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Clinical Case Reports Dec 2021is a Gram-negative, oxidase-negative motile rod which is rarely isolated from human caused a few opportunistic infections in immunocompromised patients so far. We...
is a Gram-negative, oxidase-negative motile rod which is rarely isolated from human caused a few opportunistic infections in immunocompromised patients so far. We report the first case of otitis media combined with externa caused by . in an immunocompetent patient. A 56-year-old male patient visited the outpatient clinic of the Otolaryngology Department due to otorrhea of the right ear started after diving in mountain valley in Korea 3 days ago. He was immunocompetent adult and clinical examination revealed swelling and debris accumulation in the right external auditory canal with an intact, erythematous tympanic membrane, and clear, odorless otorrhea. Microbiological culture of otorrhea revealed . by matrix-assisted laser desorption/ionization time-of-flight and PCR-based 16S rRNA gene sequencing. His otorrhea persisted, and a pinpoint perforation occurred in the inferior anterior portion of the tympanic membrane. 50% acetic acid irrigation and 500 mg of oral ciprofloxacin were prescribed, and his infection was cured after 4 weeks. This is the first case of otitis media combined with externa caused by in an immunocompetent patient. Given that species infections are rare, especially in immunocompetent patients, this case highlights the importance of history taking and communication between clinicians and laboratory physicians. Molecular identification methods assist in identifying rare pathogens.
PubMed: 34938553
DOI: 10.1002/ccr3.5177 -
PloS One 2018The Southern green stinkbug (N. viridula) feeds on developing soybean seeds in spite of their strong defenses against herbivory, making this pest one of the most harmful...
The Southern green stinkbug (N. viridula) feeds on developing soybean seeds in spite of their strong defenses against herbivory, making this pest one of the most harmful to soybean crops. To test the hypothesis that midgut bacterial community allows stinkbugs to tolerate chemical defenses of soybean developing seeds, we identified and characterized midgut microbiota of stinkbugs collected from soybean crops, different secondary plant hosts or insects at diapause on Eucalyptus trees. Our study demonstrated that while more than 54% of N. viridula adults collected in the field had no detectable bacteria in the V1-V3 midgut ventricles, the guts of the rest of stinkbugs were colonized by non-transient microbiota (NTM) and transient microbiota not present in stinkbugs at diapause. While transient microbiota Bacillus sp., Micrococcus sp., Streptomyces sp., Staphylococcus sp. and others had low abundance, NTM microbiota was represented by Yokenella sp., Pantoea sp. and Enterococcus sp. isolates. We found some isolates that showed in vitro β-glucosidase and raffinase activities plus the ability to degrade isoflavonoids and deactivate soybean protease inhibitors. Our results suggest that the stinkbugs´ NTM microbiota may impact on nutrition, detoxification and deactivation of chemical defenses, and Enterococcus sp., Yokenella sp. and Pantoea sp. strains might help stinkbugs to feed on soybean developing seeds in spite of its chemical defenses.
Topics: Animals; Cysteine Proteinase Inhibitors; DNA, Bacterial; Enterobacteriaceae; Enterococcus; Gastrointestinal Microbiome; Heteroptera; Host-Pathogen Interactions; Pantoea; Phylogeny; Phytochemicals; Plant Diseases; Glycine max; Symbiosis
PubMed: 30001328
DOI: 10.1371/journal.pone.0200161 -
Microorganisms Apr 2023Recent bacteriological investigations of freshwater mussel mortality events in the southeastern United States have identified a variety of bacteria and differences in...
A Bacteriological Comparison of the Hemolymph from Healthy and Moribund Unionid Mussel Populations in the Upper Midwestern U.S.A. Prompts the Development of Diagnostic Assays to Detect .
Recent bacteriological investigations of freshwater mussel mortality events in the southeastern United States have identified a variety of bacteria and differences in bacterial communities between sick and healthy mussels. In particular, and spp. have been shown to be associated with moribund mussels, although it remains unclear whether these bacteria are causes or consequences of disease. To further understand the role of bacteria in mussel epizootics, we investigated mortality events that occurred in the upper Midwest in the Embarrass River (Wisconsin) and the Huron River (Michigan). For comparison, we also studied mussels from an unaffected population in the St. Croix River (Wisconsin). Diverse bacterial genera were identified from these sites, including from moribund mussels in the Embarrass River (Wisconsin). This bacterium has also been consistently isolated during ongoing mortality events in the Clinch River (Virginia). Subsequently, we developed and validated molecular assays for the detection of to use in future investigations of mussel mortality events and to identify environmental reservoirs of this bacterium.
PubMed: 37110491
DOI: 10.3390/microorganisms11041068 -
Foods (Basel, Switzerland) Mar 2023A comprehensive study of bacterial and biotoxin contaminants of ready-to-eat (RTE) foods in Nigeria is yet to be reported. Hence, this study applied 16S rRNA gene...
A comprehensive study of bacterial and biotoxin contaminants of ready-to-eat (RTE) foods in Nigeria is yet to be reported. Hence, this study applied 16S rRNA gene sequencing and a dilute-and-shoot LC-MS/MS method to profile bacteria and biotoxins, respectively, in 199 RTE food samples comprising (n = 30) bread (n = 30), shawarma (n = 35), (n = 35), biscuits (n = 34), and (n = 35). A total of 631 bacterial isolates, clustered into seven operational taxonomic units, namely , , , and , , and , that are reported for the first time were recovered from the foods. One hundred and eleven metabolites comprising mycotoxins and other fungal metabolites, phytoestrogenic phenols, phytotoxins, and bacterial metabolites were detected in the foods. Aflatoxins, fumonisins, and ochratoxins contaminated only the artisanal foods (, and ), while deoxynivalenol and zearalenone were found in industrially-processed foods (biscuit, bread, and shawarma), and citrinin was present in all foods except . Mean aflatoxin (39.0 µg/kg) in artisanal foods exceeded the 10 µg/kg regulatory limit adopted in Nigeria by threefold. Routine surveillance, especially at the informal markets; food hygiene and safety education to food processors and handlers; and sourcing of high-quality raw materials are proposed to enhance RTE food quality and safeguard consumer health.
PubMed: 36981151
DOI: 10.3390/foods12061224 -
Communications Biology Jan 2024The nasal cavity harbors diverse microbiota that contributes to human health and respiratory diseases. However, whether and to what extent the host genome shapes the...
The nasal cavity harbors diverse microbiota that contributes to human health and respiratory diseases. However, whether and to what extent the host genome shapes the nasal microbiome remains largely unknown. Here, by dissecting the human genome and nasal metagenome data from 1401 healthy individuals, we demonstrated that the top three host genetic principal components strongly correlated with the nasal microbiota diversity and composition. The genetic association analyses identified 63 genome-wide significant loci affecting the nasal microbial taxa and functions, of which 2 loci reached study-wide significance (p < 1.7 × 10): rs73268759 within CAMK2A associated with genus Actinomyces and family Actinomycetaceae; and rs35211877 near POM121L12 with Gemella asaccharolytica. In addition to respiratory-related diseases, the associated loci are mainly implicated in cardiometabolic or neuropsychiatric diseases. Functional analysis showed the associated genes were most significantly expressed in the nasal airway epithelium tissue and enriched in the calcium signaling and hippo signaling pathway. Further observational correlation and Mendelian randomization analyses consistently suggested the causal effects of Serratia grimesii and Yokenella regensburgei on cardiometabolic biomarkers (cystine, glutamic acid, and creatine). This study suggested that the host genome plays an important role in shaping the nasal microbiome.
Topics: Humans; Genome-Wide Association Study; Nose; Microbiota; Genetic Variation; Cardiovascular Diseases
PubMed: 38291185
DOI: 10.1038/s42003-024-05822-5 -
Applied and Environmental Microbiology Apr 2014A novel whole-cell biocatalyst with high allylic alcohol-oxidizing activities was screened and identified as Yokenella sp. WZY002, which chemoselectively reduced the C=O...
Characterization of an allylic/benzyl alcohol dehydrogenase from Yokenella sp. strain WZY002, an organism potentially useful for the synthesis of α,β-unsaturated alcohols from allylic aldehydes and ketones.
A novel whole-cell biocatalyst with high allylic alcohol-oxidizing activities was screened and identified as Yokenella sp. WZY002, which chemoselectively reduced the C=O bond of allylic aldehydes/ketones to the corresponding α,β-unsaturated alcohols at 30°C and pH 8.0. The strain also had the capacity of stereoselectively reducing aromatic ketones to (S)-enantioselective alcohols. The enzyme responsible for the predominant allylic/benzyl alcohol dehydrogenase activity was purified to homogeneity and designated YsADH (alcohol dehydrogenase from Yokenella sp.), which had a calculated subunit molecular mass of 36,411 Da. The gene encoding YsADH was subsequently expressed in Escherichia coli, and the purified recombinant YsADH protein was characterized. The enzyme strictly required NADP(H) as a coenzyme and was putatively zinc dependent. The optimal pH and temperature for crotonaldehyde reduction were pH 6.5 and 65°C, whereas those for crotyl alcohol oxidation were pH 8.0 and 55°C. The enzyme showed moderate thermostability, with a half-life of 6.2 h at 55°C. It was robust in the presence of organic solvents and retained 87.5% of the initial activity after 24 h of incubation with 20% (vol/vol) dimethyl sulfoxide. The enzyme preferentially catalyzed allylic/benzyl aldehydes as the substrate in the reduction of aldehydes/ketones and yielded the highest activity of 427 U mg(-1) for benzaldehyde reduction, while the alcohol oxidation reaction demonstrated the maximum activity of 79.9 U mg(-1) using crotyl alcohol as the substrate. Moreover, kinetic parameters of the enzyme showed lower Km values and higher catalytic efficiency for crotonaldehyde/benzaldehyde and NADPH than for crotyl alcohol/benzyl alcohol and NADP(+), suggesting the nature of being an aldehyde reductase.
Topics: Alcohol Oxidoreductases; Aldehydes; Benzyl Alcohol; Cloning, Molecular; Coenzymes; DNA, Bacterial; Enterobacteriaceae; Enzyme Stability; Escherichia coli; Gene Expression; Hydrogen-Ion Concentration; Ketones; Molecular Sequence Data; Molecular Weight; NADP; Propanols; Sequence Analysis, DNA; Substrate Specificity; Temperature; Zinc
PubMed: 24509923
DOI: 10.1128/AEM.03980-13 -
Microorganisms Jan 2022The exploration of certain microbial resources such as beneficial endophytic microorganisms is considered a promising strategy for the discovery of new antimicrobial...
The exploration of certain microbial resources such as beneficial endophytic microorganisms is considered a promising strategy for the discovery of new antimicrobial compounds for the pharmaceutical industries and agriculture. Thirty-one endophytic bacterial strains affiliated with , , , , , and were previously isolated from vetiver ( (L.) Roberty) roots. These endophytes showed antifungal activity against and could be a source of antimicrobial metabolites. In this study, in particular, using high-throughput screening, we analyzed their antagonistic activities and those of their cell-free culture supernatants against three species of plant pathogens, a bacterial strain of , and a yeast strain of , as well as their capacity to produce lipopeptides. The results showed that the culture supernatants of four strains close to species exhibited antimicrobial activities against species and . Using mass spectrometry analyses, we identified two groups of lipopeptides (surfactins and plipastatins) in their culture supernatants. Whole-genome sequencing confirmed that these bacteria possess NRPS gene clusters for surfactin and plipastatin. In vitro tests confirmed the inhibitory effect of plipastatin alone or in combination with surfactin against the three species.
PubMed: 35208667
DOI: 10.3390/microorganisms10020209 -
Access Microbiology 2023, belonging to the order , is a rare and emerging human pathogen reported to cause both superficial and invasive infections. The 13 case reports in the literature...
, belonging to the order , is a rare and emerging human pathogen reported to cause both superficial and invasive infections. The 13 case reports in the literature worldwide highlight blood, bone and wound infections. To our knowledge this is the first case description of causing a urinary tract infection in a 69-year-old immunocompetent patient which was isolated in two separate specimens and identified using matrix-assisted laser desorption ionization time-of-flight MS. It was found to be susceptible to most antimicrobials but resistant to penicillin, amoxicillin-clavulanate, cefoxitin and colistin. Inducible chromosomal resistance was demonstrated on disc approximation testing, and YOC-1 class C beta-lactamase, beta lactamase superfamily and MBL fold metallo-hydrolase genes were found on whole genome sequencing.
PubMed: 37970085
DOI: 10.1099/acmi.0.000571.v4 -
infection in an immunocompetent individual after trauma following a fall from a personal conveyance.Journal of the Association of Medical... Mar 2023infections have been documented in several immunocompromised individuals with numerous associated risk factors including soft tissue infections, organ transplants, and...
BACKGROUND
infections have been documented in several immunocompromised individuals with numerous associated risk factors including soft tissue infections, organ transplants, and metabolic disorders. Our report presents a rare case of Y. infection in an immunocompetent individual.
METHODS
In September 2020, a 38-year-old man who was otherwise healthy fell from a personal conveyance causing a puncture of his elbow. Two months later, he was admitted to the hospital with a chronic draining wound on his left arm with no fever (36.7°C) and stable vital signs. The patient underwent white blood cell (WBC) imaging, and single-photon emission computed tomography (SPECT/CT) to rule out osteomyelitis. Incision and drainage were performed, and the collected fluid was sent to a microbiology lab for culture diagnosis. Subsequently, matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) analysis and antimicrobial susceptibility testing were performed.
RESULTS
A WBC image and SPECT/CT test showed an increase in WBC uptake and activity in the subcutaneous tissue of the left arm. The culture diagnosis identified the isolate as and the patient received 2 weeks of sulfamethoxazole 800 mg and trimethoprim 160 mg orally twice daily based on the results of the antimicrobial susceptibility testing. He demonstrated clinical improvements shown through wound healing and reduced pain.
CONCLUSION
This report supports the potential of to act as an opportunistic pathogen even in hosts with no prior underlying diseases or conditions.
PubMed: 37008588
DOI: 10.3138/jammi-2022-0018 -
Journal of Gastrointestinal Surgery :... Aug 2020Recently, the link between obesity and gut microbiota has become a focus for research. This study shed some light on the modification of postoperative gut microbial...
BACKGROUND
Recently, the link between obesity and gut microbiota has become a focus for research. This study shed some light on the modification of postoperative gut microbial composition after bariatric surgery.
METHODS
A prospective longitudinal study on healthy lean subjects and patients who underwent bariatric surgery (Roux-en-Y gastric bypass and laparoscopic sleeve gastrectomy) was carried out. Anthropometric and metabolic data, smoking, food preferences data, and stool samples were collected from lean subjects and from obese patients before and 3 and 6 months after surgery (T0, T3, and T6, respectively).
RESULTS
We collected stool samples from 25 obese patients before surgery and 3 and 6 months thereafter and from 25 normal weight patients. After Roux-en-Y gastric bypass, Yokenella regensburgei (p < 0.05), Fusobacterium varium (p < 0.05), Veillonella dispar/atypica (p < 0.05), and Streptococcus australis/gordonii (p < 0.05) were transiently identified in the gut at T3. Roux-en-Y gastric bypass patients had a permanent increase in Akkermansia muciniphila (p < 0.05), which is associated with healthy metabolism, both at T3 and T6. There were no significant changes in gut microbiota in laparoscopic sleeve gastrectomy patients.
CONCLUSIONS
In our study, Roux-en-Y gastric bypass induced major microbial differences and greater weight loss compared with laparoscopic sleeve gastrectomy. Analyzing the microbiota composition, a proliferation of potential pathogens and the onset of beneficial bacteria was observed. The effects of these bacteria on human health are still far from clear. Understanding the mechanisms of action of these bacteria could be the keystone in developing new therapeutic strategies for obesity.
Topics: Bariatric Surgery; Enterobacteriaceae; Fusobacterium; Gastrectomy; Gastric Bypass; Gastrointestinal Microbiome; Humans; Laparoscopy; Longitudinal Studies; Obesity, Morbid; Prospective Studies; Streptococcus; Veillonella
PubMed: 31388884
DOI: 10.1007/s11605-019-04321-x