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International Journal of Environmental... Jan 2022The phenylurea herbicides are persistent in soil and water, making necessary the de-velopment of techniques for their removal from the environment. To identify new...
The phenylurea herbicides are persistent in soil and water, making necessary the de-velopment of techniques for their removal from the environment. To identify new options in this regard, bacterial strains were isolated from a soil historically managed with pesticides. CD3 showed the ability to remove completely herbicides such as diuron, linuron, chlorotoluron and fluometuron from aqueous solution, and up to 89% of isoproturon. In the case of diuron and linuron, their main metabolite, 3,4-dichloroaniline (3,4-DCA), which has a higher toxicity than the parent compounds, was formed, but remained in solution without further degradation. CD3 was also tested for bioremediation of two different agricultural soils artificially contaminated with diuron, employing bioremediation techniques: (i) biostimulation, using a nutrient solution (NS), (ii) bioaugmentation, using CD3, and iii) bioavailability enhancement using 2-hydroxypropyl-β-cyclodextrin (HPBCD). When bioaugmentation and HPBCD were jointly applied, 50% of the diuron initially added to the soil was biodegraded in a range from 4.7 to 0.7 d. Also, 3,4-DCA was degraded in soil after the strain was inoculated. At the end of the soil biodegradation assay an ecotoxicity test confirmed that after inoculating CD3 the toxicity was drastically reduced.
Topics: Biodegradation, Environmental; Diuron; Feasibility Studies; Herbicides; Ochrobactrum; Soil; Soil Microbiology; Soil Pollutants
PubMed: 35162387
DOI: 10.3390/ijerph19031365 -
Clinical Nephrology Mar 2022, a ubiquitous Gram-negative bacterium of low virulence, is an increasingly recognized cause of infection in immunocompromised hosts such as patients with kidney failure...
INTRODUCTION
, a ubiquitous Gram-negative bacterium of low virulence, is an increasingly recognized cause of infection in immunocompromised hosts such as patients with kidney failure treated by dialysis.
CASE REPORT
We report the case of a male hemodialysis patient with a central venous catheter, who developed an asymptomatic blood stream infection caused by . The infection was cured, and the dialysis catheter salvaged with intravenous meropenem and an antibiotic lock solution with ciprofloxacin.
CONCLUSION
We identified 13 further cases of infection in hemodialysis patients and 10 cases in peritoneal dialysis patients in the literature. Antibiotic treatment depends on the results of susceptibility testing. In many patients, however, removal of the central venous or peritoneal dialysis catheter is required to cure the infection.
Topics: Anti-Bacterial Agents; Gram-Negative Bacterial Infections; Humans; Male; Ochrobactrum anthropi; Peritoneal Dialysis; Renal Dialysis
PubMed: 34958300
DOI: 10.5414/CN110692 -
BMC Infectious Diseases Dec 2021Ochrobactrum spp. are non-fermenting, Gram-negative bacilli that are regarded as emerging human pathogens of low virulence that can cause infections. The first...
BACKGROUND
Ochrobactrum spp. are non-fermenting, Gram-negative bacilli that are regarded as emerging human pathogens of low virulence that can cause infections. The first identified case of Ochrobactrum intermedium was reported in 1998 in a liver transplantation patient with liver abcess. There are no reports of infections in pediatric patients. Here, we report the first case of O. intermedium bacteremia in a pediatric patient.
CASE PRESENTATION
A two and a half years old male was admitted with fever, chills and nausea. He had been diagnosed as pineoblastoma and underwent surgical resection and chemotherapy. O. intermedium was isolated from his blood cultures and identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), however, the Vitek II automated system failed to identify the organism. Then the pathogen was confirmed by 16S rDNA sequencing and average nucleotide identity result (ANI) confirmed the precise identification of O. intermedium at genomic level. In addition, the patient recovered well after antibiotic combined therapy.
CONCLUSIONS
This, to our knowledge, is the first case of O. intermedium bacteremia in a pediatric patient with malignant tumor. Traditional biochemical identification methods such as API 20NE or VITEK2 system cannot differentiate O. anthropi and O. intermedium. MALDI-TOF may be a promising tool for rapid identification of microorganisms such as O. intermedium.
Topics: Bacteremia; Child, Preschool; Gram-Negative Bacterial Infections; Humans; Male; Neoplasms; Ochrobactrum
PubMed: 34906070
DOI: 10.1186/s12879-021-06938-3 -
BMC Cancer Nov 2021Children with acute lymphoblastic leukemia (ALL) undergoing chemotherapy experience a relatively high risk of infection. And the disturbance of gut microbiota is... (Observational Study)
Observational Study
BACKGROUND
Children with acute lymphoblastic leukemia (ALL) undergoing chemotherapy experience a relatively high risk of infection. And the disturbance of gut microbiota is generally believed to impair intestinal barrier function and may induce bacterial infections and inflammation. The study aimed to investigate the alterations in the gut microbiota and assess its relationship with chemotherapy-induced pneumonia in pediatric ALL patients.
METHODS
We conducted a case-control study with 14 cases affected by pneumonia and 44 unaffected subjects and characterized the physiological parameters and gut microbiota by microarray-based technique.
RESULTS
There were significant differences in α- and β-diversity in the affected group compared with the control group. At species level, the LEfSe analysis revealed that Enterococcus malodoratus, Ochrobactrum anthropi and Actinomyces cardiffensis were significantly abundant in the affected subjects. A receiver operating characteristic (ROC) curve yielded the area under the curve (AUC) of 0.773 for classification between the two groups. In addition, the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways involved in the bacterial secretion system were more enriched in the affected group than in the control group.
CONCLUSIONS
Gut microbiota alteration was associated with chemotherapy-induced pneumonia in pediatric ALL patients, which provided a new perspective on the personalized clinical care of pediatric ALL.
Topics: Adolescent; Antineoplastic Agents; Case-Control Studies; Child; Dysbiosis; Feces; Female; Gastrointestinal Microbiome; Humans; Induction Chemotherapy; Male; Pneumonia; Precursor Cell Lymphoblastic Leukemia-Lymphoma
PubMed: 34749705
DOI: 10.1186/s12885-021-08917-y -
Open Forum Infectious Diseases Oct 2021Automated identification systems may misidentify , the causative agent of brucellosis, which may be re-emerging in the United States as the result of an expanding feral...
Automated identification systems may misidentify , the causative agent of brucellosis, which may be re-emerging in the United States as the result of an expanding feral swine population. We present a case of likely associated with feral swine exposure that was misidentified as , a phylogenetic relative.
PubMed: 34660837
DOI: 10.1093/ofid/ofab473 -
BMC Biotechnology Sep 2021The unnatural amino acid, L-2-aminobutyric acid (L-ABA) is an essential chiral building block for various pharmaceutical drugs, such as the antiepileptic drug...
BACKGROUND
The unnatural amino acid, L-2-aminobutyric acid (L-ABA) is an essential chiral building block for various pharmaceutical drugs, such as the antiepileptic drug levetiracetam and the antituberculosis drug ethambutol. The present study aims at obtaining variants of ω-transaminase from Ochrobactrum anthropi (OATA) with high catalytic activity to α-ketobutyric acid through protein engineering.
RESULTS
Based on the docking model using α-ketobutyric acid as the ligand, 6 amino acid residues, consisting of Y20, L57, W58, G229, A230 and M419, were chosen for saturation mutagenesis. The results indicated that L57C, M419I, and A230S substitutions demonstrated the highest elevation of enzymatic activity among 114 variants. Subsequently, double substitutions combining L57C and M419I caused a further increase of the catalytic efficiency to 3.2-fold. This variant was applied for threonine deaminase/OATA coupled reaction in a 50-mL reaction system with 300 mM L-threonine as the substrate. The reaction was finished in 12 h and the conversion efficiency of L-threonine into L-ABA was 94%. The purity of L-ABA is 75%, > 99% ee. The yield of L-ABA was 1.15 g.
CONCLUSION
This study provides a basis for further engineering of ω-transaminase for producing chiral amines from keto acids substrates.
Topics: Aminobutyrates; Catalytic Domain; Ochrobactrum anthropi; Transaminases
PubMed: 34563172
DOI: 10.1186/s12896-021-00713-7 -
Bioresource Technology Nov 2021The study aimed to isolate a novel strain with heterotrophic nitrification and aerobic denitrification ability and evaluate the nitrogen removal characteristics. Results...
The study aimed to isolate a novel strain with heterotrophic nitrification and aerobic denitrification ability and evaluate the nitrogen removal characteristics. Results showed that Ochrobactrum anthropi HND19 could remove approximately 98.6% of NH-N (104.3 mg·L) and 97.6% of NO-N (98.6 mg·L), and the removal rates achieved 4.28 and 4.01 mg-N/(L·h) by heterotrophic nitrification and aerobic denitrification. The optimal incubate conditions of strain HND19 were 120 rpm (shaking speed), 5 ‰ (salinity), 30 °C (temperature), 7.5 (C/N ratio) with sodium acetate as carbon resource. And the removal efficiency of the total nitrogen (TN) realized 73.4% under the optimal conditions. Functional genes (hao, napA, nirK, norB, and nosZ) involved in the nitrogen removal processes were successfully amplified from strain HND19. These findings indicate that the strain HND19 possesses great application feasibility in treating wastewater with high-intensity nitrogen.
Topics: Aerobiosis; Denitrification; Heterotrophic Processes; Nitrification; Nitrites; Nitrogen; Ochrobactrum anthropi
PubMed: 34332445
DOI: 10.1016/j.biortech.2021.125582 -
ACS Chemical Biology Aug 2021Pantothenic acid is an essential metabolite found throughout all branches of life. Although the enzymes responsible for pantothenic biosynthesis have been characterized,...
Pantothenic acid is an essential metabolite found throughout all branches of life. Although the enzymes responsible for pantothenic biosynthesis have been characterized, those leading to its biodegradation remain poorly understood. In the study described herein, we showed that use of a "genomic enzymology" strategy enabled identification of four biodegradation pathway genes, which were then confirmed by using kinetic analysis of the purified recombinant enzymes encoded in . The reconstituted pathway converts pantothenic acid to β-alanine and ()-pantoate, and then ()-pantoate to aldopentoate, which is transformed to ()-3,3-dimethylmalate and hence to α-ketoisovalerate. The pathway genes are common to Proteobacterial genomes in which they are not colocated.
Topics: Amidohydrolases; Genes, Bacterial; Genomics; Multigene Family; NAD (+) and NADP (+) Dependent Alcohol Oxidoreductases; Ochrobactrum anthropi; Pantothenic Acid
PubMed: 34313416
DOI: 10.1021/acschembio.1c00492 -
Ocular Immunology and Inflammation 2022To report the clinical presentation and management outcomes of an outbreak of culture-proven post-operative endophthalmitis (POE) secondary to .
AIM
To report the clinical presentation and management outcomes of an outbreak of culture-proven post-operative endophthalmitis (POE) secondary to .
METHODS
This study was conducted at a tertiary-care eye hospital in South India.
RESULTS
Fifty-five patients underwent cataract surgery by six surgeons on three consecutive days in the same surgical facility in September 2020. Four patients developed POE after a mean interval of 12.0 ± 4.8 days and underwent immediate vitreous tap and intravitreal antibiotic injections (Vancomycin and Ceftazidime). All patients required a core vitrectomy (culture positive, n = 4/4). Two patients underwent an additional intraocular lens explantation, 2 and 4 months after presentation. All the four patients showed good anatomical and functional recoveries (mean follow-up, 5.75 ± 1.5 months). Two other patients had an exaggerated post-operative inflammation, which was successfully treated with topical medications.
CONCLUSIONS
is a rare cause of acute POE. Although the isolated organism was multi-drug resistant, the outcome was good in all the patients.
Topics: Humans; Ochrobactrum anthropi; India
PubMed: 34213986
DOI: 10.1080/09273948.2021.1945636 -
Acta Biochimica Et Biophysica Sinica Aug 2021Vibrio natriegens is known to be the fastest-growing free-living bacterium with the potential to be a novel protein expression system other than Escherichia coli. Seven...
Vibrio natriegens is known to be the fastest-growing free-living bacterium with the potential to be a novel protein expression system other than Escherichia coli. Seven sampled genes of interest (GOIs) encoding biocatalyst enzymes, including Ochrobactrum anthropi-derived ω-transaminase (OATA), were strongly expressed in E. coli but weakly in V. natriegens using the pET expression system. In this study, we fused the C-terminal of OATA with green fluorescent protein (GFP) and obtained V. natriegens mutants that could increase both protein yield and enzyme activity of OATA as well as the other three GOIs by ultraviolet mutagenesis, fluorescence-activated cell sorting (FACS), and OATA colorimetric assay. Furthermore, next-generation sequencing and strain reconstruction revealed that the Y457 variants in the conserved site of endogenous RNA polymerase (RNAP) β' subunit rpoC are responsible for the increase in recombinant protein yield. We speculated that the mutation of rpoC Y457 may reprogram V. natriegens's innate gene transcription, thereby increasing the copy number of pET plasmids and soluble protein yield of certain GOIs. The increase in GOI expression may partly be attributed to the increase in copy number. In conclusion, GOI-GFP fusion combined with FACS is a powerful tool of forward genetics that can be used to obtain a superior expression chassis. If more high-expression-related targets are found for more GOIs, it would make the construction of next-generation protein expression chassis more time-saving.
Topics: Biotechnology; DNA-Directed RNA Polymerases; Flow Cytometry; Green Fluorescent Proteins; High-Throughput Nucleotide Sequencing; High-Throughput Screening Assays; Molecular Biology; Mutagenesis; Ochrobactrum anthropi; Plasmids; Recombinant Proteins; Transaminases; Vibrio
PubMed: 34169308
DOI: 10.1093/abbs/gmab089