Ochrobactrum anthropi infection following corneal transplantation -a case report and review of literature.

BACKGROUND: Ochrobactrum anthropi is widely distributed and primarily infects patients with compromised immune functions . Historically, O. anthropi has been considered to possess low toxicity and pathogenicity; however, recent studies suggest that it may in fact cause severe purulent infections. In this case study, we examine a case of O. anthropi infection following corneal transplantation, exploring the occurrence and outcomes of such post-operative infections. CASE PRESENTATION: A retrospective analysis of cases involved examinations, genetic testing for diagnosis, and subsequent treatment. In patients undergoing partial penetrating keratoplasty with a fungal corneal ulcer perforation, anterior chamber exudation and purulence were observed post-surgery. Despite antifungal treatment, genetic testing of the anterior chamber fluid and purulent material confirmed O. anthropi infection. The use of antimicrobial treatment specifically targeting O. anthropi was found to be effective in treating the infection. CONCLUSION: Inflammatory reactions following corneal transplantation should be should be monitored for the presence of other infections. Genetic testing has significant implications for clinical diagnosis and treatment.

Ochrobactrum Anthropi; an Unusual Cause of Bacteremia and Pneumonia: A Case Report and a Brief Review of the Literature.

Background: Ochrobactrum anthropi spp. is a non-enteric, aerobic gram-negative bacillus that has been reported to cause sepsis and occasionally bacteremia in both immunocompetent and immunocompromised hosts. This bacterium is capable of surviving in various habitats, but due to its affinity for aqueous environments, O. anthropi is hypothesized to have an affinity for indwelling plastic devices and other foreign bodies.

Case Presentation: We report a case of a 66 y/o male with a history of polysubstance abuse disorder admitted for toxic metabolic encephalopathy and found to have bronchopneumonia and bacteremia secondary to O. anthropi infection resulting in sepsis and cardiopulmonary arrest.

Discussion: Ochrobactrum spp. is an unusual pathogen of low virulence and has been noted to cause bacteremia and occasionally sepsis in both immunocompetent and immunosuppressed patients. Isolation of this pathogen in the appropriate setting should be considered a true pathogen and treated as such to avoid sequela of this infection.

Conclusion: This case report and literature review suggest that Ochrobactrum anthropi appears more frequently as a pathogen in nosocomial infections than suggested in the literature.

Biosynthesis of vanillic acid by Ochrobactrum anthropi and its applications.

Vanillic acid has always been in high-demand in pharmaceutical, cosmetic, food, flavor, alcohol and polymer industries. Present study achieved highly pure synthesis of vanillic acid from vanillin using whole cells of Ochrobactrum anthropi strain T5_1. The complete biotransformation of vanillin (2 g/L) in to vanillic acid (2.2 g/L) with 95 % yield was achieved in single step in 7 h, whereas 5 g/L vanillin was converted to vanillic acid in 31 h. The vanillic acid thus produced was validated using LC-MS, GC-MS, FTIR and NMR. Further, vanillic acid was evaluated for in vitro anti-tyrosinase and cytotoxic properties on B16F1 skin cell line in dose dependent manner with IC50 values of 15.84 mM and 9.24 mM respectively. The in silico Swiss target study predicted carbonic acid anhydrase IX and XII as key targets of vanillic acid inside the B16F1 skin cell line and revealed the possible mechanism underlying cell toxicity. Molecular docking indicated a strong linkage between vanillic acid and tyrosinase through four hydrogen and several hydrophobic bonds, with ΔG of -3.36 kJ/mol and Ki of 3.46 mM. The bioavailability of vanillic acid was confirmed by the Swiss ADME study with no violation of Lipinski's five rules.

Whole-genome analysis and description of an IMP-8-producing Ochrobactrum anthropi.

OBEJECTIVES: To explore the genomic characterization of an IMP-8-producing Ochrobactrum anthropic and give suggestions for the application of antibiotics. METHODS: In 2021, the infection caused by CRKP was under control after nearly three months of using CAV, however, carbapenem-resistant O. anthropi isolates were collected from a rectal swab sample of a patient with Lumbar Disc Herniation Postoperative Infection. The rectal swab was then enriched in lysogeny broth overnight and inoculated onto China Blue agar plates containing 0.3µg/mL meropenem. And we investigated the characteristics of this carbapenem-resistant O. anthropi by MALDI-TOF MS, Immune colloidal gold technique, conjugation experiment, whole genome sequencing and antimicrobial susceptibility testing. RESULTS: Antimicrobial susceptibility testing showed that the O. anthropi were resistant to imipenem, cefmetazole, ceftazidime, cefotaxime, piperacillin/tazobactam, sulbactam/cefopcrazone, ceftazidime/avibactam, cefepime, ciprofloxacin, aztreonam, and not susceptible to meropenem, ertapenem, polymyxin B, tigecycline, amikacin. Immune colloidal gold technique reflected that this strain produced IMP carbapenemases, and the presence of IMP-8 was verified by WGS, which was located in a 21,442 bp, nonconjugative plasmid. CONCLUSION: Improper antibiotic treatment can cause intestinal flora imbalance and even bacteremia in patients, we should use antibiotics wisely and develop individualized treatment options.

Ochrobactrum anthropi: A Rare Cause of Culture-Proven Acute Post-Operative Cluster Endophthalmitis.

AIM: To report the clinical presentation and management outcomes of an outbreak of culture-proven post-operative endophthalmitis (POE) secondary to Ochrobactrum anthropi. 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: O. anthropi is a rare cause of acute POE. Although the isolated organism was multi-drug resistant, the outcome was good in all the patients.

Ochrobactrum anthropi infection in dialysis patients: A case report and literature summary.

INTRODUCTION: Ochrobactrum anthropi, 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 Ochrobactrum anthropi. 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 Ochrobactrum 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.

Active-site engineering of ω-transaminase from Ochrobactrum anthropi for preparation of L-2-aminobutyric acid.

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.

Simultaneous nitrification and aerobic denitrification by a novel isolated Ochrobactrum anthropi HND19.

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 NH4+-N (104.3 mg·L-1) and 97.6% of NO3--N (98.6 mg·L-1), 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.

In Vitro Reconstitution of the Pantothenic Acid Degradation Pathway in Ochrobactrum anthropi.

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 Ochrobactrum anthropi. The reconstituted pathway converts pantothenic acid to ß-alanine and (R)-pantoate, and then (R)-pantoate to aldopentoate, which is transformed to (R)-3,3-dimethylmalate and hence to α-ketoisovalerate. The pathway genes are common to Proteobacterial genomes in which they are not colocated.

A novel global transcriptional perturbation target identified by forward genetics reprograms Vibrio natriegens for improving recombinant protein production.

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) ß' 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.

Tunnelled hemodialysis catheter-related bloodstream infection with Ochrobactrum anthropi: a report of the first two cases from Bulgaria and a brief overview.

The use of central venous catheters for hemodialysis continues to grow worldwide, despite the efforts of many specialists. Patients with end-stage renal disease have impaired immunity, which is why infections are the most common complication seen in them. It worsens their quality of life and is a major cause of high morbidity and mortality, especially in hemodialysis patients.We report two cases of catheter-related bloodstream infection in hemodialysis patients caused by Ochrobactrum anthropi, which are the first reported cases in Bulgaria and present a brief literature review of the known facts.

Efficient reduction of reactive black 5 and Cr(â ¥) by a newly isolated bacterium of Ochrobactrum anthropi.

It is important to obtain bacteria with the ability for reduction of dyes and Cr(Ⅵ) since dyes and Cr(Ⅵ) are often co-exist in textile wastewater. In this study, a new strain belonging to Ochrobactrum anthropi was isolated from textile wastewater, and could efficiently reduce Reactive Black 5 (RB 5) and Cr(Ⅵ). The results showed the degradation efficiency of RB 5 could achieve 100% and reduction efficiency of Cr(Ⅵ) was up to 80% within 3 days at initial RB 5 and Cr(Ⅵ) concentration of 400 mg/L and 20 mg/L. Mn2+ and Cu2+ could enhance the removal of RB 5 and Cr(Ⅵ), respectively. Glycerin, as electron donor, improved reduction efficiencies of RB 5 and Cr(Ⅵ). In addition, reduction mechanisms were further investigated. The results demonstrated that decreasing of RB 5 and Cr(Ⅵ) concentration were mainly through extracellular bioreduction rather than by adsorption. The FTIR and XPS analyses revealed that the O‒H, C‒C and C‒H groups on the cell surface might be involved in the reduction of RB 5 and Cr(Ⅵ). The information gives useful insights into understanding of how the bacterium reduce RB 5 and Cr(Ⅵ). The results indicated that the strain had excellent application prospect for treating industrial wastewater.

Ochrobactrum anthropi Keratitis in a Boston Type 1 Keratoprosthesis Recipient.

PURPOSE: To report a case of Ochrobactrum anthropi keratitis in an eye with a Boston type 1 keratoprosthesis. METHODS: This is a case report and review of the literature. RESULTS: A 78-year-old man with a history of implantation of a Boston type 1 keratoprosthesis in the left eye presented for a routine follow-up with no acute complaints. In the left eye, visual acuity was 20/60 and slit-lamp examination revealed a 1.5-mm inferotemporal corneal infiltrate adjacent to the optic stem. Corneal cultures grew abundant O. anthropi. After 7 weeks of topical antimicrobial therapy and placement of a temporary tarsorrhaphy, the keratitis resolved. CONCLUSIONS: Ochrobactrum anthropi is an organism associated with indwelling medical devices and can be pathogenic in eyes with implanted keratoprostheses.

Cellular strategies against metal exposure and metal localization patterns linked to phosphorus pathways in Ochrobactrum anthropi DE2010.

Cytotoxic, chemical, biochemical, compositional, and morphometric responses were analyzed against heavy metal exposure in Ochrobactrum anthropi DE2010, an heterotrophic bacterium isolated from Ebro Delta microbial mats (Tarragona, NE Spain). Several parameters of effect and exposure were evaluated to determine tolerance to a range of cadmium (Cd), lead (Pb(II)), copper (Cu(II)), chromium (Cr(III)), and zinc (Zn) concentrations. Additionally, removal efficiency, polyphosphate production and metal localization patterns were also analyzed. O. anthropi DE2010 showed high resistance to the tested metals, supporting concentrations of up to 20 mM for Zn and 10 mM for the rest of the elements. The bacterium also demonstrated a high removal capacity of metals-up to 90 % and 40 % for Pb(II) and Cr(III), respectively. Moreover, polyphosphate production was strongly correlated with heavy metal concentration, and three clear cell localization patterns of metals were evidenced using compositional and imaging techniques: (i) extracellular in polyphosphate granules for Cu(II); (ii) in periplasmic space forming crystals with phosphorus for Pb(II); and (iii) intracytoplasmic in polyphosphate inclusions for Pb(II), Cr(III), and Zn. The high resistance and metal sequestration capacity of O. anthropi DE2010 both highlight its great potential for bioremediation strategies, especially in Pb and Cr polluted areas.

Evaluating the Effect of Azole Antifungal Agents on the Stress Response and Nanomechanical Surface Properties of Ochrobactrum anthropi Aspcl2.2.

Azole antifungal molecules are broadly used as active ingredients in various products, such as pharmaceuticals and pesticides. This promotes their release into the natural environment. The detailed mechanism of their influence on the biotic components of natural ecosystems remains unexplored. Our research aimed to examine the response of Ochrobactrum anthropi AspCl2.2 to the presence of four azole antifungal agents (clotrimazole, fluconazole, climbazole, epoxiconazole). The experiments performed include analysis of the cell metabolic activity, cell membrane permeability, total glutathione level and activity of glutathione S-transferases. These studies allowed for the evaluation of the cells' oxidative stress response to the presence of azole antifungals. Moreover, changes in the nanomechanical surface properties, including adhesive and elastic features of the cells, were investigated using atomic force microscopy (AFM) and spectrophotometric methods. The results indicate that the azoles promote bacterial oxidative stress. The strongest differences were noted for the cells cultivated with fluconazole. The least toxic effect has been attributed to climbazole. AFM observations unraveled molecular details of bacterial cell texture, structure and surface nanomechanical properties. Antifungals promote the nanoscale modification of the bacterial cell wall. The results presented provided a significant insight into the strategies used by environmental bacterial cells to survive exposures to toxic azole antifungal agents.

Genomic and biotechnological insights on stress-linked polyphosphate production induced by chromium(III) in Ochrobactrum anthropi DE2010.

The resistance of microorganisms to heavy metals in polluted environments is mediated by genetically determined mechanisms. One such mechanism includes the intracellular sequestration of heavy metals in polyphosphate (polyP) inclusions. In Cr(III) contaminated mediums, Ochrobactrum anthropi DE2010 is able to bind and sequester Cr(III) in polyP inclusions. In order to further study the relationship between Cr(III) tolerance and polyP production in O. anthropi DE2010, we carried out whole genomic sequencing, analysis of single nucleotide polymorphisms (SNPs), polyP chemical quantification, and determination of the relative abundance and morphometry of polyP inclusions. In the O. anthropi DE2010 genome, six polyP and pyrophosphate (PPi) metabolic genes were found. Furthermore, genomic analysis via SNPs calling revealed that O. anthropi ATCC49188 and DE2010 strains had average variations of 1.51% in their whole genome sequences and 1.35% variation associated with the principal polyP metabolic gene cluster. In addition, the accumulation of polyP in the DE2010 strain and number of polyP inclusions found were directly correlated with the concentration of Cr(III) in contaminated cultures. The results presented in this study may enhance the understanding of polyP production in response to Cr(III) toxicity in the O. anthropi DE2010 strain. This knowledge may facilitate the successful removal of Cr(III) from the natural environment.

Identificación de Brucella melitensis como Ochrobactrum anthropi mediante MALDI-TOF MS / Identification of Brucella melitensis as Ochrobactrum anthropi by MALDI-TOF MS

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Study on biodegradation kinetics of di-2-ethylhexyl phthalate by newly isolated halotolerant Ochrobactrum anthropi strain L1-W.

OBJECTIVE: Di-2-ethylhexyl phthalate (DEHP) pollution is one of the major environmental concerns all over the world. This research aimed at studying the biodegradation kinetics of DEHP by a newly isolated bacterial strain. Water and sediment samples were collected from Wuhan South Lake and potent bacterial isolates were screened for DEHP degradation, characterized by biochemical, physiological, morphological and 16S rDNA gene sequencing, and optimized under suitable pH, temperature, NaCl and DEHP concentrations. DEHP and its metabolites were quantified by High Performance Liquid Chromatography and their degradation kinetics were studied. RESULTS: The newly isolated bacterium was identified as Ochrobactrum anthropi strain L1-W with 99.63% similarity to Ochrobactrum anthropi ATCC 49188. It was capable of utilizing DEHP as the carbon source. The optimum growth temperature, pH, DEHP and NaCl concentration for the strain L1-W were 30 °C, 6, 400 mg/L and 10 g/L respectively. Strain L1-W was capable of degrading almost all (98.7%) of DEHP when the initial concentration was 200 mg/L within a period of 72 h. Besides, it was also found capable of degrading five other phthalates, thus making it a possible candidate for bioremediation of phthalates in the environmental settings.

Multi-approach analysis to assess the chromium(III) immobilization by Ochrobactrum anthropi DE2010.

Ochrobactrum anthropi DE2010 is a microorganism isolated from Ebro Delta microbial mats and able to resist high doses of chromium(III) due to its capacity to tolerate, absorb and accumulate this metal. The effect of this pollutant on O. anthropi DE2010 has been studied assessing changes in viability and biomass, sorption yields and removal efficiencies. Furthermore, and for the first time, its capacity for immobilizing Cr(III) from culture media was tested by a combination of High Angle Annular Dark Field (HAADF) Scanning Transmission Electron Microscopy (STEM) imaging coupled to Energy Dispersive X-ray spectroscopy (EDX). The results showed that O. anthropi DE2010 was grown optimally at 0-2 mM Cr(III). On the other hand, from 2 to 10 mM Cr(III) microbial plate counts, growth rates, cell viability, and biomass decreased while extracellular polymeric substances (EPS) production increases. Furthermore, this bacterium had a great ability to remove Cr(III) at 10 mM (q = 950.00 mg g-1) immobilizing it mostly in bright polyphosphate inclusions and secondarily on the cellular surface at the EPS level. Based on these results, O. anthropi DE2010 could be considered as a potential agent for bioremediation in Cr(III) contaminated environments.