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Journal of Biotechnology Feb 2024l-Lactate oxidase has important applications in biosensing and finds increased use in biocatalysis. The enzyme has been characterized well, yet its immobilization has...
l-Lactate oxidase has important applications in biosensing and finds increased use in biocatalysis. The enzyme has been characterized well, yet its immobilization has not been explored in depth. Here, we studied immobilization of Aerococcus viridansl-lactate oxidase on porous carriers of variable matrix material (polymethacrylate, polyurethane, agarose) and surface functional group (amine, Ni-loaded nitrilotriacetic acid (NiNTA), epoxide). Carrier activity (A) and immobilized enzyme effectiveness (ɳ) were evaluated in dependence of protein loading. Results show that efficient immobilization (A: up to 1450 U/g carrier; ɳ: up to 65%) requires a hydrophilic carrier (agarose) equipped with amine groups. The value of ɳ declines sharply as A increases, probably due to transition into diffusional regime. Untagged l-lactate oxidase binds to NiNTA carrier similarly as N-terminally His-tagged enzyme. Lixiviation studies reveal quasi-irreversible enzyme adsorption on NiNTA carrier while partial release of activity (≤ 25%) is shown from amine carrier. The desorbed enzyme exhibits the same specific activity as the original l-lactate oxidase. Collectively, our study identifies basic requirements of l-lactate oxidase immobilization on solid carrier and highlights the role of ionic interactions in enzyme-surface adsorption.
Topics: Aerococcus; Sepharose; Mixed Function Oxygenases; Enzymes, Immobilized; Amines
PubMed: 38280467
DOI: 10.1016/j.jbiotec.2024.01.011 -
Clinical Chemistry and Laboratory... Jun 2024The EFLM Task and Finish Group Urinalysis has updated the ECLM European Urinalysis Guidelines (2000) on urinalysis and urine bacterial culture, to improve accuracy of...
BACKGROUND
The EFLM Task and Finish Group Urinalysis has updated the ECLM European Urinalysis Guidelines (2000) on urinalysis and urine bacterial culture, to improve accuracy of these examinations in European clinical laboratories, and to support diagnostic industry to develop new technologies.
RECOMMENDATIONS
Graded recommendations were built in the following areas.
MEDICAL NEEDS AND TEST REQUISITION
Strategies of urine testing are described to patients with complicated or uncomplicated urinary tract infection (UTI), and high or low-risk to kidney disease.
SPECIMEN COLLECTION
Patient preparation, and urine collection are supported with two quality indicators: contamination rate (cultures), and density of urine (chemistry, particles).
CHEMISTRY
Measurements of both urine albumin and α1-microglobulin are recommended for sensitive detection of kidney disease in high-risk patients. Performance specifications are given for urine protein measurements and quality control of multiproperty strip tests.
PARTICLES
Procedures for microscopy are reviewed for diagnostic urine particles, including urine bacteria. Technologies in automated particle counting and visual microscopy are updated with advice how to verify new instruments with the reference microscopy.
BACTERIOLOGY
Chromogenic agar is recommended as primary medium in urine cultures. Limits of significant growth are reviewed, with an optimised workflow for routine specimens, using leukocyturia to reduce less important antimicrobial susceptibility testing. Automation in bacteriology is encouraged to shorten turn-around times. Matrix assisted laser desorption ionization time-of-flight mass spectrometry is applicable for rapid identification of uropathogens. and are taken into the list of uropathogens. A reference examination procedure was developed for urine bacterial cultures.
PubMed: 38534005
DOI: 10.1515/cclm-2024-0070 -
Genome Announcements Apr 2016Strains belonging to the genus Aerococcus are causative agents of human and animal infections, including urogenital infections, bacteremia/septicemia, and infective...
Complete Genome Sequences of Aerococcus christensenii CCUG 28831T, Aerococcus sanguinicola CCUG 43001T, Aerococcus urinae CCUG 36881T, Aerococcus urinaeequi CCUG 28094T, Aerococcus urinaehominis CCUG 42038 BT, and Aerococcus viridans CCUG 4311T.
Strains belonging to the genus Aerococcus are causative agents of human and animal infections, including urogenital infections, bacteremia/septicemia, and infective endocarditis. This study reports the first fully closed and complete genome sequences of six type strains belonging to the genus Aerococcus using a combination of Illumina HiSeq and PacBio sequencing technologies.
PubMed: 27103727
DOI: 10.1128/genomeA.00302-16 -
Environmental Research Apr 2019The airborne fungal and bacterial species present in pig farm dust have not been well characterised even though these bioaerosols are known to cause inflammation and...
The airborne fungal and bacterial species present in pig farm dust have not been well characterised even though these bioaerosols are known to cause inflammation and other airway maladies. In this study, the microbial species and composition in airborne dust within and between pig farms were investigated. Passively sedimenting dust from six pig farms were collected using electrostatic dust collectors. The bacterial and fungal species were identified using matrix-assisted laser desorption-ionisation time-of-flight mass spectrometry (MALDI-TOF MS) and next generation sequencing (NGS). Dust samples taken within the same stable section revealed high resemblance and stability. Constrained statistical analysis of the microbial community compositions indicated that the types of stable did not appear to have a great effect on the bacterial and fungal β-diversity. In contrast to this, the farm from which samples were taken appeared to have the greatest effect on the bacterial β-diversity, but this trend was not observed for the fungal β-diversity. The most common bacteria and fungi according to NGS data were anaerobes typically associated with the pig intestinal tract and yeasts respectively. Bacterial sedimentation varied at a rate between 10 and 10 CFU/m/day, with the most common species after aerobic incubation being Aerococcus viridans and Staphylococcus equorum, while Clostridium perfringens and Staphylococcus simulans were the most common species after anaerobic incubation. A total of 28 different species of bacteria and fungi were classifiable as pathogens. In conclusion, the biodiversity in pig farm dust shows a high diversity of bacterial species. However, samples from the same stable section resembled each other, but also different sections within the same farm also resembled each other, thus indicating a high degree of community stability in the dust source. In regards to fungal identification, the biodiversity was observed to be similar between samples from different stable sections and farms, indicating a higher degree of similarities in the mycobiomes found across pig farms studied.
Topics: Air Microbiology; Animals; Bacteria; Biodiversity; Dust; Environmental Monitoring; Farms; Fungi; Swine
PubMed: 30771719
DOI: 10.1016/j.envres.2019.01.008 -
The American Journal of Case Reports May 2019BACKGROUND Aerococcus viridans are Gram-positive, catalase and oxidase-negative, microaerophilic, and non-motile bacteria species that are rarely associated with human... (Review)
Review
BACKGROUND Aerococcus viridans are Gram-positive, catalase and oxidase-negative, microaerophilic, and non-motile bacteria species that are rarely associated with human infections such as arthritis, bacteremia, endocarditis, and meningitis. The bacteria are also fastidious (i.e., have complex nutritional requirements) and often confused with Streptococci species or treated as a contaminant. CASE REPORT We report a case of Aerococcus septicemia in an 85-year-old female patient, who transferred from a nursing home to an acute care hospital in Washington DC, USA. She had a 2-day history of worsening mental status, fever of 38.9°C (102°F), and tachycardia. Urinalysis revealed numerous white blood cells and bacteria. Laboratory tests revealed a white blood cell count of 14 000 cells/mL (85% neutrophils, 8% lymphocytes, 5% bands, and 2% monocytes), hemoglobin of 12.6 g/dL, and serum creatinine of 0.8 mg/dL. Blood and urine cultures obtained during admission grew penicillin-resistant A. viridans, identified via matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF) on day 3 of admission. The patient received empiric vancomycin with piperacillin-tazobactam, and we deescalated to vancomycin monotherapy to complete a 14-day treatment course. CONCLUSIONS This case report highlights the role of MALDI-TOF for identifying fastidious organisms, and we were able to form a better clinical correlation between patient symptoms and causative organisms. We believe that antimicrobial therapy (in accordance with susceptibility results) should be initiated in symptomatic patients who have A. viridans isolated in significant amounts in urine or from a sterile site.
Topics: Aerococcus; Aged, 80 and over; Female; Gram-Positive Bacterial Infections; Humans; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
PubMed: 31089069
DOI: 10.12659/AJCR.914866 -
BMC Microbiology Mar 2021Composition and maintenance of the microbiome is vital to gut homeostasis. However, there is limited knowledge regarding the impact of high doses of radiation, which can...
BACKGROUND
Composition and maintenance of the microbiome is vital to gut homeostasis. However, there is limited knowledge regarding the impact of high doses of radiation, which can occur as a result of cancer radiation therapy, nuclear accidents or intentional release of a nuclear or radioactive weapon, on the composition of the gut microbiome. Therefore, we sought to analyze alterations to the gut microbiome of nonhuman primates (NHPs) exposed to high doses of radiation. Fecal samples were collected from 19 NHPs (Chinese rhesus macaques, Macaca mulatta) 1 day prior and 1 and 4 days after exposure to 7.4 Gy cobalt-60 gamma-radiation (LD). The 16S V4 rRNA sequences were extracted from each sample, followed by bioinformatics analysis using the QIIME platform.
RESULTS
Alpha Diversity (Shannon Diversity Index), revealed no major difference between pre- and post-irradiation, whereas Beta diversity analysis showed significant differences in the microbiome after irradiation (day + 4) compared to baseline (pre-irradiation). The Firmicutes/Bacteriodetes ratio, a factor known to be associated with disruption of metabolic homeostasis, decreased from 1.2 to less than 1 post-radiation exposure. Actinobacillus, Bacteroides, Prevotella (Paraprevotellaceae family) and Veillonella genera were significantly increased by more than 2-fold and Acinetobacter and Aerococcus genus were decreased by more than 10-fold post-irradiation. Fifty-two percent (10/19) of animals exposed to radiation demonstrated diarrhea at day 4 post-irradiation. Comparison of microbiome composition of feces from animals with and without diarrhea at day 4 post-irradiation revealed an increase in Lactobacillus reuteri associated with diarrhea and a decrease of Lentisphaerae and Verrucomicrobioa phyla and Bacteroides in animals exhibiting diarrhea. Animals with diarrhea at day 4 post-irradiation, had significantly lower levels of Lentisphaere and Verrucomicrobia phyla and Bacteroides genus at baseline before irradiation, suggesting a potential association between the prevalence of microbiomes and differential susceptibility to radiation-induced diarrhea.
CONCLUSIONS
Our findings demonstrate that substantial alterations in the microbiome composition of NHPs occur following radiation injury and provide insight into early changes with high-dose, whole-body radiation exposure. Future studies will help identify microbiome biomarkers of radiation exposure and develop effective therapeutic intervention to mitigate the radiation injury.
Topics: Animals; Bacteria; Feces; Gamma Rays; Gastrointestinal Microbiome; Macaca mulatta; RNA, Ribosomal, 16S; Radiation Injuries
PubMed: 33781201
DOI: 10.1186/s12866-021-02146-w -
Case Reports in Urology 2015A 49-year-old male presented to the emergency with hematuria and pain in the shaft of the penis for one day. The patient was found to be in a state of shock. The shaft...
A 49-year-old male presented to the emergency with hematuria and pain in the shaft of the penis for one day. The patient was found to be in a state of shock. The shaft of the penis and the scrotum were swollen and tender. No skin necrosis was observed and no crepitus was palpable. Serum white count (WBC) was 29.5 × 10(3)/μL. A CT scan showed gas in the corpus spongiosum. Antibiotics were started with IV metronidazole, vancomycin, and piperacillin/tazobactam. Metronidazole was then replaced by clindamycin. Exploration was performed but no necrotic tissue was identified. Cystourethroscopy revealed dusky looking urethra. A suprapubic tube and a urethral catheter were placed in the bladder. WBC trended down to 13.9 × 10(3)/μL on the fourth postoperative day. Urine culture grew Aerococcus urinae and blood cultures grew Alpha Hemolytic Streptococcus. On the sixth day, the patient was feeling worse and WBC increased. MRI revealed absent blood flow to the corpus spongiosum. Urethroscopy revealed necrosis of the urethra. Urethrectomy was performed via perineal approach. The patient immediately improved. The patient was discharged on the sixth postoperative day to continue ampicillin/sulbactam IV every 6 hours for a total of 4 weeks from the day of urethrectomy.
PubMed: 26171271
DOI: 10.1155/2015/136147 -
Experimental Gerontology Dec 2022We induced the AD-like rat models injected by AlCl and D-galactose, to explore the effects of an oral treatment of A. muciniphila on AD-like rats with periodontitis and...
AIMS
We induced the AD-like rat models injected by AlCl and D-galactose, to explore the effects of an oral treatment of A. muciniphila on AD-like rats with periodontitis and its possible mechanism.
MAIN METHODS
We used Morris water maze test and micro-CT to assess the cognitive impairment and bone loss; Aβ1-42 deposition was tested by IHC; Serum LPS level and TG, HDL-C and AST/ALT levels were detected by LAL Test and biochemical tests; The gut microbiota was analyzed by 16S rRNA gene sequence.
KEY FINDINGS
We found that A. muciniphila could alleviate AD-like rats' cognitive impairment and mitigate ligature-induced periodontitis. Furthermore, A. muciniphila reduced Aβ1-42 deposition in the cortex and regions of the rats' brain, and altered TG, HDL-C and AST/ALT levels but had little ability to change circulating LPS level and cross the blood-brain barrier. Notably, A. muciniphila treatment could improve the abundance of some short chain fatty acid (SCFA)-producing or neurotransmitter-producing gut microbiome such as Blautia, Staphylococcus and Lactococcus, while the abundance of pathogenic Aerococcus and Streptococcus, which were associated inflammation, were decreased.
SIGNIFICANCE
Our findings suggested that A. muciniphila has a remissive effect on AD-like pathologies, potentially by regulating gut-brain axis through altering composition and function of gut microbial community or moderating peripheral circulation metabolism.
Topics: Animals; Rats; Alzheimer Disease; Aluminum Chloride; Galactose; RNA, Ribosomal, 16S; Lipopolysaccharides; Verrucomicrobia; Periodontitis; Probiotics
PubMed: 36152776
DOI: 10.1016/j.exger.2022.111959 -
Archives of Gynecology and Obstetrics Jan 2020This study aimed to investigate the gut microbiome composition in pregnant women with digestive diseases to analyze the relationships between the microflora changes and...
PURPOSE
This study aimed to investigate the gut microbiome composition in pregnant women with digestive diseases to analyze the relationships between the microflora changes and digestive diseases during pregnancy.
METHODS
Fecal samples obtained from 71 pregnant women [six acute fatty liver (AF group), 21 constipation (C group), 24 excessive vomiting (V group) and 20 normal pregnancy (CP group)] and 26 non-pregnant (NP group) women were subjected to 16 s rRNA sequencing. Differential analysis of intestinal flora at the genera level was performed.
RESULTS
The relative abundance of Coprobacillus, Acinetobacter, Enterococcus, Weissella and Lysinibacillus was increased in the digestive diseases (AF, C and V) groups compared with CP group, whereas that of five common genera, including Terrisporobacter, Dysgonomonas, Adlercreutzia, Fusicatenibacter and Blautia, was decreased in digestive diseases groups. Additionally, in digestive diseases (AF, C and V) groups, the abundance of 13 common genera, such as Carnobacterium, Coprobacillus and Psychrobacter, was higher than NP group, whereas that of 27 common genera, such as Blautia and Terrisporobacter, was lower than NP group. About 69 genera were differentially abundant between AF and C groups; two genera (Aerococcus and Senegalimassilia) were identified between AF and V groups; moreover, total 63 genera were obtained between C and V groups.
CONCLUSION
Our data revealed that the abundance of Acinetobacter, Enterococci, Paenibacillus, Blautia and Collinsella might be associated with the digestive diseases during pregnancy. These findings further supported the idea that targeting the gut microbiota could be a new prevention or therapeutic approach for improving digestive diseases during pregnancy.
Topics: Adult; Female; Gastrointestinal Diseases; Gastrointestinal Microbiome; Humans; Pregnancy; Young Adult
PubMed: 31776707
DOI: 10.1007/s00404-019-05336-0 -
Reproductive Biology and Endocrinology... Jan 2024Increasing number of studies have demonstrated certain patterns of microbial changes in gynecological diseases; however, the interaction between them remains unclear. To... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Increasing number of studies have demonstrated certain patterns of microbial changes in gynecological diseases; however, the interaction between them remains unclear. To evaluate the consistency or specificity across multiple studies on different gynecological diseases and microbial alterations at different sites of the body (gut and genital tract), we conducted a systematic review and meta-analysis.
METHODS
We searched PubMed, Embase, Web of Science, and Cochrane Library up to December 5, 2022(PROSPERO: CRD42023400205). Eligible studies focused on gynecological diseases in adult women, applied next-generation sequencing on microbiome, and reported outcomes including alpha or beta diversity or relative abundance. The random-effects model on standardized mean difference (SMD) was conducted using the inverse-variance method for alpha diversity indices.
RESULTS
Of 3327 unique articles, 87 eligible studies were included. Significant decreases were found in gut microbiome of patients versus controls (observed species SMD=-0.35; 95%CI, -0.62 to -0.09; Shannon index SMD=-0.23; 95%CI, -0.40 to -0.06), whereas significant increases were observed in vaginal microbiome (Chao1 SMD = 1.15; 95%CI, 0.74 to 1.56; Shannon index SMD = 0.51; 95%CI, 0.16 to 0.86). Most studies of different diagnostic categories showed no significant differences in beta diversity. Disease specificity was observed, but almost all the changes were only replicated in three studies, except for the increased Aerococcus in bacterial vaginosis (BV). Patients with major gynecological diseases shared the enrichment of Prevotella and depletion of Lactobacillus, and an overlap in microbes was implied between BV, cervical intraepithelial neoplasia, and cervical cancer.
CONCLUSIONS
These findings demonstrated an association between alterations in gut and genital microbiota and gynecological diseases. The most observed results were shared alterations across diseases rather than disease-specific alterations. Therefore, further investigation is required to identify specific biomarkers for diagnosis and treatment in the future.
Topics: Adult; Humans; Female; Microbiota; Vaginosis, Bacterial; Gastrointestinal Microbiome; Vagina; Uterine Cervical Neoplasms
PubMed: 38238814
DOI: 10.1186/s12958-024-01184-z