RESUMEN
Tattooing and use of permanent makeup (PMU) have dramatically increased over the last decade, with a concomitant increase in ink-related infections. Studies have shown evidence that commercial tattoo and PMU inks are frequently contaminated with pathogenic microorganisms. Considering that tattoo inks are placed into the dermal layer of the skin where anaerobic bacteria can thrive and cause infections in low-oxygen environments, the prevalence of anaerobic and aerobic bacteria should be assessed in tattoo and PMU inks. In this study, we tested 75 tattoo and PMU inks using the analytical methods described in the FDA Bacteriological Analytical Manual Chapter 23 for the detection of both aerobic and anaerobic bacterial contamination, followed by 16S rRNA gene sequencing for microbial identification. Of 75 ink samples, we found 26 contaminated samples with 34 bacterial isolates taxonomically classified into 14 genera and 22 species. Among the 34 bacterial isolates, 19 were identified as possibly pathogenic bacterial strains. Two species, namely Cutibacterium acnes (four strains) and Staphylococcus epidermidis (two strains) were isolated under anaerobic conditions. Two possibly pathogenic bacterial strains, Staphylococcus saprophyticus and C. acnes, were isolated together from the same ink samples (n = 2), indicating that tattoo and PMU inks can contain both aerobic (S. saprophyticus) and anaerobic bacteria (C. acnes). No significant association was found between sterility claims on the ink label and the absence of bacterial contamination. The results indicate that tattoo and PMU inks can also contain anaerobic bacteria. IMPORTANCE: The rising popularity of tattooing and permanent makeup (PMU) has led to increased reports of ink-related infections. This study is the first to investigate the presence of both aerobic and anaerobic bacteria in commercial tattoo and PMU inks under aerobic and anaerobic conditions. Our findings reveal that unopened and sealed tattoo inks can harbor anaerobic bacteria, known to thrive in low-oxygen environments, such as the dermal layer of the skin, alongside aerobic bacteria. This suggests that contaminated tattoo inks could be a source of infection from both types of bacteria. The results emphasize the importance of monitoring these products for both aerobic and anaerobic bacteria, including possibly pathogenic microorganisms.
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Bacterias Aerobias , Bacterias Anaerobias , Tinta , ARN Ribosómico 16S , Tatuaje , Bacterias Anaerobias/aislamiento & purificación , Bacterias Anaerobias/genética , Bacterias Anaerobias/clasificación , Bacterias Aerobias/aislamiento & purificación , Bacterias Aerobias/clasificación , Bacterias Aerobias/genética , ARN Ribosómico 16S/genéticaRESUMEN
In order to explore the evolution law and driving mechanism of aerobic denitrification bacteria in Baiyangdian Lake under different hydrological scenarios, based on water quality survey and high-throughput sequencing technology, this study conducted a water quality factor analysis and aerobic denitrification bacteria α-diversity analysis, species composition, and network analysis. The results showed that the water body of Baiyangdian Lake was weakly alkaline, with the highest T and the lowest DO in the rainy season and the lowest T and the highest DO in the freezing season. There were significant differences between NH4+-N, NO2--N, NO3--N, TN, permanganate index, Fe, and Mn in Baiyangdian water under different hydrological scenarios (P < 0.01), and there was no significant difference in TP under different hydrological scenarios (P > 0.05). The largest category in water bodies under different hydrological scenarios was Proteobacteria, and the genera with a higher relative abundance were Magnetospirillum, Aeromonas, Pseudomonas, Azospirillum, and Bradyrhizobium. In addition, within the aerobic denitrifying bacteria community, there were significant differences in α-diversity (P < 0.001), with the highest abundance of microbial communities occurring during the freezing period, and the highest diversity and evenness of microbial communities during the dry and freezing periods. According to the RDA and Mantel analyses, the water quality driving factors of flora were different under different hydrological scenarios. The water quality driving factors of flora in the dry season were pH, NO3--N, NO2--N, and permanganate index; the driving factors of flora in the rainy season were pH, T, DO, NO2--N, and TP; the driving factors of flora in the normal season were NO2--N, Fe, and permanganate index; and the driving factors of flora in the freezing season were NO3--N and NONO2--N. Network analysis showed that there were temporal differences in species related to water quality driving factors. The genera related to water quality driving factors during the dry season were Magnetospirillum, Aeromonas, and Azoarcus, whereas the genera related to the rainy season were Magnetospirillum, Pseudomonas, and Aeromonas. The genera related to the normal season were Magnetospirillum, Pseudomonas, and Limnohabitans, and the genera related to the freezing period were Magnetospirillum, Azoarcus, and Pseudomonas. The relationship between key water quality factors (mainly T, DO, NO3--N, and permanganate index) and aerobic denitrification flora in different hydrological scenarios was gradually changing with time. In conclusion, the study on the evolution characteristics of aerobic denitrification bacteria in Baiyangdian Lake under different hydrological scenarios and the driving mechanism of environmental factors could provide a basis for understanding the evolution mechanism of aerobic denitrification bacteria in the natural environment.
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Desnitrificación , Lagos , Calidad del Agua , China , Lagos/microbiología , Hidrología , Bacterias Aerobias/metabolismo , Bacterias Aerobias/aislamiento & purificación , Monitoreo del Ambiente , Proteobacteria/aislamiento & purificación , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/metabolismoRESUMEN
Grapsoid crabs (Decapoda: Grapsoidea) inhabiting along the land-sea transition provided various amounts and quality of vascular plant carbon (e.g., fresh mangrove leaf, leaf litter, and mangrove-derived organic carbon) and perform differing levels of herbivory. Other than endogenous cellulase, symbiotic cellulolytic bacteria could also contribute to the crabs' vascular plant carbon assimilation and mineralization. In this study, we isolated culturable cellulolytic bacteria from three gut regions (i.e., stomach, midgut, and hindgut) of 15 species of grapsoid crabs that inhabit in various coastal habitats (i.e., land margin, mangrove forest, tidal flat, and subtidal area). Bacillus, which was isolated from 11 out of the 15 grapsoid crabs, was the most common genus of culturable prominently cellulolytic bacteria among the target species. Seventy to ninety nine percent of culturable cellulolytic bacteria were removed, and the endoglucanase activity of five species was significantly reduced by 14.4-27.7% after antibiotic treatment. These results suggest that cellulolytic bacteria play a role in assisting mangrove carbon utilization in coastal grapsoid crabs, especially those inhabiting mangrove, mudflat, and subtidal areas. The significantly higher abundance of cellulolytic bacteria and the generally higher hydrolytic capacity of the bacteria in mangrove crab species suggest that they receive more contribution from symbionts for mangrove carbon utilization, while semi-terrestrial crabs seem to depend little on symbiotic cellulase due to the lower abundances.
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Celulosa , Microbioma Gastrointestinal , Humedales , Animales , Celulosa/metabolismo , Braquiuros/microbiología , Bacterias Aerobias/metabolismo , Bacterias Aerobias/fisiología , Celulasa/metabolismo , Simbiosis , Tracto Gastrointestinal/microbiología , Carbono/metabolismoRESUMEN
Aerobic anoxygenic phototrophic (AAP) bacteria are an important component of freshwater bacterioplankton. They can support their heterotrophic metabolism with energy from light, enhancing their growth efficiency. Based on results from cultures, it was hypothesized that photoheterotrophy provides an advantage under carbon limitation and facilitates access to recalcitrant or low-energy carbon sources. However, verification of these hypotheses for natural AAP communities has been lacking. Here, we conducted whole community manipulation experiments and compared the growth of AAP bacteria under carbon limited and with recalcitrant or low-energy carbon sources under dark and light (near-infrared light, λ > 800 nm) conditions to elucidate how they profit from photoheterotrophy. We found that AAP bacteria induce photoheterotrophic metabolism under carbon limitation, but they overcompete heterotrophic bacteria when carbon is available. This effect seems to be driven by physiological responses rather than changes at the community level. Interestingly, recalcitrant (lignin) or low-energy (acetate) carbon sources inhibited the growth of AAP bacteria, especially in light. This unexpected observation may have ecosystem-level consequences as lake browning continues. In general, our findings contribute to the understanding of the dynamics of AAP bacteria in pelagic environments.
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Carbono , Procesos Fototróficos , Carbono/metabolismo , Procesos Heterotróficos , Lagos/microbiología , Bacterias Aerobias/metabolismo , Bacterias Aerobias/crecimiento & desarrollo , Luz , Ecosistema , Bacterias/metabolismo , Bacterias/crecimiento & desarrollo , Bacterias/genéticaRESUMEN
Aerobic spore-forming (ASF) bacteria have been reported to cause ropiness in bread. Sticky and stringy degradation, discoloration, and an odor reminiscent of rotting fruit are typical characteristics of ropy bread spoilage. In addition to economic losses, ropy bread spoilage may lead to health risks, as virulent strains of ASF bacteria are not uncommon. However, the lack of systematic approaches to quantify physicochemical spoilage characteristics makes it extremely difficult to assess rope formation in bread. To address this problem, the aim of this study was to identify, characterize and objectively assess the spoilage potential of ASF bacteria associated with ropy bread. Hence, a set of 82 ASF bacteria, including isolates from raw materials and bakery environments as well as strains from international culture collections, were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and their species identity confirmed by 16S rRNA and gyrA or panC gene sequencing. A standardized approach supported by objective colorimetric measurements was developed to assess the rope-inducing potential (RIP) of a strain by inoculating autoclaved bread slices with bacterial spores. In addition, the presence of potential virulence factors such as swarming motility or hemolysis was investigated. This study adds B. velezensis, B. inaquosorum and B. spizizenii to the species potentially implicated of causing ropy bread spoilage. Most importantly, this study introduces a standardized classification protocol for assessing the RIP of a bacterial strain. Colorimetric measurements are used to objectively quantify the degree of breadcrumb discoloration. Furthermore, our results indicate that strains capable of inducing rope spoilage in bread often exhibit swarming motility and virulence factors such as hemolysis, raising important food quality considerations.
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Pan , Microbiología de Alimentos , Pan/microbiología , Esporas Bacterianas/crecimiento & desarrollo , Bacterias Aerobias/aislamiento & purificación , Bacterias Aerobias/clasificación , Bacterias Aerobias/genética , Bacterias Aerobias/crecimiento & desarrollo , ARN Ribosómico 16S/genética , Factores de Virulencia/genética , Contaminación de Alimentos/análisis , Espectrometría de Masa por Láser de Matriz Asistida de Ionización DesorciónRESUMEN
Urinary tract infections are a common diagnosis in dogs presenting to veterinary practice. Veterinarians often treat suspected infections empirically, either in the absence of culture and susceptibility testing results or whilst waiting for them. This study aimed to identify the bacteria most frequently isolated from canine urinary samples and their antimicrobial susceptibility patterns in South East Queensland (SEQ) to help guide responsible empirical antimicrobial prescription by the veterinary community in this geographical location. Cumulative antibiograms were generated from the results of 1284 culture-positive urinary samples in SEQ, obtained from a commercial veterinary laboratory over a 5-year period. Escherichia coli was the most commonly isolated bacterial species (43%), followed by Staphylococcus spp. (23%), Proteus spp. (21%) and Enterococcus spp. (10%). Of the six most common isolates, 97% had susceptibility to at least one low-importance antimicrobial. Susceptibility to the low-importance and first-line antimicrobial recommendation, amoxicillin, was 81% for E. coli and 24% for Staphylococcus spp. Susceptibility of both E. coli and Staphylococcus spp. to medium-importance and commonly recommended empirical antimicrobials, trimethoprim sulphonamides and amoxicillin-clavulanic acid was ≥85% and >92% for high-importance antimicrobials enrofloxacin and ceftiofur. Of the E. coli and Staphylococcus spp. isolates, 8.8% and 4%, respectively, were considered multidrug resistant. There was no increase in resistance to antimicrobials detected over the study period. Susceptibilities suggest low- and medium-importance antimicrobials remain acceptable first-line empirical treatments. However, this should be continually assessed and updated using local surveillance data.
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Antibacterianos , Bacterias Aerobias , Enfermedades de los Perros , Pruebas de Sensibilidad Microbiana , Infecciones Urinarias , Animales , Perros , Queensland/epidemiología , Enfermedades de los Perros/microbiología , Enfermedades de los Perros/orina , Enfermedades de los Perros/tratamiento farmacológico , Antibacterianos/farmacología , Pruebas de Sensibilidad Microbiana/veterinaria , Infecciones Urinarias/veterinaria , Infecciones Urinarias/microbiología , Infecciones Urinarias/tratamiento farmacológico , Infecciones Urinarias/orina , Bacterias Aerobias/efectos de los fármacos , Bacterias Aerobias/aislamiento & purificación , Farmacorresistencia BacterianaRESUMEN
BACKGROUND: Hospitals are exposed to abundant contamination sources with limited remediation strategies. Without new countermeasures or treatments, the risk of health care-associated infections will remain high. This study explored the impact of advanced photohydrolysis continuous disinfection technology on hospital environmental bioburden. METHODS: Two acute care intensive care units in different locations (ie, Kentucky, Louisiana) during different time periods were sampled every 4 weeks for 4 months for colony-forming units (CFUs) of methicillin-resistant Staphylococcus aureus (MRSA) and fungi on surfaces and floors and fungi and aerobic bacteria in the air. RESULTS: At both sites, surface testing showed greater than 98% reduction in mean fungi and MRSA CFUs. Floor results had reductions by more than 96% for fungi and MRSA at both sites. Aerobic bacterial air and fungal CFUs had reductions up to 72% and 89%, respectively. HAIs declined 70% when postactivation data were compared to preactivation data. DISCUSSION: The continuous nature of advanced photohydrolysis decontamination, its ability to be used in occupied rooms, and its independence of human resources provide an innovative intervention for complex health care environments. CONCLUSIONS: This study is on the pioneering edge of demonstrating that continuous decontamination can reduce surface, floor, and air contamination and thereby reduce the acquisition of HAIs.
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Infección Hospitalaria , Desinfectantes , Desinfección , Hongos , Unidades de Cuidados Intensivos , Staphylococcus aureus Resistente a Meticilina , Staphylococcus aureus Resistente a Meticilina/efectos de la radiación , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Humanos , Desinfectantes/farmacología , Hongos/efectos de la radiación , Desinfección/métodos , Infección Hospitalaria/prevención & control , Infección Hospitalaria/microbiología , Microbiología Ambiental , Bacterias Aerobias/efectos de la radiación , Bacterias Aerobias/efectos de los fármacos , Recuento de Colonia Microbiana , Microbiología del AireRESUMEN
Reproductive tract infections (RTIs) are a persistent public health threat worldwide, particularly among women in low-income countries of Africa, including Ethiopia, where drug resistance is also a growing problem. It is crucial to address this problem to ensure women's health and well-being. A cross-sectional study was carried out among a cohort of 398 women of reproductive age who sought medical attention at the Gynecology Department of the Arba Minch General Hospital, southern Ethiopia, from January to June 2020. They were chosen through systematic random sampling, and a pre-tested structured questionnaire was used to collect the data. The collection of vaginal and/or cervical swabs were done to diagnose bacterial vaginosis (BV) and aerobic vaginitis (AV) using Nugent and AV score analyses, respectively. The swabs were subjected to standard microbiological culture techniques to detect the isolates causing AV and vaginal candidiasis (VC). The susceptibility profiles of the causative agents of AV were checked by the Kirby-Bauer disc diffusion technique. Descriptive and inferential statistical analyses were also done. Aerobic vaginitis was the predominantly diagnosed RTI (n = 122, 30.7%), followed by BV (n = 117, 29.4%) and VC (n = 111, 27.9%). The prominent bacteria of AV were Escherichia coli (n = 36, 34.2%) and Klebsiella pneumoniae (n = 30, 28.5%). The overall rate of multidrug-resistant (MDR) bacteria was 65.71% (n = 69). History of abortion (p = 0.01; AOR = 4.0, 95% CI = 2.1, 7.7) and the habit of using vaginal pH-altering contraceptives (p = 0.01; AOR = 4.7, 95% CI = 2.5, 8.8) have the greatest odds of RTI. The high prevalence of RTIs in our study warrants an urgent intervention to minimize the associated morbidities and complications. The overall rate of MDR bacterial isolates necessitates the implementation of an effective surveillance program in the study setting.
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Candidiasis Vulvovaginal , Vaginosis Bacteriana , Humanos , Femenino , Etiopía/epidemiología , Vaginosis Bacteriana/epidemiología , Vaginosis Bacteriana/microbiología , Adulto , Candidiasis Vulvovaginal/epidemiología , Candidiasis Vulvovaginal/microbiología , Estudios Transversales , Adulto Joven , Adolescente , Vagina/microbiología , Persona de Mediana Edad , Vaginitis/microbiología , Vaginitis/epidemiología , Antibacterianos/uso terapéutico , Antibacterianos/farmacología , Bacterias Aerobias/aislamiento & purificación , PrevalenciaRESUMEN
Heterotrophic bacteria are commonly found in water samples. While these Heterotrophic Bacterial/Plate Counts (HPC) do not necessarily indicate a health hazard, high counts provide a good indication of the efficiency of water disinfection and integrity of distribution systems. The aim of this study was to compare the PetrifimTM AC method to the pour plate technique for the testing of HPC in water samples. Artificially contaminated (192 samples) and natural water samples (25) were processed using two methods. Both methods accurately detected high, medium and low counts of HPC, producing average Z scores between -2 and +2. Paired-wise student t-test and correlation coefficient showed nonsignificant differences between the results of two methods. Acceptable repeatability and reproducibility was obtained using both the methods. Uncertainty of measurement for PetrifilmTM AC and pour plate method was found to be 2.9% and 5.4%, respectively. PetrifilmTM AC proved to be robust at 33°C and 37°C. In conclusion, PetrifimTM AC, which is easy to process, read, and less time consuming, proved to be comparable to the conventional pour plate method in establishing HPC in water. In addition, PetrifimTM AC requires less space for the processing and incubation, generate small volume of waste for disposal, and requires no equipment, except for the incubator.
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Carga Bacteriana , Microbiología del Agua , Carga Bacteriana/métodos , Bacterias Aerobias/aislamiento & purificación , Reproducibilidad de los Resultados , Recuento de Colonia Microbiana/métodos , Procesos HeterotróficosRESUMEN
Aerobic anoxygenic phototrophic bacteria (AAPB) are significant bacterial groups in aquatic ecosystems, known for their rapid growth and photoheterotrophic characteristics. However, the distribution and ecological assembly process of AAPB in low irradiation freshwater basins remain unclear, warranting further investigation. In this study, we present the diversity, abundance, spatial variations, ecological process, and community interaction of AAPB in sediment of Three Gorges Reservoir (TGR) under low irradiation. Our findings demonstrate the dominant genera of AAPB community that exist in the TGR area also are appeared in different waters, with some regional preference. Moreover, the concentration of pufM gene, an indicator for AAPB, maintains a consistently high numerical level ranging from (2.21 ± 0.44) × 104 to (9.98 ± 0.30) × 107 gene copies/g. Although solar irradiation is suggested as the major factor affecting AAPB, it remains unclear whether and how AAPB differ between regions due to varying solar irradiation levels. Our results show spatial differences between total bacteria and AAPB communities, with significant differences observed only in AAPB. Geographical and environmental factor contributed less than 10% to the spatial difference of community, with sediment type and environmental factors being the key factors influencing microbial community structure. The stochastic process plays a dominant role in the aggregation and replacement of AAPB communities, among which the most contribution is dispersal limitation. For AAPB network, Yoonia and Gemmobacter are the hubs for modules. Those results valuable insights into the AAPB communities in TGR with low irradiation.
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Procesos Fototróficos , China , Bacterias Aerobias , Biodiversidad , Sedimentos Geológicos/microbiología , Ecosistema , Bacterias/clasificación , Monitoreo del AmbienteRESUMEN
OBJECTIVES: Eravacycline, a new tetracycline derivative, exhibits broad-spectrum antimicrobial susceptibility. This study aimed to comprehensively investigate in vitro activities of eravacycline, tigecycline, and ertapenem against various Gram-positive, Gram-negative, and anaerobic bacteria. METHODS: Minimum inhibitory concentrations (MICs) were determined using the broth microdilution method. The following bacterial species were collected: vancomycin-sensitive (VS) Enterococci species, vancomycin-resistant Enterococci species (VRE), Staphylococcus aureus, Streptococcus anginosus, Bacteroides species, Clostridioides difficile, Clostridium innocuum, Clostridium perfringens, Parabacteroides distasonis, and Stenotrophomonas maltophilia. RESULTS: We found that eravacycline exhibited superior in vitro activity compared to tigecycline and ertapenem. Notably, it exhibited the lowest MIC90 for several bacterial species, including VS E. faecalis (0.12 µg/mL), VS E. faecium (0.12 µg/mL), and others. Besides, VRE was susceptible to eravacycline (MIC90:0.12 µg/mL) and tigecycline (MIC90:0.12 µg/mL), but was all resistant to ertapenem (MIC90 > 64 µg/mL). S. aureus was also susceptible to eravacycline (MIC90:0.5 µg/mL) as well as tigecycline (MIC90:1.0 µg/mL). Furthermore, S. anginosus showed higher susceptibility to eravacycline (MIC90:2.0 µg/mL) and tigecycline (MIC90:4.0 µg/mL), but lower to ertapenem (MIC90:32.0 µg/mL). Eravacycline and tigecycline also demonstrated good susceptibility to anaerobes, including Bacteroides species (susceptibility rate: 100%), P. distasonis (100%), C. difficile (94.1â100%), C. innocuum (94.1â96.1%), and C. perfringens (88.9â96.3%). For S. maltophilia, both tigecycline and eravacycline showed an MIC90 of 2 µg/mL. A moderate-to-strong correlation (rho = 0.608-0.804, P < 0.001) was noted between the MIC values of eravacycline and tigecycline against various bacterial species. CONCLUSIONS: Our study highlights the potential of eravacycline as an effective treatment option for multidrug-resistant bacterial infections.
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Antibacterianos , Bacterias Anaerobias , Pruebas de Sensibilidad Microbiana , Tetraciclinas , Tigeciclina , Tigeciclina/farmacología , Tetraciclinas/farmacología , Humanos , Antibacterianos/farmacología , Bacterias Anaerobias/efectos de los fármacos , Taiwán , Ertapenem/farmacología , Staphylococcus aureus/efectos de los fármacos , Bacterias Aerobias/efectos de los fármacos , Bacterias Aerobias/aislamiento & purificación , Enterococos Resistentes a la Vancomicina/efectos de los fármacos , Streptococcus anginosus/efectos de los fármacos , Streptococcus anginosus/aislamiento & purificación , Clostridioides difficile/efectos de los fármacos , Stenotrophomonas maltophilia/efectos de los fármacos , Vancomicina/farmacología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacosRESUMEN
BACKGROUND: Aerobic anoxygenic phototrophic (AAP) bacteria are heterotrophic bacteria that supply their metabolism with light energy harvested by bacteriochlorophyll-a-containing reaction centers. Despite their substantial contribution to bacterial biomass, microbial food webs, and carbon cycle, their phenology in freshwater lakes remains unknown. Hence, we investigated seasonal variations of AAP abundance and community composition biweekly across 3 years in a temperate, meso-oligotrophic freshwater lake. RESULTS: AAP bacteria displayed a clear seasonal trend with a spring maximum following the bloom of phytoplankton and a secondary maximum in autumn. As the AAP bacteria represent a highly diverse assemblage of species, we followed their seasonal succession using the amplicon sequencing of the pufM marker gene. To enhance the accuracy of the taxonomic assignment, we developed new pufM primers that generate longer amplicons and compiled the currently largest database of pufM genes, comprising 3633 reference sequences spanning all phyla known to contain AAP species. With this novel resource, we demonstrated that the majority of the species appeared during specific phases of the seasonal cycle, with less than 2% of AAP species detected during the whole year. AAP community presented an indigenous freshwater nature characterized by high resilience and heterogenic adaptations to varying conditions of the freshwater environment. CONCLUSIONS: Our findings highlight the substantial contribution of AAP bacteria to the carbon flow and ecological dynamics of lakes and unveil a recurrent and dynamic seasonal succession of the AAP community. By integrating this information with the indicator of primary production (Chlorophyll-a) and existing ecological models, we show that AAP bacteria play a pivotal role in the recycling of dissolved organic matter released during spring phytoplankton bloom. We suggest a potential role of AAP bacteria within the context of the PEG model and their consideration in further ecological models.
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Lagos , Procesos Fototróficos , Lagos/microbiología , Bacterias/genética , Biomasa , Bacterias Aerobias/genética , Bacterias Aerobias/metabolismo , Fitoplancton/genéticaRESUMEN
The baijiu fermentation environment hosts a variety of micro-organisms, some of which still remain uncultured and uncharacterized. In this study, the isolation, cultivation and characterization of three novel aerobic bacterial strains are described. The cells of strain REN20T were Gram-negative, strictly aerobic, motile and grew at 26-37â°C, at pH 6.0-9.0 and in the presence of 0-5.0âââ% (w/v) NaCl. The cells of strain REN29T were Gram-negative, strictly aerobic, motile and grew at 15-30â°C, at pH 6.0-9.0 and in the presence of 0-10.0âââ% (w/v) NaCl. The cells of strain REN33T were Gram-positive, strictly aerobic, motile and grew at 15-37â°C, at pH 5.0-10.0 and in the presence of 0-7.0âââ% (w/v) NaCl. The digital DNA-DNA hybridization and average nucleotide identity by orthology values between type strains in related genera and REN20T (20.3-36.8â% and 79.8-89.9ââ%), REN29T (20.3-36.8ââ% and 74.5-88.5ââ%) and REN33T (22.6-48.6ââ% and 75.8-84.2ââ%) were below the standard cut-off criteria for the delineation of bacterial species, respectively. Based on polyphasic taxonomy analysis, we propose three new species, Bosea beijingensis sp. nov. (=REN20T=GDMCC 1.2894T=JCM 35118T), Telluria beijingensis sp. nov. (=REN29T=GDMCC 1.2896T=JCM 35119T) and Agrococcus beijingensis sp. nov. (=REN33T=GDMCC 1.2898T=JCM 35164T), which were recovered during cultivation and isolation from baijiu mash.
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Actinomycetales , Bradyrhizobiaceae , Oxalobacteraceae , Cloruro de Sodio , Filogenia , Análisis de Secuencia de ADN , ARN Ribosómico 16S/genética , ADN Bacteriano/genética , Técnicas de Tipificación Bacteriana , Composición de Base , Ácidos Grasos/química , Bacterias AerobiasRESUMEN
Aerobic anoxygenic phototrophic (AAP) bacteria harvest light energy using bacteriochlorophyll-containing reaction centers to supplement their mostly heterotrophic metabolism. While their abundance and growth have been intensively studied in coastal environments, much less is known about their activity in oligotrophic open ocean regions. Therefore, we combined in situ sampling in the North Pacific Subtropical Gyre, north of O'ahu island, Hawaii, with two manipulation experiments. Infra-red epifluorescence microscopy documented that AAP bacteria represented approximately 2% of total bacteria in the euphotic zone with the maximum abundance in the upper 50 m. They conducted active photosynthetic electron transport with maximum rates up to 50 electrons per reaction center per second. The in situ decline of bacteriochlorophyll concentration over the daylight period, an estimate of loss rates due to predation, indicated that the AAP bacteria in the upper 50 m of the water column turned over at rates of 0.75-0.90 d-1. This corresponded well with the specific growth rate determined in dilution experiments where AAP bacteria grew at a rate 1.05 ± 0.09 d-1. An amendment of inorganic nitrogen to obtain N:P = 32 resulted in a more than 10 times increase in AAP abundance over 6 days. The presented data document that AAP bacteria are an active part of the bacterioplankton community in the oligotrophic North Pacific Subtropical Gyre and that their growth was mostly controlled by nitrogen availability and grazing pressure.IMPORTANCEMarine bacteria represent a complex assembly of species with different physiology, metabolism, and substrate preferences. We focus on a specific functional group of marine bacteria called aerobic anoxygenic phototrophs. These photoheterotrophic organisms require organic carbon substrates for growth, but they can also supplement their metabolic needs with light energy captured by bacteriochlorophyll. These bacteria have been intensively studied in coastal regions, but rather less is known about their distribution, growth, and mortality in the oligotrophic open ocean. Therefore, we conducted a suite of measurements in the North Pacific Subtropical Gyre to determine the distribution of these organisms in the water column and their growth and mortality rates. A nutrient amendment experiment showed that aerobic anoxygenic phototrophs were limited by inorganic nitrogen. Despite this, they grew more rapidly than average heterotrophic bacteria, but their growth was balanced by intense grazing pressure.
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Bacterioclorofilas , Procesos Fototróficos , Bacterioclorofilas/metabolismo , Bacterias Aerobias , Agua/metabolismo , Nitrógeno/metabolismo , Agua de Mar/microbiologíaRESUMEN
The nitrogen removal characteristics and microbial response of biochar-immobilized mixed aerobic denitrifying bacteria (BIADB) were investigated at 25 °C and 10 °C. BIADB removed 53.51 ± 1.72 % (25 °C) and 39.90 ± 4.28 % (10 °C) nitrate in synthetic oligotrophic water. Even with practical oligotrophic water, BIADB still effectively removed 47.66-53.21 % (25 °C), and 39.26-45.63 % (10 °C) nitrate. The addition of inorganic electron donors increased nitrate removal by approximately 20 % for synthetic and practical water. Bacterial and functional communities exhibited significant temperature and stage differences (P < 0.05), with temperature and total dissolved nitrogen being the main environmental factors. The dominant genera and keystone taxa exhibited significant differences at the two temperatures. Structural equation model analysis showed that dissolved organic matter had the highest direct and indirect effects on diversity and function, respectively. This study provides an innovative pathway for utilizing biochar and inorganic electron donors for nitrate removal from oligotrophic waters.
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Carbón Orgánico , Nitratos , Agua , Nitratos/metabolismo , Agua/metabolismo , Desnitrificación , Electrones , Bacterias Aerobias/metabolismo , Bacterias/metabolismo , Nitrógeno/metabolismoRESUMEN
PURPOSE: Diabetes mellitus (DM-II) is a metabolic disorder either due to reduced insulin production or reduced insulin sensitivity. Diabetic foot ulcer (DFU) is one of the most devastating complications of DM-II. This study was performed to assess commonly isolated micro-organisms and their anti-microbial sensitivity pattern in diabetic foot ulcers in a tertiary care centre in Western Maharashtra. METHODS: Adult patients with a known case of DM-II with foot lesions, suspected to be a Diabetic Foot Infections (DFIs) at the tertiary care hospital from Aug 2022 to Sept 2022 were included in the study. After obtaining informed written consent, pus sample was collected with sterile swab from lesion's base and submitted to Microbiology Laboratory for aerobic culture and sensitivity. RESULTS: Out of 56 enrolled patients, 47 (83.9%) patients tested positive for bacteriological growth and there was 'no growth' in 9 (16.07%) patients at the end of 48 h of aerobic incubation. There was male preponderance and patients were in age group of 35-85 years. The most commonly isolated micro-organisms were P. aeruginosa (17.8%), followed by S. aureus (14.2%), K. pneumonia and P. mirabilis (12.5% each). The resistance markers observed was ESBL producer, AmpC producer, MBL producer, Methicillin resistance and Inducible Clindamycin Resistance (ICR). CONCLUSION: Due to the injudicious use of antibiotics, antibiotic resistance has been increased in all types of soft tissue infections. The empirical formula for the treatment of DFIs should be decided for given geographical reasons according to antimicrobial susceptibility profile from particular geographical area or health care institute.
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Antibacterianos , Pie Diabético , Pruebas de Sensibilidad Microbiana , Centros de Atención Terciaria , Humanos , Pie Diabético/microbiología , Pie Diabético/tratamiento farmacológico , Masculino , Femenino , Persona de Mediana Edad , Anciano , Adulto , India , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Anciano de 80 o más Años , Staphylococcus aureus/efectos de los fármacos , Pseudomonas aeruginosa/efectos de los fármacos , Bacterias Aerobias/efectos de los fármacos , Bacterias Aerobias/aislamiento & purificación , Klebsiella pneumoniae/efectos de los fármacosRESUMEN
BACKGROUND: Pseudomonas nitroreducens is a non-fermenting, gram-negative, rod-shaped bacterium commonly inhabiting soil, particularly soil contaminated with oil brine. To our knowledge, no cases of human infection with P. nitroreducens have been previously reported. Here, we present the first documented case of cholangitis caused by P. nitroreducens in a patient with bacteremia. CASE PRESENTATION: A 46-year-old Japanese man with an advanced pancreatic neuroendocrine tumor was hospitalized with fever and chills. Four days before admission, the patient developed right upper abdominal pain. Two days later, he also experienced fever and chills. Endoscopic retrograde cholangiopancreatography was performed on the day of admission, and the patient was diagnosed as having cholangitis associated with stent dysfunction. Gram-negative rods were isolated from blood cultures, but attempts to identify the bacteria using VITEK2 and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) with VITEK MS ver. 4.7.1 (bioMérieux Japan Co. Ltd., Tokyo, Japan) were unsuccessful. Finally, the organism was identified as P. nitroreducens using MALDI-TOF MS with a MALDI Biotyper (Bruker Daltonics Co., Ltd., Billerica, MA, USA) and 16 S ribosomal RNA sequencing. Despite thorough interviews with the patient, he denied any exposure to contaminated soil. The patient was treated with intravenous cefepime and oral ciprofloxacin for 16 days based on susceptibility results, achieving a good therapeutic outcome. At the outpatient follow-up on day 28, the patient was in good general condition. CONCLUSIONS: This is the first reported human case of cholangitis with bloodstream infection caused by P. nitroreducens. This report provides clinicians with novel insights into the clinical manifestations and diagnostic methods necessary for the accurate diagnosis of P. nitroreducens, along with guidance on treatment.
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Bacteriemia , Colangitis , Tumores Neuroendocrinos , Neoplasias Pancreáticas , Masculino , Humanos , Persona de Mediana Edad , Bacteriemia/diagnóstico , Bacteriemia/tratamiento farmacológico , Bacteriemia/microbiología , Bacterias , Pseudomonas , Bacterias Aerobias , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Colangitis/tratamiento farmacológico , Colangitis/etiología , SueloRESUMEN
The initial start-up attachment stage that dominates biofilm formation is an unstable process and is time-consuming. In the present study, Chlorella sp. was introduced into a general aerobic biofilm system to explore whether the addition of algae improved the initial attachment phase of biofilm. Compared with those of the bacterial biofilms, the initial algal-bacterial biofilms were more stable and had a thicker, denser, and rougher surface. Further investigation suggested that the concentration of extracellular polymeric substances (EPSs) in the algal-bacterial biofilm was 31.33 % greater than that in the bacterial biofilm. Additionally, the algal-bacterial flocs had greater free energies of absolute cohesion (ΔGcoh) and adhesion energy (∆Gadh) than did the bacterial flocs. These phenomena contribute to the speediness and stabilization of initial algal-bacterial start-up biofilms. Specifically, algae inoculation increased microbial community diversity and promoted the growth of bacterial members related to biofilm development. In conclusion, both physicochemical interactions and biological processes strongly influence microbial attachment during the initial biofilm formation process and further promote strengthening.
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Chlorella , Aguas Residuales , Biopelículas , Bacterias , Bacterias AerobiasRESUMEN
BACKGROUND: Weeksella virosa pneumonia is an infection that has been described as a healthcare-associated infection. This is a rare gram-negative anaerobic bacterium associated with the use of mechanical ventilation for a long period of time and is more frequent in immunosuppressed patients. This is the first case reported in the state of Veracruz and the second in Mexico. CASE PRESENTATION: We present the case of a 64-year-old female from Veracruz, Mexico who developed an infectious process in the right pelvic limb after a transcatheter aortic valve replacement procedure and subsequently developed sudden cardiorespiratory arrest requiring mechanical ventilation, with subsequent imaging studies demonstrating a pneumonic process associated with a nosocomial infection. DISCUSSION AND CONCLUSIONS: We should take into consideration that this pathogen affects not only adults with multiple comorbidities but also children with renal, hepatic, or oncological pathologies, as well as immunocompromised patients, who should be considered high-risk populations for W. virosa infection.
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Infección Hospitalaria , Neumonía Asociada al Ventilador , Adulto , Femenino , Niño , Humanos , Persona de Mediana Edad , Neumonía Asociada al Ventilador/diagnóstico , Composición de Base , Filogenia , ARN Ribosómico 16S , Análisis de Secuencia de ADN , Bacterias Aerobias , Infección Hospitalaria/diagnósticoRESUMEN
The activated sludge was collected from the Membrane BioReactor (MBR) pool of the sewage treatment system of Sanxing Town, Jintang County, Chengdu, to obtain a good population of heterotrophic nitrifying/aerobic denitrifying (HNAD) bacteria. After undergoing enrichment, isolation, and purification, the HNAD bacteria were selected using the pure culture method. The 16S rDNA molecular technology was used to determine the taxonomy of bacteria. The heterophic nitrifying ability and denitrification capacity of HNAD strains was ascertained through their growth characteristics in heterotrophic nitrification and denitrification media. The results showed that 53 HNAD strains selected from the MBR pool belonged to 2 phyla, 3 classes, 6 orders, 6 families, and 7 genera, with 26 species. Acinetobacter was the largest and dominant genus. Among these, strains numbered (bacterial strain) SW21HD14, SW21HD17, and SW21HD18 were potentially new species in the Acinetobacter genus. Each HNAD strain showed a significant heterotrophic nitrifying and aerobic denitrifying efficiency compared with the control strain (P < 0.05). Specifically, 10 strains demonstrated ammonia nitrogen degradation of greater than 70 mg·L-1 and 9 strains demonstrated nitrate nitrogen degradation above 150 mg·L-1. The HNAD bacteria, which were selected from the MBR pool of sewage treatment system of the Sanxing Town sewage treatment plant, exhibited rich diversity and strong nitrogen removal ability. These findings offered an effective strain source and theoretical basis for implementing biological denitrification technology that involves synchronous nitrification and denitrification.