Two heretofore uncharacterised abietane diterpenes, sincoetsin C (1) and 3-hydroxyspirocoleon 7-O-β-D-glucoside (4), were isolated from a methanolic extract of Coleus blumei Benth. (Lamiaceae), along with the known compounds, scutellarioidone A (2) and spirocoleon 7-O-β-D-glucoside (3) using chromatographic techniques. Their structures were determined by 1D and 2D nuclear magnetic resonance including HSQC, HMBC, COSY and NOESY experiments, mass spectrometry (HR-MS) and other spectroscopic methods (UV, IR). Their antibacterial activity against the reference strain of methicillin-resistant Staphylococcus aureus subsp. aureus CCM 4750 (MRSA) was evaluated using optical absorption to obtain quantitative information on their growth. All isolated compounds displayed anti-MRSA 4750 activity at the concentration of 512 μg/mL. Sincoetsin C (1) was the abietane diterpene most active against MRSA 4750, with a minimum inhibitory concentration of 128 μg/mL.
- MeSH
- Coleus * chemie MeSH
- diterpeny abietanové izolace a purifikace farmakologie MeSH
- diterpeny * izolace a purifikace farmakologie MeSH
- fytonutrienty izolace a purifikace farmakologie MeSH
- methicilin rezistentní Staphylococcus aureus * účinky léků MeSH
- Staphylococcus účinky léků MeSH
- Publikační typ
- časopisecké články MeSH
Background: Increasing resistance has resulted in an urgent need for new antimicrobial drugs. A systematic me-too approach was chosen to modify clinically used sulfonamides to obtain their imines. Methods & results: Twenty-five compounds were synthesized and evaluated for their antibacterial activity. The most active compounds were also investigated against methicillin- and trimethoprim/sulfamethoxazole (SMX)-resistant Gram-positive species. Staphylococci shared the highest susceptibility including resistant strains with minimum inhibitory concentrations from 3.91 μM (≥2.39 μg ml-1). Crucially, the compounds inhibit MRSA and trimethoprim/SMX-resistant Staphylococci without any cross-resistance. Modification of parent sulfonamides turned a bacteriostatic effect into a bactericidal effect. Toxicity for HepG2 and hemolytic properties were also determined. Conclusions: The presence of a dihalogenated salicylidene moiety is required for optimal activity. Based on toxicity, promising derivatives for further investigation were identified.
- MeSH
- aldehydy chemie farmakologie MeSH
- antibakteriální látky chemická syntéza chemie farmakologie MeSH
- bakteriální léková rezistence účinky léků MeSH
- iminy chemie farmakologie MeSH
- mikrobiální testy citlivosti MeSH
- molekulární struktura MeSH
- Staphylococcus účinky léků MeSH
- sulfonamidy chemie farmakologie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Introduction.Staphylococcus aureus (SA) and Staphylococcus epidermidis (SE) are the most common pathogens from the genus Staphylococcus causing biofilm-associated infections. Generally, biofilm-associated infections represent a clinical challenge. Bacteria in biofilms are difficult to eradicate due to their resistance and serve as a reservoir for recurring persistent infections.Gap Statement. A variety of protocols for in vitro drug activity testing against staphylococcal biofilms have been introduced. However, there are often fundamental differences. All these differences in methodical approaches can then be reflected in the form of discrepancies between results.Aim. In this study, we aimed to develop optimal conditions for staphylococcal biofilm formation on pegs. The impact of peg surface modification was also studied.Methodology. The impact of tryptic soy broth alone or supplemented with foetal bovine serum (FBS) or human plasma (HP), together with the impact of the inoculum density of bacterial suspensions and the shaking versus the static mode of cultivation, on total biofilm biomass production in SA and SE reference strains was studied. The surface of pegs was modified with FBS, HP, or poly-l-lysine (PLL). The impact on total biofilm biomass was evaluated using the crystal violet staining method and statistical data analysis.Results. Tryptic soy broth supplemented with HP together with the shaking mode led to crucial potentiation of biofilm formation on pegs in SA strains. The SE strain did not produce biofilm biomass under the same conditions on pegs. Preconditioning of peg surfaces with FBS and HP led to a statistically significant increase in biofilm biomass formation in the SE strain.Conclusion. Optimal cultivation conditions for robust staphylococcal biofilm formation in vitro might differ among different bacterial strains and methodical approaches. The shaking mode and supplementation of cultivation medium with HP was beneficial for biofilm formation on pegs for SA (ATCC 29213) and methicillin-resistant SA (ATCC 43300). Peg conditioning with HP and PLL had no impact on biofilm formation in either of these strains. Peg coating with FBS showed an adverse effect on the biofilm formation of these strains. By contrast, there was a statistically significant increase in biofilm biomass production on pegs coated with FBS and HP for SE (ATCC 35983).
- MeSH
- bakteriologické techniky přístrojové vybavení metody MeSH
- biofilmy klasifikace účinky léků růst a vývoj MeSH
- biomasa MeSH
- druhová specificita MeSH
- kultivační média chemie farmakologie MeSH
- lidé MeSH
- matrix extracelulárních polymerních látek klasifikace účinky léků MeSH
- Staphylococcus klasifikace účinky léků fyziologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Coagulase-negative staphylococci (CoNS) are an important cause of human and animal diseases. Treatment of these diseases is complicated by their common antimicrobial resistance, caused by overuse of antibiotics in hospital and veterinary environment. Therefore, they are assumed to serve as a reservoir of resistance genes often located on plasmids. In this study, we analyzed plasmid content in 62 strains belonging to 10 CoNS species of human and veterinary origin. In 48 (77%) strains analyzed, 107 different plasmids were detected, and only some of them showed similarities with plasmids found previously. In total, seven different antimicrobial-resistance genes carried by plasmids were identified. Five of the CoNS staphylococci carried plasmids identical with either those of other CoNS species tested, or a well characterized Staphylococcus aureus strain COL, suggesting plasmid dissemination through horizontal transfer. To demonstrate the possibility of horizontal transfer, we performed electroporation of four resistance plasmids among Staphylococcus epidermidis, Staphylococcus petrasii, and coagulase-positive S. aureus strains. Plasmids were transferred unchanged, were stably maintained in recipient strains, and expressed resistance genes. Our work demonstrates a great variability of plasmids in human and veterinary staphylococcal strains and their ability to maintain and express resistance plasmids from other staphylococcal species.
- MeSH
- antibakteriální látky farmakologie MeSH
- bakteriální léková rezistence genetika MeSH
- genetická variace * MeSH
- koagulasa MeSH
- lidé MeSH
- mikrobiální testy citlivosti MeSH
- plazmidy účinky léků genetika MeSH
- přenos genů horizontální MeSH
- stafylokokové infekce MeSH
- Staphylococcus aureus genetika MeSH
- Staphylococcus účinky léků enzymologie genetika MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Vancomycin is the first-choice antibiotic for infants with β-lactam-resistant gram-positive bacterial infection. Despite long experience of prescribing of this drug optimal dosing is still challenging. This study aimed at investigating variables predicting vancomycin clearance in order to propose optimal maintenance dosing in infants treated for suspected or culture-proven sepsis. METHODS: Vancomycin pharmacokinetics was calculated in a one-compartmental model based on serum concentrations. A linear regression model was used to explore relationships between vancomycin clearance and expected covariates. RESULTS: Twenty-two patients were enrolled into the study. Median (IQR) postnatal age was 157 (112-238) days. The median (IQR) volume of distribution and clearance for vancomycin were 0.50 (0.39-0.94) L/kg and 0.112 (0.095-0.133) L/h/kg, respectively. Vancomycin clearance was associated with actual body weight, height, body surface area, gestational age, postnatal age, postmenstrual age and estimate glomerular filtration rate. Actual body weight was the best predictive variable for vancomycin clearance. Daily maintenance dose (mg) calculated as 76.28 × actual body weight (kg) - 41.57 most closely approximated optimal dosing based on individual pharmacokinetics. This relationship was used to construct a dosing nomogram. CONCLUSIONS: We developed an easy-to-use dosing nomogram for maintaining a vancomycin average steady-state concentration of 22.5 mg/L based on actual body weight.
- MeSH
- antibakteriální látky aplikace a dávkování farmakokinetika MeSH
- kojenec MeSH
- lidé MeSH
- monitorování léčiv * MeSH
- nomogramy * MeSH
- regresní analýza MeSH
- sepse farmakoterapie mikrobiologie MeSH
- Staphylococcus účinky léků MeSH
- tělesná hmotnost * MeSH
- vankomycin aplikace a dávkování farmakokinetika MeSH
- Check Tag
- kojenec MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- pozorovací studie MeSH
An agar well diffusion assay (AWDA) was used to isolate a high bacteriocin-producing strain with a broad spectrum of antibacterial activity, strain MXG-68, from Inner Mongolia traditional fermented koumiss. Lactobacillus plantarum MXG-68 was identified by morphological, biochemical, and physiological characteristics and 16S rDNA analysis. The production of antibacterial substance followed a growth-interrelated model, starting at the late lag phase of 4 h and arriving at a maximum value in the middle of the stationary phase at 24 h. Antibacterial activity was abolished or decreased in the presence of pepsin, chymotrypsin, trypsin, proteinase, and papain K. The results showed that antibacterial substances produced by L. plantarum MXG-68 were proteinaceous and could thus be classified as the bacteriocin, named plantaricin MXG-68. The molar mass of plantaricin MXG-68 was estimated to be 6.5 kDa, and the amino acid sequence of its N-terminal was determined to be VYGPAGIFNT. The mode of plantaricin MXG-68 action was determined to be bactericidal. Bacteriocin in cell-free supernatant (CFS) at pH 7 was stable at different temperatures (60 °C, 80 °C, 100 °C, 121 °C for 30 min; 4 °C and - 20 °C for 30 days), as well as at pH 2.0-10.0. Antibacterial activity maintained stable after treatment with organic solvents, surfactants, and detergents but increased in response to EDTA. Response surface methodology (RSM) revealed the optimum conditions of bacteriocin production in L. plantarum MXG-68, and the bacteriocin production in medium optimized by RSM was 26.10% higher than that in the basal MRS medium.
- MeSH
- antibakteriální látky biosyntéza chemie farmakologie MeSH
- bakteriociny biosyntéza chemie farmakologie MeSH
- fylogeneze MeSH
- kinetika MeSH
- kultivační média MeSH
- kumys mikrobiologie MeSH
- Lactobacillus plantarum chemie klasifikace fyziologie MeSH
- molekulová hmotnost MeSH
- potravinářská mikrobiologie MeSH
- RNA ribozomální 16S genetika MeSH
- sekvence aminokyselin MeSH
- stabilita proteinů MeSH
- Staphylococcus účinky léků MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Čína MeSH
OBJECTIVE: Drug-resistant staphylococci have been a growing threat to the community and hospitals due to the misuse of antibiotics by humans, industrialisation and lack of novel antimicrobials currently available. Little is known about the prevalence of drug-resistant staphylococci in non-healthcare environments outside hospitals in the London area. Staphylococci can spread via contact with contaminated objects. Traffic light buttons present a fast and easy transmission route for staphylococci. METHODS: Traffic light buttons outside a major hospital in London were swabbed and cultured onto selective media to isolate staphylococci bacteria before performing antimicrobial susceptibility testing on the isolates. The identity of the isolates were determined using MALDI-TOF mass spectrometry (MS). Staphylococci isolates resistant to oxacillin were further tested for minimum inhibitory concentration (MIC). PCR analysis of the mecA gene, a gene that confers resistance to oxacillin, is used to determine the level of resistance to oxacillin. RESULTS: Eight different staphylococcal species were identified by MALDI-TOF-MS analysis. Out of the 66 staphylococci isolates, 16 were resistant to multiple antibiotics including six isolates which were oxacillin resistant. CONCLUSION: This work provides evidence of the presence of multidrug-resistant staphylococci in the vicinity of the hospital environment in London.
- MeSH
- antibakteriální látky farmakologie MeSH
- lidé MeSH
- mikrobiální testy citlivosti MeSH
- mnohočetná léková rezistence * MeSH
- nemocnice MeSH
- oxacilin farmakologie MeSH
- Staphylococcus účinky léků izolace a purifikace MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Londýn MeSH
The intestinal microbiota has enormous impact on the health and performance of horses. Staphylococci belong in the phylum Firmicutes, and their occurrence, especially of methicillin-resistant strains and species, has been reported in horses previously. Moreover, biofilm formation is one of the virulence factors; it has been not completely studied in fecal coagulase-negative staphylococci (CoNS) from horses. Therefore, this study was focused on biofilm formation by various species of fecal CoNS from horses because it has been never reported before. In addition, their antibiotic profile was tested. Horses (42) of various breeds from Slovakia/Poland were sampled. Variability in the species of CoNS was detected in feces of horses. Thirty-two strains were identified by using the MALDI-TOF system and classified into nine species and three subspecies of CoNS: Staphylococcus capitis, S. cohnii subsp. cohnii, S. cohnii subsp. urealyticus, S. cohnii subsp. casei, S. epidermidis, S. haemolyticus, S. pasteuri, S. sciuri, S. vitulinus, S. warneri, and S. xylosus. The most frequent species was S. vitulinus. Twenty-two strains showed high biofilm production; 10 strains showed low-grade biofilm production. The highest biofilm formation was measured in the species S. xylosus. Eleven strains (of 32) were methicillin-resistant; the others were susceptible to methicillin.
- MeSH
- antibakteriální látky farmakologie MeSH
- biofilmy růst a vývoj MeSH
- druhová specificita MeSH
- feces mikrobiologie MeSH
- koagulasa nedostatek MeSH
- koně MeSH
- kyselina mléčná metabolismus MeSH
- mikrobiální testy citlivosti MeSH
- rezistence na methicilin MeSH
- stafylokokové infekce epidemiologie mikrobiologie veterinární MeSH
- Staphylococcus klasifikace účinky léků izolace a purifikace fyziologie MeSH
- střevní mikroflóra MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Polsko MeSH
- Slovenská republika MeSH
The aim of this study was to assess pit latrine samples from a peri-urban community in KwaZulu-Natal (South Africa) for the presence of multidrug-resistant (MDR) Staphylococcus spp. Standard procedures were used to isolate Staphylococcus spp. from pit latrine fecal sludge samples, with confirmation at genus level by polymerase chain reaction (PCR). Sixty-eight randomly selected pit latrine Staphylococcus spp. isolates were further characterized by using established disk diffusion procedures. An average Staphylococcus spp. count of 2.1 × 105 CFU per g fecal material was established using two randomly selected pit latrine samples. Of the 68-selected Staphylococcus spp. pit latrine isolates, 49% were identified as coagulase positive, 51% as coagulase negative and 65% (12 coagulase positive, 32 coagulase negative isolates) were categorized as MDR. The majority (66/68) of Staphylococcus spp. isolates displayed resistance to fusidic acid while only 5/68 isolates displayed resistance to chloramphenicol. The pit latrine samples analyzed in this study are a source of MDR Staphylococcus spp., highlighting the need for proper hygiene and sanitation regimes in rural communities using these facilities.
- MeSH
- antibakteriální látky farmakologie MeSH
- bakteriální geny genetika MeSH
- bakteriální proteiny metabolismus MeSH
- DNA bakterií genetika MeSH
- feces mikrobiologie MeSH
- koagulasa metabolismus MeSH
- mikrobiální testy citlivosti MeSH
- mikrobiální viabilita účinky léků MeSH
- mnohočetná bakteriální léková rezistence * MeSH
- odpadní vody mikrobiologie MeSH
- Staphylococcus účinky léků enzymologie genetika izolace a purifikace MeSH
- toalety * MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
- Geografické názvy
- Jihoafrická republika MeSH
- MeSH
- bakteriální proteiny genetika MeSH
- glykopeptidy farmakologie MeSH
- jednonukleotidový polymorfismus MeSH
- lidé MeSH
- membránové proteiny genetika MeSH
- mikrobiální testy citlivosti MeSH
- mutace MeSH
- stafylokokové infekce mikrobiologie MeSH
- Staphylococcus účinky léků genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- dopisy MeSH
- práce podpořená grantem MeSH
