legume nodules is important in...
Rhizobial nitrogen-fixing bacteria are the main inhabitants of the root nodules of legume plants. Studying the bacterial community of legume nodules is important in understanding plant growth and nutrient requirements. Culture-based technique was used to examine the bacterial community of these underground organs from L. Verdc (Bambara nut), an underutilized legume in Africa, for plant growth-promoting traits. In this study, Bambara nuts were planted to trap root-nodule bacteria, and the bacteria were morphologically, biochemically, and molecularly characterized. Five selected isolates were screened for their plant growth-promoting traits and exhibited differences in their phenotypic traits. The polymerase chain reaction (PCR) products were subjected to partial 16S rRNA gene sequencing for phylogenetic analysis. Based on 16S rRNA gene sequence, the isolates were identified as BA1 (), BA2 ( sp.), BA3 (), BA4 (), and BA5 (). Results showed that four of the five isolates could produce IAA. The capability to solubilize phosphate in Pikovskaya's agar plates was positively shown by four isolates (BA2, BA3, BA4, and BA5). Three isolates could produce hydrogen cyanide while isolates BA1, BA3, BA4, and BA5 were found to have ammonia-production traits. The results suggest that these plant growth-promoting isolates can be used as inoculants for plant growth and productivity.
PubMed: 37426699
DOI: 10.1155/2023/8218721