Notes![what is notes.io? What is notes.io?](/theme/images/whatisnotesio.png)
![]() ![]() Notes - notes.io |
A new application of stimulated Raman scattering (SRS) uses the benefit of a label-free molecular fingerprint to image the uptake and distribution of an alkyne-based drug in living cells. This method delivers information on cellular molecular composition and drug-cell interaction, showing the potential of SRS in drug development.Bimolecular nucleophilic substitution (SN2) reactions are of great importance in chemistry and biochemistry due to their capability of constructing functional groups. In this work, we investigate the solvent effect on the free energy profiles of symmetric and asymmetric SN2 reactions in the acetonitrile solution using the proposed reaction density functional theory (RxDFT) method. This multiscale method utilizes quantum density functional theory for calculating intrinsic reaction free energy coupled with classical density functional theory for addressing solvation contribution. We find that the presence of acetonitrile brings both the polarization effect and solvation effect on the reaction pathways. For the eight selected symmetric SN2 reactions, the predicated reaction pathways agree well with the results from the direct and thermodynamic cycle (TC) methods with the SMD-M062X solvation model. In addition, the polarization effect reduces the free energy barriers by about 6 kcal/mol, while the solvation effect increases the barriers by about 18 kcal/mol. For the four selected asymmetric SN2 reactions, the predicted reaction pathways agree well with the results from the Monte Carlo simulations and experiments. The polarization effect and the solvation effect mutually reduce the free energy barriers, and the solvation effect plays a dominant role.Nanometer-sized features and molecular recognition properties make DNA a useful material for nanoscale construction, but degradation in biological fluids poses a considerable roadblock to biomedical applications of DNA nanotechnology. Here, we report the remarkable biostability of a multistranded motif called paranemic crossover (PX) DNA. Compared to double stranded DNA, PX DNA has dramatically enhanced (sometimes >1000 fold) resistance to degradation by four different nucleases, bovine and human serum, and human urine. We trace the cause of PX's biostability to DNA crossovers, showing a continuum of protection that scales with the number of crossovers. These results suggest that enhanced biostability can be engineered into DNA nanostructures by adopting PX-based architectures or by strategic crossover placement.Squalene synthase (SQS) catalyzes the conversion of two farnesyl pyrophosphates to squalene, an important intermediate in between isoprene and valuable triterpenoids. In this study, we have constructed a novel biosynthesis pathway for squalene in Bacillus subtilis and performed metabolic engineering aiming at facilitating further exploitation and production of squalene-derived triterpenoids. Therefore, systematic studies and analysis were performed including selection of multiple SQS candidates from various organisms, comparison of expression vectors, optimization of cultivation temperatures, and examination of rate-limiting factors within the synthetic pathway. We were, for the first time, able to obtain squalene synthesis in B. subtilis. Furthermore, we achieved a 29-fold increase of squalene yield (0.26-7.5 mg/L) by expressing SQS from Bacillus megaterium and eliminating bottlenecks within the upstream methylerythritol-phosphate pathway. Moreover, our findings showed that also ispA could positively affect the production of squalene.As emerging alternatives of legacy perfluoroalkyl substances, 62 fluorotelomer sulfonate (62 FTS), 62 chlorinated polyfluoroalkyl ether sulfonates (62 Cl-PFESA), and perfluorophosphinates (C6/C6 and C8/C8 PFPiAs) are supposed to be partitioned to soil and highly persistent in the environment. The uptake of novel per- and polyfluoroalkyl substances (PFASs) by plants represents a potential pathway for their transfer in the food chain. In this study, the bioavailability of these four novel PFASs in soil and the bioaccumulation characteristics in greenhouse-grown wheat (Triticum aestivum L.), maize (Zea mays L.), soybean (Glycine max L. Merrill), and pumpkin (Cucurbita maxima L.) were investigated. The results indicated that these novel PFASs with higher hydrophobicity were more easily sequestrated in soil, and the fractions extracted by methanol could well describe their bioavailability, which could be stimulated by low-molecular-weight organic acids at rhizospheric concentrations. A negative relationship was found between root soil concentration factors (RSCFs) and hydrophobicity (log Kow) of the target PFASs. This correlation was also found in the translocation factors (TF) from roots to shoots. Furthermore, the uptake and transfer of the target PFASs were regulated by the protein contents in plant roots and shoots.Long-chain acyl-coenzyme A (CoA) synthetase (LACS) catalyzes the formation of acyl-CoAs from free fatty acids, which is pivotal for lipid metabolism. https://www.selleckchem.com/products/isa-2011b.html Here, we confirmed the presence of six CzLACS genes in Chromochloris zofingiensis. Functional complementation and in vitro enzymatic assay indicated that CzLACS2 through CzLACS5 rather than CzLACS1 or CzLACS6 are bona fide LACS enzymes and they have overlapping yet distinct substrate preference. The results of the subcellular colocalization experiment and different expression patterns under three triacylglycerol (TAG)-inducing conditions showed that CzLACS2 through CzLACS4 reside at endoplasmic reticulum (ER) and are involved in TAG biosynthesis, while CzLACS5 resides in peroxisome and participates in fatty acid β-oxidation. The yeast one-hybrid assay using a library of 50 transcription factors (TFs) constructed in our study identified 12 TFs potentially involved in regulating the expression of CzLACSs. Moreover, heterologous expression of CzLACSs demonstrated their engineering potential for modulating TAG synthesis in yeast and algal cells.Proteins are a substantial nitrogen source in soils provided that they can be hydrolyzed into bioavailable small peptides or amino acids. However, the strong associations between proteins and soil minerals restrict such proteolytic reactions. This study focused on how an extracellular fungal protease (Rhizopus sp.) hydrolyzed iron oxide-associated bovine serum albumin (BSA) and the factors that affected the proteolysis. We combined batch experiments with size-exclusion and reversed phase liquid chromatography and in situ infrared spectroscopic measurements to monitor the generation of proteolytic products in solution as well as the real-time changes of the adsorbed BSA during 24 h. Results showed that protease hydrolyzed the iron oxide-associated BSA directly at the surface without an initial desorption of BSA. Concurrently, the protease was adsorbed to vacant surface sites at the iron oxides, which significantly slowed down the rate of proteolysis. This inhibiting effect was counteracted by the presence of preadsorbed phosphate or by increasing the BSA coverage, which prevented protease adsorption.
My Website: https://www.selleckchem.com/products/isa-2011b.html
![]() |
Notes is a web-based application for online taking notes. You can take your notes and share with others people. If you like taking long notes, notes.io is designed for you. To date, over 8,000,000,000+ notes created and continuing...
With notes.io;
- * You can take a note from anywhere and any device with internet connection.
- * You can share the notes in social platforms (YouTube, Facebook, Twitter, instagram etc.).
- * You can quickly share your contents without website, blog and e-mail.
- * You don't need to create any Account to share a note. As you wish you can use quick, easy and best shortened notes with sms, websites, e-mail, or messaging services (WhatsApp, iMessage, Telegram, Signal).
- * Notes.io has fabulous infrastructure design for a short link and allows you to share the note as an easy and understandable link.
Fast: Notes.io is built for speed and performance. You can take a notes quickly and browse your archive.
Easy: Notes.io doesn’t require installation. Just write and share note!
Short: Notes.io’s url just 8 character. You’ll get shorten link of your note when you want to share. (Ex: notes.io/q )
Free: Notes.io works for 14 years and has been free since the day it was started.
You immediately create your first note and start sharing with the ones you wish. If you want to contact us, you can use the following communication channels;
Email: [email protected]
Twitter: http://twitter.com/notesio
Instagram: http://instagram.com/notes.io
Facebook: http://facebook.com/notesio
Regards;
Notes.io Team