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Food Research International (Ottawa,... Nov 2020Pixian broad bean paste (PBP) is a traditional Chinese condiment, famous for its distinctive flavor. Microbial communities play a vital role in producing the unique...
Pixian broad bean paste (PBP) is a traditional Chinese condiment, famous for its distinctive flavor. Microbial communities play a vital role in producing the unique flavor of PBP, and a significant accumulation of these volatile flavors occurs during the post-fermentation stage of its production. However, little is known about the relationship between the microbes and flavor compounds in PBP. In this study, high-throughput sequencing (HTS) analysis revealed that Leuconostoc (8.30%), Lactobacillus (7.05%), Weissella (5.80%) and Staphylococcus (4.03%) were the dominant bacterial genera, while the most prevalent yeast genera were Zygosaccharomyces (41.45%) and Pichia (5.83%). Gradual accumulations of free amino acids (glutamic acid and asparagine), organic acids (malic acid and tartaric acid), and unique volatiles (aldehydes, phenols and pyrazines) were evident throughout the post-fermentation process. Analysis of the Pearson's correlation coefficients between 66 key microbes and the key flavors was investigated. Nine core microbes were identified based on the linear discriminant analysis (LDA) scores ≥ 4 (or an average abundance >0.1%) and a high correlation with at least two flavor categories (P < 0.05, |ρ| > 0.8), namely Kosakonia, Kazachstania, Debaryomyces, Lactobacillus, Myroides, Stenotrophomonas, Ochrobactrum, Wohlfahrtiimonas, and Lactococcus genera. These results provide a clearer insight into microbial succession during PBP post-fermentation, thereby contributing to further quality improvement of PBP.
Topics: Fermentation; Flavoring Agents; Microbiota; Taste; Vicia faba
PubMed: 33233148
DOI: 10.1016/j.foodres.2020.109513 -
Japanese Journal of Infectious Diseases Nov 2020Myroides spp. are low-grade opportunistic pathogens. Outbreaks due to Myroides spp. have rarely been described in the literature to date. We report a...
Myroides spp. are low-grade opportunistic pathogens. Outbreaks due to Myroides spp. have rarely been described in the literature to date. We report a healthcare-associated outbreak of urinary tract infections (UTIs), caused by Myroides odoratimimus, in a Turkish hospital. As of March 2019 until May 2019, 6 strains of M. odoratimimus were isolated from the urine samples of patients, all of whom were hospitalized in intensive care units. After identification and antibiotic susceptibility testing using the VITEK 2 system, MALDI-TOF-MS and 16S rRNA-based sequencing methods were performed for confirmation and species-level identification. Pulsed-field gel electrophoresis (PFGE) was performed in order to investigate the clonal relatedness of the isolates. All the patients were immunocompromised and underwent urinary catheterization. None of the patients had urinary neoplasm, surgery, or calculi. VITEK 2 and MALDI-TOF-MS systems revealed that the isolates belonged to the Myroides genus; however, the aforementioned systems neglected to identify the isolates at the species level. The isolates were all successfully identified as M. odoratimimus through 16S rRNA-based sequencing. The isolates were resistant to every antibiotic tested. All isolates had an indistinguishable PFGE pattern, thus indicating cross-transmission between cases. Although M. odoratimimus is rarely isolated from human specimens, clinicians should be aware of its ability to cause UTIs and infectious outbreaks.
Topics: Aged; Aged, 80 and over; Anti-Bacterial Agents; Cross Infection; Disease Outbreaks; Drug Resistance, Multiple, Bacterial; Electrophoresis, Gel, Pulsed-Field; Female; Flavobacteriaceae; Flavobacteriaceae Infections; Hospitalization; Humans; Immunocompromised Host; Male; Microbial Sensitivity Tests; Middle Aged; RNA, Bacterial; RNA, Ribosomal, 16S; Turkey; Urinary Catheterization; Urinary Tract Infections
PubMed: 33208588
DOI: 10.7883/yoken.JJID.2019.536 -
Theriogenology Dec 2020Although the effects of sperm microbiota and sperm quality have been described previously, recent studies provide evidence that female genital modifications triggered by...
Although the effects of sperm microbiota and sperm quality have been described previously, recent studies provide evidence that female genital modifications triggered by seminal components could be of significant importance to identify some disturbances associated with fertility. So, sperm microbiota could play a key role in sperm quality, contributing to fertilisation. To understand how sperm microbiota diversity is influenced by the host genetics, the symbiotic bacteria in four inbred lines raised in the same animal facility and their effects on sperm quality and fertility were analysed. Forty healthy rabbits from four selected Spanish commercial lines were used in this research (three based on litter performance, designated A, V and LP, and one selected for daily body weight gain, called R). Significant variations in the seminal concentration, morphology and some motion parameters were found among inbred lines, but sperm motility and viability were similar among inbred lines. After mating, inbred lines selected for litter size had the same fertility rate, significantly higher than inbred line selected for body weight (82 ± 3.3%, 79 ± 3.5% and 89 ± 4.5% versus 61 ± 3.7%, for the A, V and LP vs R lines, respectively, p < 0.05). Bacteria belonging to Proteobacteria, Firmicutes, Fusobacteria and Bacteroidetes were identified in sperm microbiota. At genus level, the bacterial community composition in the sperm microbiota was influenced by host genetics. A total of 35, 16, 34, and 51 genera were accurately detected in the A, V, LP, and R lines, respectively. Moreover, Enhydrobacter, Ferruginibacter, Myroides Paracoccus, Rheinheimera, Tepidiphilus, Tetradesmus obliquus and Thauera genera were present only in the inbred lines selected for litter size. Moreover, the discriminant analysis revealed Lysinibacillus and Flavobacterium genera as potential biomarkers for fertility. Thus, these two genera may play a key role in fertility. Our results demonstrated the existence of a rabbit inbred line-specific variation in bacterial occurrence in sperm microbiota. Moreover, fertility differentials among inbred lines that were not predicted by routine semen analysis could be partly explained by the symbiotic state of the semen microbiota.
Topics: Animals; Female; Fertility; Male; Microbiota; Rabbits; Semen; Sperm Motility; Spermatozoa
PubMed: 33039925
DOI: 10.1016/j.theriogenology.2020.09.028 -
International Journal of Systematic and... Oct 2020A bacterial strain, BIT-d1, was isolated from the gut of plastic-eating larvae of the coleopteran insect . Its taxonomic position was analysed using a polyphasic...
A bacterial strain, BIT-d1, was isolated from the gut of plastic-eating larvae of the coleopteran insect . Its taxonomic position was analysed using a polyphasic approach. Cells were white-pigmented, Gram-stain-negative, non-motile, long rods without flagella. The 16S rRNA gene sequence (1401 bp) of strain BIT-d1 showed highest similarity (98.0%) to SM1 and 96.6~92.6 % similarity to the other species of the genus . The results of phylogenetic analyses, based on the 16S rRNA gene, concatenated sequences of six housekeeping genes (, , , , and ) and genome sequences, placed strain BIT-d1 in a separate lineage among the genus , family . The major isoprenoid quinone was menaquinone-6 (MK-6) and the major fatty acids were C iso, C iso 3-OH and summed feature 9 (comprising iso-C 9 and/or C 10-methyl), which were similar to other members in the genus DNA-DNA hybridization and average nucleotide identity calculations plus physiological and biochemical tests exhibited the genotypic and phenotypic differentiation of strain BIT-d1 from the other members of the genus . Therefore, strain BIT-d1 is considered to represent a novel species within the genus , for which the name sp. nov is proposed. The type strain is BIT-d1 (=CGMCC 1.17043=KCTC 72447).
Topics: Animals; Bacterial Typing Techniques; Base Composition; China; Coleoptera; DNA, Bacterial; Fatty Acids; Flavobacteriaceae; Gastrointestinal Microbiome; Gastrointestinal Tract; Genes, Bacterial; Larva; Nucleic Acid Hybridization; Phylogeny; Plastics; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Vitamin K 2
PubMed: 32894215
DOI: 10.1099/ijsem.0.004429 -
Water Research Oct 2020Antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) were investigated from effluent of two hospital and two municipal wastewater treatment plants...
Antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) were investigated from effluent of two hospital and two municipal wastewater treatment plants (WWTPs) before and after disinfection. The results of network analysis showed that 8 genera were identified to be the main potential hosts of ARGs, including Mycobacterium, Ferruginibacter, Thermomonas, Morganella, Enterococcus, Bacteroides, Myroides and Romboutsia. The removal of ARGs and their possible bacterialhosts were synchronous and consistent by chlorine or ultraviolet (UV) disinfection in WWTPs. The mechanisms of ARB and ARGs removal, and conjugation transfer of RP4 plasmids by UV, chlorine and synergistic UV/chlorine disinfection was revealed. Compared to UV alone, ARB inactivation was improved 1.4 log and photoreactivation was overcomeeffectively by UV/chlorine combination (8 mJ/cm, chlorine 2 mg/L). However, ARGs degradation was more difficult than ARB inactivation. Until UV dosage enhanced to 320 mJ/cm, ARGs achieved 0.58-1.60 log removal. Meanwhile, when 2 mg/L of chlorine was combined with UV combination, ARGs removal enhanced 1-1.5 log. The synergistic effect of adding low-dose chlorine (1-2 mg/L) during UV radiation effectively improved ARB and ARGs removal simultaneously. The same synergistic effect also occurred in the horizontal gene transfer (HGT). Non-lethal dose chlorine (0.5 mg/L) increased the conjugation transfer frequency,which confirmed that the mRNA expression levels of type IV secretion system (T4SS) proteins vir4D, vir5B and vir10B were significantly enhanced. The risk of RP4 plasmid conjugation transfer was significantly reduced with UV/chlorine (UV ≥ 4 mJ/cm, chlorine ≥ 1 mg/L). These findings may serve as valuable implications for assessing and controlling the risk of ARGs transfer and propagation in the environment.
Topics: Anti-Bacterial Agents; Bacteria; Chlorine; Disinfection; Drug Resistance, Bacterial; Drug Resistance, Microbial; Genes, Bacterial; Wastewater
PubMed: 32818733
DOI: 10.1016/j.watres.2020.116290 -
Infection and Drug Resistance 2020Catheter-related infection (CRI) is one of the most frequent causes of hospitalizations for immunocompromised patients. A major challenge is the increased prevalence of...
PURPOSE
Catheter-related infection (CRI) is one of the most frequent causes of hospitalizations for immunocompromised patients. A major challenge is the increased prevalence of . The purpose of the present study was to evaluate the clinical features and molecular characteristics of collected from a general hospital in Shanghai, China.
PATIENTS AND METHODS
From July 2015 to August 2016, a total of 22 isolates of were collected from inpatients respectively from the biliary and pancreatic surgery (6/22) and the urology department (16/22). Clonal relatedness among the isolates was assessed using pulsed-field gel electrophoresis (PFGE) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Moreover, the antimicrobial susceptibility tests were carried out using the Clinical and Laboratory Standards Institute (CLSI) broth microdilution method. The presence of antibiotic resistance genes was screened using the polymerase chain reaction (PCR) assay. Additionally, protein structure prediction was analyzed using PSIPRED and RaptorX.
RESULTS
PFGE differentiated these isolates into six possibly related clones from two different departments obtained during a distinct period, indicating clonal dissemination in the two departments. We compared the dendrograms of isolates obtained by MALDI-TOF MS with those obtained by PFGE and found that the coincidence rate between them was only 68.2%. All the isolates were highly resistant to most available antibiotics, including carbapenems. Furthermore, chromosome-encoded β-lactamases MUS-1 was confirmed by PCR in 6 of 22 isolates. Herein, we also reported a novel variant of in the remaining 16 isolates, which encodes MUS-3 protein at position 60 (Valine to Alanine), differing from the structure of MUS-1.
CONCLUSION
The opportunistic and extensively antibiotic-resistant has a small range of epidemics in these two different departments. Clinicians should be aware that may induce a severe nosocomial outbreak of catheter-related infections, particularly in immunocompromised patients.
PubMed: 32612373
DOI: 10.2147/IDR.S251626 -
Microbial Pathogenesis Oct 2020Gut bacterial microbiota is altered in patients with chronic kidney disease (CKD) and those on dialysis. However, it is not yet clear what bacterial composition changes...
BACKGROUND
Gut bacterial microbiota is altered in patients with chronic kidney disease (CKD) and those on dialysis. However, it is not yet clear what bacterial composition changes occur in patients with idiopathic nephrotic syndrome (INS). We present in this report the changes in gut bacterial microbiota in INS patients with membranous nephropathy.
METHODS
A total of 158 individuals were recruited for this study. Of these, 80 patients had stage 3-5 CKD without nephrotic syndrome (CKD group), 48 patients had INS and pathological diagnosis of membranous nephropathy (INS group), and 30 were age- and sex-matched healthy controls (HC group). The gut microbiome composition was analyzed using a 16S ribosomal RNA gene-based sequencing protocol.
RESULTS
The results indicate that the nephrotic syndrome patients had a significantly different alpha and beta diversity compared with the CKD group and HC group (P < 0.01). At the phylum level, the INS patients showed increased Fusobacteria and Proteobacteria but reduced Firmicutes when compared with the HC group. At the genus level, Megamonas, Megasphaera, Akkermansia, and the butyrate-producing bacteria Lachnospira, Roseburia, and Fusobacterium were more abundant in the HC group (LDA score > 3) than the CKD and INS group. Fecal organic acid analysis revealed significantly lower quantities of propionate acid and butyric acid in INS than the HC group (P < 0.05). Compared with the HC group, we found that Parabacteroides was increased in CKD and INS patients. In addition, Oscillospira and Ruminococcus were more abundant in CKD patients than in the other two groups (LDA score > 3). At the genus level, ten bacterial taxa were more prevalent in the HC group. Providencia and Myroides were more prevalent in INS patients.
CONCLUSION
Our findings highlight that, INS patients had a significantly different alpha and beta diversity and decreased gut microbiota-derived short-chain fatty acids, such as butyrate. However, large-scale prospective studies should be performed to identify the cause and effect factors of these changes in the microbiota in INS patients.
Topics: Adult; Dysbiosis; Feces; Gastrointestinal Microbiome; Glomerulonephritis, Membranous; Humans; Nephrotic Syndrome; Prospective Studies; RNA, Ribosomal, 16S; Renal Dialysis
PubMed: 32599137
DOI: 10.1016/j.micpath.2020.104359 -
Ecotoxicology (London, England) Sep 2020Effluents are commonly discharged into water bodies, and in order for the process to be as environmentally sound as possible, the potential effects on native water...
Effluents are commonly discharged into water bodies, and in order for the process to be as environmentally sound as possible, the potential effects on native water communities must be assessed alongside the quality parameters of the effluents themselves. In the present work, changes in the bacterial diversity of streamwater receiving a tannery effluent were monitored by high-throughput MiSeq sequencing. Physico-chemical and microbiological parameters and acute toxicity were also evaluated through different bioassays. After the discharge of treated effluents that had been either naturally attenuated or bioaugmented, bacterial diversity decreased immediately in the streamwater samples, as evidenced by the over-representation of taxa such as Brachymonas, Arcobacter, Marinobacterium, Myroides, Paludibacter and Acinetobacter, typically found in tannery effluents. However, there were no remarkable changes in diversity over time (after 1 day). In terms of the physico-chemical and microbiological parameters analyzed, chemical oxygen demand and total bacterial count increased in response to discharge of the treated effluents. No lethal effects were observed in Lactuca sativa L. seeds or Rhinella arenarum embryos exposed to the streamwater that had received the treated effluents. All of these results contribute to the growing knowledge about the environmental safety of effluent discharge procedures.
Topics: Animals; Argentina; Bufo arenarum; High-Throughput Nucleotide Sequencing; Industrial Waste; Lactuca; Microbiota; Rivers; Tanning; Toxicity Tests, Acute; Wastewater
PubMed: 32556791
DOI: 10.1007/s10646-020-02237-w -
Microorganisms Jun 2020The potential utilization of black soldier fly () as food or feed is interesting due to the nutritive value and the sustainability of the rearing process. In the present...
The potential utilization of black soldier fly () as food or feed is interesting due to the nutritive value and the sustainability of the rearing process. In the present study, larvae and prepupae of were reared at 20, 27, and 33 °C, to determine whether temperature affects the whole insect microbiota, described using microbiological risk assessment techniques and 16S rRNA gene survey. The larvae efficiently grew across the tested temperatures. Higher temperatures promoted faster larval development and greater final biomass but also higher mortality. Viable Enterobacteriaceae, , , , coagulase-positive staphylococci, , and were detected in prepupae. and counts got higher with the increasing temperature. Based on 16S rRNA gene analysis, the microbiota of larvae was dominated by (>60%) and other (mainly ) and evolved to a more complex composition in prepupae, with a bloom of , , and , while was still present as the main component. Prepupae largely shared the microbiota with the frass where it was reared, except for few lowly represented taxa. The rearing temperature was negatively associated with the amount of , and positively associated with a variety of other genera, such as , , , , , , , , and . With respect to the microbiological risk assessment, attention should be paid to abundant genera, such as , , , , and , which encompass species described as opportunistic pathogens, bearing drug resistances or causing severe morbidity.
PubMed: 32549385
DOI: 10.3390/microorganisms8060902 -
Japanese Journal of Infectious Diseases May 2020Myroides spp. are low-grade opportunistic pathogens. There were only a few outbreaks due to Myroides spp. described in the literature to date. We report a...
Myroides spp. are low-grade opportunistic pathogens. There were only a few outbreaks due to Myroides spp. described in the literature to date. We report a healthcare-associated outbreak of urinary tract infections caused by Myroides odoratimimus in a Turkish hospital. From March to May 2019, six strains of M. odoratimimus were isolated from the urine samples of patients hospitalized in the intensive care units (ICUs). After identification and antibiotic susceptibility testing with VITEK 2 system, MALDI-TOF-MS and 16S rRNA based sequencing methods were performed for confirmation and species level identification. Pulsed-field gel electrophoresis (PFGE) was used to investigate clonal relatedness of the isolates. All the patients were immunocompromised and underwent urinary catheterization. None of them had urinary neoplasm, surgery or calculi. VITEK 2 and MALDI-TOF-MS systems revealed that the isolates belong to the Myroides genus but lacked to identify the isolates at the species level. 16S rRNA based sequencing successfully identified all the isolates as M. odoratimimus. The isolates were resistant to all antibiotics tested. All isolates had indistinguishable PFGE pattern indicating cross-transmission between cases. Although M. odoratimimus is rarely isolated from human specimens, clinicians should be aware of its ability to cause UTIs and outbreaks.
PubMed: 32475882
DOI: 10.7883/yoken.JJJID.2019.536