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Heliyon Mar 2024Methyl orange (MO) is commonly used in the textile dyeing industry, posing serious health and environmental hazards due to its carcinogenic, mutagenic properties, and...
Methyl orange (MO) is commonly used in the textile dyeing industry, posing serious health and environmental hazards due to its carcinogenic, mutagenic properties, and potential for bioaccumulation. Appropriate handling is needed to solve these problems by harnessing the capacity of living microorganisms and the adsorption properties of bentonite clay minerals. Although the conventional approach predominantly depends on free cells, recent study has developed other methods such as immobilization techniques. Therefore, this study aimed to investigate the efficiency of the immobilization matrix comprising sodium alginate (SA), polyvinyl alcohol (PVA), and bentonite by modifying , , and for MO removal of 50 mg/L. In the free cell technique, the results showed that the MO decreased to 43.13, 36.61, and 27.45% for each of the bacteria within 10 days at 35 °C. The bacterial immobilization technique, including live immobilized (LIPa), live immobilized (LIBs), and live immobilized (LIRp) beads also demonstrated significant efficiency, achieving MO removal rates up to 97.15, 95.65, and 66.63% within 10 days. These synthesized beads showed reusability, with LIPa, LIBs, and LIRp being used up to 4, 4, and 2 cycles, respectively. The external and internal surface conditions were observed using SEM instrument and the results showed that all components were agglomerated. Comparisons using dead bacterial biomass indicated that treatment with live bacteria consistently yielded significantly higher removal rates. These results showed the effectiveness of immobilized bacteria in MO removal, offering a promising potential in reducing pollutants.
PubMed: 38533018
DOI: 10.1016/j.heliyon.2024.e27871 -
BMC Infectious Diseases Mar 2024Ralstonia pickettii is a low virulent, gram-negative bacillus that is rarely associated with human infections and may cause bacteremia. Microbacterium species are...
BACKGROUND
Ralstonia pickettii is a low virulent, gram-negative bacillus that is rarely associated with human infections and may cause bacteremia. Microbacterium species are gram-positive coryneforms that are generally considered as a contaminant in Gram staining of blood cultures, especially when the time to positivity is longer than 48 h. Both these bacterial species are emerging opportunistic pathogens that may occasionally cause serious infections and even life-threatening health conditions.
CASE PRESENTATION
Here, we report the case of a patient with bacteremia caused by both R. pickettii and Microbacterium. We advocate for providers to order rapid antibiotic susceptibility testing, since our patient's suffered two kinds of rare pathogens with the opposite of drug sensitivity results to imipenem.
CONCLUSIONS
Our case present a patient suffered septic shock caused by R. pickettii and Microbacterium. Improving the antibiotic management based on the result of antimicrobial susceptibility tests is the key of successful treatment.
Topics: Humans; Ralstonia pickettii; Microbacterium; Gram-Negative Bacterial Infections; Anti-Bacterial Agents; Bacteremia
PubMed: 38500029
DOI: 10.1186/s12879-024-09228-w -
Frontiers in Microbiology 2023, the most critical clinical pathogen of the genus , has been identified as a causative agent of numerous harmful infections. Additionally, demonstrates adaptability to...
, the most critical clinical pathogen of the genus , has been identified as a causative agent of numerous harmful infections. Additionally, demonstrates adaptability to extreme environmental conditions, such as those found in drinking water. In this study, we conducted a comprehensive genomic analysis to investigate the genomic characteristics related to potential pathogenicity and adaptive evolution in drinking water environments of . Through phylogenetic analysis and population genetic analysis, we divided into five Groups, two of which were associated with drinking water environments. The open pan-genome with a large and flexible gene repertoire indicated a high genetic plasticity. Significant differences in functional enrichment were observed between the core- and pan-genome of different groups. Diverse mobile genetic elements (MGEs), extensive genomic rearrangements, and horizontal gene transfer (HGT) events played a crucial role in generating genetic diversity. In drinking water environments, exhibited strong adaptability, and the acquisition of specific adaptive genes was potentially facilitated by genomic islands (GIs) and HGT. Furthermore, environmental pressures drove the adaptive evolution of , leading to the accumulation of unique mutations in key genes. These mutations may have a significant impact on various physiological functions, particularly carbon metabolism and energy metabolism. The presence of virulence-related elements associated with macromolecular secretion systems, virulence factors, and antimicrobial resistance indicated the potential pathogenicity of , making it capable of causing multiple nosocomial infections. This study provides comprehensive insights into the potential pathogenicity and adaptive evolution of in drinking water environments from a genomic perspective.
PubMed: 38370577
DOI: 10.3389/fmicb.2023.1272636 -
New Microbes and New Infections Mar 2024is a rare Gram-negative opportunistic bacterium that causes rare infections such as bacteremia, neonatal sepsis, endocarditis, and meningitis in hospitalized or...
is a rare Gram-negative opportunistic bacterium that causes rare infections such as bacteremia, neonatal sepsis, endocarditis, and meningitis in hospitalized or immunocompromised patients. In this study, we identified and reported bloodstream infection caused by in a 15 -year-old boy patient with an autoimmune disease, Guillain-Barré syndrome, under plasmapheresis and intravenous immune globulin (IVIG) therapy. He was referred for admission to the neurology center of the teaching hospital of Shiraz, Iran for inability to walk, and lower extremity muscle weakness. After he was treated with plasmapheresis once during hospitalization, and after severe fever besides shivering blood cultures using BACT/ALERT®3D instrument were positive for antibiotic susceptibility test report, 5 μg was prescribed. Fortunately, after starting antibiotic treatment, blood culture results reported no growth after 5 days. Indeed, the patient was infected with nosocomial hepatitis A and URSOBIL (300 mg/BID/Po) was administered. Hence, after reporting the infection occurrence to the hospital infection control unit, initial and possible measures such as device infection control, replacement of potentially polluted plasmapheresis fluids, disinfecting the environment and replacing old sterile washing water with new sources were carried out in plasmapheresis unit. In conclusion, is a rare nosocomial infection that is responsible for the contamination of medical equipment, especially in hemodialysis, plasmapheresis devices and sterile solutions. Also, it is suggested that the role and importance of rare environmental bacteria as the causative agents of human infections should not be ignored in medical centers.
PubMed: 38298270
DOI: 10.1016/j.nmni.2024.101218 -
Euro Surveillance : Bulletin Europeen... Jan 2024is a Gram-negative rod which may cause invasive infections when they contaminate liquid medical products. After was detected in blood cultures and a stem cell product...
is a Gram-negative rod which may cause invasive infections when they contaminate liquid medical products. After was detected in blood cultures and a stem cell product from three patients in a tertiary care hospital in Germany, whole genome sequencing of these three isolates and two water isolates from the environment was performed. Core genome multilocus sequence typing analysis showed that the three patient isolates were closely related and there was a large distance to the environmental isolates. In a genomic comparison, the patients' isolates were distantly related to an strain from a cluster in Australia suspected to be caused by contaminated saline produced in India, while all liquid medical products with a link to all patients were produced in Europe or the United States. Our data point towards an ongoing risk by an unknown common source that could be traced back to medical products contaminated with and potentially distributed worldwide. Investigating invasive infections, identifying and testing medical products administered to the patients and timely whole genome sequencing may help identify the exact source of this potentially global outbreak.
Topics: Humans; Ralstonia pickettii; Saline Solution; Gram-Negative Bacterial Infections; Cross Infection; Sepsis; Genomics; Germany
PubMed: 38240062
DOI: 10.2807/1560-7917.ES.2024.29.3.2400010 -
Frontiers in Microbiology 2023Specific interactions between root exudates and soil microorganisms has been proposed as one of the reasons accounting for the continuous cropping obstacle (CCO) of ....
INTRODUCTION
Specific interactions between root exudates and soil microorganisms has been proposed as one of the reasons accounting for the continuous cropping obstacle (CCO) of . However, rotation of other crops on soils planted with (SPP) did not show CCO, suggesting that root exudates of different crops differentially regulate soil microorganisms in SPP.
METHODS
Here, we investigated the microbial community structure and specific interaction mechanisms of the root exudates of the four plant species, (Pn), (Zm), (Nt) and (Pf), in SPP by static soil culture experiment.
RESULTS
The results showed that the chemical diversity of root exudates varied significantly among the four plant species. Pn had the highest number of unique root exudates, followed by Nt, Zm and Pf. Terpenoids, flavonoids, alkaloids and phenolic acids were the most abundant differentially accumulated metabolites (DAMs) in Pn, Nt, Zm and Pf, respectively. However, lipids were the most abundant common DAMs among Zm Nt and Pf. Pn root exudates decreased the relative abundance of bacteria, but increased that of fungi. While specific DAMs in Pn enriched , , and functional pathways of Nucleotide excision repair, Streptomycin biosynthesis, Cell cycle-Caulobacter and Glycolysis/Gluconeogenesis, it inhibited and . However, common DAMs in Zm, Nt and Pf had opposite effects. Moreover, common DAMs in Zm, Nt and Pf enriched and functional pathway of Xylene degradation; unique DAMs in Zm enriched , while inhibiting and functional pathways of Nucleotide excision repair and Alanine, aspartate and glutamate metabolism; unique DAMs in Pf enriched .
DISCUSSION
The core strains identified that interact with different root exudates will provide key clues for regulation of soil microorganisms in cultivation to alleviate CCO.
PubMed: 38125568
DOI: 10.3389/fmicb.2023.1282689 -
Frontiers in Cellular and Infection... 2023Healthy lung microbiota plays an important role in preventing (Mtb) infections by activating immune cells and stimulating production of T-helper cell type 1 cytokines....
INTRODUCTION
Healthy lung microbiota plays an important role in preventing (Mtb) infections by activating immune cells and stimulating production of T-helper cell type 1 cytokines. The dynamic stability of lung microbiota relies mostly on lung homeostasis. In our previous studies, we found that Mtb virulence factor, Rv1987 protein, can mediate host immune response and enhance mycobacterial survival in host lung. However, the alteration of lung microbiota and the contribution of lung microbiota dysbiosis to mycobacterial evasion in this process are not clear so far.
METHODS
which does not contain the ortholog of Rv1987 protein was selected as a model strain to study the effects of Rv1987 on host lung microbiota. The lung microbiota, immune state and metabolites of mice infected by overexpressing Rv1987 protein (MS1987) were detected and analyzed.
RESULTS
The results showed that Rv1987 inhibited inflammatory response in mouse lung and anaerobic bacteria and , , and bacteria were enriched in the lung tissues correspondingly. The immune alterations and microbiota dysbiosis affected host metabolic profiles, and some of significantly altered bacteria in MS1987-infected mouse lung, such as , and , led to anti-inflammatory responses in mouse lung. The secretory metabolites of these altered bacteria also influenced mycobacterial growth and biofilm formation directly.
CONCLUSION
All these results suggested that Rv1987 can attenuate inflammatory response and alter microbiota in the lung, which in turn facilitates mycobacterial survival in the host.
Topics: Animals; Mice; Mycobacterium tuberculosis; Dysbiosis; Cytokines; Mycobacterium Infections; Lung; Microbiota
PubMed: 38029253
DOI: 10.3389/fcimb.2023.1256866 -
ISME Communications Nov 2023Due to the wide use of antibiotics, intensive aquaculture farms have been recognized as a significant reservoir of antibiotic resistomes. Although the prevalence of...
Due to the wide use of antibiotics, intensive aquaculture farms have been recognized as a significant reservoir of antibiotic resistomes. Although the prevalence of colistin resistance genes and multidrug-resistant bacteria (MDRB) has been documented, empirical evidence for the transmission of colistin and multidrug resistance between bacterial communities in aquaculture farms through horizontal gene transfer (HGT) is lacking. Here, we report the prevalence and transmission risk of colistin and multidrug resistance in 27 aquaculture water samples from 9 aquaculture zones from over 5000 km of subtropical coastlines in southern China. The colistin resistance gene mcr-1, mobile genetic element (MGE) intl1 and 13 typical antibiotic resistance genes (ARGs) were prevalent in all the aquaculture water samples. Most types of antibiotic (especially colistin) resistance are transmissible in bacterial communities based on evidence from laboratory conjugation and transformation experiments. Diverse MDRB were detected in most of the aquaculture water samples, and a strain with high-level colistin resistance, named Ralstonia pickettii MCR, was isolated. The risk of horizontal transfer of the colistin resistance of R. pickettii MCR through conjugation and transformation was low, but the colistin resistance could be steadily transmitted to offspring through vertical transfer. The findings have important implications for the future regulation of antibiotic use in aquaculture farms globally to address the growing threat posed by antibiotic resistance to human health.
PubMed: 37935916
DOI: 10.1038/s43705-023-00321-w -
Biology Oct 2023Translation efficiency modulates gene expression in prokaryotes. The comparative analysis of translation elongation efficiency characteristics of genus bacteria genomes...
Translation efficiency modulates gene expression in prokaryotes. The comparative analysis of translation elongation efficiency characteristics of genus bacteria genomes revealed that these characteristics diverge in accordance with the phylogeny of . The first branch of this genus is a group of bacteria commonly found in moist environments such as soil and water that includes the species , , and , which are also described as nosocomial infection pathogens. In contrast, the second branch is plant pathogenic bacteria consisting of , , and . We found that the soil have a significantly lower number and energy of potential secondary structures in mRNA and an increased role of codon usage bias in the optimization of highly expressed genes' translation elongation efficiency, not only compared to phytopathogenic but also to , which is closely related to the genus. The observed alterations in translation elongation efficiency of orthologous genes are also reflected in the difference of potentially highly expressed gene' sets' content among branches with different lifestyles. Analysis of translation elongation efficiency characteristics can be considered a promising approach for studying complex mechanisms that determine the evolution and adaptation of bacteria in various environments.
PubMed: 37887048
DOI: 10.3390/biology12101338 -
Microorganisms Sep 2023The pressing need to safeguard the health of astronauts aboard the International Space Station (ISS) necessitates constant and rigorous microbial monitoring. Recognizing...
The pressing need to safeguard the health of astronauts aboard the International Space Station (ISS) necessitates constant and rigorous microbial monitoring. Recognizing the shortcomings of traditional culture-based methods, NASA is deliberating the incorporation of molecular-based techniques. The challenge, however, lies in developing and validating effective methods for concentrating samples to facilitate this transition. This study is dedicated to investigating the potential of an ISS Smart Sample Concentrator (iSSC) as an innovative concentration method. First, the iSSC system and its components were tested and optimized for microgravity, including various testing environments: a drop tower, parabolic flight, and the ISS itself. Upon confirming the system's compatibility with microgravity, we further evaluated its proficiency and reliability in concentrating large volumes (i.e., 1 L) of water samples inoculated with different microbes. The samples carried 10 to 10 colony-forming units (CFUs) of , , or per liter, aligning with NASA's acceptable limit of 5 × 10 CFU/L. The average retrieved volume post-concentration was ≈450 µL, yielding samples that were ≈2200 times more concentrated for subsequent quantitative PCR (qPCR) and CFU analysis. The average microbial percent recovery, as assessed with CFU counts, demonstrated consistency for and at around 50% and 45%, respectively. For , the efficiency oscillated between 40% and 80%. Interestingly, when we examined microbial recovery using qPCR, the results showed more variability across all tested species. The significance of these findings lies not merely in the successful validation of the iSSC but also in the system's proven consistency, as evidenced by its alignment with previous validation-phase results. In conclusion, conducted research underscored the potential of the iSSC in monitoring microbial contamination in potable water aboard the ISS, heralding a paradigm shift from culture-based to molecular-based monitoring methods.
PubMed: 37764154
DOI: 10.3390/microorganisms11092310