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FEMS Microbiology Ecology Jun 2005This review summarizes the recent advances in understanding the ecophysiological role and structure-function features of methanotrophic bacteria living in various cold... (Review)
Review
This review summarizes the recent advances in understanding the ecophysiological role and structure-function features of methanotrophic bacteria living in various cold ecosystems. The occurrence of methanotrophs in a majority of psychrosphere sites was verified by direct measurement of their methane-utilizing activity, by electron microscopy and immunofluorescent observations, and analyses of specific signatures in cellular phospholipids and total DNAs extracted from environmental samples. Surprisingly, the phenotypic and genotypic markers of virtually all extant methanotrophs were detected in various cold habitats, such as underground waters, Northern taiga and tundra soils, polar lakes and permafrost sediments. Also, recent findings indicated that even after long-term storage in permafrost, some methanotrophs can oxidize and assimilate methane not only at positive but also at subzero temperatures. Pure cultures of psychrophilic and psychrotolerant methanotrophs were isolated and characterized as new genera and species: Methylobacter psychrophilus, Methylosphaera hansonii, Methylocella palustris, Methylocella silvestris, Methylocella tundrae, Methylocapsa acidiphila and Methylomonas scandinavica. However, our knowledge about their adaptive mechanisms and survival in cold ecosystems remains limited and needs to be established using both traditional and molecular microbiological methods.
Topics: Adaptation, Biological; Cold Temperature; Ecology; Ecosystem; Geography; Methane; Methylobacteriaceae; Phylogeny; Proteobacteria
PubMed: 16329925
DOI: 10.1016/j.femsec.2005.02.010 -
Journal of Pediatric Hematology/oncology Jul 2020Roseomonas gilardii is a Gram-negative coccobacillus identified in immunocompromised pediatric patients. A 5-year-old male with a history of HbSβ thalassemia status... (Review)
Review
Roseomonas gilardii is a Gram-negative coccobacillus identified in immunocompromised pediatric patients. A 5-year-old male with a history of HbSβ thalassemia status postsurgical splenectomy presented to the emergency department with fever. Blood cultures grew R. gilardii at 63 hours, but the patient had been discharged home at 48 hours. The patient was readmitted for repeat cultures and initiated on meropenem for 10 days as Roseomonas spp. are often resistant to third generation cephalosporins. R. gilardii is a rare cause of bacteremia in immunocompromised patients. Clinicians should consider Roseomonas in slow growing Gram-negative rod bacteremias, and consider meropenem as empiric coverage.
Topics: Bacteremia; Child, Preschool; Gram-Negative Bacterial Infections; Humans; Male; Methylobacteriaceae; Prognosis; Thalassemia
PubMed: 30951022
DOI: 10.1097/MPH.0000000000001476 -
International Journal of Microbiology 2022Hydrocarbon-derived pollutants are becoming one of the most concerning ecological issues. Thus, there is a need to investigate and develop innovative, low-cost,...
Hydrocarbon-derived pollutants are becoming one of the most concerning ecological issues. Thus, there is a need to investigate and develop innovative, low-cost, eco-friendly, and fast techniques to reduce and/or eliminate pollutants using biological agents. The study was conducted to isolate, characterize, and identify potential diesel-degrading bacteria. Samples were collected from flower farms, lakeshores, old aged garages, asphalt, and bitumen soils and spread on selective medium (Bushnell Haas mineral salt agar) containing diesel as the growth substrate. The isolates were characterized based on their growth patterns using optical density measurement, biochemical tests, and gravimetric analysis and identified using the Biolog database and 16S rRNA gene sequencing techniques. Subsequently, six diesel degraders were identified and belong to , , , , , and . Among these, based on gravimetric analysis, the three potent isolates AAUW23, AAUG11, and AAUG36 achieved 84%, 83.4%, and 83% diesel degradation efficiency, respectively, in 15 days. Consequently, the partial 16S rRNA gene sequences revealed that the two most potent bacterial strains (AAUW23 and AAUG11) were , while AAUG36 was . This study demonstrated that bacterial species isolated from hydrocarbon-contaminated and/or uncontaminated environments could be optimized to be used as potential bioremediation agents for diesel removal.
PubMed: 35096070
DOI: 10.1155/2022/5655767 -
BMC Infectious Diseases Feb 2019Roseomonas mucosa, as a Gram-negative coccobacilli, is an opportunistic pathogen that has rarely been reported in human infections. Here we describe a case of bacteremia... (Review)
Review
BACKGROUND
Roseomonas mucosa, as a Gram-negative coccobacilli, is an opportunistic pathogen that has rarely been reported in human infections. Here we describe a case of bacteremia in an infective endocarditis patient with systemic lupus erythematosus (SLE).
CASE PRESENTATIONS
A 44-year-old female patient with SLE suffered bacteremia caused by Roseomonas mucosa complicated with infective endocarditis (IE). The patient started on treatment with piperacillin-tazobactam and levofloxacin against Roseomonas mucosa, which was switched after 4 days to meropenem and amikacin for an additional 2 weeks. She had a favorable outcome with a 6-week course of intravenous antibiotic therapy.
DISCUSSION AND CONCLUSIONS
Roseomonas mucosa is rarely reported in IE patients; therefore, we report the case in order to improve our ability to identify this pathogen and expand the range of known bacterial causes of infective endocarditis.
Topics: Adult; Amikacin; Anti-Bacterial Agents; Bacteremia; Endocarditis; Endocarditis, Bacterial; Female; Gram-Negative Bacterial Infections; Humans; Levofloxacin; Lupus Erythematosus, Systemic; Methylobacteriaceae; Piperacillin, Tazobactam Drug Combination
PubMed: 30755159
DOI: 10.1186/s12879-019-3774-0 -
International Journal of Systematic and... Oct 2021A novel species of the genus , designated SYSU M41301, was isolated from water sample of the Pearl River estuary in Guangdong, China. Polyphasic, taxonomic and...
A novel species of the genus , designated SYSU M41301, was isolated from water sample of the Pearl River estuary in Guangdong, China. Polyphasic, taxonomic and phylogenomic analyses were used to determine the taxonomy position of the strain. Phylogenetic analysis using 16S rRNA gene sequence indicated that strain SYSU M41301 showed the highest sequence similarity to KCTC 22213 (97.9 %) and KCTC 23339 (96.4 %). The novel species could be differentiated from other species of the genus by its distinct phenotypic and genotypic characteristics. The isolate was Gram-staining-negative, aerobic, short rod-shape, oxidase-positive and non-motile. The predominant respiratory quinone was ubiquinone 8 (Q-8). The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, and one unidentified polar lipid. The major fatty acids (>10 % of total) were 11-methyl C 7, summed feature 3 (C c / or C c) and summed feature 8 (C 7 and/or C 6). The G+C content of the novel isolate based on genomic DNA was 72.0 mol%. On the basis of phenotypic, genotypic and phylogenetic data, strain SYSU M41301 should be considered to represent a novel species in the genus for which the name sp. nov. is proposed with the type strain SYSU M41301 (=KCTC 72726=CGMCC 1.18613).
Topics: Bacterial Typing Techniques; Base Composition; China; DNA, Bacterial; Estuaries; Fatty Acids; Methylobacteriaceae; Phospholipids; Phylogeny; RNA, Ribosomal, 16S; Rivers; Sequence Analysis, DNA; Ubiquinone
PubMed: 34623235
DOI: 10.1099/ijsem.0.004994 -
Antibiotics (Basel, Switzerland) Sep 2021The discharge of untreated hospital and domestic wastewater into receiving water bodies is still a prevalent practice in developing countries. Unfortunately, because of...
The discharge of untreated hospital and domestic wastewater into receiving water bodies is still a prevalent practice in developing countries. Unfortunately, because of an ever-increasing population of people who are perennially under medication, these wastewaters contain residues of antibiotics and other antimicrobials as well as microbial shedding, the direct and indirect effects of which include the dissemination of antibiotic resistance genes and an increase in the evolution of antibiotic-resistant bacteria that pose a threat to public and environmental health. This study assessed the taxonomic and functional profiles of bacterial communities, as well as the antibiotic concentrations in untreated domestic wastewater (DWW) and hospital wastewater (HWW), using high-throughput sequencing analysis and solid-phase extraction coupled to Ultra-high-performance liquid chromatography Mass Spectrometry (UHPLC-MS/MS) analysis, respectively. The physicochemical qualities of both wastewater systems were also determined. The mean concentration of antibiotics and the concentrations of Cl, F and PO were higher in HWW samples than in DWW samples. The phylum was dominant in DWW with a sequence coverage of 59.61% while was dominant in HWW samples with a sequence coverage of 86.32%. At genus level, the genus (20.65%) and (67.41%) were predominant in DWW and HWW samples, respectively. Several pathogenic or opportunistic bacterial genera were detected in HWW ( and ) and DWW (, and ) samples. Functional prediction analysis indicated the presence of beta-lactam resistance, cationic antimicrobial peptide (CAMP) resistance and vancomycin resistance genes in HWW samples. The presence of these antibiotic resistance genes and cassettes were positively correlated with the presence of pathogens. These findings show the risk posed to public and environmental health by the discharge of untreated domestic and hospital wastewaters into environmental water bodies.
PubMed: 34572642
DOI: 10.3390/antibiotics10091059 -
Microbial Genomics Sep 2023comprises a diverse group of bacteria with various lifestyles. Although best known for their nodule-based nitrogen-fixation in symbiosis with legumes, a select group of...
comprises a diverse group of bacteria with various lifestyles. Although best known for their nodule-based nitrogen-fixation in symbiosis with legumes, a select group of bradyrhizobia are also capable of photosynthesis. This ability seems to be rare among rhizobia, and its origin and evolution in these bacteria remain a subject of substantial debate. Therefore, our aim here was to investigate the distribution and evolution of photosynthesis in using comparative genomics and representative genomes from closely related taxa in the families and . We identified photosynthesis gene clusters (PGCs) in 25 genomes belonging to three different lineages, notably the so-called Photosynthetic, and supergroups. Also, two different PGC architectures were observed. One of these, PGC1, was present in genomes from the Photosynthetic supergroup and in three genomes from a species in the supergroup. The second cluster, PGC2, was also present in some strains from the supergroup, as well as in those from the supergroup. PGC2 was largely syntenic to the cluster found in and . Bayesian ancestral state reconstruction unambiguously showed that the ancestor of lacked a PGC and that it was acquired horizontally by various lineages. Maximum-likelihood phylogenetic analyses of individual photosynthesis genes also suggested multiple acquisitions through horizontal gene transfer, followed by vertical inheritance and gene losses within the different lineages. Overall, our findings add to the existing body of knowledge on ’s evolution and provide a meaningful basis from which to explore how these PGCs and the photosynthesis itself impact the physiology and ecology of these bacteria.
Topics: Bradyrhizobium; Photosynthesis
PubMed: 37676703
DOI: 10.1099/mgen.0.001105 -
Journal of Clinical Microbiology May 2014Methylobacterium species are a cause of health care-associated infection, including infections in immunocompromised hosts. The ability of Methylobacterium species to... (Review)
Review
Methylobacterium species are a cause of health care-associated infection, including infections in immunocompromised hosts. The ability of Methylobacterium species to form biofilms and to develop resistance to high temperatures, drying, and disinfecting agents may explain the colonization of Methylobacterium in the hospital environment in, e.g., endoscopes. Due to its slow growth, it can be easily missed during microbiological surveillance of endoscope reprocessing. The purpose of this minireview is to present an overview of documented infections and cross-contaminations with Methylobacterium related to endoscopic procedures and to illustrate the health care-associated relevance of this slow-growing bacterium.
Topics: Cross Infection; Delivery of Health Care; Endoscopy; Equipment Contamination; Gram-Negative Bacterial Infections; Methylobacterium
PubMed: 24430456
DOI: 10.1128/JCM.03561-13 -
Systematic and Applied Microbiology May 2021Two Gram-negative, aerobic, rod-shaped and yellow-orange pigmented bacterial strains (LMG 31523 and LMG 31524) were isolated from roots of wild-growing Alkanna tinctoria...
Two Gram-negative, aerobic, rod-shaped and yellow-orange pigmented bacterial strains (LMG 31523 and LMG 31524) were isolated from roots of wild-growing Alkanna tinctoria plants collected near Thessaloniki, Greece. Analysis of their 16S rRNA gene sequences revealed that they form a separate cluster related to the genus Roseomonas. A comparative whole genome analysis of the two strains and the type strains of related Roseomonas species revealed average nucleotide identity values from 78.84 and 80.32%. The G + C contents of the genomic DNA of strains LMG 31523 and LMG 31524 were 69.69% and 69.74%, respectively. Combined data from phenotypic, phylogenetic and chemotaxonomic studies indicated that the strains LMG 31523 and LMG 31524 represent a novel species of the genus Roseomonas. Genome analysis of the new strains showed a number of genes involved in survival in the rhizosphere environment and in plant colonization and confirmed the endophytic characteristics of LMG 31523 and LMG 31524. Since the strains LMG 31523 and LMG 31524 were isolated from a plant collected in Greece the name Roseomonas hellenica sp. nov. is proposed. The type strain is LMG 31523 (=CECT 30032).
Topics: Bacterial Typing Techniques; Base Composition; Boraginaceae; DNA, Bacterial; Endophytes; Greece; Methylobacteriaceae; Phylogeny; Pigmentation; Plant Roots; RNA, Ribosomal, 16S; Sequence Analysis, DNA
PubMed: 33945925
DOI: 10.1016/j.syapm.2021.126206 -
Dental and Medical Problems 2022Wearing masks has become an essential safety measure during the coronavirus 2019 (COVID-19) pandemic. Especially clinicians in dental clinics should focus on infection...
BACKGROUND
Wearing masks has become an essential safety measure during the coronavirus 2019 (COVID-19) pandemic. Especially clinicians in dental clinics should focus on infection control. However, there is currently no data regarding the frequency of replacement of the masks used in hospitals. Hence, it is necessary for dental clinic staff, who deal with many patients in an aerosol-producing environment, to have precise mask-wearing guidelines.
OBJECTIVES
The aim of this study was to evaluate the contamination on the inner surface of the masks used by clinicians in dental clinics and provide basic data to describe hospital infection control guidelines in greater detail.
MATERIAL AND METHODS
For Study I,12 participants were recruited. The experiment was conducted indoors. After wearing the mask, the temperature and the humidity inside the mask were measured at the set time points (immediately after wearing the mask, and 10 min, 30 min, 1 h, 2 h, and 4 h after wearing the mask). During the experiment, talking was not allowed. For Study II, 23 clinicians from dental clinics were recruited. After wearing the mask, the temperature, the humidity and the number of colony-forming units (CFU) inside the mask were measured at the set time points. Finally, 15 samples were selected for the study based on a survey. Bacterial identification was conducted using the 16S rDNA sequencing.
RESULTS
The temperature and the humidity inside the mask increased significantly relative to room temperature and room humidity, respectively. Bacteria were found in all the masks worn for more than 10 min and the CFU values increased with the mask-wearing time. Bacteria belonging to the genera Staphylococcus, Bacillus and Roseomonas were detected in the used mask.
CONCLUSIONS
A mask should not be worn for more than 2 h; however, the frequency of mask replacement can vary, depending on the number of patients encountered and the working environment.
Topics: Bacteria; COVID-19; Dental Clinics; Humans; Pandemics
PubMed: 35761755
DOI: 10.17219/dmp/143544