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Saudi Journal of Biological Sciences Jan 2021Metabolites of azo dyes are often carcinogenic, teratogenic, mutagenic and recalcitrant in nature. In this study, four biofilm consortia such as C1 ( sp. ENSG301,...
Metabolites of azo dyes are often carcinogenic, teratogenic, mutagenic and recalcitrant in nature. In this study, four biofilm consortia such as C1 ( sp. ENSG301, ENSG302, ENSG303 and ENSG304), C2 ( ENSD101, ENSD102 and ENSH201), C3 ( ENSD102, sp. ENSG301 and ENSW401), and C4 ( ENSD101, ENSH201 and ENSW401) were applied to degrade and detoxify methyl orange (MO), a carcinogenic, sulfonated mono azo dye, used in textile dyeing industry worldwide. The consortia of C1, C2, C3 and C4 showed 97.30, 98.75, 99.51 and 99.29% decolorization, respectively in yeast extract peptone (YEP) broth containing 200 mg L MO within 60 h of incubation in static condition. The optimum pH and temperature for decolorization was 7.0 and 28 °C, respectively. Some divalent metal ions including Mg, Ca, Zn and Mn could stimulate MO decolorization. UV-Vis spectral analysis showed that the absorption peak at 465 nm originated from the azo (N[bond, double bond]N) bond was completely disappeared within 60 h of incubation. Fourier transform infrared spectroscopy (FTIR) results also revealed that several major peaks including azo bond peak at 1602.6 cm are completely or partly vanished, deformed or shifted. Activities of azoreductase, NADH-DCIP reductase and laccase were significantly increased in the bacterial cells within 60 h of incubation in comparison to that of control (0 h). The chemical oxygen demand was incredibly reduced by 85.37 to 91.44% by these consortia. Accordingly, plant (wheat seed germination) and microbial (growth of the plant probiotic bacteria such as ESR12 and ESD3 on biodegraded products) toxicity studies showed that biodegraded products of MO are non-toxic. Thus, all these consortia can be utilized in bioremediation of MO from wastewater for safe disposal into environment. To our knowledge, this is the first report on degradation and detoxification of MO from wastewater by bacterial biofilm consortia.
PubMed: 33424369
DOI: 10.1016/j.sjbs.2020.11.012 -
Iranian Journal of Microbiology Oct 2019In recent years, reports of strains resistant to all known antibiotics have caused a great concern in medical communities. Overexpression of efflux pumps is one of the...
BACKGROUND AND OBJECTIVES
In recent years, reports of strains resistant to all known antibiotics have caused a great concern in medical communities. Overexpression of efflux pumps is one of the major causes of resistance in bacteria. The aim of this study was to investigate the role of efflux pumps in conferring resistance to imipenem in clinically important and .
MATERIALS AND METHODS
A total number of 46 clinical isolates, including 33 and 13 isolates, previously collected from Shahid Kamyab and Ghaem hospitals of Mashhad, Iran were used in this study. Imipenem susceptibility testing was carried out by the disc diffusion method. Imipenem minimum inhibitory concentration (MIC) for resistant isolates were determined both in the presence and absence of the efflux pumps inhibitor, carbonyl cyanide 3-chlorophenylhydrazone (CCCP).
RESULTS
Resistance to imipenem was observed in 38 isolates including 30 and 8 isolates. Experiments in the presence of CCCP showed a 2 to 16384 fold reduction in imipenem MICs in 14 and 2 isolates.
CONCLUSION
The results obtained showed high levels of resistance to imipenem and contribution of efflux pumps in conferring resistance in both species in this study. Moreover, imipenem efflux mediated resistance highlights the importance of this mechanism not only in but also in non- Spp. which have been neglected in antibiotic resistance studies.
PubMed: 32148666
DOI: No ID Found -
Journal of Dairy Science Jan 2018Refrigerated raw milk may contain psychrotrophic microorganisms that produce thermoresistant exoproteases and lipases, which may compromise the quality of processed...
Refrigerated raw milk may contain psychrotrophic microorganisms that produce thermoresistant exoproteases and lipases, which may compromise the quality of processed fluid milk and dairy products during storage. The aim of this work was to quantify and identify the deteriorating psychrotrophic microbiota in Brazilian refrigerated raw milk using genetic diversity analysis. The mean psychrotrophic count was 1.1 × 10 cfu/mL. Of the total isolates, 47.8 and 29.8% showed deteriorating activity at 35°C within 48 h and 7°C within 10 d, respectively. Among the proteolytic species, more isolated by this study were Lactococcus lactis (27.3%), Enterobacter kobei (14.8%), Serratia ureilytica (8%), Aerococcus urinaeequi (6.8%), and Bacillus licheniformis (6.8%). Observed among lipolytics were E. kobei (17.7%), L. lactis (15.6%), A. urinaeequi (12.5%), and Acinetobacter lwoffii (9.4%). The isolates S. ureilytica, E. kobei, Pseudomonas spp., and Yersinia enterocolitica potentially produced alkaline metalloprotease (aprX). Despite the low counts, a considerable portion of the psychrotrophic microbiota presented spoilage potential, which reaffirms the need for rigor in the control of contamination and the importance of rapid processing as factors that maintain the quality of milk and dairy products.
Topics: Animals; Bacteria; Bacterial Proteins; Brazil; Cattle; Food Microbiology; Lipase; Microbiota; Milk
PubMed: 29102138
DOI: 10.3168/jds.2017-13069 -
Antimicrobial Stewardship & Healthcare... 2023To describe antimicrobial therapy used for multidrug-resistant (MDR) bacteremia in Veterans and impacts on mortality.
OBJECTIVE
To describe antimicrobial therapy used for multidrug-resistant (MDR) bacteremia in Veterans and impacts on mortality.
METHODS
This was a retrospective cohort study of hospitalized Veterans Affairs patients from 2012 to 2018 with a positive MDR blood culture who received antimicrobial treatment 2 days prior to through 5 days after the culture date. Only the first culture per patient was used. The association between treatment and patient characteristics was assessed using bivariate analyses. Multivariable logistic regression models examined the relationship between antibiotic regimen and in-hospital, 30-day, and 1-year mortality. Generalized linear models were used to assess cost outcomes.
RESULTS
MDR was identified in 184 patients. Most cultures identified were , 3% were and 7% were other Penicillins-β-lactamase inhibitor combinations (51.1%) and carbapenems (51.6%)-were the most prescribed antibiotics. In unadjusted analysis, extended spectrum cephalosporins and penicillins-β-lactamase inhibitor combinations-were associated with a decreased odds of 30-day mortality but were insignificant after adjustment (adjusted odds ratio (aOR) = 0.47, 95% CI, 0.21-1.05, aOR = 0.75, 95% CI, 0.37-1.53). There was no association between combination therapy vs monotherapy and 30-day mortality (aOR = 1.55, 95% CI, 0.72-3.32).
CONCLUSION
In hospitalized Veterans with MDR ., none of the treatments were shown to be associated with in-hospital, 30-day, and 1-year mortality. Combination therapy was not associated with decreased mortality for MDR bacteremia.
PubMed: 38156232
DOI: 10.1017/ash.2023.500 -
Applied Microbiology and Biotechnology Aug 2023While the in situ return of corn straw can improve soil fertility and farmland ecology, additional bacterial agents are required in low-temperature areas of northern...
While the in situ return of corn straw can improve soil fertility and farmland ecology, additional bacterial agents are required in low-temperature areas of northern China to accelerate straw degradation. Moisture is an important factor affecting microbial activity; however, owing to a lack of bacterial agents adapted to low-temperature complex soil environments, the effects of soil moisture on the interaction between exogenous bacterial agents and indigenous soil microorganisms remain unclear. To this end, we explored the effect of the compound bacterial agent CFF constructed using Pseudomonas putida and Acinetobacter lwoffii, developed to degrade corn straw in low-temperature soils (15 °C), on indigenous bacterial and fungal communities under dry (10% moisture content), slightly wet (20%), and wet (30%) soil-moisture conditions. The results showed that CFF application significantly affected the α-diversity of bacterial communities and changed both bacterial and fungal community structures, enhancing the correlation between microbial communities and soil-moisture content. CFF application also changed the network structure and the species of key microbial taxa, promoting more linkages among microbial genera. Notably, with an increase in soil moisture, CFF enhanced the rate of corn straw degradation by inducing positive interactions between bacterial and fungal genera and enriching straw degradation-related microbial taxa. Overall, our study demonstrates the alteration of indigenous microbial communities using bacterial agents (CFF) to overcome the limitations of indigenous microorganisms for in situ straw-return agriculture in low-temperature areas. KEY POINTS: • Low-temperature and variable moisture conditions (10-30%) were compared • Soil microbial network structure and linkages between genera were altered • CFF improves straw degradation via positive interactions between soil microbes.
Topics: Zea mays; Temperature; Soil Microbiology; Agriculture; Soil; Bacteria
PubMed: 37392246
DOI: 10.1007/s00253-023-12644-8 -
Journal of Laboratory Physicians Sep 2023species has become a leading cause of nosocomial infections in recent years. The aim of the study was to establish the usefulness of matrix-assisted laser...
species has become a leading cause of nosocomial infections in recent years. The aim of the study was to establish the usefulness of matrix-assisted laser desorption ionization-time-of-flight (MALDI-TOF) mass spectrometry (MS) for the identification of species with respect to conventional biochemical methods and MicroScan WalkAway 96 Plus system and to compare the antibiotic susceptibility test results Kirby-Bauer disk diffusion method with MicroScan WalkAway 96 Plus automated identification and antimicrobial susceptibility testing system. The study sample comprised 100 clinical isolates of species. They were all identified using MALDI-TOF MS and compared with other two identification systems. Comparison of categorical variables by Fisher's exact test or Pearson's chi-square test was done. All statistical tools were two tailed, and a significant level < 0.05 was used. All statistical tests were performed using SPSS v22.0 (Armonk IBM Corp., New York, United States). Cohen's kappa coefficients were also calculated and used as applicable. MALDI-TOF MS revealed 92 , 2 , 3 , and 1 each was identified as , , and . There was moderate agreement between identification by MicroScan WalkAway and MALDI-TOF, and substantial agreement between conventional biochemical tests and MALDI-TOF. We found that there was a 100% categorical agreement with respect to susceptibility of aminoglycosides (amikacin, gentamicin, tobramycin) and cephalosporins (ceftazidime, cefepime, cefotaxime) between disk diffusion method and MicroScan WalkAway 96 Plus system. Total of 16 errors were observed. Although MALDI-TOF MS could be useful to identify but not other species in the genus, it is a rapid, reliable method and can be routinely used in clinical laboratories.
PubMed: 37564221
DOI: 10.1055/s-0042-1760401 -
Genome Biology Mar 2020While the physical and chemical properties of airborne particulate matter (PM) have been extensively studied, their associated microbiome remains largely unexplored....
BACKGROUND
While the physical and chemical properties of airborne particulate matter (PM) have been extensively studied, their associated microbiome remains largely unexplored. Here, we performed a longitudinal metagenomic survey of 106 samples of airborne PM and PM in Beijing over a period of 6 months in 2012 and 2013, including those from several historically severe smog events.
RESULTS
We observed that the microbiome composition and functional potential were conserved between PM and PM, although considerable temporal variations existed. Among the airborne microorganisms, Propionibacterium acnes, Escherichia coli, Acinetobacter lwoffii, Lactobacillus amylovorus, and Lactobacillus reuteri dominated, along with several viral species. We further identified an extensive repertoire of genes involved in antibiotic resistance and detoxification, including transporters, transpeptidases, and thioredoxins. Sample stratification based on Air Quality Index (AQI) demonstrated that many microbial species, including those associated with human, dog, and mouse feces, exhibit AQI-dependent incidence dynamics. The phylogenetic and functional diversity of air microbiome is comparable to those of soil and water environments, as its composition likely derives from a wide variety of sources.
CONCLUSIONS
Airborne particulate matter accommodates rich and dynamic microbial communities, including a range of microbial elements that are associated with potential health consequences.
Topics: Air Pollution; China; Cities; Environmental Monitoring; Metagenome; Metagenomics; Microbiota; Smog
PubMed: 32127018
DOI: 10.1186/s13059-020-01964-x -
La Tunisie MedicalePeritonitis is an important cause of morbidity and technique failure in peritoneal dialysis. Herein, we report peritonitis related to Acinetobacter lwoffi in two...
Peritonitis is an important cause of morbidity and technique failure in peritoneal dialysis. Herein, we report peritonitis related to Acinetobacter lwoffi in two patients on peritoneal dialysis. The first case is a 63-year-old patient treated by automated peritoneal dialysis admitted with abdominal pain. The peritoneal effluent White Blood Cells count consisted of 280 cells/mm3. Then culture identified a multisensitive Acinetobacter lwoffi. Treatment with ceftazidime and ciprofloxacin had been started. The control dialysate culture was sterile after three weeks. The second patient is a 59-year-old female admitted because of diffuse abdominal pain and cloudy dialysate. The peritoneal effluent White Blood Cells count consisted of countless leukocytes, with predominantly polynuclear and culture identified Acinetobacter lwoffi. He received intraperitoneal ceftazidim and amikacin for three weeks. The control dialysate was sterile. Acinetobacter lwoffi is a rare cause of peritonitis and it can be treated successfully with early recognition and appropriate antibiotic therapy based on culture instead of catheter removal.
Topics: Abdominal Pain; Acinetobacter; Amikacin; Anti-Bacterial Agents; Ceftazidime; Ciprofloxacin; Dialysis Solutions; Female; Humans; Male; Middle Aged; Peritoneal Dialysis; Peritonitis
PubMed: 36206068
DOI: No ID Found -
Frontiers in Oncology 2020The gut microbiota is reported to play an important role in carcinogenesis and the treatment of CRC. SW480 and SW620 colon cancer cells integrated with infrared...
The gut microbiota is reported to play an important role in carcinogenesis and the treatment of CRC. SW480 and SW620 colon cancer cells integrated with infrared fluorescent proteins were injected into the rectal submucosa of nude mice. In the subsequent 30 days, we observed tumor growth weekly using an imaging system. The bacterial solution was infused anally into the mice to perform bacterial transplant. Phosphate-buffered saline, , and solutions were infused individually. The 16S ribosomal DNA (rDNA) and polymerase chain reaction of murine feces were investigated to confirm the colonization of target bacteria. In the SW620 orthotopic xenograft rectal cancer model, 4 of 5 mice developed rectal cancer by 30 days after submucosal injection. In the SW480 orthotopic xenograft rectal cancer model, 2 of 6 mice developed rectal cancer by 30 days after submucosal injection. For the 16S rDNA analysis, the mice receiving the bacterial solution infusion demonstrated positive findings for and . With the successful establishment of a mouse model of orthotopic rectal cancer and transplant of target bacteria, we can further explore the relationship between gut microbiota and CRC. The role of fecal microbiota transplant in the treatment and alleviation of adverse events of chemotherapy in CRC could be clarified in subsequent studies.
PubMed: 33194651
DOI: 10.3389/fonc.2020.568012 -
The Journal of Veterinary Medical... Oct 2017A 10-month-old male Welsh Corgi with a history of acute blindness underwent neuro-ophthalmological testing and magnetic resonance imaging (MRI). Vision testing revealed...
A 10-month-old male Welsh Corgi with a history of acute blindness underwent neuro-ophthalmological testing and magnetic resonance imaging (MRI). Vision testing revealed complete visual deficits but the electroretinograph and pupillary light reflex were normal in both eyes. The motor and sensory functions of the eyelids and eyes were also normal. The MRI revealed compression of the optic chiasm caused by severe ventriculomegaly in the lateral and third ventricles. Such lesions are associated with inflammatory stenotic lesions in the mesencephalic aqueduct. Moderate neutrophilic pleocytosis was observed during cerebrospinal fluid analysis and Acinetobacter lwoffii was isolated, leading to a diagnosis of Acinetobacter-positive obstructive hydrocephalus. This is the first reported case of culture-proven Acinetobacter-associated postencephalitic hydrocephalus with acute blindness in a dog.
Topics: Acinetobacter; Acinetobacter Infections; Animals; Blindness; Cat Diseases; Cats; Cerebral Ventricles; Dogs; Encephalitis; Hydrocephalus; Leukocytosis; Magnetic Resonance Imaging; Male; Neutrophils
PubMed: 28855429
DOI: 10.1292/jvms.17-0075