Structure Of Fragment Research Articles

Prediction of DNA-binding Sites in Transcriptions Factor in Fur-like Proteins Using Machine Learning and Molecular Descriptors

Introduction: Transcription factors are of great interest in biotechnology due to their key role in the regulation of gene expression. One of the most important transcription factors in gramnegative bacteria is Fur, a global regulator studied as a therapeutic target for the design of antibacterial agents. Its DNA-binding domain, which contains a helix-turn-helix motif, is one of its most relevant features. Methods: In this study, we evaluated several machine learning algorithms for the prediction of DNA-binding sites based on proteins from the Fur superfamily and other helix-turn-helix transcription factors, including Support-Vector Machines (SVM), Random Forest (RF), Decision Trees (DT), and Naive Bayes (NB). We also tested the efficacy of using several molecular descriptors derived from the amino acid sequence and the structure of the protein fragments that bind the DNA. A feature selection procedure was employed to select fewer descriptors in each case by maintaining a good classification performance. Results: The best results were obtained with the SVM model using twelve sequence-derived attributes and the DT model using nine structure-derived features, achieving 82% and 76% accuracy, respectively. Conclusion: The performance obtained indicates that the descriptors we used are relevant for predicting DNA-binding sites since they can discriminate between binding and non-binding regions of a protein.

2,2- dimethylbenzopyran derivatives containing pyridone structural fragments as selective dual-targeting inhibitors of HIF-1α and EZH2 for the treatment of lung cancer

We formerly reported that EZH2 inhibitors sensitized HIF-1 inhibitor-resistant cells and inhibited HIF-1α to promote SUZ12 transcription, leading to enhanced EZH2 enzyme activity and elevated H3K27me3 levels, and conversely, inhibition of EZH2 promoted HIF-1α transcription. HIF-1α and EZH2 interacted to form a negative feedback loop that reinforced each other's activity. In this paper, a series of 2,2- dimethylbenzopyran derivatives containing pyridone structural fragments were designed and synthesized with DYB-03, a HIF-1α inhibitor previously reported by our group, and Tazemetostat, an EZH2 inhibitor approved by FDA, as lead compounds. Among these compounds, D-01 had significant inhibitory activities on HIF-1α and EZH2. In vitro experiments showed that D-01 significantly inhibited the migration of A549 cells, clone, invasion and angiogenesis. Moreover, D-01 had good pharmacokinetic profiles. All the results about compound D-01 could lay a foundation for the research and development of HIF-1α and EZH2 dual-targeting compounds.

An overview of chatbots in tourism and hospitality using bibliometric and thematic content analysis

PurposeArtificial intelligence is one of the most significant and active fields of study in the last few years. Artificial intelligence-derived robotic technologies known as chatbots are gaining interest from both academic and industry sectors. By analyzing the development and patterns of research on the chatbot phenomena within the tourism field, this study seeks to develop a theoretical framework for the interaction between chatbots and tourism.Design/methodology/approachThe Web of Science (WoS) database’s 33 articles on chatbots related to travel and hospitality were examined between 2019 and 2024 using VOSviewer software for bibliometric and thematic content analysis.FindingsResearch on chatbots for tourism and hospitality appears to be in its early stages. The factors influencing tourists' intentions to use chatbots have been thoroughly researched; the attitudes, perceptions and behavioral intentions of destinations, travel agencies and restaurant patrons regarding chatbots were examined, and it was found that the quantitative research approach was dominant. In addition, the majority of the studies are based on a particular theory or model.Originality/valueThis is one of the first attempts to directly comprehend and depict the interconnected structures of studies on the interaction between chatbots and tourism through the use of network analysis. Furthermore, the study’s findings can offer academics a comprehensive viewpoint and a reference manual for more accurate assessment and oversight of the chatbot-tourism interaction. Regarding the lack of research on the topic and the fragmented structure of the studies that exist, it is imperative to provide both a comprehensive overview and a roadmap for future investigations into the usage of chatbots in the travel and hospitality sector.

SVhawkeye: an ultra-fast software for user-friendly visualization of targeted structural fragments from BAM files.

SVhawkeye is a novel visualization software created to rapidly extract essential structural information from third-generation sequencing data, such as data generated by PacBio or Oxford Nanopore Technologies. Its primary focus is on visualizing various structural variations commonly encountered in whole-genome sequencing (WGS) experiments, including deletions, insertions, duplications, inversions, and translocations. Additionally, SVhawkeye has the capability to display isoform structures obtained from iso-seq data and provides interval depth visualization for deducing local copy number variation (CNV). One noteworthy feature of SVhawkeye is its capacity to genotype structural variations, a critical function that enhances the accuracy of structural variant genotyping. SVhawkeye is an open-source software developed using Python and R languages, and it is freely accessible on GitHub (https://github.com/yywan0913/SVhawkeye).

Dynamic In Vitro Gastric Digestion Behaviour of Commercial Infant Formulae Made with Cow, Goat and Sheep Milk.

There are a wide range of commercial infant formulae available on the market. These are made using milk from different species, such as goat, sheep, and cow. The different protein compositions of these milks and the process used during infant-formulae manufacture, such as heat treatment, may impact the digestion of nutrients. This study compared the effect of protein composition and heat treatment on the in vitro gastric digestion behaviour of commercial infant formulae made with cow, goat, and sheep milk using a dynamic infant human gastric simulator (IHGS). During the simulated dynamic gastric digestion, the goat milk infant formula (GIF) showed earlier signs of aggregate formation compared to cow milk infant formula (CIF) and sheep milk infant formula (SIF). In addition, the microstructures of GIF chyme showed fragmented and porous structures. On the contrary, CIF formed dense protein networks that trapped oil droplets, whereas SIF exhibited a microstructure of smooth oil droplets surrounded by fewer protein networks. The different aggregation behaviours and aggregate structures of the three infant-formulae chyme were related to their different protein compositions, especially the different casein compositions. Furthermore, the open fragile structure of GIF aggregates provided easier access to pepsin, allowing it to hydrolyse protein. The results from the present study provided some information to assist in understanding the coagulation and digestion behaviours of commercial infant formulae made from different species of milk.

Efficient hydrolysis of cellulose into sugars in aqueous systems using fibrous core-shell structure FS@C/HPW

Phosphotungstic acid hydrate (HPW)-doped hydroxyl-rich hydrothermal carbon-coated fibrous silica catalyst (FS@C/HPW) is fabricated to induce the highly efficient hydrolysis of cellulose to sugar in an ultra-low acid aqueous system. The obtained FS90@C/HPW12 owns good thermal stability under 200 °C and the highest specific surface area at 28 m2/g. Owing to its special fibrous microstructures, FS90@C/HPW12 can cause linear damage and structural fragmentation on the surface of cellulose during hydrolysis. Accordingly, rather highly efficient hydrolysis with the cellulose conversion of 100 %, total reducing sugar and glucose yields at 92.2 % and over 85 % is achieved in the aqueous system with FS90@C/HPW12 and 5 mmol/L H2SO4. FS90@C/HPW12 also exhibits good reusability in multiple hydrolysis. This research provides a particular way for the design and synthesis of solid catalysts to induce the highly efficient hydrolysis of cellulose to sugar by chemical catalysis in a full aqueous system.

Strengthening effect of monolayer graphene oxide on the impact mechanical properties of concrete and the mechanism analysis based on fractal theory

Graphene oxide (GO), a new nanomaterial with excellent properties, having the prospect of improving the performance of cementitious composites. Graphene oxide reinforced concrete (GORC) was prepared and the impact tests were performed through a φ100 mm SHPB test apparatus, to investigate the effects of impact velocity and GO content on the impact mechanical properties of concrete. The effects of GO on the pore structure and microscopic morphology of concrete were analyzed by MIP and SEM tests. Furthermore, the pore structure fractal dimension and fragment fractal dimension were calculated to quantitatively relate the microscopic pore structure to the macroscopic impact mechanical properties, and the enhancement mechanism of GO was investigated from microstructure optimization and stress dispersion mechanism. The results show that GO promotes the growth and aggregation of cement hydration products, and significantly improves the quasi-static and impact mechanical properties of concrete through filling-compacting effect and anticracking-unloading effect. When the GO content is 0.06 wt %, GO shows the best improvement effect. Compared with plain concrete (PC), the quasi-static compressive strength, dynamic compressive strength, elastic modulus, DIF, peak strain, ultimate strain and impact toughness are increased by a maximum of 29.95 %, 52.27 %, 9.79 %, 75 %, 51.54 %, 59.6 % and 86.2 % respectively. GORC has an obvious strain rate effect in the impact velocity range of 5.5 m/s-9.5 m/s, and the average particle size of specimen fragments satisfies a logarithmic relationship with the impact velocity. In addition, the pore structure fractal dimension and fragment fractal dimension satisfy a positive correlation. Larger pore structure fractal dimension indicates more defects in concrete and worse mechanical properties of it.

Structural rearrangements and fragmentation pathways induced by a low-energy electron attachment to ethyl acetate

Structural rearrangements and fragmentation pathways induced by a low-energy electron attachment to ethyl acetate

Expanding Predictive Capacities in Toxicology: Insights from Hackathon-Enhanced Data and Model Aggregation.

In the realm of predictive toxicology for small molecules, the applicability domain of QSAR models is often limited by the coverage of the chemical space in the training set. Consequently, classical models fail to provide reliable predictions for wide classes of molecules. However, the emergence of innovative data collection methods such as intensive hackathons have promise to quickly expand the available chemical space for model construction. Combined with algorithmic refinement methods, these tools can address the challenges of toxicity prediction, enhancing both the robustness and applicability of the corresponding models. This study aimed to investigate the roles of gradient boosting and strategic data aggregation in enhancing the predictivity ability of models for the toxicity of small organic molecules. We focused on evaluating the impact of incorporating fragment features and expanding the chemical space, facilitated by a comprehensive dataset procured in an open hackathon. We used gradient boosting techniques, accounting for critical features such as the structural fragments or functional groups often associated with manifestations of toxicity.

Thermally stressed state of asphalt concrete layer on a metal base

The results of a finite element study of the thermally stressed and deformed states of a fragment of a two-layer bridge structure, consisting of a bearing metal orthotropic slab with a layer of asphalt concrete applied on it, are presented. It is believed that the materials of the layers are characterized by different thermomechanical parameters, which determine the inhomogeneity of the stress and strain fields. An analogue of these phenomena can be the effect of transformation in electric thermal relays of thermal action on a bimetallic plate with different coefficients of thermal linear expansion into its mechanical displacements, which are used to actuate the switch and switches. Using the method of computer modeling, it was found that these factors lead to the concentration of stresses and strains and changes in the stress-strain state in all elements of the bridge structure end are not taken into account in the modern practice of designing and operating bridges, as well as are one of the reasons for the premature destruction of asphalt concrete pavements. To eliminate these shortcomings, on the basis of finite element algorithms, a theoretical analysis of the thermally stressed state of a metal bridge slab with an asphalt concrete pavement at various ratios of their thicknesses is carried out. It is shown that an increase in the thickness of the upper layer can lead to an increase in shear and normal tensile stresses initiated in it. Therefore, when designing bridge structures, these features should be additionally taken into account.

Environmentally safe installation for determining the fire resistance of coatings and fire resistance tests of small fragments building structures

Actuality. Taking into account fire statistics, the task of preventing the occurrence and spread of fires is urgent. It is obvious that the fire resistance of building structures, which must be taken into account at the design stage, is of the greatest importance and influence on the development and spread of fires in buildings and structures. Conducting fire experiments makes it possible to obtain the most complete information about the behavior of building structures under fire effects, however, the scale of field tests, labor-intensiveness, energy consumption and damage to the environment prompts the search and development of alternative methods that would ensure the environmental friendliness of the tests, compliance with the conditions of the experiment ( standard fire temperature regime), and at the same time would make it possible to estimate the limit of fire resistance of a building structure in reduced dimensions or to experimentally determine the fire-resistant ability (efficiency) of fire-resistant coatings. Purpose. The main goal of the article is rationale use of an installation for determining the fire-resistant capacity (efficiency) of fire-resistant coatings and fire resistance tests of small-sized fragments of building structures, taking into account the reduction of the harmful load on the environment. Main results. Research has been carried out and the design features of the installation have been substantiated, the principle of which is to heat the inner space of the chamber with the help of electric heating elements, which, unlike liquid fuel (diesel fuel, fuel oil, gas), do not harm the environment. A control unit-module of variable voltage regulation designed to regulate the heating temperature of the radiation panel in the test chamber has been developed. The design of the created test setup makes it possible to increase or decrease the temperature on the heating surface of the test sample, not only with the help of the heating temperature regulator, but also in manual mode, by moving the test sample closer or further away from the radiation panel along the guides. Conclusions. According to the results of experimental tests, it was established that the chamber of the installation warms up uniformly and according to the standardized temperature-time dependence Ts = 345lg (8t+1)+20). At the same time, the temperature regulation process using BP-10 with triac output ensures stable operation of electric heating elements up to temperatures of 1000 °C. A feature of the created installation is the possibility of additional lowering or raising of the temperature on the heating surface of the experimental sample, in case of its deviation during the experiment, by means of approaching or moving away from the sample to the heating panel. The conducted studies confirm the necessary reproducibility of experimental results.

Oxygen Electroreduction Reaction on Iron, Nitrogen-doped Nanocarbons: Structure – Reactivity Relationship

Theoretical calculations at the revPBE0-D3(PCM)/def2-TZVP level were performed to investigate the mechanism of the oxygen reduction reaction (ORR) on the FeN4-doped NCMs (graphene, single-walled (6,6)-armchair and (12,0)-zigzag carbon nanotubes) as catalysts. The effect of the support and relative orientation of FeN4 fragment in the catalyst structure on the ORR activity and stability of the differently adsorbed successive intermediates (O2*, HO2*, O*, HO*, H2O2*, H2O*) is discussed. Special attention is given to the possible poisoning effect of CO. The relative catalytic activity of the metal center and the adjacent C2 site of the carbon support are analyzed depending on the structure of the support. The metal catalytic center on the armchair nanotube and graphene supports is prone to deactivation by poisoning with CO, whereas in the zigzag nanotube supported catalyst the metal center is tolerant to CO. The four-electron mechanism of ORR is shown to be preferable over the two-electron mechanism in both acidic and alkaline media, both on the metal and C2 centers.

9-chloro-5,9-dienoic and other fatty acids from marine sponge <i>Penares</i> sp.

The fatty acids and their ethyl esters from an extract of a sponge Penares sp. (South China Sea) were fractionated by high-performance liquid chromatography and analyzed by gas chromatography-mass spectrometry using pyrrolidine, 4,4-dimethyloxazoline, dimethyl disulfide, and hydrogenated derivatives. In some cases, 1Н and 13С NMR spectroscopy was applied for the structural analysis of fatty acids. 71 С12–С28 acids, including 12 new compounds, were found. The new compounds were shown to be (5Z,9Z)-9-chloro-24-methy-5,9-pentacosadienoic, (5Z,9Z)-9-chloro-25-methyl-5,9-hexacosadienoic, (5Z,9Z)-9-chloro-24-methyl-5,9-hexacosadienoic, (5Z,9Z)-9-chloro-25-methyl-5,9-heptacosadienoic, 6-chloro-20-methyl-4-heneicosenoic, 6-chloro-19-methyl-4-heneicosenoic, 6-chloro-20-methyl-4-docosenoic, cis-17,18-methylene-tetracosanoic, 16,21-dimethyldocosanoic, 18,23-dimethyltetracosanoic, 16,18,22-trimethyltricosanoic, and 18,20,24-trimethylpentacosanoic acids. It was shown that the characteristic features of the fatty acid mixture were a high level of constituents with monomethylated chains (over 50%) and the nearly total substitution of common demospongic acids for their chloro-derivatives, previously unknown (5Z,9Z)-9-chloro-5,9-dienoic acids. The presence of analogous structural fragments in the fatty acids from Penares sp. and in some biologically active secondary metabolites from Penares sponges was discussed. The results of this work may be used for the structural, comparative and biosynthetic studies of marine lipids.

Advancing blast fragmentation simulation of RC slabs: A graph neural network approach

Accurate prediction of blast-induced fragmentation in reinforced concrete (RC) structures is pivotal for structural debris hazard assessment in an explosion event. This assessment is essential for designing effective measures for protection of people and structure in the vicinity. While conventional computational techniques are proficient, they are computationally very demanding and may not be readily adaptable in practical applications. This study proposes a novel approach, the Fragment Graph Network (FGN), a specialized variant of graph neural networks (GNNs), to simulate complex interactions between macro-level particles of RC structures subjected to close-in blast loads. The RC structure is discretised into particles, with the model predicting structural responses and fragmentation based on states of these particles. Utilizing an autoregressive prediction mechanism, our model can accurately simulate spatiotemporal responses of RC slabs against blast loads. The efficacy of the model was tested on a dataset consisting of 149 simulated cases, encompassing around 180,000 states each, covering a wide range of blasting scenarios and structural design parameters including TNT charge weight, standoff distance, slab dimension, concrete strength, and reinforcement ratio and layout. Notably, the proposed model delivered accurate predictions, achieving relative errors under 10% and R2 values exceeding 0.93 for both standard and extrapolated test scenarios as compared to the SPH simulations. Remarkably, our model dramatically outpaced traditional numerical approaches, reducing simulation times from hours to minutes on CPUs and seconds on GPUs. This pioneering effort paves the way for efficient and accurate simulations of RC blast fragmentations, offering a rapid alternative to standard numerical approaches.

Structural Survey of Antigen Recognition by Synthetic Human Antibodies.

Synthetic antibody libraries have been used extensively to isolate and optimize antibodies. To generate these libraries, the immunological diversity and the antibody framework(s) that supports it outside of the binding regions are carefully designed/chosen to ensure favorable functional and biophysical properties. In particular, minimalist, single-framework synthetic libraries pioneered by our group have yielded a vast trove of antibodies to a broad array of antigens. Here, we review their systematic and iterative development to provide insights into the design principles that make them a powerful tool for drug discovery. In addition, the ongoing accumulation of crystal structures of antigen-binding fragment (Fab)-antigen complexes generated with synthetic antibodies enables a deepening understanding of the structural determinants of antigen recognition and usage of immunoglobulin sequence diversity, which can assist in developing new strategies for antibody and library optimization. Toward this, we also survey here the structural landscape of a comprehensive and unbiased set of 50 distinct complexes derived from these libraries and compare it to a similar set of natural antibodies with the goal of better understanding how each achieves molecular recognition and whether opportunities exist for iterative improvement of synthetic libraries. From this survey, we conclude that despite the minimalist strategies used for design of these synthetic antibody libraries, the overall structural interaction landscapes are highly similar to natural repertoires. We also found, however, some key differences that can help guide the iterative design of new synthetic libraries via the introduction of positionally tailored diversity.

The importance of workplace factors and the professional identity of academic developers

ABSTRACT Academic developers enter the field of academic development (AD) from various disciplines and at different stages of their careers. They bring with them their academic experiences, home disciplinary culture and presumptions about what AD is. These circumstances inform the initial professional identity for those working in what has been described as a fragmented community. Identity impacts on an individual’s prioritisation or commitment to a particular role, which in turn impacts on work outcomes. These relationships are presently poorly understood, and so we sought to find out what factors were most influential on how AD was practiced. Nineteen developers in New Zealand and Japan were interviewed about their experiences and we found that in both countries, the often-overlooked workplace factors of role, employment, and structure were important determinants that shaped identity regardless of variations on entry to the profession. Roles we observed could be more-or-less academic or service; employment types could be permanent or temporary; and workplace structure related to the AD unit as centrally positioned in the university or embedded in one of the disciplines of higher education. These factors have received very little attention in AD identity work but are clearly important determinants of how AD is constructed and practiced. We suggest that structural fragmentation has been a stable factor over decades and unlikely to change for the foreseeable future. As such, the field is currently far away from professionalisation (with common entry requirements, practices, and standards) or shared epistemologies including where its knowledge comes from.

Comparative study on dynamic mechanical properties of additive manufacturing high strength steel and wrought high strength steel under high strain rate

Additive manufacturing high-strength steel has a unique manufacturing process and has broad application prospects in military equipment, aerospace, and other fields, but it is often threatened by dynamic loads such as explosion and high-speed impact during use, which has attracted wide attention. In this paper, the dynamic impact of additive manufacturing high-strength steel LMD-BK and wrought high-strength steel BK was carried out at strain rates of 1000 s−1–5000 s−1 by the Split-Hopkinson pressure bar (SHPB) test, respectively, and the differences in the dynamic mechanical properties of the two were investigated under the impact of different strain rates. Using scanning electron microscope (SEM) and electron backscatter diffraction (EBSD) micro-observation techniques, the microstructure morphologies of LMD-BK and BK before and after dynamic impact were characterized, and the microstructure evolution mechanism of the two was investigated. The results show that both LMD-BK and BK are strain rate sensitive, and the dynamic compressive strength increases and then decreases with the increase of strain rate, with a maximum at 2000 s−1 and a minimum at 1000 s−1. The maximum and minimum values of dynamic compressive strength for LMD-BK are 1978 MPa and 1757 MPa, respectively; for BK, the maximum and minimum values of dynamic compressive strength are 1389 MPa and 1329 MPa, respectively. The final strain of the material increases as the strain rate increases. At the same strain rate, the final strain of BK is always larger than that of LMD-BK. With the increase in strain rate, the impact work absorbed by the material increases, and at the same strain rate, LMD-BK can absorb more impact work than BK. Microscopic observations show that after dynamic impact, LMD-BK undergoes fragmentation of the columnar structure and compression of the cellular structure to form a deformation localization zone. These results are of great significance for the study of dynamic mechanical properties and microstructure evolution mechanism of high-strength steel made by additive manufacturing under extreme environments such as explosion and high-speed impact.

Intracellular rearrangements of the rat contractile myocardial apparatus during prenatal ontogenesis after alcohol influence

Background. Information on the formation of the contractile apparatus of the heart and the distribution of myofibrils in cardiomyocytes under conditions of intrauterine intoxication with ethanol remain a subject of considerable debate. The aim of the study was to determine changes in the ultrastructure of the contractile apparatus of rat ventricular cardiomyocytes during prenatal development in conditions of intrauterine alcohol intoxication. Methods. The object of the research was the hearts of rat posterity at different times from birth to adulthood in the model of chronic alcohol intoxication of the maternal organism. Quantitative parameters of cardiomyocyte myofibrils in different zones of the ventricular myocardium were determined using transmission electron microscopy. Results. In newborn rats, after exposure to ethanol, the values of the parameters in the subendocardial zone were statistically significantly increased in the left ventricle by 101.0% and in the right ventricle by 42.0%, compared to the indicators of the previous day of development. Indicators in the intramural and subepicardial zones were not significantly different from the corresponding values on the 20th day of prenatal ontogenesis. The difference between the parameters of different parts of the interventricular septum was statistically significant and amounted to 45.9% in the left ventricular part and 20.2% in the right ventricular part. The values of the parameter in the intramural zone after ethanol exposure decreased by 35.5% (p>0.05) in the left ventricle and by 36.0% (p<0.05) in the right ventricle compared to the norm. Conclusion. Chronic alcohol intoxication in prenatal cardiogenesis damages the contractile apparatus of ventricular cardiomyocytes due to disorganization of the structure of sarcomeres, fragmentation and disorientation of myofibrils, significant inhibition of sarcomere genesis, and a decrease in the content of myofibrils, which is associated with destruction of mitochondria. The severity of changes in these structures depends on the zone and period of development of the embryo. The most significant changes are due to the direct toxic effect of ethanol and occur in the early stages of cardiogenesis.

Infrastructure digital twin technology: A new paradigm for future construction industry

The construction industry has traditionally been slow to adopt digital technology, resulting in inefficient workflows, frequent cost overruns, and delays. Moreover, its fragmented structure, inherent to market dynamics, exacerbates these challenges. Embracing digitalization and transitioning to Industry 4.0 can substantially enhance efficiency and productivity in construction through increased innovation and improved collaboration, ultimately reducing information gaps and data discrepancies. This study aims to assess the potential integration of digital twin technology across various construction stages, spanning from initial design to project delivery. Existing literature emphasizes the transformative power of digital twin technology in advancing building innovation and environmental sustainability. These virtual replicas are crucial in optimizing industrial manufacturing by harmonizing production processes and societal interactions. A focused examination of digital twin technology applications in construction highlights its ability to streamline coordination and facilitate data sharing among stakeholders. Property owners increasingly recognise the value of digital twin technology in local contexts, driving the digitization of design and collaboration methods in construction. Integrating digital twin technology right from a project's inception and extending it across design phases optimizes project delivery, enhances asset quality, and contributes to societal sustainability. As the nexus between digitalization and sustainability goals strengthens, the construction industry stands at the cusp of a significant transformative journey.

Antibacterial Activity of Various Morphologies of Films Based on Guanidine Derivatives of Pillar[5]arene: Influence of the Nature of One Substitute on Self-assembly.

The progress of the pillar[5]arene chemistry allowed us to set out a new concept on application of the supramolecular assemblies to create antimicrobial films with variable surface morphologies and biological activities. Antibacterial films were derived from the substituted pillar[5]arenes containing nine pharmacophoric guanidine fragments and one thioalkyl substituent. Changing the only thioalkyl fragment in the macrocycle structure made it possible to control the biological activity of the resulting antibacterial coating. Pretreatment of the surface with aqueous solution of the amphiphilic pillar[5]arenes reduced the biofilm thickness by 56 ± 10% of Gram-positive Staphylococcus aureus in the case of the pillar[5]arene containing a thiooctyl fragment and by 52 ± 7% for the biofilm of Gram-negative Klebsiella pneumoniae in the case of pillar[5]arene containing a thiooctadecyl fragment. Meanwhile, the cytotoxicity of the synthesized macrocycles was examined at a concentration of 50 μg/mL, which was significantly lower than that of bis-guanidine-based antimicrobial preparations.