-
Frontiers in Microbiology 2023In recent years, researchers have been exploring the plastic-degrading abilities of bacteria residing in the guts of Styrofoam-eating larvae. However, none of the...
INTRODUCTION
In recent years, researchers have been exploring the plastic-degrading abilities of bacteria residing in the guts of Styrofoam-eating larvae. However, none of the reported strains have displayed highly efficient plastic degradation capabilities, and it's noteworthy that none of the existing studies have focused on strictly anaerobic microbes.
METHODS
In this study, we exclusively fed Styrofoam to larvae and examined how this dietary change influence the gut's bacterial community composition, as observed through fecal bacteria using bacterial 16S rRNA gene amplicon sequencing and the small-scale culturomics method with 20 types of anaerobic media under four different conditions.
RESULTS
The results revealed a significant shift in the dominant phylogroup from (37.8%) to (54.7%) when comparing the feces of larvae fed with bran and Styrofoam, as analyzing through the bacterial 16S rRNA gene amplicon sequencing. For small-scale culturomics method, a total of 226 strains of anaerobic bacteria were isolated and purified using the rolling-tube/strictly anaerobic technique. Among them, 226 strains were classified into 3 phyla, 7 classes, 9 orders, 17 families, 29 genera, 42 known species and 34 potential novel species.
DISCUSSION
Interestingly, 24 genera in total, identified through the culturomics method, were not found in the results obtained from amplicon sequencing. Here, we present a collection of culturable anaerobic bacteria from the feces of larvae, which might be a promising avenue for investigating the biodegradability of plastics by combining specific strains, either randomly or intentionally, while considering the abundance ratio of the microbial community composition.
PubMed: 38116533
DOI: 10.3389/fmicb.2023.1309806 -
Infection and Drug Resistance 2022To explore the clinical value of detecting pathogens in pus samples by metagenomic next-generation sequencing (mNGS).
PURPOSE
To explore the clinical value of detecting pathogens in pus samples by metagenomic next-generation sequencing (mNGS).
METHODS
The 25 pus samples from infected patients were collected in this research. The positive rate and consistency of pathogenic bacteria detected by mNGS and conventional methods were compared. The pathogen types detected by the two methods were analyzed. Furthermore, the modifications of antibiotic treatment therapy were also evaluated based on mNGS results.
RESULTS
The sensitivity of mNGS method in detecting pathogenic bacteria in pus samples was better than that of conventional method (96% vs 40%; P < 0.01). Only 10 samples were detected pathogens by conventional methods, but 24 samples were detected by mNGS method. In specific, the results of conventional methods showed 10 samples had 11 kinds of pathogenic bacteria, of which 9 samples were single pathogen and 1 sample had two kinds of pathogenic bacteria. The results of mNGS method showed 24 samples were detected with 54 kinds of pathogenic bacteria, of which 15 samples were detected with single pathogen, and 9 samples were detected with two or more kinds of pathogenic bacteria. The two methods had 9(36%) consistent results, 14 (56%) completely different results, and 2 (8%) partially consistent results, and the kappa value was 0.19. Notably, mNGS could detect viruses, anaerobic bacteria, and other uncommon pathogens simultaneously.
CONCLUSION
The application of mNGS in the detection of pus specimens from different parts not only have high accuracy rate and also reduce the turnaround time of diagnosis. In addition, the performance of mNGS detection of anaerobic bacteria and caustic bacteria is better than conventional methods. The mNGS diagnosis in pus sample may play an important role in clinical diagnosis and treatment strategy decisions.
PubMed: 36386420
DOI: 10.2147/IDR.S385925 -
Revista Espanola de Quimioterapia :... Apr 2023The objective of this study was to perform a systematic review of the characteristics, causative microorganisms and outcome of brain abscesses caused by anaerobic...
The objective of this study was to perform a systematic review of the characteristics, causative microorganisms and outcome of brain abscesses caused by anaerobic bacteria over the past 25 years. We reviewed studies on brain abscesses which included infection due to anaerobic microorganisms published between 1998 and 2022. We excluded reports with polymicrobial infections (more than 2 anaerobic bacteria isolated) and those that do not provide enough information to make comparisons, the reports with only one case of brain abscess due to anaerobes, as well as those focused on an only anaerobic bacterium. Also, we have excluded the cases in pediatric population. We searched the scientific literature through the Cochrane Library, EMBASE and PubMed/MEDLINE databases for studies of this condition. We finally included 28 studies with 6,167 patients, of which 715 (11.5%) were cases caused by anaerobic bacteria. There was a male predominance (70%) and mean age of 40.3 years. Most infections were monomicrobial (59.4%). The most common anaerobic microorganisms isolated were Bacteroides spp (43.4%) and Gram-positive anaerobic cocci (35.1%). Cases of brain abscesses caused by anaerobic bacteria were most frequent in Asia and Europe. The source of infection most frequent was otogenic in 84.6% followed by a neurosurgery procedure infection in 23% of patients. The main symptom observed was headache in 95.6% of patients followed by fever (69.5%). Surgical treatment was performed in 48 % of patients and the percentage of patients in whom antibiotic treatment was applied range 88.8% to 100%. The main limitation of this review is the non-inclusion of studies published before of 1998 in which MALDI-TOF MS system had not been introduced in the majority of laboratories for routine identification. The patient rate with isolation of anaerobic bacteria in brain abscesses is low, but these data could be underestimated mainly due to the fastidious nature of these microorganisms and the difficulties in the identification of some anaerobes.
Topics: Humans; Male; Child; Adult; Female; Anaerobiosis; Base Composition; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Brain Abscess; Bacteria, Anaerobic; Gram-Positive Cocci
PubMed: 36733997
DOI: 10.37201/req/114.2022 -
Microorganisms Dec 2022This study aimed to investigate the presence of both aerobic and anaerobic bacteria in a water sample collected from a nuclear power plant and establish if the...
This study aimed to investigate the presence of both aerobic and anaerobic bacteria in a water sample collected from a nuclear power plant and establish if the indigenous bacteria or the products of their metabolic activities could initiate the corrosion of two different types of carbon steel (i.e., A570, 1045). The aerobic (heterotrophic, iron-oxidizing) and anaerobic (sulfate-reducing) bacteria were detected in low numbers in the water sample. Three bacterial strains were isolated by the enrichment procedure from this sample. Based on phenotypic and genotypic characteristics, the isolated bacteria were identified as IBB (MT893712), IBB (MT893713), and IBB (MT893714). The bacteria existing in the water sample were able to initiate the corrosion of carbon steel A570 and 1045. The sulfate-reducing bacteria were detected in higher numbers than the heterotrophic bacteria and iron-oxidizing bacteria at the end of the biocorrosion experiments. The carbon steel coupons revealed macroscopic and microscopic changes in the surface characteristics, and these changes could be due to biofilm formation on their surfaces and the accumulation of the corrosion products. The corrosion rate varied from one type of carbon steel to another, depending on the incubation conditions and the chemical composition of the coupons.
PubMed: 36557704
DOI: 10.3390/microorganisms10122451 -
Scientific Reports Oct 2020Recently, it was suggested that the nitrite (NO) produced from NO by oral bacteria might contribute to oral and general health. Therefore, we aimed to clarify the...
Recently, it was suggested that the nitrite (NO) produced from NO by oral bacteria might contribute to oral and general health. Therefore, we aimed to clarify the detailed information about the bacterial NO-production in the oral biofilm. Dental plaque and tongue-coating samples were collected, then the NO-producing activity was measured. Furthermore, the composition of the NO-producing bacterial population were identified using the Griess reagent-containing agar overlay method and molecular biological method. NO-producing activity per mg wet weight varied among individuals but was higher in dental plaque. Additionally, anaerobic bacteria exhibited higher numbers of NO-producing bacteria, except in the adults' dental plaque. The proportion of NO-producing bacteria also varied among individuals, but a positive correlation was found between NO-producing activity and the number of NO-producing bacteria, especially in dental plaque. Overall, the major NO-producing bacteria were identified as Actinomyces, Schaalia, Veillonella and Neisseria. Furthermore, Rothia was specifically detected in the tongue coatings of children. These results suggest that dental plaque has higher NO-producing activity and that this activity depends not on the presence of specific bacteria or the bacterial compositions, but on the number of NO-producing bacteria, although interindividual differences were detected.
Topics: Actinomyces; Actinomycetaceae; Adolescent; Adult; Bacteria, Anaerobic; Biofilms; Child; Child, Preschool; Dental Plaque; Female; Humans; Male; Microbiota; Micrococcaceae; Mouth; Neisseria; Nitrites; Veillonella; Young Adult
PubMed: 33024169
DOI: 10.1038/s41598-020-73479-1 -
Microbiology Insights 2022Intracranial abscesses have been a diagnostic and therapeutic challenge since time immemorial for both the microbiologists and the neurosurgeons. There is paucity of...
BACKGROUND
Intracranial abscesses have been a diagnostic and therapeutic challenge since time immemorial for both the microbiologists and the neurosurgeons. There is paucity of detailed studies documenting the infecting organism causing brain abscesses in South India.
AIMS
The study aimed at identifying and assessing the prevalence of aerobic, anaerobic bacteria and fungi associated with brain abscesses at a tertiary care hospital in South India.
METHODS AND MATERIAL
Eight years data was collected from the records of culture reports from 2007 to 2010 and 2013 to 2018. The corresponding clinical case records were retrieved for the assessment of risk factors. Risk factors of brain abscess development were assessed based on clinical cases records.
RESULTS
Data from 140 brain abscess cases obtained over a period of 8 years were analyzed. Out of the 140 samples, 66 (47.14%) were culture positive in which 33 (50%) had single aerobic/facultative anaerobic bacteria, 20 (30.3%) had mixture of more than one aerobic/facultative anaerobic bacteria, 12 (18.18%) had single obligate anaerobic bacteria and 1(1.5%) sample had isolated. Among the total 92 isolates, (21/92, 23%) and (20/92, 22%) predominated. was the most common obligate anaerobe isolated. There were no fungal isolates. As there were various isolates isolated, hence there is heterogeneity of isolates detected Neuroanatomically, parietal lobe (45/140, 32%) was the most common location. Otogenic infection was the major risk factor for parietal and temporal lobe abscess ( value < .05).
CONCLUSIONS
It has become essential for the microbiologists to be aware of unusual isolates from brain abscess and its complex nature. Obscurity and difficulty in their microbiological diagnosis calls for more such detailed studies.
PubMed: 35784588
DOI: 10.1177/11786361221106111 -
Journal of Personalized Medicine Jun 2021To selectively and continuously produce anti-cancer molecules specifically in malignant tumors, we have established an in situ delivery and production system (DPS) with... (Review)
Review
To selectively and continuously produce anti-cancer molecules specifically in malignant tumors, we have established an in situ delivery and production system (DPS) with as a micro-factory of various anti-cancer agents. By focusing on the characteristic hypoxia in cancer tissue for a tumor-specific target, we employed a gene-engineered obligate anaerobic and non-pathogenic bacterium, , as a tool for systemic drug administration. This review presents and discusses the anti-tumor effects and safety of the DPS production of numerous anti-cancer molecules and addresses the problems to be improved by directing attention mainly to the hallmark vasculature and so-called enhanced permeability and retention effect of tumors.
PubMed: 34204302
DOI: 10.3390/jpm11060566 -
Anaerobe Jun 2022A lack of updated data on the burden and profile of anaerobic bloodstream infections (ABIs) exists. We assessed the incidence of ABIs and trends in antimicrobial... (Review)
Review
INTRODUCTION
A lack of updated data on the burden and profile of anaerobic bloodstream infections (ABIs) exists. We assessed the incidence of ABIs and trends in antimicrobial resistance in anaerobes isolated from blood in Italy.
MATERIAL AND METHODS
We conducted a retrospective study on 17 Italian hospitals (2016-2020). Anaerobes isolated from blood culture and their in vitro susceptibility profiles (EUCAST-interpreted) were registered and analyzed.
RESULTS
A total of 1960 ABIs were identified. The mean age of ABIs patients was 68.6 ± 18.5 years, 57.6% were males. The overall incidence rate of ABIs was 1.01 per 10.000 patient-days. Forty-seven% of ABIs occurred in medical wards, 17% in ICUs, 14% in surgical wards, 7% in hemato-oncology, 14% in outpatients. The three most common anti-anaerobic tested drugs were metronidazole (92%), clindamycin (89%) and amoxicillin/clavulanate (83%). The three most common isolated anaerobes were Bacteroides fragilis (n = 529), Cutibacterium acnes (n = 262) and Clostridium perfringens (n = 134). The lowest resistance rate (1.5%) was to carbapenems, whereas the highest rate (51%) was to penicillin. Clindamycin resistance was >20% for Bacteroides spp., Prevotella spp. and Clostridium spp. Metronidazole resistance was 9.2% after excluding C. acnes and Actinomyces spp. Bacteroides spp. showed an increased prevalence of clindamycin resistance through the study period: 19% in 2016, 33% in 2020 (p ≤ 0.001).
CONCLUSIONS
Our data provide a comprehensive overview of the epidemiology of ABIs in Italy, filling a gap that has existed since 1995. Caution is needed when clindamycin is used as empirical anti-anaerobic drug.
Topics: Aged; Aged, 80 and over; Anaerobiosis; Anti-Bacterial Agents; Bacteria, Anaerobic; Bacterial Infections; Clindamycin; Drug Resistance, Bacterial; Female; Humans; Male; Metronidazole; Microbial Sensitivity Tests; Middle Aged; Retrospective Studies; Sepsis
PubMed: 35568274
DOI: 10.1016/j.anaerobe.2022.102583 -
Molecules (Basel, Switzerland) Nov 2022Green propolis may represent a promising therapeutic alternative against dental anaerobic pathogens because of its antimicrobial action. This study aimed to evaluate the...
Green propolis may represent a promising therapeutic alternative against dental anaerobic pathogens because of its antimicrobial action. This study aimed to evaluate the antimicrobial and antibiofilm actions of Brazilian green propolis aqueous extract (BGP-AqExt) against dental anaerobic bacteria. The minimum inhibitory concentration (MIC) and minimum microbicide concentration (MMC) of the extract were determined against the standard strains (ATCC) of , , and . BGP-AqExt was chemically characterized by high-performance liquid chromatography with diode-array detection (HPLC-DAD) analysis. Antibiofilm action was measured by MTT and crystal violet tests. The data were statistically analyzed by ANOVA and Tukey (5%) tests. The extract had antimicrobial action against all tested anaerobic bacteria, with an MIC value of 55 mg/mL for all bacteria, an MMC of 27.5 mg/mL for and and 55 mg/mL for . Chemically, BGP-AqExt is composed of quercetin, gallic acid, caffeic and p-coumaric acid, drupani, kaempferol and Artepillin C. Significant reductions in biomass and metabolic action of biofilms were found after BGP-AqExt application. Therefore, BGP-AqExt has an antimicrobial and antibiofilm effect against dental anaerobic bacteria.
Topics: Propolis; Bacteria, Anaerobic; Anti-Infective Agents; Microbial Sensitivity Tests; Porphyromonas gingivalis; Anti-Bacterial Agents
PubMed: 36500223
DOI: 10.3390/molecules27238128 -
Correlation between antibiotic resistance and clinical outcome of anaerobic infections; mini-review.Anaerobe Dec 2021In anaerobic infections, the relationship between clinical failure and antibiotic resistance is difficult to demonstrate, especially in mixed anaerobic-aerobic... (Review)
Review
In anaerobic infections, the relationship between clinical failure and antibiotic resistance is difficult to demonstrate, especially in mixed anaerobic-aerobic infections. Single isolates of anaerobes in cases of bacteraemia revealed that treatment failures were due to inappropriate therapy. We review here cases, where the empiric treatment was unsuccessful due to resistance of anaerobic bacteria to the administered agents and where the change of the antibiotic allowed the patients to be cured. Many therapeutic failures could be linked to the lack of timely detection of resistance, including heteroresistance of the anaerobes. Disk diffusion or Etest methodology may be suitable, at least for rapidly growing anaerobes, to detect both resistance and heteroresistance to antibiotics widely used for empirical therapy.
Topics: Anti-Bacterial Agents; Bacteremia; Bacteria, Anaerobic; Bacterial Infections; Clinical Decision-Making; Disease Management; Drug Resistance, Bacterial; Humans; Microbial Sensitivity Tests; Prognosis; Treatment Outcome
PubMed: 34597797
DOI: 10.1016/j.anaerobe.2021.102463