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Foods (Basel, Switzerland) Mar 2024The amount of macrolide (MAL) residues in aquatic products, including oleandomycin (OLD), erythromycin (ERM), clarithromycin (CLA), azithromycin (AZI), kitasamycin...
Dispersive Solid-Phase Extraction and Ultra-Performance Liquid Chromatography-Tandem Mass Spectrometry-A Rapid and Accurate Method for Detecting 10 Macrolide Residues in Aquatic Products.
The amount of macrolide (MAL) residues in aquatic products, including oleandomycin (OLD), erythromycin (ERM), clarithromycin (CLA), azithromycin (AZI), kitasamycin (KIT), josamycin (JOS), spiramycin (SPI), tilmicosin (TIL), tylosin (TYL), and roxithromycin (ROX), was determined using solid-phase extraction and ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The residues were extracted with 1% ammonia acetonitrile solution and purified by neutral alumina adsorption. Chromatographic separation was completed on an ACQUITY UPLC BEH C column with acetonitrile-0.1% formic acid aqueous solution as the mobile phase, and mass spectrometry detection was performed by multiple reaction monitoring scanning with the positive mode in an electrospray ion source (ESI). Five isotopically labeled compounds were used as internal standards for quality control purposes. The findings indicated that across the mass concentration span of 1.0-100 μg/L, there was a strong linear correlation ( > 0.99) between the concentration and instrumental response for the 10 MALs. The limit of detection of UPLC-MS/MS was 0.25-0.50 μg/kg, and the limit of quantitation was 0.5-1.0 μg/kg. The added recovery of blank matrix samples at standard gradient levels (1.0, 5.0, and 50.0 μg/kg) was 83.1-116.6%, and the intra-day precision and inter-day precisions were 3.7 and 13.8%, respectively. The method is simple and fast, with high accuracy and good repeatability, in line with the requirements for accurate qualitative and quantitative analysis of the residues for 10 MALs in aquatic products.
PubMed: 38540855
DOI: 10.3390/foods13060866 -
Diagnostic Microbiology and Infectious... May 2024Haemophilus influenzae is an important pathogen able to cause various forms of respiratory and invasive disease. To provide high sensitivity for detection, culture media...
Haemophilus influenzae is an important pathogen able to cause various forms of respiratory and invasive disease. To provide high sensitivity for detection, culture media must inhibit growth of residential flora from the respiratory tract. This study aimed to identify and compare the diagnostic and economic advantages of using bacitracin containing selective agar (SEL) or oleandomycin disk supplemented chocolate agar (CHOC). Growth and semi-quantitative abundance of H. influenzae and growth suppression of residential flora was prospectively assessed in a 28-week period. H. influenzae was identified in 164 (5 %) of all included samples: CHOC and SEL, CHOC only, and SEL only were positive in 95, 24, and 45 cases. Diagnostic superiority of SEL was primarily attributable to the results of throat swabs. However, on average, € 200 had to be spent for the detection of each additional isolate that was recovered only because of additional incubation on SEL.
Topics: Humans; Agar; Bacitracin; Haemophilus influenzae; Oleandomycin; Chocolate; Culture Media
PubMed: 38422664
DOI: 10.1016/j.diagmicrobio.2024.116203 -
The Science of the Total Environment Mar 2024The Urban Wastewater Treatment Directive recent draft issued last October 2022 pays attention to contaminants of emerging concern including organic micropollutants...
The Urban Wastewater Treatment Directive recent draft issued last October 2022 pays attention to contaminants of emerging concern including organic micropollutants (OMPs) and requires the removal of some of them at large urban wastewater treatment plants (WWTPs) calling for their upgrading. Many investigations to date have reported the occurrence of a vast group of OMPs in the influent and many technologies have been tested for their removal at a lab- or pilot-scale. Moreover, it is well-known that hospital wastewater (HWW) contains specific OMPs at high concentration and therefore its management and treatment deserves attention. In this study, a 1-year investigation was carried out at a full-scale membrane bioreactor (MBR) treating mainly HWW. To promote the removal of OMPs, powdered activated carbon (PAC) was added to the bioreactor at 0.1 g/L and 0.2 g/L which resulted in the MBR operating as a hybrid MBR. Its performance was tested for 232 target and 90 non-target OMPs, analyzed by UHPLC-QTOF-MS using a direct injection method. A new methodology was defined to select the key compounds in order to evaluate the performance of the treatments. It was based on their frequency, occurrence, persistence to removal, bioaccumulation and toxicity. Finally, an environmental risk assessment of the OMP residues was conducted by means of the risk quotient approach. The results indicate that PAC addition increased the removal of most of the key OMPs (e.g., sulfamethoxazole, diclofenac, lidocaine) and OMP classes (e.g., antibiotics, psychiatric drugs and stimulants) with the highest loads in the WWTP influent. The hybrid MBR also reduced the risk in the receiving water as the PAC dosage increased mainly for spiramycin, lorazepam, oleandomycin. Finally, uncertainties and issues related to the investigation being carried out at full-scale under real conditions are discussed.
Topics: Wastewater; Waste Disposal, Fluid; Water Pollutants, Chemical; Adsorption; Charcoal; Water Purification; Bioreactors; Powders
PubMed: 38190908
DOI: 10.1016/j.scitotenv.2023.169848 -
Saudi Journal of Biological Sciences Oct 2023The study aimed to reveal the structure and function of phageome existing in soil rhizobiome of in order to detect accidentally-packaged bacterial genes that encode...
The study aimed to reveal the structure and function of phageome existing in soil rhizobiome of in order to detect accidentally-packaged bacterial genes that encode Carbohydrate-Active enZymes (or CAZymes) and those that confer antibiotic resistance (e.g., antibiotic resistance genes or ARGs). Highly abundant genes were shown to mainly exist in members of the genera , , and . Enriched CAZymes belong to glycoside hydrolase families GH4, GH6, GH12, GH15 and GH43 and mainly function in D-glucose biosynthesis via 10 biochemical passages. Another enriched CAZyme, e.g., alpha-galactosidase, of the GH4 family is responsible for the wealth of different carbohydrate forms in rhizospheric soil sink of . ARGs of this phageome include the and genes that participate in the "antibiotic efflux pump" resistance mechanism, the mutant gene that participates in the "antibiotic target alteration" mechanism and the , , and genes that participate in the "antibiotic inactivation" mechanism. It is claimed that the genera , which harbors phages with and mutant genes, and , which harbors phages with and genes, are approaching multidrug resistance via newly disseminating phages. These ARGs inhibit many antibiotics including oleandomycin, tetracycline, rifampin and aminoglycoside. The study highlights the possibility of accidental packaging of these ARGs in soil phageome and the risk of their horizontal transfer to human gut pathogens through the food chain as detrimental impacts of soil phageome of . The study also emphasizes the beneficial impacts of phageome on soil microbiome and plant interacting in storing carbohydrates in the soil sink for use by the two entities upon carbohydrate deprivation.
PubMed: 37680975
DOI: 10.1016/j.sjbs.2023.103789 -
PloS One 2023Lactic acid bacteria are known to produce numerous antibacterial metabolites that are active against various pathogenic microbes. In this study, bioactive metabolites...
Lactic acid bacteria are known to produce numerous antibacterial metabolites that are active against various pathogenic microbes. In this study, bioactive metabolites from the cell free supernatant of Loigolactobacillus coryniformis BCH-4 were obtained by liquid-liquid extraction, using ethyl acetate, followed by fractionation, using silica gel column chromatography. The collected F23 fraction effectively inhibited the growth of pathogenic bacteria (Escherichia coli, Bacillus cereus, and Staphylococcus aureus) by observing the minimum inhibitory concentration (MIC) and minimum bactericidal concentrations (MBC). The evaluated values of MIC were 15.6 ± 0.34, 3.9 ± 0.59, and 31.2 ± 0.67 μg/mL and MBC were 15.6 ± 0.98, 7.8 ± 0.45, and 62.5 ± 0.23 μg/mL respectively, against the above-mentioned pathogenic bacteria. The concentration of F23 fraction was varying from 1000 to 1.9 μg/mL. Furthermore, the fraction also exhibited sustainable biofilm inhibition. Using the Electrospray Ionization Mass Spectrometry (ESI-MS/MS), the metabolites present in the bioactive fraction (F23), were identified as phthalic acid, myristic acid, mangiferin, 16-hydroxylpalmatic acid, apigenin, and oleandomycin. By using in silico approach, docking analysis showed good interaction of identified metabolites and receptor proteins of pathogenic bacteria. The present study suggested Loigolactobacillus coryniformis BCH-4, as a promising source of natural bioactive metabolites which may receive great benefit as potential sources of drugs in the pharmacological sector.
Topics: Humans; Tandem Mass Spectrometry; Anti-Bacterial Agents; Staphylococcus aureus; Bacillus cereus; Microbial Sensitivity Tests
PubMed: 37561679
DOI: 10.1371/journal.pone.0289723 -
Frontiers in Microbiology 2023The study aims to describe phageome of soil rhizosphere of in terms of the genes encoding CAZymes and other KEGG enzymes.
INTRODUCTION
The study aims to describe phageome of soil rhizosphere of in terms of the genes encoding CAZymes and other KEGG enzymes.
METHODS
Genes of the rhizospheric virome of the wild plant species were investigated for their ability to encode useful CAZymes and other KEGG (Kyoto Encyclopedia of Genes and Genomes) enzymes and to resist antibiotic resistance genes (ARGs) in the soil.
RESULTS
Abundance of these genes was higher in the rhizospheric microbiome than in the bulk soil. Detected viral families include the plant viral family Potyviridae as well as the tailed bacteriophages of class Caudoviricetes that are mainly associated with bacterial genera and . Viral CAZymes in this soil mainly belong to glycoside hydrolase (GH) families GH43 and GH23. Some of these CAZymes participate in a KEGG pathway with actions included debranching and degradation of hemicellulose. Other actions include biosynthesizing biopolymer of the bacterial cell wall and the layered cell wall structure of peptidoglycan. Other CAZymes promote plant physiological activities such as cell-cell recognition, embryogenesis and programmed cell death (PCD). Enzymes of other pathways help reduce the level of soil HO and participate in the biosynthesis of glycine, malate, isoprenoids, as well as isoprene that protects plant from heat stress. Other enzymes act in promoting both the permeability of bacterial peroxisome membrane and carbon fixation in plants. Some enzymes participate in a balanced supply of dNTPs, successful DNA replication and mismatch repair during bacterial cell division. They also catalyze the release of signal peptides from bacterial membrane prolipoproteins. Phages with the most highly abundant antibiotic resistance genes (ARGs) transduce species of bacterial genera , and . Abundant mechanisms of antibiotic resistance in the rhizosphere include "antibiotic efflux pump" for ARGs , and , "antibiotic target alteration" for , and "antibiotic inactivation" for .
DISCUSSION
These ARGs can act synergistically to inhibit several antibiotics including tetracycline, penam, cephalosporin, rifamycins, aminocoumarin, and oleandomycin. The study highlighted the issue of horizontal transfer of ARGs to clinical isolates and human gut microbiome.
PubMed: 37260683
DOI: 10.3389/fmicb.2023.1166148 -
Frontiers in Microbiology 2022Antimicrobial resistance (AMR) is a serious threat to public health globally; it is estimated that AMR bacteria caused 1.27 million deaths in 2019, and this is set to...
Antimicrobial resistance (AMR) is a serious threat to public health globally; it is estimated that AMR bacteria caused 1.27 million deaths in 2019, and this is set to rise to 10 million deaths annually. Agricultural and soil environments act as antimicrobial resistance gene (ARG) reservoirs, operating as a link between different ecosystems and enabling the mixing and dissemination of resistance genes. Due to the close interactions between humans and agricultural environments, these AMR gene reservoirs are a major risk to both human and animal health. In this study, we aimed to identify the resistance gene reservoirs present in four microbiomes: poultry, ruminant, swine gastrointestinal (GI) tracts coupled with those from soil. This large study brings together every poultry, swine, ruminant, and soil shotgun metagenomic sequence available on the NCBI sequence read archive for the first time. We use the ResFinder database to identify acquired antimicrobial resistance genes in over 5,800 metagenomes. ARGs were diverse and widespread within the metagenomes, with 235, 101, 167, and 182 different resistance genes identified in the poultry, ruminant, swine, and soil microbiomes, respectively. The tetracycline resistance genes were the most widespread in the livestock GI microbiomes, including (W)_1, (Q)_1, (O)_1, and (44)_1. The (W)_1 resistance gene was found in 99% of livestock GI tract microbiomes, while (Q)_1 was identified in 93%, (O)_1 in 82%, and finally (44)_1 in 69%. Metatranscriptomic analysis confirmed these genes were "real" and expressed in one or more of the livestock GI tract microbiomes, with (40)_1 and (O)_1 expressed in all three livestock microbiomes. In soil, the most abundant ARG was the oleandomycin resistance gene, (B)_1. A total of 55 resistance genes were shared by the four microbiomes, with 11 ARGs actively expressed in two or more microbiomes. By using all available metagenomes we were able to mine a large number of samples and describe resistomes in 37 countries. This study provides a global insight into the diverse and abundant antimicrobial resistance gene reservoirs present in both livestock and soil microbiomes.
PubMed: 35875563
DOI: 10.3389/fmicb.2022.897905 -
Frontiers in Cellular and Infection... 2021Boromycin is a boron-containing macrolide antibiotic produced by with potent activity against certain viruses, Gram-positive bacteria and protozoan parasites. Most...
Boromycin is a boron-containing macrolide antibiotic produced by with potent activity against certain viruses, Gram-positive bacteria and protozoan parasites. Most antimalarial antibiotics affect plasmodial organelles of prokaryotic origin and have a relatively slow onset of action. They are used for malaria prophylaxis and for the treatment of malaria when combined to a fast-acting drug. Despite the success of artemisinin combination therapies, the current gold standard treatment, new alternatives are constantly needed due to the ability of malaria parasites to become resistant to almost all drugs that are in heavy clinical use. antiplasmodial activity screens of tetracyclines (omadacycline, sarecycline, methacycline, demeclocycline, lymecycline, meclocycline), macrolides (oleandomycin, boromycin, josamycin, troleandomycin), and control drugs (chloroquine, clindamycin, doxycycline, minocycline, eravacycline) revealed boromycin as highly potent against and the zoonotic . In contrast to tetracyclines, boromycin rapidly killed asexual stages of both species already at low concentrations (~ 1 nM) including multidrug resistant strains (Dd2, K1, 7G8). In addition, boromycin was active against stage V gametocytes at a low nanomolar range (IC: 8.5 ± 3.6 nM). Assessment of the mode of action excluded the apicoplast as the main target. Although there was an ionophoric activity on potassium channels, the effect was too low to explain the drug´s antiplasmodial activity. Boromycin is a promising antimalarial candidate with activity against multiple life cycle stages of the parasite.
Topics: Animals; Anti-Bacterial Agents; Antimalarials; Borates; Malaria, Falciparum; Plasmodium falciparum
PubMed: 35096650
DOI: 10.3389/fcimb.2021.802294 -
The FEBS Journal Jan 2022The translocon SecYEG and the associated ATPase SecA form the primary protein secretion system in the cytoplasmic membrane of bacteria. The secretion is essentially...
The translocon SecYEG and the associated ATPase SecA form the primary protein secretion system in the cytoplasmic membrane of bacteria. The secretion is essentially dependent on the surrounding lipids, but the mechanistic understanding of their role in SecA : SecYEG activity is sparse. Here, we reveal that the unsaturated fatty acids (UFAs) of the membrane phospholipids, including tetraoleoyl-cardiolipin, stimulate SecA : SecYEG-mediated protein translocation up to ten-fold. Biophysical analysis and molecular dynamics simulations show that UFAs increase the area per lipid and cause loose packing of lipid head groups, where the N-terminal amphipathic helix of SecA docks. While UFAs do not affect the translocon folding, they promote SecA binding to the membrane, and the effect is enhanced up to fivefold at elevated ionic strength. Tight SecA : lipid interactions convert into the augmented translocation. Our results identify the fatty acid structure as a notable factor in SecA : SecYEG activity, which may be crucial for protein secretion in bacteria, which actively change their membrane composition in response to their habitat.
Topics: Adenosine Triphosphatases; Cardiolipins; Escherichia coli; Escherichia coli Proteins; Fatty Acids, Unsaturated; Lipid Bilayers; Membrane Proteins; Oleandomycin; Phospholipids; Protein Transport; SEC Translocation Channels; SecA Proteins; Tetracycline
PubMed: 34312977
DOI: 10.1111/febs.16140 -
Biomolecules Oct 2020The cytochrome P450 OleP catalyzes the epoxidation of aliphatic carbons on both the aglycone 8.8a-deoxyoleandolide (DEO) and the monoglycosylated...
The cytochrome P450 OleP catalyzes the epoxidation of aliphatic carbons on both the aglycone 8.8a-deoxyoleandolide (DEO) and the monoglycosylated L-olivosyl-8.8a-deoxyoleandolide (L-O-DEO) intermediates of oleandomycin biosynthesis. We investigated the substrate versatility of the enzyme. X-ray and equilibrium binding data show that the aglycone DEO loosely fits the OleP active site, triggering the closure that prepares it for catalysis only on a minor population of enzyme. The open-to-closed state transition allows solvent molecules to accumulate in a cavity that forms upon closure, mediating protein-substrate interactions. docking of the monoglycosylated L-O-DEO in the closed OleP-DEO structure shows that the L-olivosyl moiety can be hosted in the same cavity, replacing solvent molecules and directly contacting structural elements involved in the transition. X-ray structures of aglycone-bound OleP in the presence of L-rhamnose confirm the cavity as a potential site for sugar binding. All considered, we propose L-O-DEO as the optimal substrate of OleP, the L-olivosyl moiety possibly representing the molecular wedge that triggers a more efficient structural response upon substrate binding, favoring and stabilizing the enzyme closure before catalysis. OleP substrate versatility is supported by structural solvent molecules that compensate for the absence of a glycosyl unit when the aglycone is bound.
Topics: Catalysis; Crystallography, X-Ray; Cytochrome P-450 Enzyme System; Lactones; Protein Domains; Rhamnose; Structure-Activity Relationship; Substrate Specificity
PubMed: 33036250
DOI: 10.3390/biom10101411