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Plants (Basel, Switzerland) Jan 2024One strategy to mitigate the emergence of bacterial resistance involves reducing antibiotic doses by combining them with natural products, such as trans-cinnamaldehyde...
One strategy to mitigate the emergence of bacterial resistance involves reducing antibiotic doses by combining them with natural products, such as trans-cinnamaldehyde (CIN). The objective of this research was to identify in vitro combinations (CIN + commercial antibiotic (ABX)) that decrease the minimum inhibitory concentration (MIC) of seven antibiotics against 14 different Gram-positive and Gram-negative pathogenic bacteria, most of them classified as ESKAPE. MIC values were measured for all compounds using the broth microdilution method. The effect of the combinations on these microorganisms was analyzed through the checkboard assay to determine the type of activity (synergy, antagonism, or addition). This analysis was complemented with a kinetic study of the synergistic combinations. Fifteen synergistic combinations were characterized for nine of the tested bacteria. CIN demonstrated effectiveness in reducing the MIC of chloramphenicol, streptomycin, amoxicillin, and erythromycin (94-98%) when tested on , , , and , respectively. The kinetic study revealed that when the substances were tested alone at the MIC concentration observed in the synergistic combination, bacterial growth was not inhibited. However, when CIN and the ABX, for which synergy was observed, were tested simultaneously in combination at these same concentrations, the bacterial growth inhibition was complete. This demonstrates the highly potent in vitro synergistic activity of CIN when combined with commercial ABXs. This finding could be particularly beneficial in livestock farming, as this sector witnesses the highest quantities of antimicrobial usage, contributing significantly to antimicrobial resistance issues. Further research focused on this natural compound is thus warranted for this reason.
PubMed: 38256746
DOI: 10.3390/plants13020192 -
Microbiology (Reading, England) Jan 1996Pasteurella multocida strain P1059 is a highly virulent bacterium which causes fowl cholera in turkeys and chickens. A genomic library of P. multocida P1059 DNA was... (Comparative Study)
Comparative Study
Pasteurella multocida strain P1059 is a highly virulent bacterium which causes fowl cholera in turkeys and chickens. A genomic library of P. multocida P1059 DNA was constructed using pUC19, expressed in Escherichia coli DH5 alpha, and screened with chicken antisera generated against P. multocida P1059. Twelve out of the 4100 clones screened were immunoreactive. Plasmids isolated from these twelve clones were transformed into E. coli CSR603 for maxicell analysis. Five proteins, with molecular masses of 34, 37, 43, 46 and 55 kDa, were expressed. Further work focused on the 43 kDa protein because it was expressed at levels detectable by SDS-PAGE and immunoblot analysis. The nucleotide sequence of the 1.8 kbp insert containing the gene encoding this protein was determined. The sequence contained three open reading frames (ORFs). The first ORF (ORF1) did not appear to code for any known protein. The second ORF (ORF2) encoded a protein of 403 amino acids (43,662 Da). The deduced amino acid sequence showed 77% identity (84% similarity) with the tryptophan synthase beta subunit (TrpB) of Salmonella typhimurium and Vibrio parahaemolyticus. The eight conserved regions of TrpB are observed in the P. multocida enzyme, including the conserved lysine (Lys-88) and consensus sequence (GGGSNA) implicated in pyridoxal phosphate binding. The expression and identity of the P. multocida TrpB were confirmed by complementation studies using E. coli W3110 tnaA2 trpB9578. The third ORF (ORF3) consisted of the first 77 nucleotides of the gene encoding the alpha-subunit of tryptophan synthase (trpA), and overlapped the 3'-end of trpB by 14 nucleotides. The deduced amino acid sequence of the 77 nucleotides of the P. multocida TrpA had 68% identity (92% similarity) with the analogous region of TrpA from Klebsiella aerogenes (K. pneumoniae).
Topics: Amino Acid Sequence; Antibodies, Bacterial; Antigens, Bacterial; Base Sequence; Escherichia coli; Genes, Bacterial; Genetic Complementation Test; Genomic Library; Molecular Sequence Data; Pasteurella multocida; Protein Conformation; Sequence Analysis, DNA; Sequence Homology, Amino Acid; Tryptophan Synthase
PubMed: 8581158
DOI: 10.1099/13500872-142-1-115 -
Epidemiology and Infection Dec 1988Six patients developed local infection after being bitten or gored by swine. Wounding was often deep and occurred characteristically on the posterior aspect of the...
Six patients developed local infection after being bitten or gored by swine. Wounding was often deep and occurred characteristically on the posterior aspect of the thigh. Severity of infection varied from simple wound infection with discharge and slough to cellulitis and abscess formation; pathogens included haemolytic streptococci, pasteurellae, Bacteroides sp., Proteus sp. and Escherichia coli and were usually isolated in mixed culture. A patient with Pasteurella aerogenes infection appears to be the first reported in England. A seventh patient developed Streptococcus milleri septicaemia after wounding himself while cutting teeth from piglets. It is suggested that a course of broad-spectrum antibiotics should be given as part of the initial treatment when patients present with the more severe pig bite injuries.
Topics: Adult; Animals; Bites and Stings; Humans; Male; Middle Aged; Swine; Wound Infection
PubMed: 3215292
DOI: 10.1017/s0950268800029514 -
Immunology Apr 1958Bacterial lipopolysaccharides and `O' somatic antigens usually require treatment with alkali for maximal adsorption on erythrocytes in preparation for indirect...
Bacterial lipopolysaccharides and `O' somatic antigens usually require treatment with alkali for maximal adsorption on erythrocytes in preparation for indirect haemagglutination. Although heating enhances sensitizing activity, owing partly to increasing dispersion, it is always less effective than alkali treatment. The presence of a protein component or of the chloroform soluble lipid `A' does not inhibit erythrocyte sensitizing activity and no change in sugar constituents has been detected as a result of treatment. The specific polysaccharide of , which contains no lipid, requires alkali treatment for activity; in this case the effect of alkali is to remove -acetate (4 per cent). The loss of weight on treatment is also 4 per cent and no other differences can be detected by examining the infrared-absorption spectra of treated and untreated samples. For other materials investigated a loss of -acetyl has been detected, except where alkali treatment is not required to elicit maximal activity, e.g. the lipopolysaccharide which contains about 50 per cent of lipid `A'. By reacetylation of alkali treated polysaccharides it has been shown that -acetyl residues inhibit adsorption on to erythrocytes, but in some instances higher fatty acids are also removed to some extent by treatment with alkali.
Topics: Adsorption; Erythrocytes; Humans; Polysaccharides; Polysaccharides, Bacterial
PubMed: 13538532
DOI: No ID Found -
Antimicrobial Agents and Chemotherapy Aug 1988The ROB-1 beta-lactamase, previously described in Haemophilus influenzae, has been found in the genus Pasteurella. In three bovine strains of Pasteurella multocida and...
The ROB-1 beta-lactamase, previously described in Haemophilus influenzae, has been found in the genus Pasteurella. In three bovine strains of Pasteurella multocida and Pasteurella haemolytica, ROB-1 production was determined by plasmids of 4.4 kilobases. In one porcine strain of Pasteurella aerogenes, the enzyme seems to be chromosomally encoded.
Topics: Animals; Autoradiography; Cattle; Chromosomes, Bacterial; DNA, Bacterial; Drug Resistance, Microbial; Electrophoresis, Agar Gel; Pasteurella; Plasmids; Swine; Transformation, Bacterial; beta-Lactamases
PubMed: 3263836
DOI: 10.1128/AAC.32.8.1282 -
Canadian Journal of Comparative... Aug 1964Sixteen cows were used in a series of experiments to test dose, route and frequency responses in the production of milk and serum agglutinins to a spectrum of 9 proven...
Production of Antibody in Mammary Gland of Pregnant, Non-Lactating and Lactating Cows, Evoked by Polyvalent Antigen with Reference to Dosage and Frequency of Immunization.
Sixteen cows were used in a series of experiments to test dose, route and frequency responses in the production of milk and serum agglutinins to a spectrum of 9 proven bovine pathogens. The bacterial species were: Pasteurella multocida (2 isolates), Escherichia coli, Staphylococcus aureus, Staphylococcus albus, Streptococcus sp., Corynebacterium sp., Salmonella enteriditis, and Aerobacter aerogenes. Primary immunizations were made either through the teat canal or intramuscularly. "Booster" injections were made through the teat canal. Agglutinins in the blood appeared only after a week or more. In the milk, titers were recorded in 1 or 2 days following primary immunization. Variation of titer in the blood and milk was somewhat independent. In all but 1 cow, antibody was produced against each organism in milk and blood serum. Udder inflammation was observed in the experiments when a 15-day interval separated immunizations. Inflammation was minimal in the experiments employing the 7-day interval of immunization. A positive Whiteside test was observed following most injections, even where no other clinical signs of reaction were seen. The findings are discussed in relation to the previous literature.
PubMed: 17649521
DOI: No ID Found