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Poultry Science Dec 2022Identification and analysis of the antimicrobial resistance of Pasteurella aerogenes (P. aerogenes) isolated from poultry. For susceptibility testing in accordance with...
Identification and analysis of the antimicrobial resistance of Pasteurella aerogenes (P. aerogenes) isolated from poultry. For susceptibility testing in accordance with the CLSI, plasmids were extracted via alkaline lysis and transferred by CaCl treatment. Genomic DNA of a representative P. aerogenes isolate was subjected to whole genome sequencing. CCCP was utilized to determine whether SF190908 contains an efflux pump. The bla gene was ligated with the pET-28 plasmid and transferred to Escherichia coli to verify it as an ESBL gene. SF190908 isolated from poultry was identified as P. aerogenes based upon biochemical and 16s rRNA results. The isolate showed high MIC values for eight antimicrobials. Sequencing results showed that the mobile element-mediated antimicrobial resistance gene cluster conferred antimicrobial resistance on the strain, and a single 5,105-bp plasmid, designated pRCAD0752PA-1, was isolated. Four antimicrobial resistance gene clusters were identified in the SF190908 chromosome; one antimicrobial resistance gene cluster carried the bla gene, which was verified as ESBL according to the CLSI and was detected in Pasteurellaceae for the first time, to the best of our knowledge. The efflux pump may confer antimicrobial resistance to SF190908. P. aerogenes isolated from poultry showed resistance genes encoded in mobile elements that confer multi-antimicrobial resistance to SF190908. The antimicrobial-resistant plasmid pRCAD0752PA-1 was isolated in SF190908 and conferred resistance to florfenicol. This study indicates an urgent need to increase efforts to monitor the spread of P. aerogenes multi-antimicrobial-resistant strains and plasmids, especially in newly discovered at-risk species such as poultry.
Topics: Animals; Pasteurella; Drug Resistance, Bacterial; RNA, Ribosomal, 16S; Chickens; Plasmids; Escherichia coli Infections; Escherichia coli; Anti-Bacterial Agents; beta-Lactamases; Microbial Sensitivity Tests
PubMed: 36274437
DOI: 10.1016/j.psj.2022.102207 -
Journal of Infection and Public Health 2019Nanoparticles (NPs) have become very important owing to their various uses. In this research, an environmentally friendly biological technique was used to synthesize...
INTRODUCTION
Nanoparticles (NPs) have become very important owing to their various uses. In this research, an environmentally friendly biological technique was used to synthesize silver nanoparticles with Coriandrum sativum L. The objective of this research to use the source for the fabrication of silver NPs from C. sativum L., and to check the activity of the fabricated silver NPs was determined versus a couple of gram negative and a couple of gram positive bacteria in the presence of antibiotic viz. gentamicin to judge their impact.
METHODOLOGY
A silver nitrate solution, which served as the reducing and capping agent, was mingled with coriander leaf extract. The solution's temperature and pH were maintained at 75°C and 8.6, respectively. The observed mean particle size (z-average) and polydispersity index were 390.2nm and 0.452, respectively. The synthesized Ag NPs were characterized using different techniques, including scanning electron microscopy (SEM), X-ray diffraction, and Fourier transmission infrared (FTIR) analysis. The globular shape of the silver nanoparticles was depicted in SEM illustrations.
RESULTS
XRD data revealed the mean size of the particles was 11.9nm. The FTIR analysis showed the existence of various functional groups, including CO and OH. When their antibacterial ability was tested, it was found that the fabricated Ag NPs inhibited Bacillus subtilis, Pasteurella multocida, Enterobacter aerogenes, and Staphylococcus aureus, with a greater effect against B. subtilis and P. multocida compared to E. aerogenes and S. aureus.
CONCLUSION
It has been concluded small silver NPs benefited from a higher surface area ratio, as shown by the results of experiments where smaller particles had a better bactericidal proficiency than large silver-based NPs. Silver-based NPs infiltrate bacterial cells, as well as interfere with their exterior membrane. Silver ions also have the potential to interact with bacterial DNA, inhibiting the reproductive system of the cell.
Topics: Anti-Infective Agents; Coriandrum; Gram-Negative Bacteria; Gram-Positive Bacteria; Metal Nanoparticles; Microscopy, Electron, Scanning; Plant Extracts; Silver; Spectroscopy, Fourier Transform Infrared; X-Ray Diffraction
PubMed: 30477919
DOI: 10.1016/j.jiph.2018.11.002 -
Scientific Reports Nov 2022The aim of this study was to analyse the microbicidal and microbiostatic activity of S. montana hydrolate L., the water-soluble fraction of the hydro-distillation...
The aim of this study was to analyse the microbicidal and microbiostatic activity of S. montana hydrolate L., the water-soluble fraction of the hydro-distillation process used to obtain the essential oil, on 14 Gram-positive and Gram-negative bacteria and a fungus of clinical interest. To consider whether this hydrolate is a more environmentally friendly alternative to traditional antibiotics, its effect on non-target microorganisms in the aquatic and terrestrial environment was analysed using natural soil and river microorganism communities, characterized through 16S rRNA gene sequencing. Results showed that S. montana hydrolate was especially effective (25% v/v concentration) against Pasteurella aerogenes, Streptococcus agalactiae and Acinetobacter baumannii (priority 1, WHO). It was also a microbicide for a further 7 bacterial strains and the fungus Candida albicans (50% v/v concentration). The river and soil communities exposed to the hydrolate showed a decrease in their growth, as well as a decrease in their ability to metabolize polymers and carbohydrates (soil microorganisms) and polymers, carboxylic and ketone acids (river microorganisms). Hydrolates could be an alternative to conventional antibiotics, but their impact on the environment must be taken into account.
Topics: Satureja; Anti-Bacterial Agents; Gram-Negative Bacteria; RNA, Ribosomal, 16S; Montana; Gram-Positive Bacteria; Bacteria; Anti-Infective Agents; Fungi; Soil; Polymers
PubMed: 36323748
DOI: 10.1038/s41598-022-22419-2 -
Antimicrobial Agents and Chemotherapy Oct 2001Tetracycline-resistant Pasteurella aerogenes isolates obtained from the intestinal tract of swine were investigated for their tet genes by PCR analysis and hybridization...
Tetracycline-resistant Pasteurella aerogenes isolates obtained from the intestinal tract of swine were investigated for their tet genes by PCR analysis and hybridization experiments. In contrast to Pasteurella isolates from the respiratory tract, tet(H) genes were detected in the chromosomal DNA of only 2 of the 24 isolates, one of which also carried two copies of a tet(B) gene. All other P. aerogenes isolates carried tet(B) genes, which are the predominant tet genes among Enterobacteriaceae. A single isolate harbored a tet(B) gene as part of a truncated Tn10 element on the 4.8-kb plasmid pPAT2. Comparative analysis of the pPAT2 sequence suggested that the Tn10 relic on plasmid pPAT2 is the result of several illegitimate recombination events. The remaining 21 P. aerogenes isolates carried one or two copies of the tet(B) gene in their chromosomal DNA. In the majority of the cases, these tet(B) genes were associated with copies of Tn10 as confirmed by their SfuI and BamHI hybridization patterns. No correlation between the number of tet gene copies and the MICs of tetracycline, doxycyline and minocycline was observed.
Topics: Animals; Bacterial Proteins; Chromosomes, Bacterial; Genotype; Intestines; Molecular Sequence Data; Pasteurella; Plasmids; Swine; Tetracycline Resistance
PubMed: 11557485
DOI: 10.1128/AAC.45.10.2885-2890.2001 -
Plants (Basel, Switzerland) May 2023The use of synergistic combinations between natural compounds and commercial antibiotics may be a good strategy to fight against microbial resistance, with fewer side...
The use of synergistic combinations between natural compounds and commercial antibiotics may be a good strategy to fight against microbial resistance, with fewer side effects on human, animal and environmental, health. The antimicrobial capacity of four compounds of plant origin (thymol and gallic, salicylic and gentisic acids) was analysed against 14 pathogenic bacteria. Thymol showed the best antimicrobial activity, with MICs ranging from 125 µg/mL (for , and ) to 250 µg/mL (for , , , , and . Combinations of thymol with eight widely used antibiotics were studied to identify combinations with synergistic effects. Thymol showed synergistic activity with chloramphenicol against (critical priority by the WHO), with streptomycin and gentamicin against (high priority by the WHO), and with streptomycin against , decreasing the MICs of these antibiotics by 75% to 87.5%. The kinetics of these synergies indicated that thymol alone at the synergy concentration had almost no effect on the maximum achievable population density and very little effect on the growth rate. However, in combination with antibiotics at the same concentration, it completely inhibited growth, confirming its role in facilitating the action of the antibiotic. The time-kill curves indicated that all the combinations with synergistic effects were mainly bactericidal.
PubMed: 37176927
DOI: 10.3390/plants12091868 -
Journal of Bacteriology Mar 1992Virtually complete 16S rRNA sequences were determined for 54 representative strains of species in the family Pasteurellaceae. Of these strains, 15 were Pasteurella, 16... (Comparative Study)
Comparative Study
Virtually complete 16S rRNA sequences were determined for 54 representative strains of species in the family Pasteurellaceae. Of these strains, 15 were Pasteurella, 16 were Actinobacillus, and 23 were Haemophilus. A phylogenetic tree was constructed based on sequence similarity, using the Neighbor-Joining method. Fifty-three of the strains fell within four large clusters. The first cluster included the type strains of Haemophilus influenzae, H. aegyptius, H. aphrophilus, H. haemolyticus, H. paraphrophilus, H. segnis, and Actinobacillus actinomycetemcomitans. This cluster also contained A. actinomycetemcomitans FDC Y4, ATCC 29522, ATCC 29523, and ATCC 29524 and H. aphrophilus NCTC 7901. The second cluster included the type strains of A. seminis and Pasteurella aerogenes and H. somnus OVCG 43826. The third cluster was composed of the type strains of Pasteurella multocida, P. anatis, P. avium, P. canis, P. dagmatis, P. gallinarum, P. langaa, P. stomatis, P. volantium, H. haemoglobinophilus, H. parasuis, H. paracuniculus, H. paragallinarum, and A. capsulatus. This cluster also contained Pasteurella species A CCUG 18782, Pasteurella species B CCUG 19974, Haemophilus taxon C CAPM 5111, H. parasuis type 5 Nagasaki, P. volantium (H. parainfluenzae) NCTC 4101, and P. trehalosi NCTC 10624. The fourth cluster included the type strains of Actinobacillus lignieresii, A. equuli, A. pleuropneumoniae, A. suis, A. ureae, H. parahaemolyticus, H. parainfluenzae, H. paraphrohaemolyticus, H. ducreyi, and P. haemolytica. This cluster also contained Actinobacillus species strain CCUG 19799 (Bisgaard taxon 11), A. suis ATCC 15557, H. ducreyi ATCC 27722 and HD 35000, Haemophilus minor group strain 202, and H. parainfluenzae ATCC 29242. The type strain of P. pneumotropica branched alone to form a fifth group. The branching of the Pasteurellaceae family tree was quite complex. The four major clusters contained multiple subclusters. The clusters contained both rapidly and slowly evolving strains (indicated by differing numbers of base changes incorporated into the 16S rRNA sequence relative to outgroup organisms). While the results presented a clear picture of the phylogenetic relationships, the complexity of the branching will make division of the family into genera a difficult and somewhat subjective task. We do not suggest any taxonomic changes at this time.
Topics: Base Sequence; DNA, Ribosomal; Molecular Sequence Data; Oligodeoxyribonucleotides; Pasteurellaceae; Phylogeny; RNA, Ribosomal, 16S; Sequence Alignment
PubMed: 1548238
DOI: 10.1128/jb.174.6.2002-2013.1992 -
Infection and Immunity Jan 2000Pasteurella aerogenes is known as a commensal bacterium or as an opportunistic pathogen, as well as a primary pathogen found to be involved in abortion cases of humans,...
Pasteurella aerogenes is known as a commensal bacterium or as an opportunistic pathogen, as well as a primary pathogen found to be involved in abortion cases of humans, swine, and other mammals. Using broad-range DNA probes for bacterial RTX toxin genes, we cloned and subsequently sequenced a new operon named paxCABD encoding the RTX toxin PaxA in P. aerogenes. The pax operon is organized analogous to the classical RTX operons containing the activator gene paxC upstream of the structural toxin gene paxA, which is followed by the secretion protein genes paxB and paxD. The highest sequence similarity of paxA with known RTX toxin genes is found with apxIIIA (82%). PaxA is structurally similar to ApxIIIA and also shows functional analogy to ApxIIIA, since it shows cohemolytic activity with the sphingomyelinase of Staphylococcus aureus, known as the CAMP effect, but is devoid of direct hemolytic activity. In addition, it shows to some extent immunological cross-reactions with ApxIIIA. P. aerogenes isolated from various specimens showed that the pax operon was present in about one-third of the strains. All of the pax-positive strains were specifically related to swine abortion cases or septicemia of newborn piglets. These strains were also shown to produce the PaxA toxin as determined by the CAMP phenomenon, whereas none of the pax-negative strains did. This indicated that the PaxA toxin is involved in the pathogenic potential of P. aerogenes. The examined P. aerogenes isolates were phylogenetically analyzed by 16S rRNA gene (rrs) sequencing in order to confirm their species. Only a small heterogeneity (<0.5%) was observed between the rrs genes of the strains originating from geographically distant farms and isolated at different times.
Topics: Abortion, Veterinary; Amino Acid Sequence; Animals; Animals, Newborn; Bacterial Proteins; Bacterial Toxins; Base Sequence; Cloning, Molecular; DNA Primers; DNA, Bacterial; Female; Genes, Bacterial; Hemolysin Proteins; Hemolysis; Humans; Molecular Sequence Data; Operon; Pasteurella; Pregnancy; RNA, Bacterial; RNA, Ribosomal, 16S; Sepsis; Swine; Swine Diseases; Virulence
PubMed: 10603361
DOI: 10.1128/IAI.68.1.6-12.2000 -
Journal of Bacteriology Dec 2015Na(+)-translocating NADH:quinone oxidoreductase (Na(+)-NQR) catalyzes electron transfer from NADH to ubiquinone in the bacterial respiratory chain, coupled with Na(+)...
UNLABELLED
Na(+)-translocating NADH:quinone oxidoreductase (Na(+)-NQR) catalyzes electron transfer from NADH to ubiquinone in the bacterial respiratory chain, coupled with Na(+) translocation across the membrane. Na(+)-NQR maturation involves covalent attachment of flavin mononucleotide (FMN) residues, catalyzed by flavin transferase encoded by the nqr-associated apbE gene. Analysis of complete bacterial genomes has revealed another putative gene (duf539, here renamed nqrM) that usually follows the apbE gene and is present only in Na(+)-NQR-containing bacteria. Expression of the Vibrio harveyi nqr operon alone or with the associated apbE gene in Escherichia coli, which lacks its own Na(+)-NQR, resulted in an enzyme incapable of Na(+)-dependent NADH or reduced nicotinamide hypoxanthine dinucleotide (dNADH) oxidation. However, fully functional Na(+)-NQR was restored when these genes were coexpressed with the V. harveyi nqrM gene. Furthermore, nqrM lesions in Klebsiella pneumoniae and V. harveyi prevented production of functional Na(+)-NQR, which could be recovered by an nqrM-containing plasmid. The Na(+)-NQR complex isolated from the nqrM-deficient strain of V. harveyi lacks several subunits, indicating that nqrM is necessary for Na(+)-NQR assembly. The protein product of the nqrM gene, NqrM, contains a single putative transmembrane α-helix and four conserved Cys residues. Mutating one of these residues (Cys33 in V. harveyi NqrM) to Ser completely prevented Na(+)-NQR maturation, whereas mutating any other Cys residue only decreased the yield of the mature protein. These findings identify NqrM as the second specific maturation factor of Na(+)-NQR in proteobacteria, which is presumably involved in the delivery of Fe to form the (Cys)4[Fe] center between subunits NqrD and NqrE.
IMPORTANCE
Na(+)-translocating NADH:quinone oxidoreductase complex (Na(+)-NQR) is a unique primary Na(+) pump believed to enhance the vitality of many bacteria, including important pathogens such as Vibrio cholerae, Vibrio parahaemolyticus, Haemophilus influenzae, Neisseria gonorrhoeae, Pasteurella multocida, Porphyromonas gingivalis, Enterobacter aerogenes, and Yersinia pestis. Production of Na(+)-NQR in bacteria requires Na(+)-NQR-specific maturation factors. We earlier identified one such factor (ApbE) that covalently attaches flavin residues to Na(+)-NQR. Here we identify the other protein factor, designated NqrM, and show that NqrM and ApbE suffice to produce functional Na(+)-NQR from the Vibrio harveyi nqr operon. NqrM may be involved in Fe delivery to a unique Cys4[Fe] center during Na(+)-NQR assembly. Besides highlighting Na(+)-NQR biogenesis, these findings suggest a novel drug target to combat Na(+)-NQR-containing bacteria.
Topics: Amino Acid Sequence; Bacterial Proteins; Biological Transport; Escherichia coli; Klebsiella pneumoniae; Molecular Sequence Data; NAD; Operon; Quinone Reductases; Quinones; Sequence Alignment; Sodium; Vibrio
PubMed: 26644436
DOI: 10.1128/JB.00757-15 -
BMC Microbiology Jan 2024Uterine infections, primarily caused by bacterial pathogens, pose a significant problem for dairy farmers worldwide, leading to poor reproductive performance and...
BACKGROUND
Uterine infections, primarily caused by bacterial pathogens, pose a significant problem for dairy farmers worldwide, leading to poor reproductive performance and economic losses. However, the bacteria responsible for uterine infections have not been adequately studied, nor has the antibiotic susceptibility of the causative bacteria been frequently tested in Ethiopia. This study aims to estimate the cumulative incidence of uterine infections in postpartum dairy cows, identify bacterial causes and determine antimicrobial susceptibility profile of the isolated bacteria.
METHODS
A prospective cohort study was conducted in which 236 cows from 74 dairy farms were monitored biweekly from calving to 90 days postpartum for metritis, endometritis and other disorders. Aseptic uterine swab samples were collected from 40 cows with uterine infections. The samples were cultured, and the isolated bacteria were tested for antimicrobial susceptibility using the disk diffusion method.
RESULTS
Out of 236 cows monitored during the postpartum phase, 45 (19.1%) were found to have contracted uterine infection. The cumulative incidence of metritis was 11.4% (n = 27), while the cumulative incidence of endometritis was 7.6% (n = 18). Of the 40 cultured swab samples, 29 (72.5%) had one or more bacteria isolated. The most commonly isolated bacteria were Escherichia coli (45%), coagulase-positive staphylococci (30%), and Klebsiella spp. (22.5%). Other bacterial spp, including Arcanobacterium pyogenes (12.5%), Fusobacterium spp. (12.5%), Enterobacter aerogenes (12.5%), coagulase-negative staphylococci (12.5%), Streptococcus spp. (7.5%), Salmonella spp, (5%) Proteus spp (5%) and Pasteurella spp (2.5%) were also isolated. All of the isolated bacteria demonstrated resistance to at least one of the antimicrobials tested. Multidrug resistance was observed in E. coli, Klebsiella spp., A. pyogenes, and Fusobacterium spp. Gentamicin was found to be the most effective antimicrobial against all bacteria tested, while tetracycline was the least effective of all.
CONCLUSION
The study found that a significant proportion of cows in the population were affected by uterine infections and the isolated bacteria developed resistance to several antimicrobials. The study emphasizes the need for responsible use of antimicrobials to prevent the emergence of antimicrobial resistance. It also highlights the importance of raising awareness among dairy farmers to avoid the indiscriminate use of antibiotics and its consequences.
Topics: Humans; Female; Cattle; Animals; Endometritis; Anti-Bacterial Agents; Incidence; Escherichia coli; Uterus; Prospective Studies; Coagulase; Ethiopia; Cattle Diseases; Drug Resistance, Bacterial; Bacteria; Postpartum Period
PubMed: 38172685
DOI: 10.1186/s12866-023-03160-w -
Applied Microbiology Dec 1970An experimental technique is presented for studying aerosols generated from lyophilized bacteria by using Escherichia coli B, Bacillus subtilis var. niger, Enterobacter...
An experimental technique is presented for studying aerosols generated from lyophilized bacteria by using Escherichia coli B, Bacillus subtilis var. niger, Enterobacter aerogenes, and Pasteurella tularensis. An aerosol generator capable of creating fine particle aerosols of small quantities (10 mg) of lyophilized powder under controlled conditions of exposure to the atmosphere is described. The physical properties of the aerosols are investigated as to the distribution of number of aerosol particles with particle size as well as to the distribution of number of bacteria with particle size. Biologically unstable vegetative cells were quantitated physically by using (14)C and Europium chelate stain as tracers, whereas the stable heat-shocked B. subtilis spores were assayed biologically. The physical persistence of the lyophilized B. subtilis aerosol is investigated as a function of size of spore-containing particles. The experimental result that physical persistence of the aerosol in a closed aerosol chamber increases as particle size is decreased is satisfactorily explained on the bases of electrostatic, gravitational, inertial, and diffusion forces operating to remove particles from the particular aerosol system. The net effect of these various forces is to provide, after a short time interval in the system (about 2 min), an aerosol of fine particles with enhanced physical stability. The dependence of physical stability of the aerosol on the species of organism and the nature of the suspending medium for lyophilization is indicated. Also, limitations and general applicability of both the technique and results are discussed.
Topics: Aerosols; Air Microbiology; Bacillus subtilis; Bacteria; Bacteriological Techniques; Carbon Isotopes; Enterobacter; Escherichia coli; Europium; Francisella tularensis; Freeze Drying; Physical Phenomena; Physics
PubMed: 4992657
DOI: 10.1128/am.20.6.927-934.1970