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Journal of Global Antimicrobial... Jun 2022To explore the genomic characterization of an IMP-8-producing Ochrobactrum anthropic and give suggestions for the application of antibiotics.
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.
Topics: Anti-Bacterial Agents; Carbapenems; Ceftazidime; Gold Colloid; Humans; Meropenem; Microbial Sensitivity Tests; Ochrobactrum anthropi; beta-Lactamases
PubMed: 35346886
DOI: 10.1016/j.jgar.2022.03.016 -
Journal of Hand Surgery Global Online Nov 2020is an opportunistic, low-virulence pathogen occasionally associated with human infections and found largely in immunocompromised patients and those with intravascular...
is an opportunistic, low-virulence pathogen occasionally associated with human infections and found largely in immunocompromised patients and those with intravascular devices. We report the case of a healthy 70-year-old man who presented with an infection of the hand, who had no history of trauma but had been gardening for 4 months. Despite surgical debridement and empirical antibiotics, the infection could not be controlled. Cultures revealed . Antibiotic treatment was adapted to intravenous cefepime for 15 days and the infection was finally controlled after a second surgery. Oral cotrimoxazole was continued for another 2 weeks. infection of the hand must be considered not only in immunosuppressed patients but also in healthy patients without intravascular devices. Local debridement and empiric antibiotic may be insufficient. Antibiotic therapy should follow susceptibility testing, but usually includes a broad-spectrum intravenous beta-lactam such as imipenem-cilastatin or cefepime, or oral cotrimoxazole or ciprofloxacin.
PubMed: 35415523
DOI: 10.1016/j.jhsg.2020.08.006 -
Journal of Orthopaedic Case Reports Mar 2022Ochrobactrum anthropi is an opportunistic and rare human pathogen, which is seen widely in the environment. O. anthropi infections have been reported in both...
INTRODUCTION
Ochrobactrum anthropi is an opportunistic and rare human pathogen, which is seen widely in the environment. O. anthropi infections have been reported in both immunocompetent and immunocompromised individuals. There is no proper consensus on the diagnosis and management of O. anthropi related infections.
CASE REPORT
We report a case of O. anthropi related left distal clavicular osteomyelitis in an immunocompetent individual with an elaborative diagnostic and treatment algorithm for its effective management.
CONCLUSION
A comprehensive management strategy with a combination of implant removal (if present) with extensive surgical debridement of bone and soft tissue and intravenous antibiotics results in successful eradication of O. anthropi infection.
PubMed: 36199934
DOI: 10.13107/jocr.2022.v12.i03.2730 -
Microorganisms Apr 2020Azoxystrobin is one of the most popular strobilurin fungicides, widely used in agricultural fields for decades.Extensive use of azoxystrobin poses a major threat to...
Azoxystrobin is one of the most popular strobilurin fungicides, widely used in agricultural fields for decades.Extensive use of azoxystrobin poses a major threat to ecosystems. However, little is known about the kinetics and mechanism of azoxystrobin biodegradation. The present study reports a newly isolated bacterial strain, SH14, utilizing azoxystrobin as a sole carbon source, was isolated from contaminated soils. Strain SH14 degraded 86.3% of azoxystrobin (50 μg·mL) in a mineral salt medium within five days. Maximum specific degradation rate (), half-saturation constant (), and inhibition constant () were noted as 0.6122 d, 6.8291 μg·mL, and 188.4680 μg·mL, respectively.Conditions for strain SH14 based azoxystrobin degradation were optimized by response surface methodology. Optimum degradation was determined to be 30.2 °C, pH 7.9, and 1.1 × 10 CFU·mL of inoculum. Strain SH14 degraded azoxystrobin via a novel metabolic pathway with the formation of -(4,6-dimethoxypyrimidin-2-yl)-acetamide,2-amino-4-(4-chlorophenyl)-3-cyano-5,6-dimethyl-pyridine, and 3-quinolinecarboxylic acid,6,8-difluoro-4-hydroxy-ethyl ester as the main intermediate products, which were further transformed without any persistent accumulative product. This is the first report of azoxystrobin degradation pathway in a microorganism. Strain SH14 also degraded other strobilurin fungicides, including kresoxim-methyl (89.4%), pyraclostrobin (88.5%), trifloxystrobin (78.7%), picoxystrobin (76.6%), and fluoxastrobin (57.2%) by following first-order kinetic model. Bioaugmentation of azoxystrobin-contaminated soils with strain SH14 remarkably enhanced the degradation of azoxystrobin, and its half-life was substantially reduced by 95.7 and 65.6 days in sterile and non-sterile soils, respectively, in comparison with the controls without strain SH14. The study presents SH14 for enhanced biodegradation of azoxystrobin and elaborates on the metabolic pathways to eliminate its residual toxicity from the environment.
PubMed: 32357564
DOI: 10.3390/microorganisms8050625 -
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 -
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 Research Notes May 2020Di-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...
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.
Topics: Biodegradation, Environmental; China; Chromatography, High Pressure Liquid; Diethylhexyl Phthalate; Humans; Hydrogen-Ion Concentration; Kinetics; Ochrobactrum anthropi; Phylogeny; RNA, Ribosomal, 16S; Soil; Temperature
PubMed: 32448295
DOI: 10.1186/s13104-020-05096-0 -
Carbohydrate Polymers Oct 2023Lipopolysaccharides (LPS) are major players in bacterial infection through the recognition by Toll-like receptor 4 (TLR4). The LPS chemical structure, including the...
Lipopolysaccharides (LPS) are major players in bacterial infection through the recognition by Toll-like receptor 4 (TLR4). The LPS chemical structure, including the oligosaccharide core and the lipid A moiety, can be strongly influenced by adaptation and modulated to assure bacteria protection, evade immune surveillance, or reduce host immune responses. Deep structural understanding of TLRs signaling is essential for the modulation of the innate immune system in sepsis control and inflammation, during bacterial infection. To advance this knowledge, we have employed computational techniques to characterize the TLR4 molecular recognition of atypical LPSs from different opportunistic members of α2-Proteobacteria, including Brucella melitensis, Ochrobactrum anthropi, and Ochrobactrum intermedium, with diverse immunostimulatory activities. We contribute to unraveling the role of uncommon lipid A chemical features such as bearing very long-chain fatty acid chains, whose presence has been rarely reported, on modulating the proper heterodimerization of the TLR4 receptor complex. Moreover, we further evaluated the influence of the different oligosaccharide cores, including sugar composition and net charge, on TLR4 activation. Our studies contribute to elucidating, from the molecular and biological perspectives, the impact of the α2-Proteobacteria LPS cores and the chemical structure of the atypical lipid A for immune system evasion in opportunistic bacteria.
Topics: Humans; Lipopolysaccharides; Toll-Like Receptor 4; Lipid A; Proteobacteria; Immune Evasion; Bacteria; Bacterial Infections; Oligosaccharides
PubMed: 37479429
DOI: 10.1016/j.carbpol.2023.121094 -
Journal of Laboratory Physicians Mar 2023, due to its robust survival abilities, has been known to cause nosocomial and opportunistic infections, posing both diagnostic and therapeutic challenges. Low...
, due to its robust survival abilities, has been known to cause nosocomial and opportunistic infections, posing both diagnostic and therapeutic challenges. Low virulence, indolent clinical presentation, and lack of awareness on their clinical significance attribute to the underreporting of the same. We report two cases of bacteremia in oncology patients presented to us in a short span of 6 months, which indicates that such infections might be quite common in immunocompromised hosts. Both our strains were susceptible to carbapenems, trimethoprim/sulfamethoxazole, and minocycline, and recovered with monotherapy. More vigilant and accurate diagnostic techniques need to be followed not to miss such pathogens. Early identification and administration of appropriate antibiotics have been associated with a good outcome.
PubMed: 37064972
DOI: 10.1055/s-0042-1757235 -
Genomics Sep 2020Ochrobactrum genus is comprised of soil-dwelling Gram-negative bacteria mainly reported for bioremediation of toxic compounds. Since last few years, mainly two species...
Ochrobactrum genus is comprised of soil-dwelling Gram-negative bacteria mainly reported for bioremediation of toxic compounds. Since last few years, mainly two species of this genus, O. intermedium and O. anthropi were documented for causing infections mostly in the immunocompromised patients. Despite such ubiquitous presence, study of adaptation in various niches is still lacking. Thus, to gain insights into the niche adaptation strategies, pan-genome analysis was carried out by comparing 67 genome sequences belonging to Ochrobactrum species. Pan-genome analysis revealed it is an open pan-genome indicative of the continuously evolving nature of the genus. The presence/absence of gene clusters also illustrated the unique presence of antibiotic efflux transporter genes and type IV secretion system genes in the clinical strains while the genes of solvent resistance and exporter pumps in the environmental strains. A phylogenomic investigation based on 75 core genes depicted better and robust phylogenetic resolution and topology than the 16S rRNA gene. To support the pan-genome analysis, individual genomes were also investigated for the mobile genetic elements (MGE), antibiotic resistance genes (ARG), metal resistance genes (MRG) and virulence factors (VF). The analysis revealed the presence of MGE, ARG, and MRG in all the strains which play an important role in the species evolution which is in agreement with the pan-genome analysis. The average nucleotide identity (ANI) based on the genetic relatedness between the Ochrobactrum species indicated a distinction between individual species. Interestingly, the ANI tool was able to classify the Ochrobactrum genomes to the species level which were assigned till the genus level on the NCBI database.
Topics: Drug Resistance, Bacterial; Environmental Microbiology; Genes, Bacterial; Genome, Bacterial; Genomics; Humans; Interspersed Repetitive Sequences; Molecular Sequence Annotation; Ochrobactrum; Phylogeny; Virulence Factors
PubMed: 32428556
DOI: 10.1016/j.ygeno.2020.04.030