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Frontiers in Microbiology 2021Bovine colostrum silage (BCS) is a technique used by milk producers for the conservation of bovine colostrum. However, it is necessary to ensure the safety and quality...
Bovine colostrum silage (BCS) is a technique used by milk producers for the conservation of bovine colostrum. However, it is necessary to ensure the safety and quality of BCS, as this food will be supplied to the animals. This study aimed to compare the physicochemical and microbiological compositions of colostrum silage at different fermentation times with milk and bovine colostrum (BC) quality parameters. BC samples were obtained from Jersey animals from one dairy farm. The BC samples ( = 21) were placed in 500-mL plastic bottles, stored vertically and anaerobically fermented for periods of 61-437 days. The following parameters of the physicochemical composition of the BCS were evaluated: acidity, protein, total solids and ash, using the methodologies of Adolfo Lutz Institute (2008). The microbiological analysis was developed according to the methodology proposed by Saalfeld et al. (2013), with adaptations. The acidity, total solids and protein over fermentation time (group 1: 61 to 154, group 2: 200 to 273, and group 3: 280 to 437 days) were not significantly different ( > 0.05). The ash content was significantly different ( < 0.05) in groups 1 and 3 and showed a decrease (moderate negative correlation of -0.63) with increasing fermentation time. Positive correlations were observed between total solids and the protein and ash contents. The genus of microorganisms with the highest occurrence was spp. (95.2% of BCS) and those of lesser occurrence included spp., spp., spp. and spp. (4.8% of BCS). BCS has a physicochemical composition similar to BC and showed changes during the fermentation period; however, the presence of pathogenic microorganisms in BCSs reinforces the need to further explore the quality parameters for BCS to ensure the safety of animals who receive this food.
PubMed: 34589069
DOI: 10.3389/fmicb.2021.708189 -
PloS One 2021As part of a screening programme for antibiotic-producing bacteria, a novel Actinomadura species was discovered from a soil sample collected in Santorini, Greece....
As part of a screening programme for antibiotic-producing bacteria, a novel Actinomadura species was discovered from a soil sample collected in Santorini, Greece. Preliminary 16S rRNA gene sequence comparisons highlighted Actinomadura macra as the most similar characterised species. However, whole-genome sequencing revealed an average nucleotide identity (ANI) value of 89% with A. macra, the highest among related species. Further phenotypic and chemotaxonomic analyses confirmed that the isolate represents a previously uncharacterised species in the genus Actinomadura, for which the name Actinomadura graeca sp. nov. is proposed (type strain 32-07T). The G+C content of A. graeca 32-07 is 72.36%. The cell wall contains DL-diaminopimelic acid, intracellular sugars are glucose, ribose and galactose, the predominant menaquinone is MK-9(H6), the major cellular lipid is phosphatidylinositol and fatty acids consist mainly of hexadecanoic acid. No mycolic acid was detected. Furthermore, A. graeca 32-07 has been confirmed as a novel producer of the non-ribosomal peptide antibiotic zelkovamycin and we report herein a provisional description of the unique biosynthetic gene cluster.
Topics: Actinomadura; Antimicrobial Cationic Peptides; Base Composition; Macrocyclic Compounds
PubMed: 34847153
DOI: 10.1371/journal.pone.0260413 -
Ecotoxicology and Environmental Safety Sep 2021Aerobic composting is commonly used to dispose livestock manure and is an efficient way to reduce antibiotic resistance genes (ARGs). Here, the effects of different...
Aerobic composting is commonly used to dispose livestock manure and is an efficient way to reduce antibiotic resistance genes (ARGs). Here, the effects of different quality substrates on the fate of ARGs were assessed during manure composting. Results showed that the total relative abundances of ARGs and intI1 in additive treatments were lower than that in control, and high quality treatment with low C/N ratio and lignin significantly decreased the relative abundance of tetW, ermB, ermC, sul1 and sul2 at the end of composting. Additionally, higher quality treatment reduced the relative abundances of some pathogens such as Actinomadura and Pusillimonas, and some thermotolerant degrading-related bacteria comprising Pseudogracilibacillus and Sinibacillus on day 42, probably owing to the change of composting properties in piles. Structural equation models (SEMs) further verified that the physiochemical properties of composting were the dominant contributor to the variations in ARGs and they could also indirectly impact ARGs by influencing bacterial community and the abundance of intI1. Overall, these findings indicated that additives with high quality reduced the reservoir of antibiotic resistance genes of livestock manure compost.
Topics: Animals; Bacteria; Carbon; Chickens; Composting; Drug Resistance, Microbial; Genes, Bacterial; Lignin; Manure; Microbiota; Nitrogen
PubMed: 34139628
DOI: 10.1016/j.ecoenv.2021.112413 -
Microbiological Research Oct 2022Gut microbiota is involved in maintaining homeostasis, and intestinal dysbiosis may lead to opportunistic infections and diseases. Pathogens can disrupt the gut...
Gut microbiota is involved in maintaining homeostasis, and intestinal dysbiosis may lead to opportunistic infections and diseases. Pathogens can disrupt the gut homeostasis and establish colonization, but how they modulate the microbiome and metabolome along the gut-lung axis warrants further investigation. In the present study, we used a classical low virulence Klebsiella pneumoniae (cKp) strain to address this question. We assessed the gut microbiome and lung metabolome in cKp-infected mice by 16S rRNA sequencing and untargeted liquid chromatography-mass spectrometry, respectively. Our data revealed that cKp infection reduced gut microbiota diversity and altered microbiome composition. Specifically, cKp infection increased the abundance of MWH-CFBk5 and Actinomadura and reduced the abundance of Lachnospiraceae_NK4A136_group, Clostridium sensu_stricto 1, Bifidobacterium, and Intestinimonas at the genus level. Notably, caffeine and caffeine metabolism were significantly affected in the lung by cKp infection. Moreover, Spearman correlation analysis revealed remarkable correlations of specific lung metabolites and bacteria species at the genus level. These findings suggest that cKp infection is linked to gut dysbiosis and alterations in the lung metabolome. This study is of significance for developing innovative gut microbiota-directed therapy for respiratory diseases.
Topics: Animals; Caffeine; Dysbiosis; Gastrointestinal Microbiome; Klebsiella pneumoniae; Lung; Metabolome; Mice; RNA, Ribosomal, 16S
PubMed: 35905579
DOI: 10.1016/j.micres.2022.127139 -
Journal of Virology Jan 2020To counteract the serious health threat posed by known and novel viral pathogens, drugs that target a variety of viruses through a common mechanism have attracted recent...
To counteract the serious health threat posed by known and novel viral pathogens, drugs that target a variety of viruses through a common mechanism have attracted recent attention due to their potential in treating (re)emerging infections, for which direct-acting antivirals are not available. We found that labyrinthopeptins A1 and A2, the prototype congeners of carbacyclic lanthipeptides, inhibit the proliferation of diverse enveloped viruses, including dengue virus, Zika virus, West Nile virus, hepatitis C virus, chikungunya virus, Kaposi's sarcoma-associated herpesvirus, cytomegalovirus, and herpes simplex virus, in the low micromolar to nanomolar range. Mechanistic studies on viral particles revealed that labyrinthopeptins induce a virolytic effect through binding to the viral membrane lipid phosphatidylethanolamine (PE). These effects are enhanced by a combined equimolar application of both labyrinthopeptins, and a clear synergism was observed across a concentration range corresponding to 10% to 90% inhibitory concentrations of the compounds. Time-resolved experiments with large unilamellar vesicles (LUVs) reveal that membrane lipid raft compositions (phosphatidylcholine [PC]/PE/cholesterol/sphingomyelin at 17:10:33:40) are particularly sensitive to labyrinthopeptins in comparison to PC/PE (90:10) LUVs, even though the overall PE amount remains constant. Labyrinthopeptins exhibited low cytotoxicity and had favorable pharmacokinetic properties in mice (half-life [] = 10.0 h), which designates them promising antiviral compounds acting by an unusual viral lipid targeting mechanism. For many viral infections, current treatment options are insufficient. Because the development of each antiviral drug is time-consuming and expensive, the prospect of finding broad-spectrum antivirals that can fight multiple, diverse viruses-well-known viruses as well as (re)emerging species-has gained attention, especially for the treatment of viral coinfections. While most known broad-spectrum agents address processes in the host cell, we found that targeting lipids of the free virus outside the host cell with the natural products labyrinthopeptin A1 and A2 is a viable strategy to inhibit the proliferation of a broad range of viruses from different families, including chikungunya virus, dengue virus, Zika virus, Kaposi's sarcoma-associated herpesvirus, and cytomegalovirus. Labyrinthopeptins bind to viral phosphatidylethanolamine and induce virolysis without exerting cytotoxicity on host cells. This represents a novel and unusual mechanism to tackle medically relevant viral infections.
Topics: Aedes; Animals; Bacteriocins; Cell Line; Membrane Microdomains; Phosphatidylethanolamines; Virus Diseases; Viruses
PubMed: 31666384
DOI: 10.1128/JVI.01471-19 -
PLoS Neglected Tropical Diseases Feb 2020Mycetoma is a neglected tropical disease characterized by nodules, scars, abscesses, and fistulae that drain serous or purulent material containing the etiological...
BACKGROUND
Mycetoma is a neglected tropical disease characterized by nodules, scars, abscesses, and fistulae that drain serous or purulent material containing the etiological agent. Mycetoma may be caused by true fungi (eumycetoma) or filamentous aerobic bacteria (actinomycetoma). Mycetoma is more frequent in the so-called mycetoma belt (latitude 15° south and 30° north around the Tropic of Cancer), especially in Sudan, Nigeria, Somalia, India, Mexico, and Venezuela. The introduction of new antibiotics with fewer side effects, broader susceptibility profiles, and different administration routes has made information on actinomycetoma treatment and outcomes necessary. The objective of this report was to provide an update on clinical, therapeutic, and outcome data for patients with actinomycetoma attending a reference center in northeast Mexico.
METHODOLOGY/PRINCIPAL FINDINGS
This was a retrospective, cross-sectional, descriptive study of 31 patients (male to female ratio 3.4:1) diagnosed with actinomycetoma by direct grain examination, histopathology, culture, or serology from January 2009 to September 2018. Most lesions were caused by Nocardia brasiliensis (83.9%) followed by Actinomadura madurae (12.9%) and Actinomadura pelletieri (3.2%). About 50% of patients had bone involvement, and the right leg was the most commonly affected region in 38.7% of cases. Farmers/agriculture workers were most commonly affected, representing 41.9% of patients. The most commonly used treatment regimen was the Welsh regimen (35.5% of cases), a combination of trimethoprim/sulfamethoxazole (TMP/SMX) plus amikacin, which had a 90% cure rate, followed by TMP/SMX plus amoxicillin/clavulanic acid in 19.4% of cases with a cure rate of 100%. In our setting, 28 (90.3%) patients were completely cured and three (9.7%) were lost to follow-up. Four patients required multiple antibiotic regimens due to recurrences and adverse effects.
CONCLUSIONS/SIGNIFICANCE
In our sample, actinomycetoma was predominantly caused by N. brasiliensis. Most cases responded well to therapy with a combination of TMP/SMX with amikacin or TMP/SMX and amoxicillin/clavulanic acid. Four patients required multiple antibiotics and intrahospital care.
Topics: Adolescent; Adult; Aged; Anti-Bacterial Agents; Female; Humans; Longitudinal Studies; Male; Mexico; Middle Aged; Mycetoma; Retrospective Studies; Young Adult
PubMed: 32097417
DOI: 10.1371/journal.pntd.0008123 -
Infection and Drug Resistance 2023was first isolated in 2012 in Gelibolu, Canakkale, Turkey, and has not been reported to be isolated from humans until now. We have isolated it from the bronchoalveolar...
BACKGROUND
was first isolated in 2012 in Gelibolu, Canakkale, Turkey, and has not been reported to be isolated from humans until now. We have isolated it from the bronchoalveolar lavage fluid (BLF) of a patient with pneumonia and found its drug resistance. It is the first time that has been isolated from humans since its discovery and naming. This case may provide new ideas and methods for the clinical diagnosis and treatment of pulmonary actinomycosis.
CASE DESCRIPTION
The patient was a 75-year-old male who was hospitalized in a township hospital and failed to improve after penicillin treatment. After admission to our hospital, the patient was treated with piperacillin/tazobactam according to clinical guidelines for 14 days. was isolated from the patient's BLF and was identified by 16S rRNA sequencing. This report shows the biological characteristics and in vitro drug susceptibility testing, as well as the genomics analysis based on next-generation sequencing (NGS). The results demonstrated that was easy to be mistakenly identified as dental caries by using the Merieux ANC identification card. Based on the MIC test, was susceptible to tetracyclines, quinolones and sulfonamides, but resistant to carbapenems, penicillins and cephalosporins. The K-B test results showed was highly sensitive to piperacillin/tazobactam. Genomic analysis based on NGS showed that the belongs to EF-Tu mutants conferring resistance to inhibitor , and .
CONCLUSION
is generally sensitive to Penicillin but is not. In vitro drug susceptibility test is needed to support individualized drug use to avoid delay in the disease.
PubMed: 37228659
DOI: 10.2147/IDR.S409701 -
International Journal of Molecular... Dec 2023Madurastatins are a group of pentapeptides containing an oxazoline moiety, and, in a few cases, an imidazolidinone ring as an additional structural feature. In our...
Madurastatins are a group of pentapeptides containing an oxazoline moiety, and, in a few cases, an imidazolidinone ring as an additional structural feature. In our search for new potential antiparasitic metabolites from natural sources, we studied the acetone extracts from a culture of sp. CA-135719. The LC/HRMS analysis of this extract identified the presence of the known madurastatins C1 (), D1 (), and D2 () together with additional members of the family that were identified as the new madurastatins H2 () and 33--D1 () after isolation and spectroscopic analysis. The planar structures of the new compounds were established by HRMS, ESI-qTOF-MS/MS, and 1D and 2D NMR data, and their absolute configuration was proposed using Marfey's and bioinformatic analyses of the biosynthetic gene cluster (BGC). A revision of the absolute configuration of madurastatins D1 and D2 is proposed. Additionally, madurastatins containing imidazolidinone rings are proved to be artifacts originating during acetone extraction of the bacterial cultures.
Topics: Solvents; Acetone; Biological Products; Tandem Mass Spectrometry; Antiparasitic Agents
PubMed: 38203471
DOI: 10.3390/ijms25010301 -
MSphere Mar 2021, one of the largest bacterial phyla, are ubiquitous in many of Earth's ecosystems and often act as defensive symbionts with animal hosts. Members of the phylum have...
, one of the largest bacterial phyla, are ubiquitous in many of Earth's ecosystems and often act as defensive symbionts with animal hosts. Members of the phylum have repeatedly been isolated from basidiomycete-cultivating fungus-farming termites that maintain a monoculture fungus crop on macerated dead plant substrate. The proclivity for antimicrobial and enzyme production of make them likely contributors to plant decomposition and defense in the symbiosis. To test this, we analyzed the prophylactic (biosynthetic gene cluster [BGC]) and metabolic (carbohydrate-active enzyme [CAZy]) potential in 16 (10 existing and six new genomes) termite-associated and compared these to the soil-dwelling close relatives. Using antiSMASH, we identified 435 BGCs, of which 329 (65 unique) were similar to known compound gene clusters, while 106 were putatively novel, suggesting ample prospects for novel compound discovery. BGCs were identified among all major compound categories, including 26 encoding the production of known antimicrobial compounds, which ranged in activity (antibacterial being most prevalent) and modes of action that might suggest broad defensive potential. Peptide pattern recognition analysis revealed 823 (43 unique) CAZymes coding for enzymes that target key plant and fungal cell wall components (predominantly chitin, cellulose, and hemicellulose), confirming a substantial degradative potential of these bacteria. Comparison of termite-associated and soil-dwelling bacteria indicated no significant difference in either BGC or CAZy potential, suggesting that the farming termite hosts may have coopted these soil-dwelling bacteria due to their metabolic potential but that they have not been subject to genome change associated with symbiosis. have repeatedly been isolated in fungus-farming termites, and our genome analyses provide insights into the potential roles they may serve in defense and for plant biomass breakdown. These insights, combined with their relatively higher abundances in fungus combs than in termite gut, suggest that they are more likely to play roles in fungus combs than in termite guts. Up to 25% of the BGCs we identify have no similarity to known clusters, indicating a large potential for novel chemistry to be discovered. Similarities in metabolic potential of soil-dwelling and termite-associated bacteria suggest that they have environmental origins, but their consistent presence with the termite system suggests their importance for the symbiosis.
Topics: Actinobacteria; Animals; Fungi; Genome, Bacterial; Genomics; Isoptera; Multigene Family; Phylogeny; Symbiosis
PubMed: 33658277
DOI: 10.1128/mSphere.01233-20 -
Antiviral Research May 2020Acute lower respiratory tract infections (ALRI) caused by respiratory syncytial virus (RSV) are associated with a severe disease burden among infants and elderly...
Acute lower respiratory tract infections (ALRI) caused by respiratory syncytial virus (RSV) are associated with a severe disease burden among infants and elderly patients. Treatment options are limited. While numerous drug candidates with different viral targets are under development, the utility of RSV entry inhibitors is challenged by a low resistance barrier and by single mutations causing cross-resistance against a wide spectrum of fusion inhibitor chemotypes. We developed a cell-based screening assay for discovery of compounds inhibiting infection with primary RSV isolates. Using this system, we identified labyrinthopeptin A1 and A2 (Laby A1/A2), lantibiotics isolated from Actinomadura namibiensis, as effective RSV cell entry inhibitors with ICs of 0.39 μM and 4.97 μM, respectively, and with favourable therapeutic index (>200 and > 20, respectively). Both molecules were active against multiple RSV strains including primary isolates and their antiviral activity against RSV was confirmed in primary human airway cells ex vivo and a murine model in vivo. Laby A1/A2 were antiviral in prophylactic and therapeutic treatment regimens and displayed synergistic activity when applied in combination with each other. Mechanistic studies showed that Laby A1/A2 exert virolytic activity likely by binding to phosphatidylethanolamine moieties within the viral membrane and by disrupting virus particle membrane integrity. Probably due to its specific mode of action, Laby A1/A2 antiviral activity was not affected by common resistance mutations to known RSV entry inhibitors. Taken together, Laby A1/A2 represent promising candidates for development as RSV inhibitors. Moreover, the cell-based screening system with primary RSV isolates described here should be useful to identify further antiviral agents.
Topics: Animals; Antiviral Agents; Bacteriocins; Cell Line; Cells, Cultured; Female; Humans; Lung; Mice; Mice, Inbred BALB C; Respiratory Syncytial Virus Infections; Respiratory Syncytial Virus, Human; Virus Internalization
PubMed: 32197980
DOI: 10.1016/j.antiviral.2020.104774