The greatest threat and medicinal impact within gram-positive pathogens are posed by two bacterial genera, Staphylococcus and Enterococcus. Chalcones have a wide range of biological activities and are recognized as effective templates in medicinal chemistry. This study provides comprehensive insight into the anti-staphylococcal and anti-enterococcal activities of two recently published brominated and chlorinated pyrazine-based chalcones, CH-0y and CH-0w. Their effects against 4 reference and 12 staphylococcal and enterococcal clinical isolates were evaluated. Bactericidal action, the activity in combination with selected conventional antibiotics, the study of post-antimicrobial effect (PAE, PAE/SME), and in vitro and in vivo toxicity, were included. In CH-0y, anti-staphylococcal activity ranging from MIC = 15.625 to 62.5 μM, and activity against E. faecium from 31.25 to 62.5 μM was determined. In CH-0w, anti-staphylococcal activity ranging from 31.25 to 125 μM, and activity against E. faecium and E. faecalis (62.5 μM) was revealed. Both CH-0y and CH-0w showed bactericidal action, beneficial impact on bacterial growth delay within PAE and PAE/SME studies, and non/low toxicity in vivo. Compared to CH-0w, CH-0y seems to have higher anti-staphylococcal and less toxic potential. In conclusion, chalcones CH-0y and CH-0w could be considered as structural pattern for future adjuvants to selected antibiotic drugs.
- Publication type
- Journal Article MeSH
Grampozitívne baktérie Enterococcus faecalis a E. faecium sú komensálne organizmy, ktoré sa pod vplyvom selekčného tlaku menia na pôvodcov infekčných ochorení. Z dôvodu prirodzenej rezistencie a efektívnych mechanizmov prenosu genetického materiálu je terapia enterokokových ochorení náročná. V antiinfekčnej terapii majú významné postavenie aminoglykozidy. Baktericídny účinok, vhodné farmakokinetické vlastnosti a synergické pôsobenie s beta-laktámami a glykopeptidmi podporujú ich používanie v terapeutickej praxi. K hlavným mechanizmom rezistencie voči aminoglykozidom patrí enzymatická inaktivácia antibiotika aminoglykozid=modifikujúcimi enzýmami (AGMEs), ktoré sa líšia schopnosťou inaktivovať rozdielne spektrum aminoglykozidov. K patogenite enterokokov prispievajú nemalou mierou aj faktory virulencie, ktorých participácia v patogenéze infekčných ochorení je zatiaľ nedostatočne objasnená. Vlastnosti enterokokov ako produkcia beta-hemolyzínu (Hly), želatinázy (Gel), agregačnej substancie (AS) a syntéza enterokokového povrchového proteínu (Esp) patria medzi najčastejšie študované potenciálne faktory virulencie.
Enterococcus faecalis and E. faecium are grampositive commensal bacteria that may become pathogenic under the selection pressure. In view of natural resistance and effective mechanisms of genetic transfer, the treatment of enterococcal diseases is rather complicated. Aminoglycosides are clinically relevant antimicrobials that are frequently prescribed in practice since having good pharmacokinetics and showing synergism with beta-lactam and glycopeptides. One of the major mechanisms involved in aminoglycoside resistance is inactivation of the antibiotic agent by aminoglycoside-modifying enzymes (AGMEs) differing in the capacity for inactivation of specific types of aminoglycosides. The factors of virulence are also involved in enterococcal pathogenicity but their role in the pathogenesis of infectious diseases remains unclear. Production of betahemolysin (Hly), gelatinase (Gel), and aggregation substance (AS), and synthesis of enterococcal surface protein (Esp) are among the most frequently studied potential virulence factors.
Cíl: Cílem práce je charakterizovat infekce vyvolané enterokoky ve Fakultní nemocnici Olomouc (FNOL) a definovat možnosti antibiotické léčby. Materiál a metody: Data byla získána z laboratorního informačního systému ENVIS LIMS. Za období 1. 1. 2015 až 31. 12. 2019 byly retrospektivně hodnoceny klinicky významné enterokoky ve FNOL a jejich rezistence k antibiotikům. K identifikaci byla do poloviny roku 2016 použita kritéria Facklama a Collinse a stanovení biochemických vlastností za použití En-coccus testu, následně byly všechny enterokoky určeny za pomoci systému MALDI-TOF MS. Citlivost k antibiotikům byla stanovena standardní diluční mikrometodou podle kritérií EUCAST. Výsledky: Ve sledovaném období 5 let bylo izolováno celkem 8 239 klinicky významných enterokoků. Nejčastěji izolovanými druhy byly Enterococcus faecalis a Enterococcus faecium, které v období 2017–2019 tvořily více než 90 %. Enterokoky byly nejčastěji izolovány z moče (35 %), dále z chirurgických ran (17 %) a stěrů z uretry/pochvy (17 %). Klinicky významné enterokoky byly v největší míře izolovány od pacientů s onkologickou diagnózou (22 %), dále od pacientů s nemocemi močové a pohlavní soustavy (15 %) a nemocemi dýchací soustavy (9 %). U kmenů Enterococcus faecalis byla zaznamenána velmi nízká rezistence k testovaným antibiotikům. V případě Enterococcus faecium byl prokázán 24% podíl vankomycin-rezistentních kmenů (VRE). Závěr: K primárním antibiotikům vhodným k léčbě infekcí s etiologickou rolí Enterococcus faecalis patří aminopeniciliny, v případě závažných infekcí v kombinaci s aminoglykosidy, především gentamicinem. U kmenů Enterococcus faecium je nutné volit glykopeptidy. Problém nastává u VRE, kde je k léčbě indikován linezolid či tigecyklin.
Aim: The study aimed to characterize enterococcal infections at the University Hospital Olomouc and to define antibiotic treatment options. Material and methods: The data was obtained from the ENVIS LIMS laboratory information system. Between 1 January 2015 and 31 December 2019, clinically relevant enterococci in the hospital and their resistance to antibiotics were retrospectively evaluated. Until mid-2016, criteria defined by Facklam and Collins and biochemical properties determined with the En-coccus test were used for identification. Subsequently, all enterococci were identified using the MALDI-TOF MS system. The susceptibility to antibiotics was determined using a standard microdilution method according to the EUCAST criteria. Results: A total of 8 239 clinically relevant enterococci were isolated over the 5-year period. The most frequently isolated species were Enterococcus faecalis and Enterococcus faecium, which accounted for more than 90% in the period 2017–2019. Enterococci were most frequently isolated from urine (35 %), surgical wounds (17 %) and urethral/vaginal swabs (17 %). Clinically relevant enterococci were most commonly isolated from patients with oncological diagnoses (22%), those with urinary and genital diseases (15%) and respiratory diseases (9 %). Enterococcus faecalis strains showed very low resistance to the antibiotics tested. Enterococcus faecium was shown to have 24 % proportion of vancomycin-resistant strains (VRE). Conclusion: Primary antibiotics suitable for treating infections with the etiological role of Enterococcus faecalis include aminopenicillins, in case of severe infections in combination with aminoglycosides, in particular gentamicin. For Enterococcus faecium strains, glycopeptides must be chosen. To treat VRE, linezolid or tigecycline are indicated.
Three hundred and ten enterococcal isolates (178 Enterococcus faecium, 68 E. durans, 49 E. faecalis, 8 E. italicus, 3 E. gallinarum, 3 E. casseliflavus, and 1 E. hirae) from Slovak Bryndza cheese were evaluated for susceptibility to nine antimicrobial agents (vancomycin, teicoplanin, ampicillin, streptomycin, gentamicin, erythromycin, rifampicin, nitrofurantoin, and ciprofloxacin). All enterococcal isolates from Bryndza cheese were susceptible to ampicillin, streptomycin, gentamicin, vancomycin, and teicoplanin as determined by the disk diffusion method. Vancomycin resistance genes vanA and vanB were not detected. Resistance rates of enterococcal isolates to rifampicin, erythromycin, ciprofloxacin, and nitrofurantoin were 24, 26, 2, and 1 %, respectively. Thirty-six % of E. faecium isolates and 22 % of the E. faecalis isolates were resistant to erythromycin. Resistance to rifampicin was similar in E. faecium (31 %) and E. faecalis (29 %). Both E. faecium and E. faecalis strains showed the same resistance to ciprofloxacin (2 %). E. durans isolates showed low levels of resistance to rifampicin, erythromycin, ciprofloxacin, and nitrofurantoin (1-4 %). Forty-eight (30 %) of the E. faecium isolates, two (3 %) of the E. durans isolates, and six (12 %) of the E. faecalis isolates exhibited multidrug resistance. The highest frequency of resistant enterococci was observed in Bryndza produced in winter season.
- MeSH
- Anti-Bacterial Agents pharmacokinetics immunology MeSH
- Drug Resistance, Microbial genetics immunology MeSH
- Enterococcus pathogenicity drug effects MeSH
- Research Support as Topic MeSH
- Dairy Products microbiology MeSH
- Drug Resistance, Multiple genetics immunology MeSH
- Sheep microbiology MeSH
- Cheese microbiology toxicity MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Geographicals
- Slovakia MeSH
Eight Gram-positive, catalase-negative bacterial strains were isolated during screening of enterococcal populations on plants. rep-PCR fingerprinting using the (GTG)(5) primer showed that the isolates constituted a single cluster that was separate from all known enterococcal species. 16S rRNA gene sequence phylogenetic analysis of three representative strains showed that the isolates belonged to the genus Enterococcus and that they clustered with the Enterococcus faecalis species group. Sequencing of the genes for the phenylalanyl-tRNA synthase alpha subunit (pheS) and the RNA polymerase alpha subunit (rpoA) also revealed the isolates' separate taxonomic position. Application of whole-cell protein fingerprinting, automated ribotyping and extensive phenotyping demonstrated the genetic and phenotypic homogeneity of the isolates and confirmed their separate position within the E. faecalis species group. The isolates represent a novel species of the genus Enterococcus, for which the name Enterococcus plantarum sp. nov. is proposed; the type strain is CCM 7889(T) (=LMG 26214(T)=C27(T)).
- MeSH
- DNA, Bacterial chemistry genetics MeSH
- DNA-Directed RNA Polymerases genetics MeSH
- Enterococcus classification genetics isolation & purification physiology MeSH
- Phenylalanine-tRNA Ligase genetics MeSH
- Phylogeny MeSH
- Catalase metabolism MeSH
- Molecular Sequence Data MeSH
- Molecular Typing MeSH
- DNA, Ribosomal chemistry genetics MeSH
- RNA, Ribosomal, 16S genetics MeSH
- Plants microbiology MeSH
- Sequence Analysis, DNA MeSH
- Cluster Analysis MeSH
- Bacterial Typing Techniques MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
The aim of the study was to explore production of seven biogenic amines (phenylethylamine, histamine, cadaverine, tyramine, putrescine, spermine and/or spermidine) by selected staphylococci and enterococci. Thirty three enterococcal strains isolated from rabbit meat (Oryctolagus cuniculus f. domesticus) and 21 staphylococcal strains isolated from intestinal content of trout (Salmo trutta morpha fario) were tested. Production of biogenic amines was evaluated after cultivation of the tested microorganisms in the de Man, Rogosa and Sharpe Broth (enterococci) or in the Brain Heart Infusion Broth (staphylococci). Both the above cultivation media were enriched with selected amino acids (histidine, tyrosine, arginine, ornithine and lysine; 2g/L each) serving as precursors of biogenic amines. After cultivation, levels of the monitored biogenic amines in broths were analysed by a high performance liquid chromatography equipped with a UV/VIS DAD detector. Among 21 staphylococci, 18 strains produced tyramine or cadaverine, 13 strains formed putrescine or phenylethylamine and only one strain generated histamine. Two staphylococcal strains produced cadaverine levels above 1000 mg/L. Among 33 enterococcal strains, 27 formed cadaverine, 18 strains produced tyramine, 10 strains generated phenylethylamine, and 2 strains gave putrescine. Most of the tyramine producing enterococci generated more than 1000 mg/L of this biogenic amine. Production of spermine or spermidine by the studied strains was not proved.
- MeSH
- Biogenic Amines analysis biosynthesis MeSH
- Decarboxylation MeSH
- Enterococcus classification growth & development isolation & purification metabolism MeSH
- Rabbits * MeSH
- Meat microbiology MeSH
- Trout * MeSH
- Staphylococcus classification growth & development isolation & purification metabolism MeSH
- Intestines microbiology MeSH
- Animals MeSH
- Check Tag
- Rabbits * MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
A group of nine presumptive enterococci was isolated on enterococcal selective media Slanetz-Bartley agar and/or kanamycin-esculin-azide agar during a screening of Enterococcus spp. in surface waters. All strains formed a homogeneous cluster separated from all enterococcal species using rep-PCR fingerprinting with the (GTG)(5) primer but they matched fingerprints revealed by Lactococcus lactis subsp. lactis representatives. Further identification using extensive biotyping and automated ribotyping with EcoRI (RiboPrinter(R) microbial characterization system) confirmed all strains as L. lactis subsp. lactis in full correspondence with the (GTG)(5)-PCR. We demonstrated that L. lactis subsp. lactis strains occur in different surface waters and can be confused with enterococci due to their positive growth on selective enterococcal media as well as positive results in tests commonly used for identification of the genus Enterococcus (esculin hydrolysis, acetoin and pyrrolidonyl arylamidase production, growth at 10 degrees C and in 6.5% NaCl). The (GTG)(5)-PCR fingerprinting was revealed as a reliable and fast method for the identification of L. lactis subsp lactis while automated ribotyping with EcoRI proved to be a good tool for intrasubspecies typing purposes.
