499 research outputs found
A Novel Approach in Skin Care: By-Product Extracts as Natural UV Filters and an Alternative to Synthetic Ones
Cell type-specific regulation of CFTR trafficking—on the verge of progress
Trafficking of the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) protein is a complex process that starts with its biosynthesis and folding in the endoplasmic reticulum. Exit from the endoplasmic reticulum (ER) is coupled with the acquisition of a compact structure that can be processed and traffic through the secretory pathway. Once reaching its final destination—the plasma membrane, CFTR stability is regulated through interaction with multiple protein partners that are involved in its post-translation modification, connecting the channel to several signaling pathways. The complexity of the process is further boosted when analyzed in the context of the airway epithelium. Recent advances have characterized in detail the different cell types that compose the surface epithelium and shifted the paradigm on which cells express CFTR and on their individual and combined contribution to the total expression (and function) of this chloride/bicarbonate channel. Here we review CFTR trafficking and its relationship with the knowledge on the different cell types of the airway epithelia. We explore the crosstalk between these two areas and discuss what is still to be clarified and how this can be used to develop more targeted therapies for CF
Synbiobacther: engineering “therapeutic” bacteria
SYNBIOBACTHER – Engineering “therapeutic” bacteria
Rodrigues LR, Rodrigues JL, Machado CD, Kluskens L, Mota M, Rocha I, Ferreira EC
IBB-Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal
Statistics show that over 1.3 million persons will be diagnosed with breast cancer worldwide this year, hence this is an enormously important health risk, and progress leading to enhanced survival is a global priority. Several strategies have been pursued over the years, whether searching new biomarkers, drugs or treatments. Ultrasound is often used to treat solid tumours. However, this technique is not always successful, as sometimes it just heats the tumour without destroying it. If it would be possible to link this treatment with the expression/release of a therapeutic agent, the joint effect could be more effective. Some efforts have been made in this direction, although to date the results have not been very encouraging; potential reasons include lack of precise control over administration of the drug. Therefore, the idea is to overcome this barrier through the use of synthetic and systems biology strategies to engineer a model bacterium to trigger release of a therapeutic agent concurrent with ultrasound treatment. The search for new cancer-fighting drugs has traditionally driven research efforts in this field. Curcumin, due to its attractive properties as a novel drug has recently attracted increased attention. Nevertheless, it is well known that it has a poor bioavailability. Cellular uptake is slow, and it is quickly metabolised once inside cells, requiring repetitive oral doses to achieve sufficient concentration inside the cells for therapeutic activity. Hence, the possibility of synthesizing curcumin in situ in a controlled way, as proposed in this project, provides a powerful alternative.
References
[1] Katsuyama Y, Matsuzawa M, Funa N, Horinouchi S, “Production of curcuminoids by Escherichia coli carrying an artificial biosynthesis pathway”, Microbiology (2008) 154:2620-2628.
[2] Forbes NS, “Engineering the perfect (bacterial) cancer therapy”, Nat, Rev. Cancer (2010) 10:785-794
(4aS,4bR,7R,10aS)-3,7-Dimethyl-10a-(propan-2-yl)-1,4,4a,4b,5,6,7,8,10,10a-decahydrophenanthrene-1,4-dione
In the title compound, C19H26O2, the A ring adopts a chair conformation, whereas the B and C rings both adopt distorted half-chair conformations with the quaternary C atom common to both rings lying 0.577 (3) and 0.648 (3) Å out of the approximate plane defined by the remaining five C atoms (r.m.s. deviations = 0.1386 and 0.1156 Å) for the B and C rings, respectively. Molecules are assembled in the crystal through C—H⋯O interactions involving both carbonyl O atoms, which lead to supramolecular chains aligned along the b axis
Aptasensor for the detection of Moraxella catarrhalis adhesin UspA2
Innovative point-of-care (PoC) diagnostic platforms are desirable to surpass the deficiencies of conventional laboratory diagnostic methods for bacterial infections and to tackle the growing antimicrobial resistance crisis. In this study, a workflow was implemented, comprising the identification of new aptamers with high affinity for the ubiquitous surface protein A2 (UspA2) of the bacterial pathogen Moraxella catarrhalis and the development of an electrochemical biosensor functionalized with the best-performing aptamer as a bioreceptor to detect UspA2. After cell-systematic evolution of ligands by exponential enrichment (cell-SELEX) was performed, next-generation sequencing was used to sequence the final aptamer pool. The most frequent aptamer sequences were further evaluated using bioinformatic tools. The two most promising aptamer candidates, Apt1 and Apt1_RC (Apt1 reverse complement), had Kd values of 214.4 and 3.4 nM, respectively. Finally, a simple and label-free electrochemical biosensor was functionalized with Apt1_RC. The aptasensor surface modifications were confirmed by impedance spectroscopy and cyclic voltammetry. The ability to detect UspA2 was evaluated by square wave voltammetry, exhibiting a linear detection range of 4.0 × 104–7.0 × 107 CFU mL−1, a square correlation coefficient superior to 0.99 and a limit of detection of 4.0 × 104 CFU mL−1 at pH 5.0. The workflow described has the potential to be part of a sensitive PoC diagnostic platform to detect and quantify M. catarrhalis from biological samples.The study received financial support from the ViBrANT project, which received funding from the EU Horizon 2020 Research and Innovation Programme under the Marie Sklowdowska Curie, grant agreement no. 765042. In addition, the authors acknowledge the financial support from Fundação para a Ciência e Tecnologia (FCT) under the scope of the strategic funding of UID/BIO/04469/2020 unit and of LABBELS—Associate Laboratory in Biotechnology, Bioengineering and Microelectromechanical Systems, LA/P/0029/2020. D.L. and A.S. received additional funding from the Research Council of Norway (grant 294605, Center for Digital Life). L.D.R.M. acknowledges funding from the FCT through the Scientific Employment Stimulus Program (2021.00221.CEECIND).info:eu-repo/semantics/publishedVersio
(4R*,4aS*,4bS*,5R*,10aR*)-4-Hydroxy-4a,5-dimethyl-2-(propan-2-yl)-1,4,4a,4b,5,6,7,8,10,10a-decahydrophenanthren-1-one
In the title compound, C19H28O2, the A ring adopts a chair conformation. Both the B and C rings adopt envelope conformations with the C atoms common to both rings and adjacent to the carbonyl and hydroxyl groups, respectively, lying 0.604 (3) and 0.634 (3) Å out of the mean planes defined by the remaining five C atoms of rings B and C, respectively (r.m.s. deviations = 0.0100 and 0.0157 Å, respectively). The formation of linear supramolecular C(7) chains along the a axis mediated by hydroxy-O—H⋯O(carbonyl) hydrogen bonds is the most prominent feature of the crystal packing
Colonização e resistência antimicrobiana de Streptococcus pneumoniae isolado em nasofaringe de crianças com rinofaringite aguda
A simplified curcumin targets the membrane of Bacillus subtilis
Abstract Curcumin is the main constituent of turmeric, a seasoning popularized around the world with Indian cuisine. Among the benefits attributed to curcumin are anti‐inflammatory, antimicrobial, antitumoral, and chemopreventive effects. Besides, curcumin inhibits the growth of the gram‐positive bacterium Bacillus subtilis. The anti‐B. subtilis action happens by interference with the division protein FtsZ, an ancestral tubulin widespread in Bacteria. FtsZ forms protofilaments in a GTP‐dependent manner, with the concomitant recruitment of essential factors to operate cell division. By stimulating the GTPase activity of FtsZ, curcumin destabilizes its function. Recently, curcumin was shown to promote membrane permeabilization in B. subtilis. Here, we used molecular simplification to dissect the functionalities of curcumin. A simplified form, in which a monocarbonyl group substituted the β‐diketone moiety, showed antibacterial action against gram‐positive and gram‐negative bacteria of clinical interest. The simplified curcumin also disrupted the divisional septum of B. subtilis; however, subsequent biochemical analysis did not support a direct action on FtsZ. Our results suggest that the simplified curcumin exerted its function mainly through membrane permeabilization, with disruption of the membrane potential necessary for FtsZ intra‐cellular localization. Finally, we show here experimental evidence for the requirement of the β‐diketone group of curcumin for its interaction with FtsZ
Selection of novel peptides homing alternative targets in triple negative breast cancer
[Excerpt] Breast cancer is the most frequent cancer amongst women, representing 25% of all cancer cases, with an estimated 1.67 million new cases in 2012 1. Phenotypically characterized by the lack of known receptors, the triple negative breast cancer (TNBC) subtype is responsible for 10 to 20% of all diagnosed breast cancers 2. Due to its unique profile, aggressive behavior and different patterns of metastasis, the search for effective diagnosis and treatment tools has intensified 3. However, the lack of specific cell targeting remains the main barrier for sensitive diagnostic tools. [...]info:eu-repo/semantics/publishedVersio
Monitoramento e avaliação do risco de contaminação por pesticidas em água superficial e subterrânea na região de Guaíra
- …