-
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 -
Ochrobactrum anthropi: An emerging pathogen causing meningitis with sepsis in a neurotrauma patient.Journal of Infection in Developing... Sep 2017Ochrobactrum anthropi is an unusual emerging pathogen especially in the hospital environment. Most of the reported cases are nosocomially acquired infections in...
Ochrobactrum anthropi is an unusual emerging pathogen especially in the hospital environment. Most of the reported cases are nosocomially acquired infections in patients with various indwelling and invasive medical devices, such as central venous catheters and drainage tubes. We report a case of nosocomially transmitted invasive catheter related septicaemia with meningitis due to O. anthropi, in an elderly immunocompetent male with a head trauma admitted to a level -1 trauma centre. This report describes clinical and microbiological characteristics of rare pathogen and also highlights the importance of rapid identification, susceptibility testing of such opportunistic pathogens in trauma settings and its unique antibiotic susceptibility profiles. This requires prompt treatment with timely intervention, and appropriate antimicrobial therapy, alongside adherence to strict infection control practices.
PubMed: 31600165
DOI: 10.3855/jidc.9146 -
Emerging Infectious Diseases Aug 2016We report an outbreak of healthcare-associated prostatitis involving rare environmental pathogens in immunocompetent patients undergoing transrectal prostate biopsies at...
We report an outbreak of healthcare-associated prostatitis involving rare environmental pathogens in immunocompetent patients undergoing transrectal prostate biopsies at Hôpital Édouard Herriot (Lyon, France) during August 13-October 10, 2014. Despite a fluoroquinolone-based prophylaxis, 5 patients were infected with Achromobacter xylosoxidans and 3 with Ochrobactrum anthropi, which has not been reported as pathogenic in nonimmunocompromised persons. All patients recovered fully. Analysis of the outbreak included case investigation, case-control study, biopsy procedure review, microbiologic testing of environmental and clinical samples, and retrospective review of hospital records for 4 years before the outbreak. The cases resulted from asepsis errors during preparation of materials for the biopsies. A low-level outbreak involving environmental bacteria was likely present for years, masked by antimicrobial drug prophylaxis and a low number of cases. Healthcare personnel should promptly report unusual pathogens in immunocompetent patients to infection control units, and guidelines should explicitly mention asepsis during materials preparation.
Topics: Achromobacter denitrificans; Biopsy; Case-Control Studies; Disease Outbreaks; Equipment Contamination; France; Gram-Negative Bacterial Infections; Humans; Male; Ochrobactrum anthropi; Prostatic Diseases; Surgical Equipment
PubMed: 27434277
DOI: 10.3201/eid2208.151423 -
Journal of Applied Microbiology Aug 2009To evaluate Ochrobactrum anthropi TRS-2 isolated from tea rhizosphere and its talc based formulation for growth promotion and management of brown root rot disease of tea.
AIM
To evaluate Ochrobactrum anthropi TRS-2 isolated from tea rhizosphere and its talc based formulation for growth promotion and management of brown root rot disease of tea.
METHODS AND RESULTS
Ochrobactrum anthropi TRS-2, isolated from tea rhizosphere could solubilize phosphate, produce siderophore and IAA in vitro and also exhibited antifungal activity against six test pathogens. Application of an aqueous suspension of O. anthropi to the rhizosphere of nursery grown tea seedlings of five varieties of tea (TV-18, T-17, HV-39, S-449, UP-3 and) led to enhanced growth of the treated plants, as evidenced by increase in height, in the number of shoots and number of leaves per shoot. Treatment with O. anthropi also decreased brown root rot of tea, caused by Phellinus noxius. Multifold increase in activities of chitinase, beta-1,3-glucanase, peroxidase and phenylalanine ammonia lyase in tea plants was observed on application of O. anthropi to soil followed by inoculation with P. noxius. A concomitant increase in accumulation of phenolics was also obtained. Further, talc based formulation of O. anthropi was prepared and its survival determined every month up to a period of 12 months. Ochrobactrum anthropi could survive in the formulation up to a period of 9 months with a concentration of 7.0 log(10) CFU g(-1), after which there was a decline. Talc formulation was as effective as aqueous suspensions in both plant growth promotion and disease suppression.
CONCLUSION
Ochrobactrum anthropi, either in aqueous suspension or as talc formulation induced growth of tea plants and suppressed brown root rot disease. It induced defense responses in tea plants.
SIGNIFICANCE AND IMPACT OF THE STUDY
Ochrobactrum anthropi and its talc based formulation can be considered as an addition to available plant growth promoting rhizobacteria (PGPR) currently being used for field application. The present study offers a scope of utilizing this bacterium for growth promotion and disease management which would help in reduction of the use of chemicals in tea plantations.
Topics: Antifungal Agents; Basidiomycota; Camellia sinensis; Chitinases; Colony Count, Microbial; Glucan 1,3-beta-Glucosidase; Ochrobactrum anthropi; Peroxidase; Phenols; Phenylalanine Ammonia-Lyase; Plant Diseases
PubMed: 19426277
DOI: 10.1111/j.1365-2672.2009.04242.x -
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 -
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 Clinical Microbiology Jun 2018
Closing the Brief Case: Misidentification of Brucella melitensis as Ochrobactrum anthropi by Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS).
Topics: Brucella melitensis; Ochrobactrum anthropi; Polymerase Chain Reaction; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
PubMed: 29802239
DOI: 10.1128/JCM.00918-17 -
Heart & Lung : the Journal of Critical... 1999Ochrobactrum Anthropi (O. anthropi ), formerly known as Achromobacter CDC group Vd, is a gram-negative bacillus that is aerobic, oxidase producing, and nonlactose...
Ochrobactrum Anthropi (O. anthropi ), formerly known as Achromobacter CDC group Vd, is a gram-negative bacillus that is aerobic, oxidase producing, and nonlactose fermenting. This organism has been found in environmental and hospital water sources and has pathogenic potential in humans. Most reports in the literature of O. anthropi bacteremia are associated with intravenous line infections. We describe a case of bacteremia with O. anthropi in a 33-month-old boy with acute osteomyelitis. O. anthropi bacteremia also has been reported in immunocompromised hosts. Rarely, O. anthropi has been a cause of soft tissue or bone infection.
Topics: Alcaligenes; Bacteremia; Bacteriological Techniques; Child, Preschool; Femur; Gram-Negative Bacterial Infections; Humans; Male; Microbial Sensitivity Tests; Osteomyelitis; Virulence
PubMed: 10076115
DOI: 10.1053/hl.1999.v28.a94602 -
Journal of Infection and Public Health 2018Ochrobactrum anthropi has become an emerging pathogen for bloodstream infection (BSI).
BACKGROUND
Ochrobactrum anthropi has become an emerging pathogen for bloodstream infection (BSI).
METHODS
From January 1st 2010 to June 30th 2017, inpatients with one or more blood cultures positive for O. anthropi isolates at Chinese People's Liberation Army General Hospital in Beijing, China, were enrolled in this study. Clinical and laboratory data were collected by reviewing electronic records.
RESULTS
A total of 11 patients with O. anthropi BSI were identified, of which 10 patients survived. There were 6 males and 5 females, whose age ranged from 2 to 83 years. 7 infections were hospital-acquired. In 8 cases O. anthropi was the only pathogen. The most common symptoms of O. anthropi BSI were fever (100%) and disorders of consciousness (45.5%). All patients had undergone indwelling catheter placement. O. anthropi isolates in this study were most susceptible to levofloxacin (100%), ciprofloxacin (85.7%), imipenem (85.7%) and cotrimoxazole (85.7%), while they were widely resistant to penicillins and cephalosporins.
CONCLUSIONS
O. anthropi BSI usually happens in patients with indwelling catheters, and often begins with no distinctive symptom or laboratory finding. O. anthropi seldom form polymicrobial BSIs. Quinolones and carbapenems are optimal antibiotics for O. anthropi BSI. Catheter removal is essential when O. anthropi BSI happens recurrently.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Anti-Bacterial Agents; Catheter-Related Infections; Child; Child, Preschool; China; Cross Infection; Female; Gram-Negative Bacterial Infections; Humans; Male; Microbial Sensitivity Tests; Middle Aged; Ochrobactrum anthropi; Sepsis; Survival Analysis; Tertiary Care Centers; Young Adult
PubMed: 30100242
DOI: 10.1016/j.jiph.2018.07.009