H-bonding Interactions Research Articles

A dielectric, thermodynamic and volumetric investigation for heteromolecular hydrogen bonding in 2-ethoxyethanol and ethanol binary mixture

ABSTRACT The dielectric, thermodynamic and volumetric measurements of neat 2-ethoxyethanol, neat ethanol and their binary mixtures have been carried out using time domain technique at 10°C–25°C with a variation of 5°C. Various dielectric parameters are calculated from complex dielectric spectra and are used to compute Kirkwood correlation factor, Bruggeman factor and activation thermodynamic parameters. These parameters are used to predict heteromolecular hydrogen bonding between associating molecules. The classical and non-classical type H-bonding interactions among the molecules are predicted using FT-IR spectroscopy.

Discovery of α-amylase and α-glucosidase dual inhibitors from NPASS database for management of Type 2 Diabetes Mellitus: A chemoinformatic approach.

Postprandial hyperglycemia, typical manifestation of Type 2 Diabetes Mellitus (T2DM), is associated with notable global morbidity and mortality. Preventing the advancement of this condition by delaying the rate of glucose absorption through inhibition of α-amylase and α-glucosidase enzymatic activities is of utmost importance. Finding a safe antidiabetic drug is essential since those that are currently on the market have drawbacks like unpleasant side effects. The current study utilized computer-aided drug design (CADD), as a quick and affordable method to find a substitute drug template that can be used to control postprandial hyperglycemia by modulating the activity of α-amylase and α-glucosidase enzymes. The Natural Products Activity and Species database (NPASS) (30,926 compounds) was screened in silico, with a focus on evaluating drug-likeness, toxicity profiles and ability to bind on a target protein. Two molecules NPC204580 (Chrotacumine C) and NPC137813 (1-O-(2-Methoxy-4-Acetylphenyl)-6-O-(E-Cinnamoyl)-Beta-D-Glucopyranoside) were identified as potential dual inhibitors for α-amylase and α-glucosidase with free binding energies of -14.46 kcal/mol and -12.58 kcal/mol for α-amylase, and -8.42 kcal/mol and -8.76 kcal/mol for α-glucosidase, respectively. The molecules showed ionic, H-bonding and hydrophobic interactions with critical amino acid residues of both enzymes. Moreover, 100 ns molecular dynamic simulations showed that both molecules are stable on the receptors' active sites based on root mean square deviation (RMSD), root mean square fluctuation (RMSF), and the Generalized Born surface area (GBSA) energy calculated. The two compounds are thus promising therapeutic agents for T2DM that merit further investigation due to their excellent binding energies, encouraging pharmacokinetics, toxicity profiles, and stability as demonstrated in simulated studies.

Identification of novel inhibitors targeting PI3Kα via ensemble-based virtual screening method, biological evaluation and molecular dynamics simulation.

PIK3CA gene encoding PI3K p110α is one of the most frequently mutated and overexpressed in majority of human cancers. Development of potent and selective novel inhibitors targeting PI3Kα was considered as the most promising approaches for cancer treatment. In this investigation, a virtual screening platform for PI3Kα inhibitors was established by employing machine learning methods, pharmacophore modeling, and molecular docking approaches. 28 potential PI3Kα inhibitors with different scaffolds were selected from the databases with 295,024 compounds. Among the 28 hits, hit15 exhibited the best inhibitory effect against PI3Kα with IC50 value less than 1.0µM. The molecular dynamics simulation indicated that hit15 could stably bind to the active site of PI3Kα, interact with some residues by hydrophobic, electrostatic and hydrogen bonding interactions, and finally induced PI3Kα active pocket substantial conformation changes. Stable H-bond interactions were formed between hit15 and residues of Lys776, Asp810 and Asp933. The binding free energy of PI3Kα-hit15 was -65.3kJ/mol. The free energy decomposition indicated that key residues of Asp805, Ile848 and Ile932 contributed stronger energies to the binding free energy. The above results indicated that hit15 with novel scaffold was a potent PI3Kα inhibitor and considered as a promisingcandidateforfurther drugdevelopment to treat various cancers with PI3Kα over activated.

Physical and Chemical Dual Confinement Promotes Controllable Synthesis of Loose-Structured Azine-Linked Nanofilms for Fast Molecular Separation.

Thin-film composite (TFC) membranes, featuring nanoscale film thickness and customizable pore structures, hold promise for solute-solute separations. However, achieving on-demand molecular sieving requires fine control over the membrane microstructure. Here, the concept of physical and chemical dual confinement (PCDC) is introduced to fabricate loose-structured TFC membranes via confined interfacial polymerization (IP). This concept leverages the synergistic effects of physically restricted monomer diffusion and a chemically inhibited reaction to achieve controlled nanofilm growth. Dorsal addition of the aqueous phase to the hydrogel reduces the diamine diffusion via electrostatic and H-bonding interactions within its nanopores. The prepassivation of hydrazine using acid protonation effectively weakens its ability for nucleophilic reactivity. This confined IP between twisted TFPA and short-chain hydrazine yielded loosely structured azine-linked nanofilms, which displayed a high permeability of 53.4 LMH bar-1 and effective differentiation of binary mixtures. This PCDC concept offers a useful guideline to finely tailor polymeric nanofilms for precise separations.

Acetylacetone – 2-methoxyethanol solutions: Fourier transform infrared spectral studies

The H-bond interactions in the solutions of acetylacetone (AcAc) with 2-methoxyethanol (2-MOE) have been investigated using FTIR spectroscopy. Theoretical calculations on monomers (eight enol isomers and one keto form) and dimers of AcAc have been carried out. The results confirm that both the keto and enol forms of AcAc exist as monomers in liquid AcAc. The analysis of the carbonyl and hydroxyl bands indicates the existence of both the AcAc conformers in the solutions. The intensity of the bands due to the hydroxyl stretching and in-plane bending vibrations decreases rapidly with a decrease in 2-MOE concentration.

A Study on the Stability of High Drug Solubility Characteristics of Hydroxyphenyl Adhesives under the Interference of CPEs.

Novel hydroxyphenyl adhesives (HP-PSAs) could significantly increase drug solubility and control drug release through a doubly ionic hydrogen bond (DIH bond) in the patch. However, chemical penetration enhancers (CPEs) always destroy the performance of most adhesives. As a result, this work investigated the stability of both the HP-PSA features and the DIH bond under the interference of the CPEs. Donepezil (DON) was chosen as the model drug, and CPEs with hydroxyl, carboxyl, amido, and ester groups were selected as model CPEs. Unlike the commonly used neutral H-bond, the DIH bond between DON and the HP-PSA was still stable under the interference of the CPEs, resulting in the 2-3-fold drug solubility in the HP-PSA, which was higher than that in the nonfunctional PSA, which reduced the drug crystallization risk and the difficulty of formulation design. FT-IR, 1H NMR, XPS, dynamic simulation, and molecular docking revealed the mechanism of the stability feature of both the DIH bond and the high drug solubility of the HP-PSA, which was that the formed neutral H-bond interaction caused by CPEs is weaker than that of the DIH bond between DON and the HP-PSA. Furthermore, the drug release, skin permeation, and CPE release study showed that the newly formed weak H-bond and strong ionic H-bond interaction promoted or controlled both DON and CPE release, respectively, thereby influencing drug skin permeation, which provided a theoretical basis for drug release regulation. To summarize, besides the reversible, strong features of the DIH bond in our previous study, the stability of the interaction made the HP-PSA's high drug solubility potential to be applied in the TDDS.

Bro̷nsted Acid-Catalyzed Regioselective [5 + 1] Annulation for the Synthesis of Indole-Fused Dihydrochromanes.

A Bro̷nsted acid-catalyzed [5 + 1] annulation of 2-(1H-indol-2-yl)phenols, a class of indole-based 1,5-CO-synthons, with aldehydes has been established. By this approach, various indole-fused dihydrochromanes were synthesized in moderate to good yields (up to 99%) with excellent regioselectivities. Control experiments not only showed the H-bonding interaction between the NH group of the substrates─and the acid catalyst is vital to realize this transformation─but also indicated that an indolylmethanol-type intermediate was possibly formed via the first step of nucleophilic addition of indole C3-position to aldehydes during the reaction process. This reaction represents the first Bro̷nsted acid-catalyzed regioselective [5 + 1] annulation of 2-(1H-indol-2-yl)phenols and provides a novel strategy for constructing biologically intriguing indole-fused dihydrochromane skeletons in a highly regioselective manner.

Microscopic water dispersion and hydrogen-bonding structures in margarine spreads with Raman hyperspectral imaging and machine learning

Margarine, a water-in-oil (W/O) emulsion, offers advantages such as lower costs in comparison to similar products, but large amounts of saturated fats pose health risks. Reduction of saturated fat content is difficult and often leads to “oil-off,” i.e., the seepage of liquid oil from the mixture, resulting in undesirable appearance and texture. Investigations into the phenomenon have often focused on morphology at the water-oil interfaces, and this work establishes Raman imaging as a powerful application for observing microscopic morphologies of W/O emulsions. We analyze morphologies of 5 distinct margarine spreads that differ in manufacturing date, formulation, and manufacturing process. More robust H-bonding in the oil phase of the emulsions co-occurred with smaller amounts of oil-off, suggesting that H-bonding interactions between emulsifier molecules, water, and crystallized fats in the lipid phase of the W/O emulsions results in an emulsion that is less susceptible to the production of oil-off.

Hydroxylated SiO2-modified {0 0 1}-TiO2 nanosheets as a surface multifunctional photocatalyst for enhanced degradation of gaseous toluene

The relatively weak activity and serious deactivation of anatase TiO2 nanosheet catalysts with highly exposed {001} facets ({001}-TiO2) limits its wide application in photocatalytic degradation of gaseous pollutants. Herein, we propose a hybrid photocatalyst composed of {001}-TiO2 and SiO2 with numerous hydroxyl groups (denoted as {001}-TiO2/HO-SiO2). The catalyst showed excellent performance for gaseous toluene degradation under UV illumination, with 99.2 % removal efficiency and 204.7 μmol L−1 CO2 yield (about 85.9 % mineralization efficiency) within 120 min. It also demonstrated superior durability over five consecutive cycles of toluene photodegradation. The modification of HO–SiO2 on {001}-TiO2 facilitate the selective adsorption of toluene on the catalyst surface by H-bonding interaction, and make the major poisoning species, benzoic acid, easily desorb from the surface, reducing the catalyst inactivation. Most importantly, we found that the formed TiOSi bond promotes the separation of photogenerated electron–hole pairs, and provides abundant available electrons for the formation of reactive oxygen radicals and the left holes for the conversion of toluene to benzyl radicals or oxidation of H2O to hydroxyl radicals, which results in the improved activity. This study highlights the importance of the introduction of secondary components with special functions on TiO2, which is helpful for the design of photocatalysts with high performance and anti-deactivation ability for treatment of volatile organic compounds.

Supramolecular architectures, Hirshfeld surfaces analysis, spectroscopic, computational and photovoltaic properties of nickel(II) binary and ternary complexes of N-phenethyl-iminodiacetate (2-) chelate

The bluish-green color nickel(II) binary and/or ternary compounds have been isolated from the solution of stoichiometric reaction between Ni(II) hydroxy-carbonate and N-phenethyl-iminodiacetic acid (H2pheida) chelating ligand in aqueous media with compound (2); [Ni(pheida)(Him)3]·4H2O and without imidazole compound (1); [Ni(pheida)(H2O)3]. The crystal pattern of binary compound [Ni(pheida)(H2O)3] (1) differs from the related tetra-hydrated ternary complex of [Ni(pheida)(Him)3]·4H2O (2) can be attributed to the presence of stronger N-(Him) spacer of imidazole ligand. The compounds reported herein, have been characterized by means of elemental analysis, FTIR, UV–vis, TGA and X-ray crystallography. Moreover, the distinctive inter-molecular forces particularly H-bonding interactions, 2D fingerprint plots and supramolecular architecture have been studied using Hirshfeld surface analysis. The nickel(II) binary and ternary complexes (1) and (2) show distorted octahedral geometry around the Ni(II) ion of the type 1 + 2 + 2 + 1 imposed by 3d8 electronic configuration with degenerate fully and half occupied t2g6 and eg2 orbitals respectively. The higher John-Teller distortion has been observed for complex (2) than that of complex (1). The IDA arm of chelate adopted fac-NO2 conformation in both complexes (1) and (2). Moreover, the photovoltaic properties as semiconducting nature for ligand and their corresponding Ni(II) complexes were estimated using Tauc’s equation, αhν = A(hν-Eg)r, where r = ½ for indirect and 2 for direct electronic transitions through UV–vis absorption data. The indirect and direct electronic transition bandgap (Eg) calculated for complex (1) is 2.0 and 3.07 eV respectively. Similarly, 2.55 and 4.39 eV respectively measured for complex (2).

Highly selective separation of 99TcO4−/ReO4− with rapid liquid-liquid two-phase disengagement by amine-diamide ligands

Efficient and selective extraction of pertechnetate (TcO4−) from nitric acid medium has become a significant challenge, especially in the presence of a large excess of interfering anions. By employing a combined strategy involving H-bonding and electrostatic interaction, a highly selective extraction of TcO4− can be achieved. The present work reports three homologous amine-diamide ligands with different alkyl chain lengths on the amine N atom of 2,2′‐(metylimino)bis(N,N‐dioctylacetamide) (MIDOA), 2,2′‐(butylimino)bis(N,N‐dioctylacetamide) (BIDOA) and 2,2′‐(octylimino)bis(N,N‐dioctylacetamide) (OIDOA), and their extraction behaviors for TcO4−/ReO4− in HNO3 solution are also investigated by using n-dodecane as a diluent. It has been shown that all of them exhibit excellent extractability and high selectivity to TcO4−/ReO4−. Their extractability and phase disengagement follow the order of OIDOA > BIDOA > MIDOA, revealing a greater extractability and rapider phase disengagement for the amine-diamide ligand with longer chain substituents on the amine N atom. Both slope analysis and loading capacity test indicate the formation of 1:1 metal/ligand extracted complex, which is also confirmed by the analyses of single-crystal X-ray diffraction (SC-XRD), electrospray ionization mass (ESI-MS), Fourier transform infrared (FT-IR), and X-ray photoelectron spectroscopy (XPS). The extraction of TcO4−/ReO4− by the amine-diamide ligand follows the anion exchange extraction model and is a spontaneous and endothermic process. Furthermore, a competing extraction test was also conducted and demonstrates excellent extractability and high selectivity to TcO4−/ReO4−.

Fabrication and application of aminated metal–organic cages doped monolithic column for pipette tip micro solid-phase extraction of eight phenolic compounds in milk

A Zr-based metal–organic tetrahedron (ZrT-1-NH2) doped monolithic column was sythesized and applied for pipette tip micro solid-phase extraction (PT-μSPE) of 8 phenolic compounds. Scanning electron microscopy, energy dispersive spectrometry, Fourier transform infrared spectroscopy, thermogravimetric analysis and N2 adsorption and desorption experiment were employed to characterize the morphology, composition, structure and thermal stability of the monolithic column. The experimental results showed that the monolithic column had good stability and excellent adsorption selectivity for phenolic compounds. The adsorption mechanism was speculated to be π-π stacking and H-bond interaction based on ESP maps. After the extraction conditions were optimized, a PT-μSPE-high performance liquid chromatography-ultraviolet detector (HPLC-UV) method was established for the detection of 8 phenolic compounds in milk. The PT-μSPE-HPLC-UV method has wide linearities (0.3–1000 μg L−1) (R2 > 0.997), low limits of detection (0.1–0.3 μg L−1), satisfactory recoveries (80.5–113.6 %) and high precision (RSDs < 6.7 %). Thus, the ZrT-1-NH2 doped monolithic column is an ideal medium for the separation and determinaton of phenolic compounds in milk.

Synthesis, Biological Evaluation, Molecular Docking Studies and ADMET Prediction of Oxindole-Based Hybrids for the Treatment of Tuberculosis.

With a projected mortality toll of 1.4 million in 2019, tuberculosis (TB) continues to be a significant public health concern around the world. Studies of novel treatments are required due to decreased bioavailability, increased toxicity, increased side effects, and resistance of several first- and second-line TB therapies, including isoniazid and ethionamide. This study reports the synthesis of oxindole-based hybrids as potent InhA inhibitors targeting Mycobacterium tuberculosis. The synthesized compounds (5a-5e and 8a-8c) were evaluated for their anti-mycobacterial activity against Mycobacterium tuberculosis and nontuberculous mycobacteria (NTMs), viz. M. abscessus (ATCC 19977), M. fortuitum (ATCC 6841), and M. chelonae (ATCC 35752) using the Microplate Alamar Blue Assay (MABA). Molecular docking studies were performed using AutoDock Vina to explore the binding interactions of these compounds with the InhA enzyme (PDB: 2NSD). Additionally, biochemical and histopathological studies were conducted to assess the hepatotoxicity of the lead compounds. Insilico molecular properties and ADMET properties of the synthesized compounds were predicted using SwissADME and Deep-PK online tools to assess their drug-likeness. Among the tested compounds, 8b exhibited significant anti-mycobacterial activity with a minimum inhibitory concentration (MIC = 1 μg/mL) comparable to the reference drug ethambutol. Further, the compound demonstrated a binding affinity and orientation similar to the reference inhibitor 4PI, indicating its potential as a potent InhA inhibitor, and was found to be stabilized within the binding pocket of InhA through H-bonding, hydrophobic and van der Waal's interactions. Besides, the compounds hepatotoxicity assessment studies depicted that 8b showed no significant liver dysfunction or damage to liver tissues. Additionally, 8b adhered to Lipinski's rule of five and Veber's rule, displaying favourable pharmacokinetic and drug-like properties, including high human intestinal absorption, distribution, and acceptable metabolic stability and excretion. Compound 8b emerged as a promising candidate for further optimization and development as a therapeutic agent for tuberculosis, offering a new avenue for tackling tuberculosis.

Structural Design, H-Bonding Interactions, Vibrational Properties, Periodic-DFT Calculations, and Antibacterial Activity of a Nicotinamide Cocrystal Using Tetradecanoic Acid as a Coformer

Structural Design, H-Bonding Interactions, Vibrational Properties, Periodic-DFT Calculations, and Antibacterial Activity of a Nicotinamide Cocrystal Using Tetradecanoic Acid as a Coformer

Robust and Reversible Thermal/Electro-Responsive Supramolecular Polymeric Adhesives via Synergistic Hydrogen-Bonds and Ionic Junctions.

Adhesive conducting elastomers are rising materials towards cutting-edge applications in wearable and implantable soft electronics. Yet, engineering the conductive adhesives with robust and tunable interfacial bonding strength is still in its infancy stage. We herein identify a structurally novel supramolecular polymer scaffold, characterized by synergistic coexistence of hydrogen-bonding (H-bonding) interactions and electrostatic ionic junctions, endowing the robust and tunable elastic conducting adhesives with remarkable thermal/electro-responsive performance. H-bonding association and electrostatic interaction play orthogonal yet synergistic roles in the strong supramolecular adhesive formation, serving as the leveraging forces for opposing both cohesion and adhesion energy. To do so, six-arm star-shaped random copolymers P(DAP-co-Thy-co-MBT)6 are strategically designed, bearing H-bonding PDAP (poly(diaminopyridine acrylamide)) and PThy (poly(thymine)) segments, which can form hetero-complementary DAP/Thy H-bonding association, along with conductive poly(ionic liquid)s segment: PMBT, (poly(1-[2-methacryloylethyl]-3-methylimidazolium bis(trifluoromethane)-sulfonamide)). DAP/Thy H-bonding association, along with electrostatic ionic interaction, can yield dual supramolecular forces crosslinked polymeric networks with robust cohesion energy. Moreover, coexistence of poly(ionic liquid)s can impact and interfere the configuration of H-bonding association, liberate more free DAP and Thy motifs to form H-bonds towards substrate, affording strong surface adhesion in a synergistic manner. This work demonstrates a significant forward step towards potential adhesives devoted to hybrid electronic devices.

Efficient Deep-Blue Fluorescent OLEDs Based on a D-π-A Emitter Profiting From Intramolecular Hydrogen Bonds and a Hybridized Excited State.

High performance deep-blue emitters with a Commission International de l'Eclairage (CIE) coordinate of CIEy≤0.08 are highly desired in ultrahigh-definition displays. Herein, we designed and synthesized an efficient D-π-A deep-blue emitter, 2-(6-([1,1' : 3',1''-terphenyl]-5'-yl)pyridin-3-yl)-1-phenyl-1H-phenanthro[9,10-d] imidazole (mPTPH), using the synergistic effect of intramolecular hydrogen bond (H-bond) and hybridized excited state. Single-crystal structure analysis confirmed that there exist intra- and intermolecular H-bond interactions which could inhibit the structure vibration and increase photoluminescence efficiency. The photophysical and theoretical results show that mPTPH exhibited hybridized local and charge-transfer (HLCT) feature with strong deep-blue emission. Ultimately, the non-doped device based on mPTPH exhibited high maximum luminance of 20610 cd m-2. The doped device achieved high maximum external quantum efficiency of 5.4 % and small efficiency roll-off with deep-blue emission peak of 413 nm and CIE coordinate of (0.16, 0.08).

New Hypothesis on Enhancing β-Sheet Formation during the Tau Fragment Dimer Transition from a Flexible Monomer: Insights into Primary Nucleation Processes by Histidine Behaviors.

Slight perturbations in pH can have significant effects on the primary nucleation processes of the tau protein. The behaviors of histidine due to its pivotal role in modulating H-bonding network interactions and electrostatic interactions have garnered considerable attention, as it can influence the structural characteristics and aggregation properties. However, the nucleation mechanisms and related intermediates are still unclear. In the current study, we performed nine independent replica exchange molecular dynamics simulations to investigate dimer formation involving R3(εδ) in conjunction with the R1, R2, and R4 monomers. Our findings substantiate that, in comparison to R1-R3(εδ) and R4-R3(εδ) systems, the R2-R3(εδ) systems consistently manifest the highest averaged β-sheet content, with the fundamental feature of R3(εδ) promoting R2 rearrangement. Our comprehensive analysis reveals that high-β-sheet-rich systems exhibit a conserved three/five β-strand structure. In these β-strand-rich systems, one chain [R1/R2/R4 or R3(εδ)] with robust intrachain H-bonding interactions coordinates with another chain through interchain H-bonding interactions, contributing to the overall stability. Furthermore, we discuss distinct histidine behaviors, including backbone/side chain interactions and donor/acceptor roles. This study provides a comprehensive understanding of the aggregation propensities of soluble tau oligomers and sheds light on the primary nucleation mechanism. It contributes to a new perspective for understanding protein folding and misfolding.

Synchronous Modulation of H-bond Interaction and Steric Hindrance via Bio-molecular Additive Screening in Zn Batteries.

In addressing challenges such as side reaction and dendrite formation, electrolyte modification with bio-molecule sugar species has emerged as a promising avenue for Zn anode stabilization. Nevertheless, considering the structural variability of sugar, a comprehensive screening strategy is meaningful yet remains elusive. Herein, we report the usage of sugar additives as a representative of bio-molecules to develop a screening descriptor based on the modulation of the hydrogen bond component and electron transfer kinetics. It is found that xylo-oligosaccharide (Xos) with the highest H-bond acceptor ratio enables efficient water binding, affording stable Zn/electrolyte interphase to alleviate hydrogen evolution. Meanwhile, sluggish reduction originated from the steric hindrance of Xos contributes to optimized Zn deposition. With such a selected additive in hand, the Zn||ZnVO full cells demonstrate durable operation. This study is anticipated to provide a rational guidance in sugar additive selection for aqueous Zn batteries.

Factor XIII Activation Peptide Residues Play Important Roles in Stability, Activation, and Transglutaminase Activity.

A subunit of factor XIII (FXIII-A) contains a unique activation peptide (AP) that protects the catalytic triad and prevents degradation. In plasma, FXIII is activated proteolytically (FXIII-A*) by thrombin and Ca2+ cleaving AP, while in cytoplasm, it is activated nonproteolytically (FXIII-A°) with increased Ca2+ concentrations. This study aimed to elucidate the role of individual parts of the FXIII-A AP in protein stability, thrombin activation, and transglutaminase activity. Recombinant FXIII-A AP variants were expressed, and SDS-PAGE was used to monitor thrombin hydrolysis at the AP cleavage sites R37-G38. Transglutaminase activities were assessed by cross-linking lysine mimics to Fbg αC (233-425, glutamine-substrate) and monitoring reactions by mass spectrometry and in-gel fluorescence assays. FXIII-A AP variants, S19P, E23K, and D24V, degraded during purification, indicating their vital role in FXIII-A2 stability. Mutation of P36 to L36/F36 abolished the proteolytic cleavage of AP and thus prevented activation. FXIII-A N20S and P27L exhibited slower thrombin activation, likely due to the loss of key interdomain H-bonding interactions. Except N20S and P15L/P16L, all activatable FXIII-A* variants (P15L, P16L, S19A, and P27L) showed similar cross-linking activity to WT. By contrast, FXIII-A° P15L, P16L, and P15L/P16L had significantly lower cross-linking activity than FXIII-A° WT, suggesting that loss of these prolines had a greater structural impact. In conclusion, FXIII-A AP residues that play crucial roles in FXIII-A stability, activation, and activity were identified. The interactions between these AP amino acid residues and other domains control the stability and activity of FXIII.

Molecular Interactions between Kaempferol and Apolipoprotein A-I (APOA1) of Rattus Norvegicus of Using Drug Docking

Nowadays, pharmacological research investigations are essential to the development of new medication prospects. We have created high-resolution synteny and rearrangement breakpoint maps across the human, mouse, and rat genomes using paired-end sequences from bacterial artificial chromosomes. Apolipoprotein A-I (APOA1) is often associated with a markedly elevated risk of atherosclerosis and cardiovascular disease. Several studies in the field of clinico-genetics have confirmed this fact. In this work, we employ 3D Insilico drug docking techniques to simulate kaempferol interactions with the potential mutant target protein Apolipoprotein A-I (APOA1). Kaempferol is one of the primary phytochemicals present in Hibiscus rosa-sinensis. Numerous pharmacological effects of Hibiscus rosa-sinensis have been shown to be effective in treating a wide spectrum of human ailments. We look into the connection between APOA1 and kaempferol. In post-docking tests, advanced 3D molecular visualization capabilities were utilized. Kaempferol directly reduces amino acid mutational sites, as indicated by the docking study results. The molecular 3D H-bond interaction between APOA1 and Kaempferol is illustrated using concepts of molecular dynamics techniques based on 3D views. Docking studies play a key role in pharmaceutical researches for the production of novel drug candidates. Thus, investigations on Rattus norvegicus with kaempferol plays a significant role in the pharmacological industry in designing innovative medication candidates. Lastly, we conclude that kaempferol is protective against cardiovascular diseases associated with atherosclerosis.