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BMC Infectious Diseases Dec 2023Pseudomonas otitidis belongs to the genus Pseudomonas and causes various infections, including ear, skin, and soft tissue infections. P. otitidis has a unique... (Review)
Review
BACKGROUND
Pseudomonas otitidis belongs to the genus Pseudomonas and causes various infections, including ear, skin, and soft tissue infections. P. otitidis has a unique susceptibility profile, being susceptible to penicillins and cephalosporins but resistant to carbapenems, due to the production of the metallo-β-lactamase called POM-1. This revealed genetic similarities with Pseudomonas aeruginosa, which can sometimes lead to misidentification.
CASE PRESENTATION
We report the case of a 70-year-old Japanese male who developed cellulitis and bacteremia during chemotherapy for multiple myeloma. He was initially treated with meropenem, but blood culture later revealed gram-negative bacilli identified as P. otitidis using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). Carbapenem resistance was predicted from previous reports; therefore, we switched to dual therapy with levofloxacin and cefepime, and favorable treatment results were obtained.
CONCLUSION
This is the first reported case of P. otitidis cellulitis and bacteremia in an immunocompromised patient. Carbapenems are typically used in immunocompromised patients and P. otitidis is often resistant to it. However, its biochemical properties are similar to those of Pseudomonas aeruginosa; therefore, its accurate identification is critical. In the present study, we rapidly identified P. otitidis using MALDI-TOF MS and switched from carbapenems to an appropriate antimicrobial therapy, resulting in a successful outcome.
Topics: Humans; Male; Aged; Anti-Bacterial Agents; Cellulitis; Pseudomonas; Carbapenems; Pseudomonas Infections; Pseudomonas aeruginosa; Bacteremia; Immunocompromised Host; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
PubMed: 38110897
DOI: 10.1186/s12879-023-08919-0 -
Letters in Applied Microbiology Jun 2024This study explores the eco-friendly synthesis of silver nanoparticles (AgNPs) using soil bacteria, Pseudomonas otitidis. The bio-synthesized AgNPs were characterized...
This study explores the eco-friendly synthesis of silver nanoparticles (AgNPs) using soil bacteria, Pseudomonas otitidis. The bio-synthesized AgNPs were characterized using various techniques, including UV-visible spectroscopy, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and X-ray diffraction (XRD). UV-visible spectroscopy revealed a distinct broad absorption band in the range of 443 nm, indicating the reduction of silver nitrate to AgNPs. XRD analysis provided evidence of the crystalline nature of the particles, with sharp peaks confirming their crystallinity and an average size of 82.76 nm. FTIR spectroscopy identified extracellular protein compounds as capping agents. SEM examination revealed spherical agglomeration of the crystalline AgNPs. The antimicrobial assay by a disc diffusion method, minimum inhibitory concentration, and minimum bactericidal concentration testing revealed that the biosynthesized AgNPs showed moderate antibacterial activity against both pathogenic Gram-negative (Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii) and Gram-positive (Bacillus cereus, Staphylococcus aureus, and Streptococcus mutans) bacterial strains. Furthermore, the AgNPs significantly disrupted the biofilm of P. aeruginosa, as confirmed by crystal violet assay and fluorescent microscopy. Overall, this study underscores the potential of microbial-synthesized nanoparticles in biomedical applications, particularly in combating pathogenic bacteria, offering a promising avenue for future research and development.
Topics: Silver; Biofilms; Metal Nanoparticles; Anti-Bacterial Agents; Microbial Sensitivity Tests; Pseudomonas; Spectroscopy, Fourier Transform Infrared; X-Ray Diffraction; Pseudomonas aeruginosa
PubMed: 38845375
DOI: 10.1093/lambio/ovae053 -
BMC Infectious Diseases Aug 2021Pseudomonas otitidis is a novel species of Pseudomonas bacteria that has been isolated from patients with otic infections. (Review)
Review
BACKGROUND
Pseudomonas otitidis is a novel species of Pseudomonas bacteria that has been isolated from patients with otic infections.
CASE PRESENTATION
In this report, we describe a case of a 59-year-old known with moderate chronic obstructive pulmonary disease with bronchiectasis and recurrent pneumonia where blood cultures revealed the growth of P. otitidis.
CONCLUSIONS
This case describes the first report of bacteraemia to P. otitidis and raises questions regarding the misdiagnosis and underestimation of the incidence of infections caused by this novel pathogen.
Topics: Bacteremia; Humans; Middle Aged; Pneumonia; Pseudomonas; Pulmonary Disease, Chronic Obstructive
PubMed: 34433417
DOI: 10.1186/s12879-021-06569-8 -
Archives of Microbiology Jul 2020L-asparaginase (E.C.3.5.1.1) is an important enzyme that has been purified and characterized for over decades to study and evaluate its anti-carcinogenic activity... (Review)
Review
L-asparaginase (E.C.3.5.1.1) is an important enzyme that has been purified and characterized for over decades to study and evaluate its anti-carcinogenic activity against different lymphoproliferative disorders such as acute lymphoblastic leukemia (ALL) and Hodgkin's lymphoma. The ability of the enzyme to convert L-asparagine into aspartic acid and ammonia is the reason behind its anti-cancerous activity. Apart from its medicinal uses, it is widely used in food industry to tackle acrylamide, a probable human carcinogen and, production in carbohydrate-rich foods cooked at high temperatures. There are variety of organisms including microorganisms such as bacteria, fungi, algae, and plants that produce L-asparaginase. The enzyme obtained from different microbial and plant sources have different physiochemical properties and kinetic parameters. L-asparaginases have an optimum pH range between 6 and 10 and an optimum temperature between 37 and 85 °C. This article has reviewed the lowest molecular mass for L-asparaginase in Yersinia pseudotuberculosis Q66CJ2 which is 36.27 kDa, while the highest for Pseudomonas otitidis which has a molecular mass of 205 ± 3 kDa. This review is an attempt to summarize most of the available sources, their phylogenetic relationships, purification methods, data regarding different physiochemical and kinetic properties of L-asparaginase.
Topics: Ammonia; Asparaginase; Asparagine; Aspartic Acid; Bacteria; Fungi; Hodgkin Disease; Humans; Phylogeny; Plants; Precursor Cell Lymphoblastic Leukemia-Lymphoma
PubMed: 32052094
DOI: 10.1007/s00203-020-01814-1 -
Frontiers in Microbiology 2020Anthropogenic perturbations introduce novel selective pressures to natural environments, impacting the genomic variability of organisms and thus altering the...
Anthropogenic perturbations introduce novel selective pressures to natural environments, impacting the genomic variability of organisms and thus altering the evolutionary trajectory of populations. Water overexploitation for agricultural purposes and defective policies in Cuatro Cienegas, Coahuila, Mexico, have strongly impacted its water reservoir, pushing entire hydrological systems to the brink of extinction along with their native populations. Here, we studied the effects of continuous water overexploitation on an environmental aquatic lineage of over a 13-year period which encompasses three desiccation events. By comparing the genomes of a population sample from 2003 (original state) and 2015 (perturbed state), we analyzed the demographic history and evolutionary response to perturbation of this lineage. Through coalescent simulations, we obtained a demographic model of contraction-expansion-contraction which points to the occurrence of an evolutionary rescue event. Loss of genomic and nucleotide variation alongside an increment in mean and variance of Tajima's , characteristic of sudden population expansions, support this observation. In addition, a significant increase in recombination rate (R/θ) was observed, pointing to horizontal gene transfer playing a role in population recovery. Furthermore, the gain of phosphorylation, DNA recombination, small-molecule metabolism and transport and loss of biosynthetic and regulatory genes suggest a functional shift in response to the environmental perturbation. Despite subsequent sampling events in the studied site, no pseudomonad was found until the lagoon completely dried in 2017. We speculate about the causes of final decline or possible extinction. Overall our results are evidence of adaptive responses at the genomic level of bacterial populations in a heavily exploited aquifer.
PubMed: 33552002
DOI: 10.3389/fmicb.2020.563885 -
The Journal of Antimicrobial... Aug 2022There is no comprehensive study on PAM-like MBLs.
BACKGROUND
There is no comprehensive study on PAM-like MBLs.
OBJECTIVES
Our aim was to characterize novel B3 MBL variants, PAM-2 and PAM-3, from Pseudomonas tohonis clinical isolates.
METHODS
We evaluated the antimicrobial susceptibility and the MBL gene composition of three novel P. tohonis clinical isolates identified at a Japanese hospital, using the broth microdilution method and WGS, respectively. We characterized the PAM-2 and PAM-3 proteins using recombinant protein expression and biochemical evaluations.
RESULTS
Low carbapenem MICs (meropenem MIC = 0.125-1 mg/L) were observed for all three P. tohonis isolates; however, the isolates produced MBLs. We identified blaPAM-2 and blaPAM-3 as potential genes, belonging to a novel subclass of B3 MBLs. Their genomic sequence was similar to that of blaPAM-1 from Pseudomonas alcaligenes. PAM-2 and PAM-3 comprised 287 amino acids and exhibited 90% amino acid identity with PAM-1, 73% identity with POM-1 from Pseudomonas otitidis and 61% identity with L1 from Stenotrophomonas maltophilia. Biochemical evaluations of recombinant PAM-2 and PAM-3 revealed similar kcat/Km ratios and demonstrated catalytic activity against all the tested β-lactams, except for aztreonam. In addition, the kcat/Km ratio for imipenem was 40-fold lower than that for meropenem.
CONCLUSIONS
P. tohonis harbours a species-specific PAM-family MBL gene. This enzyme has higher hydrolytic activity against meropenem compared with that against imipenem.
Topics: Anti-Bacterial Agents; Humans; Imipenem; Meropenem; Microbial Sensitivity Tests; Pseudomonas; Pseudomonas Infections; Pseudomonas aeruginosa; beta-Lactamases
PubMed: 35786775
DOI: 10.1093/jac/dkac210 -
3 Biotech Mar 2022Production of biosurfactant by a novel indigenous isolate strain DU13 and its role in bioremediation of petroleum hydrocarbon is reported. The identity of the isolate...
Production of biosurfactant by a novel indigenous isolate strain DU13 and its role in bioremediation of petroleum hydrocarbon is reported. The identity of the isolate was confirmed by 16S rDNA gene sequencing analysis (Genbank accession: MK177190). The biosurfactant produced by the isolate could reduce the surface tension of petroleum supplemented medium by 46% just after 7 days of treatment. The emulsification index ( ) of the surfactant was found 37, 35, and 20%, respectively, against used motor oil, diesel, and kerosene. The FTIR spectrum of the crude biosurfactant showed the presence of υ stretch, υ υ stretch and υ bonding. The isolated strain could degrade 26% of TPH content of used motor oil in liquid culture. Whereas, ex situ pilot-scale field trial demonstrated very high bioremediation potential of the isolate in terms of germination rate of and seeds and plant growth just after 20 days of treatment.
PubMed: 35223354
DOI: 10.1007/s13205-022-03133-2 -
International Journal of Systematic and... Nov 2021Strain TUM18999 was isolated from the skin of a patient with burn wounds in Japan. The strain was successfully cultured at 20-42 °C (optimum, 30-35 °C) in 1.0-4.0%...
Strain TUM18999 was isolated from the skin of a patient with burn wounds in Japan. The strain was successfully cultured at 20-42 °C (optimum, 30-35 °C) in 1.0-4.0% NaCl (w/v) and at pH 5.5-9.5, optimum pH 5.5-8.5. The phylogenetic tree reconstructed using 16S rRNA, , and gene sequences indicated that strain TUM18999 is closely related to MCC10330. Although the partial 16S rRNA gene sequence (1412 bp) of TUM18999 exhibits high similarity to those of NBRC 14159 (99.08 %) and MCC10330 (98.51 %), multi-locus sequence analysis using 16S rRNA, , and genes reveals a clear distinction between TUM18999 and other species. In addition, an average nucleotide identity >90 % was not observed in the group. Moreover, TUM18999 and can be distinguished based on the minimum inhibitory concentration for carbapenem. Meanwhile, the cellular fatty acids are enriched with C 7/C 6 (34.35 %), C 7/C 6 (24.22 %), C (19.79 %) and C (8.25 %). Based on this evidence, strain TUM18999 can be defined as representing a novel species, with the proposed name sp. nov. The type strain is TUM18999 (GTC 22698=NCTC 14580).
Topics: Bacterial Typing Techniques; Base Composition; Burns; DNA, Bacterial; Fatty Acids; Genes, Bacterial; Humans; Japan; Phylogeny; Pseudomonas; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Skin
PubMed: 34762579
DOI: 10.1099/ijsem.0.005115 -
Journal of Water and Health May 2023Metallo-β-lactamases (MBLs) encoding carbapenem resistance in wastewater are a well-known serious threat to human health. Twelve Pseudomonas otitidis isolates obtained...
Metallo-β-lactamases (MBLs) encoding carbapenem resistance in wastewater are a well-known serious threat to human health. Twelve Pseudomonas otitidis isolates obtained from a municipal wastewater treatment plant (WWTP) in Hawaii were found to possess a subclass B3 MBL - POM (P. otitidis MBL), with a minimum inhibition concentration (MIC) range of 8-16 mg/L. The unrooted neighbor-joining phylogenetic tree showed that these bla genes isolated in wastewater samples (n = 12) were distinctly different from other reference genes isolated from clinical, freshwater, animal, and soil samples except for isolates MR7, MR8, and MR11. MR7, MR8, and MR11 were found to have 4, 3, and 3 amino acid substitutions when compared to the type strain MC10330 and were closely clustered to the clinical reference genes. The meropenem hydrolysis experiment showed that isolates with multiple amino acid substitutions completely hydrolyzed 64 mg/L of meropenem in 7 h. The emergence of the opportunistic pathogen P. otitidis chromosomally encoding bla in the treated municipal wastewater is an alarming call for the spread of this MBL in the environment. Further studies are required to understand the mechanism and regulation of this carbapenem-resistant β-lactamase in order to fill in the knowledge gap.
Topics: Animals; Humans; Carbapenems; Meropenem; Anti-Bacterial Agents; Wastewater; Phylogeny; beta-Lactamases; Microbial Sensitivity Tests; Pseudomonas aeruginosa
PubMed: 37254905
DOI: 10.2166/wh.2023.255 -
Pathogens (Basel, Switzerland) Dec 2022is a rare and unique species among the genus that has not been previously reported as a cause of male genitourinary tract infection. In this report, we describe a case...
is a rare and unique species among the genus that has not been previously reported as a cause of male genitourinary tract infection. In this report, we describe a case of a 20-year-old immunocompetent male who presented with recurrent epididymo-orchitis, which was initially misidentified as Vibrio vulnificus and treated successfully. The causative agent could not be identified appropriately using the available routine methods, but a final identification was established using 16S rRNA targeted sequencing followed by whole-genome sequencing.
PubMed: 36558809
DOI: 10.3390/pathogens11121475