Ochrobactrum Anthropi Research Articles

ISOLATION, IDENTIFICATION AND PHYLOGENETIC CHARACTERIZATION OF POTASSIUM-SOLUBILIZING RHIZOBACTERIA ISOLATED FROM THE ROOTS OF Mimosa indica WEED

Most microorganisms residing within plant rhizosphere are of great importance to soil fertility. The either release plant nutrient into soil solution and make it available for plant absorption directly or indirectly, excrete enzymes or organic acids that facilitate the solubilization of insoluble minerals, such as potassium (K). A laboratory analysis was carried out at the Soil Science Laboratory in Michael Okpara University of Agriculture, Umudike, to isolate potassium-solubilizing rhizobacteria from Mimosa indica a weed that have invaded most agricultural land in the southeastern Nigeria. It was observed that the roots of Mimosaindica had nodules, which is peculiar to legume plants. Two cultivable isolates possessed the ability to solubilize K. DNA extraction was done and the two bacteria were identified as: Ochrobactrum anthropi and Comamonas testosteroni. Biochemical tests and Phylogenetic characterization were carried out. Comamonas testosterone gave the highest solubilization efficiency of 650 compared to Ochrobactrum anthropi (325).

Synergistic improvement of cinnamylamine production by metabolic regulation

BackgroundAromatic primary amines (APAs) are key intermediates in the chemical industry with numerous applications. Efficient and mild biocatalytic synthesis is an excellent complement to traditional chemical synthesis. Our lab previously reported a whole-cell catalytic system for the synthesis of APAs catalyzed by carboxylic acid reductase from Neurospora crassa (ncCAR) and ω-transaminase from Ochrobactrum anthropi (OATA). However, the accumulation of toxic intermediates (aromatic aldehydes) during biocatalytic synthesis affected yields of APAs due to metabolic imbalance.ResultsIn this work, the biocatalytic synthesis of APAs (taking cinnamylamine as an example) was metabolically regulated by the overexpression or knockout of five native global transcription factors (TFs), the overexpression of eight native resistance genes, and optimization of promoters. Transcriptome analysis showed that knockout of the TF arcA increased the fluxes of NADPH and ATP in E. coli, while the rate of pyruvate metabolism was accelerated. In addition, the genes related to stress and detoxification were upregulated with the overexpression of resistance gene marA, which reduced the NADPH level in E. coli. Then, the expression level of soluble OATA increased by promoter optimization. Overall, arcA and marA could regulate the catalytic rate of NADPH- dependent ncCAR, while arcA and optimized promoter could regulate the catalytic rate of OATA. Lastly, the cinnamylamine yield of the best metabolically engineered strain S020 was increased to 90% (9 mM, 1.2 g/L), and the accumulation of cinnamaldehyde was below 0.9 mM. This work reported the highest production of cinnamylamine by biocatalytic synthesis.ConclusionThis regulatory process provides a common strategy for regulating the biocatalytic synthesis of other APAs. Being entirely biocatalytic, our one-pot procedure provides considerable advantages in terms of environmental and safety impacts over reported chemical methods.

Exploration study of indigenous civet (Paradoxorus hermaphroditus) bacteria: isolates characterization and molecular identification

Biochemistry of civet coffee fermentation in the digestive tract of civets until now is not fully known. This study aims to isolation, characterization and identification of bacteria molecularly from the civet's digestive tract. Analysis of bacteria begins with the civet surgery to obtain fluid from three parts of the civet's digestive tract. Isolation of bacteria conducted by pour plate method using nutrient agar media. Single and different colonies (shape, colour, margin, elevation, size) were separated and purified by streaking method. The pure isolate was further characterized biochemically. The biochemical characteristics of the bacteria observed were Gram staining, catalase, protease and pectinase activity. Identification of the bacteria was carried out molecularly by identifying the 16S rRNA gene. The results of molecular identification showed that the bacteria from the civet were identified as Alcaligenes faecalis strain LHW 1749, Ochrobactrum anthropi, Stenotrophomonas sp. 262 and Bacillus sp.

Ochrobactrum anthropi: An Unusual Emerging Pathogen

Ochrobactrum anthropi is an organism which is commonly distributed in the environment and water sources including normal saline, antiseptic solutions, and dialysis fluid. However, it is an opportunistic pathogen, especially in critically ill or immunocompromised patients. The presence of central venous catheter line is a risk factor. Here, we report two cases of bacteremia caused by O. anthropi in patients undergoing chemotherapy.

Meningitis due to Ochrobactrum anthropi an Emerging Pathogen

Meningitis due to Ochrobactrum anthropi an Emerging Pathogen

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.

Natural association of the entomopathogenic nematode Heterorhabditis indica (Rhabditida: Heterorhabditidae) from the Philippines with the non-symbiotic bacterium Ochrobactrum anthropi (Proteobacteria: Brucellaceae)

BackgroundEntomopathogenic nematodes of the genera Heterorhabditis and Steinernema are widely used as biocontrol agents against diverse insect pests. Their association with symbiont bacteria is found to be the primary cause of insect mortality. The present study reported a comprehensive characterization of a local Philippine EPN isolate using congruent morpho-taxometrical and molecular data and the associated bacterium in the infective dauer juveniles.ResultsUsing an insect-baiting technique, a nematode isolate labeled F2H was recovered from the sandy soils in the coastal area of southern Philippines. Based on morphology and morpho-taxometrics, the F2H isolate collected from Iligan City was identified as Heterorhabditis indica. Analysis of the ITS region of rDNA revealed the highest sequence match to H. indica. The sequences of the bacterial 16S rDNA gene showed that the symbiont of H. indica presented 100% similitude with the sequences of Ochrobactrum anthropi. Further, pairwise alignment and phylogenetic analysis demonstrated that O. anthropi, O. lupini and O. cytisi shared 100% similarity and form a monophyletic clade. These strains have not presented any differences in the phylogenetic and 16S rDNA data, and O. lupini and O. cytisi should be considered a later heterotypic synonym of O. anthropi.ConclusionsThe description of H. indica-O. anthropi association was the first report in the Philippines. This provides additional account and collection of naturally isolated EPN-bacteria, contributing to limited knowledge on its diversity in the Philippines, which can be utilized in the biocontrol of pests after further comprehensive assessments.

Self-sufficient whole-cell biocatalysis for 3-(aminomethyl) pyridine synthesis

3-(Aminomethyl) pyridine (3-AMP) is a versatile compound for the synthesis of pharmaceuticals, agricultural chemicals and numerous polymers. Efficient and mild biocatalytic synthesis is often an excellent supplement to traditional chemical synthesis methods. However, there has been no report of biocatalytic 3-AMP synthesis. In this paper, 3-AMP was synthesized for the first time by using biocatalysts co-expressing carboxylic acid reductase from Neurospora crassa (ncCAR) and ω-transaminase from Ochrobactrum anthropi (OATA) in one pot. In addition, the metabolic pathway was optimized by knocking out the transcriptional dual regulator arcA, which resulted in a 90% increase in the yield of 3-AMP. Furthermore, efficient self-sufficient whole-cell bioconversion was established by optimization, achieving 93% yield and a 40.6 mM (4.4 g/L) titer of 3-AMP without additional carbon sources. This whole-cell bioconversion system was also suitable for the high-efficiency biocatalytic synthesis of other aromatic or heterocyclic primary amines, such as benzylamine, 2-furfurylamine, 4-fluorobenzylamine, 2,4-difluorobenzylamine and 2-(aminomethyl) pyridine.Being entirely biocatalytic, our one-pot procedure provides considerable advantages in terms of economic, environmental and safety impacts over reported chemical methods.

First report of Ochrobactrum anthropi isolated from bloodstream infection in Alexandria, Egypt

First report of Ochrobactrum anthropi isolated from bloodstream infection in Alexandria, Egypt

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

To explore the genomic characterization of an IMP-8-producing Ochrobactrum anthropic and give suggestions for the application of antibiotics. 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. 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. Improper antibiotic treatment can cause intestinal flora imbalance and even bacteremia in patients, we should use antibiotics wisely and develop individualized treatment options.

English

Fifteen fungal and three bacterial biological control agents (F-BCA and B-BCA, respectively) were isolated from the canola production areas of Western Australia to investigate their potential for controlling sclerotinia stem rot (SSR) caused by Sclerotinia sclerotiorum under in vitro and field conditions. The capacity of these isolates to inhibit mycelial growth and sclerotia formation by S. sclerotiorum was assessed in dual culture tests in Petri dishes. Using Sanger Sequencing of the ITS regions, the F-BCAs were identified as Trichoderma atroviride (four isolates), T. gamsii (three isolates), T. koningiopsis (two isolates), T. longibrachiatum (two isolates), T. paraviridescens (two isolates), T. pseudokoningii (one isolate) and T. viridescens (one isolate). Four of the seven Trichoderma species (T. koningiopsis, T. gamsii, T. atroviride and T. viridescens) are reported for the first time from Western Australia. 16S rRNA sequencing identified B-BCA1 and B-BCA2 as Serratia proteamaculans and B-BCA3 as Ochrobactrum anthropi. There were significant differences among F-BCAs (P≤0.001) in their effect on radial mycelial growth (40–60% inhibition) and sclerotia formation (65–100% inhibition). Two isolates of T. atroviride (F-BCA12 and F-BCA15) completely blocked sclerotial formation of the pathogen on Potato dextrose agar + 10 ppm/L Aureomycin (PDAA). Incubation of sclerotia in soil inoculated with F-BCA indicated that sclerotia were colonized by the conidia of each F-BCA, and all sclerotia in the presence of F-BCAs failed to germinate on PDAA. The B-BCAs reduced radial mycelial growth by 57–59% and formation of sclerotia by 89–95%. Selected isolates of F-BCAs (T. koningiopsis and T. atroviride) and B-BCAs (O. anthropi and S. proteamaculans) significantly reduced disease incidence of S. sclerotiorum under glasshouse and field conditions. Field efficacy of tested BCAs was similar or better than the commercial fungicide Prosaro®. © 2022 Friends Science Publishers

Micrococcin P1 and P2 from Epibiotic Bacteria Associated with Isolates of Moorea producens from Kenya.

Epibiotic bacteria associated with the filamentous marine cyanobacterium Moorea producens were explored as a novel source of antibiotics and to establish whether they can produce cyclodepsipeptides on their own. Here, we report the isolation of micrococcin P1 (1) (C48H49N13O9S6; obs. m/z 1144.21930/572.60381) and micrococcin P2 (2) (C48H47N13O9S6; obs. m/z 1142.20446/571.60370) from a strain of Bacillus marisflavi isolated from M. producens’ filaments. Interestingly, most bacteria isolated from M. producens’ filaments were found to be human pathogens. Stalked diatoms on the filaments suggested a possible terrestrial origin of some epibionts. CuSO4·5H2O assisted differential genomic DNA isolation and phylogenetic analysis showed that a Kenyan strain of M. producens differed from L. majuscula strain CCAP 1446/4 and L. majuscula clones. Organic extracts of the epibiotic bacteria Pseudoalteromonas carrageenovora and Ochrobactrum anthropi did not produce cyclodepsipeptides. Further characterization of 24 Firmicutes strains from M. producens identified extracts of B. marisflavi as most active. Our results showed that the genetic basis for synthesizing micrococcin P1 (1), discovered in Bacillus cereus ATCC 14579, is species/strain-dependent and this reinforces the need for molecular identification of M. producens species worldwide and their epibionts. These findings indicate that M. producens-associated bacteria are an overlooked source of antimicrobial compounds.

39P Cancers with Ochrobactrum anthropi infection show enhanced responses to immune checkpoint blockade treatment

Accumulating clinical evidence has shown that different kinds of microbiota are involved in various cancers and their DNA levels are correlated with metastasis and prognosis. Ochrobactrum anthropi is an emerging opportunistic pathogen in patients with immunocompromised function. The effect of O. anthropi infection on the survival of patients with cancer is not clear.

Characteristics in gut microbiome is associated with chemotherapy-induced pneumonia in pediatric acute lymphoblastic leukemia

BackgroundChildren 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.MethodsWe 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.ResultsThere 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.ConclusionsGut 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.

Brucellosis Initially Misidentified as Ochrobactrum anthropi Bacteremia: A Case Report and Review of the Literature.

Automated identification systems may misidentify Brucella, 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 Brucella suis likely associated with feral swine exposure that was misidentified as Ochrobactrum anthropi, a phylogenetic relative.

Active-site engineering of \u03c9-transaminase from Ochrobactrum anthropi for preparation of L-2-aminobutyric acid

BackgroundThe 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.ResultsBased 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.ConclusionThis study provides a basis for further engineering of ω-transaminase for producing chiral amines from keto acids substrates.

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 β-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.

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.

Acute endophthalmitis caused by Ochrobactrum anthropi following cataract surgery in an immunocompetent patient – A case report

A 54-year-old man developed left eye inflammation three days after cataract surgery and was diagnosed with endophthalmitis. Aqueous culture revealed Ochrobactrum anthropi resistant to vancomycin and cephalosporin. Systemic and intravitreal ciprofloxacin injections caused only transient improvement and eventually, pars plana vitrectomy was done. There was complete resolution, good visual recovery, and no recurrence. O.anthropi is an uncommon organism with a characteristic resistance to empirical antibiotics and usually causes chronic infection in immunocompromised. We report a rare case of acute endophthalmitis in an immunocompetent patient. To the best of our knowledge, this is the first report of O. anthropi endophthalmitis from India.

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

ABSTRACT 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.