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Journal of Dairy Science Nov 2023Staphylococcus chromogenes and Staphylococcus simulans are commonly found in intramammary infections (IMI) associated with bovine subclinical mastitis, but little is...
Staphylococcus chromogenes and Staphylococcus simulans are commonly found in intramammary infections (IMI) associated with bovine subclinical mastitis, but little is known about genotypic variation and relatedness within species. This includes knowledge about genes encoding antimicrobial resistance (AMR) and potential virulence factors (pVF). The aim of this study was therefore to investigate these aspects by whole-genome sequencing of milk isolates from Swedish dairy cows with subclinical mastitis in an observational study. We also wanted to study if specific genotypes were associated with persistent IMI and the inflammatory response at udder quarter level. In total, 105 and 118 isolates of S. chromogenes and S. simulans, respectively, were included. Isolates were characterized using a 7-locus multilocus sequence typing (7-MLST), core genome analysis and in-silico analysis of AMR and pVF genes. Forty-seven sequence types (ST) and 7 core genome clusters of S. chromogenes were identified, and the most common ST were ST-6 and ST-109, both belonging to cluster VII. A 7-locus MLST scheme for S. simulans was not available, but 3 core genome clusters and 5 subclusters were described. Overall, substantial variation in ST and clusters among cows and herds were found in both species. Some ST of S. chromogenes were found in several herds, indicating spread between herds. Moreover, within-herd spread of the same genotype was observed for both species. Only a few AMR genes [blaZ, strpS194, vga(A)] were detected in a limited number of isolates, with the exception of blaZ coding for β-lactamase, which was identified in 22% of the isolates of S. chromogenes with ST-19, ST-102, and ST-103 more commonly carrying this gene compared with other ST. However, the blaZ gene was not identified in S. simulans. The average total number of pVF detected per isolate was similar in S. chromogenes (n = 30) and S. simulans (n = 33), but some variation in total numbers and presence of specific pVF or functional groups of pVF, was shown between ST/clusters within species. Differences in inflammatory response and potentially in persistent IMI at udder quarter level were found between S. chromogenes subtypes but not between S. simulans subtypes. In conclusion, the results from the present study generates new insight into the epidemiology of bovine S. chromogenes and S. simulans IMI, which can have implications for future prevention and antimicrobial treatment of infections related to these species.
PubMed: 37641317
DOI: 10.3168/jds.2023-23523 -
Probiotics and Antimicrobial Proteins Aug 2023Bacteriocins are antimicrobial peptides produced by bacteria. This study aimed to in silico analyze the presence of bacteriocin gene clusters (BGCs) among the genomes of...
Bacteriocins are antimicrobial peptides produced by bacteria. This study aimed to in silico analyze the presence of bacteriocin gene clusters (BGCs) among the genomes of 22 commensal Staphylococcus isolates from different origins (environment/human/food/pet/wild animals) previously identified as bacteriocin producers. The resistome and plasmidome were studied in all isolates. Five types of BGC were detected in 18 genomes of the 22 bacteriocin-producing staphylococci included in this study: class I (Lanthipeptides), class II, circular bacteriocins, the non-ribosomal-peptide lugdunin and the thiopeptide micrococcin P1 (MP1). A high frequency of lanthipeptides was detected in this collection: BGC variants of BSA, bacCH91, and epilancin15X were identified in two Staphylococcus aureus and one Staphylococcus warneri isolates from food and wild animals. Moreover, two potentially new lanthipeptide-like BGCs with no identity to database entries were found in Staphylococcus epidermidis and Staphylococcus simulans from food and wild animal, respectively. Interestingly, four isolates (one S. aureus and one Staphylococcus hominis, environmental origin; two Staphylococcus sciuri, food) carried the MP1 BGC with differences to those previously described. On the other hand, seven of the 22 genomes (~32%) lacked known genes related with antibiotic or disinfectant-acquired resistance mechanisms. Moreover, the potential carriage of plasmids was evaluated, and several Rep-proteins were identified (~73% of strains). In conclusion, a wide variety of BGCs has been observed among the 22 genomes, and an interesting relationship between related Staphylococcus species and the type of bacteriocin has been revealed. Therefore, bacteriocin-producing Staphylococcus and especially coagulase-negative staphylococci (CoNS) can be considered good candidates as a source of novel bacteriocins.
PubMed: 37632676
DOI: 10.1007/s12602-023-10119-w -
Drug Metabolism and Personalized Therapy Dec 2023Antibiotic resistance is rising, prompting innovative strategies for eradicating the epidemic. This study investigated the antibacterial properties of the leaves of a...
OBJECTIVES
Antibiotic resistance is rising, prompting innovative strategies for eradicating the epidemic. This study investigated the antibacterial properties of the leaves of a widely used medicinal plant, .
METHODS
The plant's polar (water, methanol) and non-polar (hexane) extracts were tested against several different bacterial strains using the disc diffusion technique.
RESULTS
In a study, it was found that the water extract had the greatest inhibitory effect on and , with minimum inhibitory concentrations of 16.444 and 19.315 g/mL, respectively. Gram-negative strains were more susceptible to plant extracts than Gram-positive strains. The phytochemical analysis indicated the presence of secondary metabolites such as alkaloids, saponins, flavonoids, tannins, and steroids, where absorbance was recorded at 415 nm. The water extract had the highest amount of phenolics, with a total phenolic content of 53.92 0.47 mg and a total flavonoid content of 7.25 0.08 mg. Results suggest that the extract may have potential therapeutic applications for antimicrobial properties.
CONCLUSIONS
The study concluded that the extract's phenolic group of secondary metabolites were responsible for its antibacterial activity. The study highlights as a promising source for discovering new and effective antibacterial compounds.
Topics: Humans; Plants, Medicinal; Plant Extracts; Justicia; Anti-Infective Agents; Anti-Bacterial Agents; Flavonoids; Water; Phenols; Plant Leaves
PubMed: 37381682
DOI: 10.1515/dmpt-2023-0012 -
Food Chemistry Nov 2023In this study, crude peptides from fermented sausages inoculated with Lactobacillus plantarum CD101 and Staphylococcus simulans NJ201 were initially separated by...
In this study, crude peptides from fermented sausages inoculated with Lactobacillus plantarum CD101 and Staphylococcus simulans NJ201 were initially separated by ultrafiltration and molecular-sieve chromatography. The obtained fractions with high 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and ferric-reducing antioxidant power values (MWCO-1 and fraction A) were used in Caco-2 cells to evaluate their cytoprotective effect on oxidative damage triggered by HO. MWCO-1 and A showed slight cytotoxicity. Increased glutathione peroxidase, catalase, and superoxide dismutase activities and decreased malondialdehyde content were observed in the peptide-treated groups. Fraction A was further purified using reversed high-performance liquid chromatography. Eighty potential antioxidant peptides were identified by liquid chromatography with tandem mass spectrometry, and fourteen antioxidant peptides were synthesized. SDEEVEH and FAGDDAPR showed strong DPPH radical scavenging activity, whereas ALELDSNLYR and QEYDESGPSIVHR presented strong ABTS scavenging activity. These peptides might have great potential for food and pharmacological applications.
Topics: Animals; Humans; Swine; Antioxidants; Caco-2 Cells; Hydrogen Peroxide; Pork Meat; Red Meat; Peptides
PubMed: 37331140
DOI: 10.1016/j.foodchem.2023.136566 -
Probiotics and Antimicrobial Proteins Jun 2024Cholangiocarcinoma (CCA), a bile duct cancer with a high mortality rate, has a poor prognosis due to its highly invasive and drug-resistant phenotypes. More effective...
Cholangiocarcinoma (CCA), a bile duct cancer with a high mortality rate, has a poor prognosis due to its highly invasive and drug-resistant phenotypes. More effective and selective therapies are urgently needed. Bacteriocins are broad-spectrum antimicrobial peptides/proteins produced by bacterial strains to compete with other bacteria. Recent studies have reported that bacteriocins exhibit anticancer properties against various cancer cell lines with minimal toxicity toward normal cells. In this study, two types of recombinant bacteriocins, rhamnosin from probiotic Lacticaseibacillus rhamnosus and lysostaphin from Staphylococcus simulans, were highly produced in Escherichia coli and subsequently purified via immobilized-Ni affinity chromatography. When their anticancer activity was investigated against CCA cell lines, both rhamnosin and lysostaphin were found capable of inhibiting the growth of CCA cell lines in a dose-dependent fashion but were less toxic toward a normal cholangiocyte cell line. Rhamnosin and lysostaphin as single treatments could suppress the growth of gemcitabine-resistant cell lines to the same extent as or more than they suppressed the parental counterparts. A combination of both bacteriocins more strongly inhibited growth and enhanced cell apoptosis in both parental and gemcitabine-resistant cells partly through the increased expression of the proapoptotic genes BAX, and caspase-3, -8, and -9. In conclusion, this is the first report to demonstrate an anticancer property of rhamnosin and lysostaphin. Using these bacteriocins as single agents or in combination would be effective against drug-resistant CCA.
Topics: Humans; Gemcitabine; Cell Line, Tumor; Deoxycytidine; Cholangiocarcinoma; Bacteriocins; Lysostaphin; Drug Synergism; Drug Resistance, Neoplasm; Antineoplastic Agents; Lacticaseibacillus rhamnosus; Recombinant Proteins; Bile Duct Neoplasms; Apoptosis
PubMed: 37294416
DOI: 10.1007/s12602-023-10096-0 -
Journal of Dairy Science Nov 2023Subclinical mastitis can be common among freshly calved heifers (FCH), but the prevalence differs between herds, possibly due to variation in risk factors. The aims of...
Subclinical mastitis can be common among freshly calved heifers (FCH), but the prevalence differs between herds, possibly due to variation in risk factors. The aims of this observational study were to identify differences in occurrence of intramammary infection (IMI) in FCH between herds with documented good or poorer first-parity udder health based on cow somatic cell count (CSCC) in early lactation, and to study herd differences in animal factors important for udder health, such as udder and hock skin lesions and animal cleanliness. Three groups of herds were included: those with high proportions of FCH with low CSCC (≤75,000 cells/mL) at the first 2 milk recordings after calving (LL), herds with high proportions of FCH with high CSCC (>100,000 cells/mL) at the first and low CSCC at the second recording (HL), and herds with high proportions of FCH with high CSCC at both recordings (HH). Thirty-nine herds (13 LL, 11 HL, 15 HH) were visited 3 times during a 12-mo period for observation of cleanliness and hock lesions, and sampling of udder and teat skin using swab cloths of milk-fed calves, early-pregnant heifers, and late-pregnant heifers. In 25 (9 LL, 9 HL, 7 HH) udder quarter samples from colostrum and milk on d 3 to 4 after calving were taken by the farmers from FCH during one year. The farmers also provided information on calving (individual or group), use of restraint and oxytocin at milking, and presence of teat and udder skin lesions. Bacterial growth in swab samples and quarter samples was investigated by culturing, and a selection of isolates was genotyped using whole-genome sequencing. Cleanliness, hock and udder skin lesions other than udder-thigh dermatitis, and growth of bacteria in swab samples did not differ between herd groups. It was more common that FCH from LL herds, compared with FCH in HH and HL herds, calved in a group of animals. Use of restraint at milking was more common in LL herds than in HH herds, whereas presence of udder-thigh dermatitis was lowest in LL herds. Specific infection was found in 14% of 5,593 quarter samples from 722 FCH. The most common IMI was Staphylococcus chromogenes. Growth of Staphylococcus simulans was more common in HH than in LL and HL herds. In colostrum samples, Staphylococcus haemolyticus was more common in HL and HH than in LL herds. The proportion of quarters with the same specific infection at both samplings was higher in HH than in LL herds and tended to be higher in HH than in HL herds. The proportion of quarters with Staph. chromogenes IMI at both samplings tended to differ between herd groups and was highest in HH herds. Whole-genome sequencing found the same sequence type of Staph. chromogenes and Staphylococcus aureus in both samples in almost all quarters with the same infection at both samplings. The differences in IMI between herd groups were in line with the higher somatic cell count in HH herds. The reasons for the predominance of Staph. chromogenes IMI in FCH need further studies.
PubMed: 37210369
DOI: 10.3168/jds.2022-22995 -
Iranian Journal of Microbiology Apr 2023secretes an antimicrobial compound called lysostaphin, which has bactericidal properties. It destroys staphylococci through the hydrolysis of peptidoglycan in the cell...
BACKGROUND AND OBJECTIVES
secretes an antimicrobial compound called lysostaphin, which has bactericidal properties. It destroys staphylococci through the hydrolysis of peptidoglycan in the cell wall. Therefore, this unique property indicates the high ability of lysostaphin in the treatment of staphylococcal infections and is considered as an anti-staphylococcal agent.
MATERIALS AND METHODS
BL21 (DE3) competent cells were transformed with pET32a-lysostaphin clone and induced by isopropyl-β-D-thio-galactoside (IPTG). The recombinant protein was purified by affinity chromatography. Recombinant lysostaphin -A-based ointment was used for external wound healing in animal model. activity of ointment was evaluated by clinical evidences and cytological microscopic assessment.
RESULTS
Our results showed the recombinant protein was produced exactly. The results of checkerboard tests showed MIC, MBC and antibacterial activity test an acute reduction of cell viability during the use of lysostaphin, and SEM results approved the intense wrecking effects of lysostaphin in combination on bacterial cells. Macroscopic findings and microscopic data showed that the recombinant lysostaphin ointment was effective on excisional wound healing.
CONCLUSION
Our findings proved that the recombinant lysostaphin ointment was effective on wound healing due to infection.
PubMed: 37193239
DOI: 10.18502/ijm.v15i2.12476 -
Biochimica Et Biophysica Acta.... Aug 2023Antimicrobial peptides (AMPs) commonly target bacterial membranes and show broad-spectrum activity against microorganisms. In this research we used three AMPs (nisin,...
Antimicrobial peptides (AMPs) commonly target bacterial membranes and show broad-spectrum activity against microorganisms. In this research we used three AMPs (nisin, epilancin 15×, [R4L10]-teixobactin) and tested their membrane effects towards three strains (Staphylococcus simulans, Micrococcus flavus, Bacillus megaterium) in relation with their antibacterial activity. We describe fluorescence and luminescence-based assays to measure effects on membrane potential, intracellular pH, membrane permeabilization and intracellular ATP levels. The results show that our control peptide, nisin, performed mostly as expected in view of its targeted pore-forming activity, with fast killing kinetics that coincided with severe membrane permeabilization in all three strains. However, the mechanisms of action of both Epilancin 15× as well as [R4L10]-teixobactin appeared to depend strongly on the bacterium tested. In certain specific combinations of assay, peptide and bacterium, deviations from the general picture were observed. This was even the case for nisin, indicating the importance of using multiple assays and bacteria for mode of action studies to be able to draw proper conclusions on the mode of action of AMPs.
Topics: Nisin; Antimicrobial Peptides; Antimicrobial Cationic Peptides; Bacteria; Anti-Bacterial Agents
PubMed: 37100361
DOI: 10.1016/j.bbamem.2023.184160 -
Journal of Microbiology and... Jun 2023Microbial biofilms are resilient, immune-evasive, often antibiotic-resistant health challenges, and increasingly the target for research into novel therapeutic...
Microbial biofilms are resilient, immune-evasive, often antibiotic-resistant health challenges, and increasingly the target for research into novel therapeutic strategies. We evaluated the effects of a nutraceutical enzyme and botanical blend (NEBB) on established biofilm. Five microbial strains with known implications in chronic human illnesses were tested: , and . The strains were allowed to form biofilm in vitro. Biofilm cultures were treated with NEBB containing enzymes targeted at lipids, proteins, and sugars, also containing the mucolytic compound N-acetyl cysteine, along with antimicrobial extracts from cranberry, berberine, rosemary, and peppermint. The post-treatment biofilm mass was evaluated by crystal-violet staining, and metabolic activity was measured using the MTT assay. Average biofilm mass and metabolic activity for NEBB-treated biofilms were compared to the average of untreated control cultures. Treatment of established biofilm with NEBB resulted in biofilm-disruption, involving significant reductions in biofilm mass and metabolic activity for and both species. For , we observed reduced biofilm mass, but the remaining residual biofilm showed a mild increase in metabolic activity, suggesting a shift from metabolically quiescent, treatment-resistant persister forms of to a more active form, potentially more recognizable by the host immune system. For , low doses of NEBB significantly reduced biofilm mass and metabolic activity while higher doses of NEBB increased biofilm mass and metabolic activity. The results suggest that targeted nutraceutical support may help disrupt biofilm communities, offering new facets for integrative combinational treatment strategies.
Topics: Humans; Anti-Bacterial Agents; Staphylococcus aureus; Anti-Infective Agents; Staphylococcal Infections; Biofilms; Pseudomonas aeruginosa; Microbial Sensitivity Tests
PubMed: 37072676
DOI: 10.4014/jmb.2212.12010 -
Research in Veterinary Science May 2023Single-layer centrifugation (SLC) with a low-density colloid is an efficient method for removing contaminating microorganisms from boar semen while recovering most...
Single-layer centrifugation (SLC) with a low-density colloid is an efficient method for removing contaminating microorganisms from boar semen while recovering most spermatozoa from the original sample. This study tested the performance of this technique, using 50-ml tubes, by spiking commercial semen doses prepared without antibiotics with selected bacterial species followed by storage at 17 °C. The doses were spiked up to 10/ml CFU (colony forming units) of the bacteria Burkholderia ambifaria, Pseudomonas aeruginosa, and Staphylococcus simulans. The semen was processed by SLC (15 ml of sample and 15 ml of colloid) with the colloid Porcicoll at 20% (P20) and 30% (P30), with a spiked control (CTL) and an unspiked control (CTL0), analyzing microbiology and sperm quality on days 0, 3 and 7. SLC completely removed B. ambifaria and S. simulans, considerably reducing P. aeruginosa and overall contamination (especially P30, ∼10 CFU/ml of total contamination on day 7, median). Sperm viability was lower in P20 and P30 samples at day 0, with higher cytoplasmic ROS. Still, results were similar in all groups on day 3 and reversed on day 7, indicating a protective effect of SLC (possibly directly by removal of damaged sperm and indirectly because of lower bacterial contamination). Sperm chromatin was affected by the treatment (lower DNA fragmentation and chromatin decondensation) and storage (higher overall condensation on day 7 as per chromomycin A3 and monobromobimane staining). In conclusion, SLC with low-density colloids can remove most bacteria in a controlled contamination design while potentially improving sperm quality and long-term storage at practical temperatures.
Topics: Male; Animals; Swine; Semen; Spermatozoa; Semen Analysis; Semen Preservation; Centrifugation; Colloids; Chromatin; Burkholderia; Sperm Motility
PubMed: 37031470
DOI: 10.1016/j.rvsc.2023.03.024