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New Microbes and New Infections Sep 2020Multiple studies have established the contamination of hospital sinks and transmission to hospital personnel. Few studies have assessed the contamination and...
Multiple studies have established the contamination of hospital sinks and transmission to hospital personnel. Few studies have assessed the contamination and transmission of microorganisms from the faucets of operating bay scrub sinks to operating room (OR) personnel, a potential route of infection for patients. This study aimed to investigate if there was pathogenic contamination of scrub sinks and possible transmission of those pathogens to the hands of OR personnel after preoperative hand disinfection. Swabs were taken from the hands of 50 OR personnel and from the faucets of 24 scrubs sinks at two different hospital sites, and were cultured. Hands were swabbed after completing a surgical hand scrub. Results were reported in colony-forming units per millilitre. There was significant scrub sink contamination with primarily Gram-negative organisms, such as and . There was no overlap in bacterial species between the cultures from hands and scrub sinks. Cultures from the sinks and the hands of the OR personnel from one site had significantly higher bacterial growth compared with the other site (p < 0.0001 and p < 0.0118, respectively). The data showed significant contamination on the faucets of operating bay scrub sinks. However, there was no observed transmission of pathogens from the scrub sinks to OR personnel, shown by the lack of overlap in bacterial species. Routine hygienic maintenance of scrub sinks is recommended.
PubMed: 32995014
DOI: 10.1016/j.nmni.2020.100754 -
The Science of the Total Environment Feb 2024Fungicide carboxin was commonly used in the form of seed coating for the prevention of smut, wheat rust and cotton damping-off, leading carboxin and its probable...
Fungicide carboxin was commonly used in the form of seed coating for the prevention of smut, wheat rust and cotton damping-off, leading carboxin and its probable carcinogenic metabolite aniline to directly enter the soil with the seeds, causing residual pollution. In this study, a novel carboxin degrading strain, Delftia sp. HFL-1, was isolated. Strain HFL-1 could use carboxin as the carbon source for growth and completely degrade 50 mg/L carboxin and its metabolite aniline within 24 h. The optimal temperatures and pH for carboxin degrading by strain HFL-1 were 30 to 42 °C and 5 to 9, respectively. Furthermore, the complete mineralization pathway of carboxin by strain HFL-1 was revealed by High Resolution Mass Spectrometer (HRMS). Carboxin was firstly hydrolyzed into aniline and further metabolized into catechol through multiple oxidation processes, and finally converted into 4-hydroxy-2-oxopentanoate, a precursor of the tricarboxylic acid cycle. Genome sequencing revealed the corresponding degradation genes and cluster of carboxin. Among them, amidohydrolase and dioxygenase were key enzymes involved in the degradation of carboxin and aniline. The discovery of transposons indicated that the aniline degradation gene cluster in strain HFL-1 was obtained via horizontal transfer. Furthermore, the degradation genes were cloned and overexpressed. The in vitro test showed that the expressed degrading enzyme could efficiently degrade aniline. This study provides an efficient strain resource for the bioremediation of carboxin and aniline in contaminated soil, and further revealing the molecular mechanism of biodegradation of carboxin and aniline.
Topics: Carboxin; Fungicides, Industrial; Biodegradation, Environmental; Delftia; Aniline Compounds; Soil
PubMed: 38030002
DOI: 10.1016/j.scitotenv.2023.168957 -
Journal of Basic Microbiology Jan 2021The residual erythromycin in fermentation waste can pollute the environment and threaten human health. However, there are no effective approaches to remedy this issue....
The residual erythromycin in fermentation waste can pollute the environment and threaten human health. However, there are no effective approaches to remedy this issue. In this study, an erythromycin-degrading bacterium named RJJ-61 was isolated and identified as a strain of Delftia lacustris based on morphological and phylogenetic analyses. The degradation ability of this strain was also evaluated; it could degrade 45.18% of erythromycin at 35°C in 120 h. Furthermore, the key degradation gene ereA was cloned from strain RJJ-61 and expressed in Escherichia coli BL21; the molecular weight of the expressed protein was ~45 kDa. The enzyme activity of EreA was 108.0 mU ml at 35°C and pH 7.0. Finally, the EreA protein was used to degrade erythromycin from mycelial dregs and 50% diluted solution, and the removal rates in them were 41.42% and 69.78%, respectively. In summary, D. lacustris RJJ-61 is a novel erythromycin-degrading strain that has great potential to remove erythromycin pollutants from the environment.
Topics: Bacterial Proteins; Biodegradation, Environmental; Carboxylic Ester Hydrolases; Delftia; Environmental Pollutants; Erythromycin; Escherichia coli; Hydrogen-Ion Concentration; Phylogeny; Recombinant Proteins; Sewage; Temperature
PubMed: 33332633
DOI: 10.1002/jobm.202000613 -
Plants (Basel, Switzerland) Mar 2023Europe's forests, particularly in Ukraine, are highly vulnerable to climate change. The maintenance and improvement of forest health are high-priority issues, and...
Europe's forests, particularly in Ukraine, are highly vulnerable to climate change. The maintenance and improvement of forest health are high-priority issues, and various stakeholders have shown an interest in understanding and utilizing ecological interactions between trees and their associated microorganisms. Endophyte microbes can influence the health of trees either by directly interacting with the damaging agents or modulating host responses to infection. In the framework of this work, ten morphotypes of endophytic bacteria from the tissues of unripe acorns of L. were isolated. Based on the results of the sequenced 16S rRNA genes, four species of endophytic bacteria were identified: , , , and . Determining the activity of pectolytic enzymes showed that the isolates and could not cause maceration of plant tissues. Screening for these isolates revealed their fungistatic effect against phytopathogenic micromycetes, namely , , and . Inoculation of , , and their complex in oak leaves, in contrast to phytopathogenic bacteria, contributed to the complete restoration of the epidermis at the sites of damage. The phytopathogenic bacteria and caused a 2.0 and 2.2 times increase in polyphenol concentration in the plants, respectively, while the ratio of antioxidant activity to total phenolic content decreased. Inoculation of and isolates into oak leaf tissue were accompanied by a decrease in the total pool of phenolic compounds. The ratio of antioxidant activity to total phenolic content increased. This indicates a qualitative improvement in the overall balance of the oak leaf antioxidant system induced by potential PGPB. Thus, endophytic bacteria of the genus isolated from the internal tissues of unripe oak acorns have the ability of growth biocontrol and spread of phytopathogens, indicating their promise for use as biopesticides.
PubMed: 36987039
DOI: 10.3390/plants12061352 -
Environmental Microbiology Mar 2022Bacterial wilt disease caused by Ralstonia solanacearum leads to decrease of crops yield. Investigation of cultivable bacteria diversity provides more microbial species...
Bacterial wilt disease caused by Ralstonia solanacearum leads to decrease of crops yield. Investigation of cultivable bacteria diversity provides more microbial species for screening antagonistic bacteria. In the present study, a variety of cultivation methods were used to investigate the diversity of cultivable bacteria alive in tobacco field. A total of 441 bacterial strains were obtained that belonged to four phyla, 49 genera and 146 species. Actinobacteria and Proteobacteria were the dominant phyla. Agrobacterium, Arthrobacter, Bacillus, Klebsiella, Paenarthrobacter, Pseudomonas and Pseudarthrobacter were the dominant genera. Some rare genera were discovered including Bosea, Cedecea, Delftia and Dyella. Diversity, species and abundances of bacteria altered under different cultivation conditions. One hundred three bacterial strains showed plant growth-promoting attributes. Twenty Bacillus strains showed high antibacterial activity against R. solanacearum. In field experiments, individual strain and consortia of Bacillus subtilis, B. siamensis and B. vallismortis effectively inhibited bacterial wilt. The core genes that controlled synthesis of secondary metabolites were knocked out in B. vallismortis SSB-10. Difficidin, which was synthesized by dif operon and controlled by sfp gene, was the antibacterial substance produced by SSB-10. Difficidin destroyed cell wall and cell membrane of R. solanacearum and inhibited its motility, production of extracellular polysaccharides and cellulase activity.
Topics: Anti-Bacterial Agents; Bacillus; Bacillus subtilis; Plant Diseases; Ralstonia solanacearum; Nicotiana
PubMed: 35112429
DOI: 10.1111/1462-2920.15868 -
NPJ Biofilms and Microbiomes Feb 2020The microbiota colonizing the root endophytic compartment and surrounding rhizosphere soils contribute to plant growth and health. However, the key members of plant soil...
The microbiota colonizing the root endophytic compartment and surrounding rhizosphere soils contribute to plant growth and health. However, the key members of plant soil and endophytic microbial communities involved in inhibiting or assisting pathogen invasion remain elusive. By utilizing 16S high-throughput sequencing and a molecular ecological network (MEN) approach, we systematically studied the interactions within bacterial communities in plant endophytic compartments (stem and root) and the surrounding soil (bulk and rhizosphere) during bacterial wilt invasion. The endophytic communities were found to be strongly influenced by pathogen invasion according to analysis of microbial diversity and community structure and composition. Endophytic communities of the infected plants were primarily derived from soil communities, as assessed by the SourceTracker program, but with rare migration from soil communities to endophytic communities observed in healthy plants. Soil and endophytic microbiomes from infected plants showed modular topology and greater complexity in network analysis, and a higher number of interactions than those in healthy plants. Furthermore, interactions among microbial members revealed that pathogenic Ralstonia members were positively correlated with several bacterial genera, including Delftia, Stenotrophomonas, Bacillus, Clostridium XlVa, Fontibacillus, Acidovorax, Herminiimonas, and three unclassified bacterial genera, in infected plant roots. Our findings indicated that the pathogen invasion in the rhizosphere and endophytic compartments may be highly associated with bacteria that are normally not detrimental, and sometimes even beneficial, to plants.
Topics: Bacteria; DNA, Bacterial; DNA, Ribosomal; High-Throughput Nucleotide Sequencing; Phylogeny; Plant Diseases; Plant Roots; RNA, Ribosomal, 16S; Rhizosphere; Sequence Analysis, DNA; Soil Microbiology; Nicotiana
PubMed: 32060424
DOI: 10.1038/s41522-020-0117-2 -
Microbiology Spectrum Apr 2022Delftia tsuruhatensis strains have long been known to promote plant growth and biological control. Recently, it has become an emerging opportunistic pathogen in humans....
Delftia tsuruhatensis strains have long been known to promote plant growth and biological control. Recently, it has become an emerging opportunistic pathogen in humans. However, the genomic characteristics of the genetic diversity, pathogenicity, and biotechnological properties have not yet been comprehensively investigated. Here, a comparative pan-genome analysis was constructed. The open pan-genome with a large and flexible gene repertoire exhibited a high degree of genetic diversity. The purifying selection was the main force to drive pan-genome evolution. Significant differences were observed in the evolutionary relationship, functional enrichment, and degree of selective pressure between the different components of the pan-genome. A high degree of genetic plasticity was characterized by the determinations of diverse mobile genetic elements (MGEs), massive genomic rearrangement, and horizontal genes. Horizontal gene transfer (HGT) plays an important role in the genetic diversity of this bacterium and the formation of genomic traits. Our results revealed the occurrence of diverse virulence-related elements associated with macromolecular secretion systems, virulence factors associated with multiple nosocomial infections, and antimicrobial resistance, indicating the pathogenic potential. Lateral flagellum, T1SS, T2SS, T6SS, Tad pilus, type IV pilus, and a part of virulence-related genes exhibited general properties, whereas polar flagellum, T4SS, a part of virulence-related genes, and resistance genes presented heterogeneous properties. The pan-genome also harbors abundant genetic traits related to secondary metabolism, carbohydrate active enzymes (CAZymes), and phosphate transporter, indicating rhizosphere adaptation, plant growth promotion, and great potential uses in agriculture and biological control. This study provides comprehensive insights into this uncommon species from the genomic perspective. D. tsuruhatensis is considered a plant growth-promoting rhizobacterium (PGPR), an organic pollutant degradation strain, and an emerging opportunistic pathogen to the human. However, the genetic diversity, the evolutionary dynamics, and the genetic basis of these remarkable traits are still little known. We constructed a pan-genome analysis for D. tsuruhatensis and revealed extensive genetic diversity and genetic plasticity exhibited by open pan-genome, diverse mobile genetic elements (MGEs), genomic rearrangement, and horizontal genes. Our results highlight that horizontal gene transfer (HGT) and purifying selection are important forces in D. tsuruhatensis genetic evolution. The abundant virulence-related elements associated with macromolecular secretion systems, virulence factors, and antimicrobial resistance could contribute to the pathogenicity of this bacterium. Therefore, clinical microbiologists need to be aware of D. tsuruhatensis as an opportunistic pathogen. The genetic profiles of secondary metabolism, carbohydrate active enzymes (CAZymes), and phosphate transporter could provide insight into the genetic armory of potential applications for agriculture and biological control of D. tsuruhatensis in general.
Topics: Anti-Infective Agents; Delftia; Genetic Variation; Genome, Bacterial; Humans; Phosphate Transport Proteins; Phylogeny; Virulence; Virulence Factors
PubMed: 35230132
DOI: 10.1128/spectrum.02072-21 -
PloS One 2020The metal hyperaccumulator Azolla filiculoides is accompanied by a microbiome potentially supporting plant during exposition to heavy metals. We hypothesized that the...
The metal hyperaccumulator Azolla filiculoides is accompanied by a microbiome potentially supporting plant during exposition to heavy metals. We hypothesized that the microbiome exposition to selected heavy metals will reveal metal tolerant strains. We used Next Generation Sequencing technique to identify possible metal tolerant strains isolated from the metal-treated plant (Pb, Cd, Cr(VI), Ni, Au, Ag). The main dominants were Cyanobacteria and Proteobacteria constituting together more than 97% of all reads. Metal treatment led to changes in the composition of the microbiome and showed significantly higher richness in the Pb-, Cd- and Cr-treated plant in comparison with other (95-105 versus 36-44). In these treatments the share of subdominant Actinobacteria (0.4-0.8%), Firmicutes (0.5-0.9%) and Bacteroidetes (0.2-0.9%) were higher than in non-treated plant (respectively: 0.02, 0.2 and 0.001%) and Ni-, Au- and Ag-treatments (respectively: <0.4%, <0.2% and up to 0.2%). The exception was Au-treatment displaying the abundance 1.86% of Bacteroidetes. In addition, possible metal tolerant genera, namely: Acinetobacter, Asticcacaulis, Anabaena, Bacillus, Brevundimonas, Burkholderia, Dyella, Methyloversatilis, Rhizobium and Staphylococcus, which form the core microbiome, were recognized by combining their abundance in all samples with literature data. Additionally, the presence of known metal tolerant genera was confirmed: Mucilaginibacter, Pseudomonas, Mycobacterium, Corynebacterium, Stenotrophomonas, Clostridium, Micrococcus, Achromobacter, Geobacter, Flavobacterium, Arthrobacter and Delftia. We have evidenced that A. filiculoides possess a microbiome whose representatives belong to metal-resistant species which makes the fern the source of biotechnologically useful microorganisms for remediation processes.
Topics: Actinobacteria; Bacteroidetes; Biodegradation, Environmental; Cadmium; Chromium; DNA, Bacterial; Ferns; Firmicutes; High-Throughput Nucleotide Sequencing; Lead; Microbiota; RNA, Ribosomal, 16S; Soil Microbiology; Soil Pollutants
PubMed: 32374760
DOI: 10.1371/journal.pone.0232699 -
Life (Basel, Switzerland) Oct 2022Agarwood () is one of the most important resin-containing plants used to produce agar around the world and it is a precious herbal medicine usually combined with other...
Agarwood () is one of the most important resin-containing plants used to produce agar around the world and it is a precious herbal medicine usually combined with other herbs. In this study, we used the Illumina sequencing technique to explore the agarwood bacterial community structure from four different incense formations of agarwood, including healthy agarwood, drilling agarwood, liquid fermentation agarwood, and insect attack agarwood. Our results showed that 20 samples of three different incense-formation methods of agarwood and healthy agarwood acquired 1,792,706 high-quality sequences. In-depth investigation showed that when the diversity of agarwood bacterial species was higher, the agarwood incense quality was higher as well. Among healthy agarwood, drilling agarwood, fermentation agarwood, and insect attack agarwood, the bacterial community structure had significant changes. Natural agarwood, such as insect attack agarwood, kept more bacterial community structure, and the incense quality was better. Furthermore, we observed that in the healthy agarwood, and were the predominant bacteria. , , and were the dominant bacteria in the drilling agarwood. Additionally, and were some of the main bacteria in the fermentation liquid agarwood and the insect attack agarwood, while and were the dominant bacteria. This research provides a basis for further research into the underlying mechanisms of incense production, as well as the bacterial community applications of agarwood production.
PubMed: 36362852
DOI: 10.3390/life12111697 -
BMJ Case Reports Oct 2023A term neonate weighing 2900 g was referred in the first week of life with complaints of abdominal distension since birth. New onset respiratory distress was noted 36...
A term neonate weighing 2900 g was referred in the first week of life with complaints of abdominal distension since birth. New onset respiratory distress was noted 36 hours prior to referral. Baby required non-invasive respiratory support and intravenous antibiotics as chest X-ray was suggestive of pneumonia. Ultrasound abdomen confirmed low ano-rectal malformation treated with cut-back anoplasty. Blood culture on admission grew a rare organism The antibiotics were tailored as per the sensitivity pattern and continued for a duration of 14 days. Respiratory distress gradually resolved by day 10 of admission. The baby developed pneumonia after 36 hours of stay in the referring hospital; most probably indicating a hospital acquired source of this pathogen. To the best of our knowledge, this is the second reported neonatal case of sepsis.
Topics: Infant, Newborn; Humans; Delftia acidovorans; Cross Infection; Sepsis; Anti-Bacterial Agents; Pneumonia; Healthcare-Associated Pneumonia
PubMed: 37827711
DOI: 10.1136/bcr-2023-256439