The Photorhabdus species is a Gram-negative bacteria of the family Morganellaceae that is known for its mutualistic relationship with Heterorhabditis nematodes and pathogenicity toward insects. This study is focused on the characterization of the recombinant lectin PLL3 with an origin in P. laumondii subsp. laumondii. PLL3 belongs to the PLL family of lectins with a seven-bladed β-propeller fold. The binding properties of PLL3 were tested by hemagglutination assay, glycan array, isothermal titration calorimetry, and surface plasmon resonance, and its structure was determined by X-ray crystallography. Obtained data revealed that PLL3 binds similar carbohydrates to those that the other PLL family members bind, with some differences in the binding properties. PLL3 exhibited the highest affinity toward l-fucose and its derivatives but was also able to interact with O-methylated glycans and other ligands. Unlike the other members of this family, PLL3 was discovered to be a monomer, which might correspond to a weaker avidity effect compared to homologous lectins. Based on the similarity to the related lectins and their proposed biological function, PLL3 might accompany them during the interaction of P. laumondii with both the nematode partner and the insect host.
- MeSH
- bakteriální proteiny chemie genetika metabolismus MeSH
- fruktosa metabolismus MeSH
- kalorimetrie MeSH
- krystalografie rentgenová MeSH
- lektiny chemie genetika metabolismus MeSH
- Photorhabdus metabolismus MeSH
- povrchová plasmonová rezonance MeSH
- rekombinantní proteiny chemie metabolismus MeSH
- sekundární struktura proteinů MeSH
- vazebná místa MeSH
- Publikační typ
- časopisecké články MeSH
A recently described bangle lectin (PHL) from the bacterium Photorhabdus asymbiotica was identified as a mainly fucose-binding protein that could play an important role in the host-pathogen interaction and in the modulation of host immune response. Structural studies showed that PHL is a homo-dimer that contains up to seven L-fucose-specific binding sites per monomer. For these reasons, potential ligands of the PHL lectin: α-L-fucopyranosyl-containing mono-, di-, tetra-, hexa- and dodecavalent ligands were tested. Two types of polyvalent structures were investigated - calix[4]arenes and dendrimers. The shared feature of all these structures was a C-glycosidic bond instead of the more common but physiologically unstable O-glycosidic bond. The inhibition potential of the tested structures was assessed using different techniques - hemagglutination, surface plasmon resonance, isothermal titration calorimetry, and cell cross-linking. All the ligands proved to be better than free L-fucose. The most active hexavalent dendrimer exhibited affinity three orders of magnitude higher than that of standard L-fucose. To determine the binding mode of some ligands, crystal complex PHL/fucosides 2 - 4 were prepared and studied using X-ray crystallography. The electron density in complexes proved the presence of the compounds in 6 out of 7 fucose-binding sites.
- MeSH
- antibakteriální látky chemie farmakologie terapeutické užití MeSH
- bakteriální infekce farmakoterapie mikrobiologie MeSH
- bakteriální proteiny antagonisté a inhibitory chemie izolace a purifikace metabolismus MeSH
- dendrimery chemie farmakologie terapeutické užití MeSH
- erytrocyty MeSH
- fukosa analogy a deriváty farmakologie terapeutické užití MeSH
- hemaglutinace účinky léků MeSH
- interakce hostitele a patogenu účinky léků MeSH
- krystalografie rentgenová MeSH
- lektiny antagonisté a inhibitory chemie izolace a purifikace metabolismus MeSH
- lidé MeSH
- ligandy MeSH
- molekulární modely MeSH
- Photorhabdus metabolismus MeSH
- povrchová plasmonová rezonance MeSH
- rekombinantní proteiny chemie izolace a purifikace metabolismus MeSH
- vazebná místa MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
As a part of ongoing activities towards the design of ligands against pathogenic lectins, a synthesis of original α-C-galacto/α-C-manno/α-C-fucopyranosyl glycomimetics based on a calix[4]arene scaffold and their binding evaluation is described. The interactions of the glycomimetics with seven lectins of various origins were carried out using agglutination inhibition assays. The 1,3-alternate tetra-C-fucosylated ligand and its derivative having a tertBu group at the upper rim of the calix[4]arene scaffold were the most potent towards the AAL lectin family (RSL, AFL, AAL, AOL) and BC2L-C. As AFL and RSL originate from important human (Aspergillus fumigatus) and plant (Ralstonia solanacearum) pathogens, the inhibition potency of both leading structures was assessed by surface plasmon resonance. With AFL, both structures exhibited an approximately three orders of magnitude increase in affinity compared to the reference l-fucose. The role of tertBu groups as "aglycon-assisted" events was illustrated by NMR. Furthermore, both compounds showed significantly increased ability to inhibit BC2L-C (from human pathogen Burkholderia cenocepacia) cell agglutination and were able to cross-link whole B. cenocepacia cells. Although the ligands failed to significantly inhibit the agglutination activity of LecA and LecB from Pseudomonas aeruginosa, tetra-C-galactosylated calix[4]arene with tertBu groups at the upper rim of the 1,3-alternate conformation inhibited P. aeruginosa biofilm formation efficiently. This systematic and comprehensive study highlights the fact that hydrolytically stable polyvalent C-glycomimetics should be regarded as potent and selective ligands capable of acting as antiadhesive agents.
- MeSH
- aglutinace účinky léků MeSH
- biofilmy účinky léků MeSH
- biomimetické materiály chemie farmakologie MeSH
- kalixareny chemie farmakologie MeSH
- lektiny chemie MeSH
- lidé MeSH
- ligandy MeSH
- molekulární konformace MeSH
- molekulární modely MeSH
- Pseudomonas aeruginosa účinky léků fyziologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
The C-type lectin DC-SIGN expressed on immature dendritic cells is a promising target for antiviral drug development. Previously, we have demonstrated that mono- and divalent C-glycosides based on d-manno and l-fuco configurations are promising DC-SIGN ligands. Here, we described the convergent synthesis of C-glycoside dendrimers decorated with 4, 6, 9, and 12 α-l-fucopyranosyl units and with 9 and 12 α-d-mannopyranosyl units. Their affinity against DC-SIGN was assessed by surface plasmon resonance (SPR) assays. For comparison, parent O-glycosidic dendrimers were synthesized and tested, as well. A clear increase of both affinity and multivalency effect was observed for C-glycomimetics of both types (mannose and fucose). However, when dodecavalent C-glycosidic dendrimers were compared, there was no difference in affinity regarding the sugar unit (l-fuco, IC50 17 μM; d-manno, IC50 12 μM). For the rest of glycodendrimers with l-fucose or d-mannose attached by the O- or C-glycosidic linkage, C-glycosidic dendrimers were significantly more active. These results show that in addition to the expected physiological stability, the biological activity of C-glycoside mimetics is higher in comparison to the corresponding O-glycosides and therefore these glycomimetic multivalent systems represent potentially promising candidates for targeting DC-SIGN.
- MeSH
- biomimetické materiály chemie farmakologie MeSH
- fukosa chemie MeSH
- inhibiční koncentrace 50 MeSH
- lektiny typu C antagonisté a inhibitory MeSH
- mannosa chemie MeSH
- molekuly buněčné adheze antagonisté a inhibitory MeSH
- receptory buněčného povrchu antagonisté a inhibitory MeSH
- Publikační typ
- časopisecké články MeSH
Východisko: Myofasciálny bolestivý syndróm šije patrí k najčastejším myoskeletálnym ochoreniam. Cieľ: Zhodnotenie efektivity piatich terapeutických postupov pri liečbe myofasciálného syndrómu šijovej oblasti. Súbor a metodika: Do výskumu bolo zaradených 50 pacientov s bolesťou šije minimálne po dobu 6 týždňov. Vylučovacie kritéria boli závažné diskopátie so zánikovou alebo iritačnou symptomatológiou, zápalové, onkologické ochorenia, myelopatie, instability a ochorenia centrálneho motoneurónu. Elektrická aktivita horných vlákien m. trapezius bola snímaná bilaterálne povrchovou elektromyografiou v troch rôznych polohách po dobu 20 sekúnd pred a po terapeutickom zásahu. Porovnanie nálezov u každého pacienta pred a po intervencii sme vyhodnotili pomocou párového t – testu s hladinou významnosti p<0,05. Následne sme Fisherovým presným vzorcom stanovili percentuálne zastúpenie signifikantých nálezov v každej terapeutickej skupine. Pre každú vyšetrovaciu polohu sme určili ako kritérium úspechu zásahu, ak minimálne 70 % pacientov dosiahne signifikantné zníženie elektrickej aktivity. Určením aritmetického priemeru v jednej terapeutickej skupine sme stanovili priemernú hodnotu efektu terapie bez ohľadu na vyšetrovaciu pozíciu. Výsledky: Pri hodnotení v rôznych vyšetrovacích polohách ako aj pri stanovení priemernej hodnoty pre každú metodiku dosiahla najlepšie výsledky metóda PIR (3x bola zastúpená v hodnotení úspešnosti podľa lokalizácie, priemerná hodnota bola 60 % signifikantne zlepšených pacientov, p<0,05). Hranicu 70 % podľa lokalizácie prekonala metóda DNS a teploliečba, a naopak, ani v jednom prípade nedosiahli manuálne techniky a AGR. Po spriemerovaní hodnôt dosiahla úspešnosť inervencie teploliečbou 59 %, metodika DNS 55 %, manuálne techniky 52 % a AGR 39 %. Záver: Práca dokazuje, že aj 10-minútový terapeutický zákrok dokáže signifikantne u (39 % - 60 %) pacientov, podľa zvolenej metodiky pozitívne ovplyvniť elektrickú aktivitu trapézového svalu. Dáva nám to jednoznačné potvrdenie významu používania autoterapeutických praktík v bežnom živote pacientov, a predovšetkým ich zaradenie aj priamo do pracovného prostredia. Najvýraznejší efekt bol dosiahnutý metódou PIR.
Background: Myofascial pain syndrome belongs to most frequent musculoskeletal disorders Objective: Evaluating the effectiveness of five therapeutic procedures in the treatment of myofascial syndrome of the nucha region syndrome. Cohort and methods: fifty patients suffering from the nucha pains for at least six weeks were enrolled in the study. The exclude g criteria included severe discopathies with extinction or irritation symptomatology, inflammation and oncological diseases, myelopathies, instability and diseases of the central motoneuron. Electric activity of upper fiber of the trapezoid muscle was monitored by bilateral surface electromyography in three different positions for the period of 20 seconds and after therapeutic intervention. The comparison of findings before and after the intervention in each patient was evaluated by paired t-test at the p<0.05 level of significance. Subsequently, the percent representation of significant results was assessed in every therapeutic group. The criterion of successful intervention was set for every examination position, if at least 70% of patients reached a significant decrease of electric activity. The calculation of arithmetic mean in one therapeutic group established the mean value of the treatment effect irrespective of the examination position. Results: In evaluating the various examination positions, as well as in determining the mean value for every method, the best results were provided by the PIR method (represented three times in the evaluation of success according to localization, the mean value being 60% of significantly improved patients, p<0.05). The limit of 70% according to localization was surpassed by the DNS method and thermal therapy, whereas manual techniques and AGR did not reach the value in any case. In averaging the values, the intervention success of thermal therapy reached 59%, manual techniques 52% and AGR reached 39%. Conclusion: The results made it clear that even a 10-minute therapeutic intervention can significantly influence electric activity of the trapezoid muscle in 39 % to 60 % in relation to the selected method. It confirmed unequivocally the significance of autotherapy practices in a common life of patients and, particularly, their inclusion into the working environment. The PIR method proved to reach the most considerable progress.
- MeSH
- dospělí MeSH
- elektromyografie MeSH
- indukovaná hypertermie MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- povrchové zádové svaly patofyziologie MeSH
- senioři MeSH
- syndromy myofasciální bolesti diagnóza patofyziologie rehabilitace MeSH
- terapie cvičením MeSH
- výsledek terapie MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
The discovery of effective ligands for DC-SIGN receptor is one of the most challenging concepts of antiviral drug design due to the importance of this C-type lectin in infection processes. DC-SIGN recognizes mannosylated and fucosylated oligosaccharides but glycosidic linkages are accessible to both chemical and enzymatic degradations. To avoid this problem, the synthesis of stable glycoside mimetics has attracted increasing attention. In this work we establish for the first time mono- and divalent C-glycosides based on d-manno and l-fuco configurations as prospective DC-SIGN ligands. In particular, the l-fucose glycomimetics were more active than the respective d-mannose ones. The highest affinity was assessed for simple 1,4-bis(α-l-fucopyranosyl)butane (SPR: IC50 0.43 mM) that displayed about twice higher activity than natural ligand Le(x). Our results make C-glycosides attractive candidates for multivalent presentations.
- MeSH
- biomimetika MeSH
- fukosa chemie MeSH
- glykosidy chemická syntéza chemie MeSH
- lektiny typu C chemie metabolismus MeSH
- lidé MeSH
- mannosa chemie MeSH
- molekulární struktura MeSH
- molekuly buněčné adheze chemie metabolismus MeSH
- receptory buněčného povrchu chemie metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
