bluuebunny/crossref_metadata_2025 huggingface dataset:
RET 634 germline/gonadal mosaicism generating a second pathogenic amino acid change in multiple endocrine neoplasia type 2A
Authors: Valente Flávia O. F. , Camacho Cléber P. , Lindsey Susan C. , Yang Ji H. , Kunii Ilda S. , Santos Roberto B. , Kizys Marina M. L. , Cerutti Janete M. , Dias‐da‐Silva Magnus R. , Maciel Rui M. B.
Published: February 2024

Genetic testing for germline RET pathogenic variants, which cause the Multiple Endocrine Neoplasia Type 2 (MEN2) syndrome, has become crucial in managing patients with medullary thyroid carcinoma (MTC). Classically, RET heterozygous missense pathogenic variants are transmitted in a Mendelian autosomal dominant pattern, of which germline/gonadal mosaicism has never been reported. We report the novel occurrence of a MEN2A patient's family in which the siblings inherited three different RET 634 genotypes: wild type (p.Cys634), p.Cys634Gly or p.Cys634Arg heterozygous pathogenic variants. We hypothesized that germline/gonadal mosaicism, derived from an inherited + early somatic mutation in the mother or a double de novo mutation during maternal embryogenesis, led to this rare event in the RET gene. Exome analysis of the proband's deceased mother's paraffin‐embedded thyroid tissue confirmed the three nucleotides in the same 634 codon position. For the first time, we describe germline/gonadal mosaicism in RET, generating a second pathogenic amino acid change in the same codon causing MEN2A. Our finding shows that RET parental mosaicism, confirmed by somatic exome sequencing, might explain discrepant genotype cases in siblings with inherited cancers.
Fe, N‐Inducing Interfacial Electron Redistribution in NiCo Spinel on Biomass‐Derived Carbon for Bi‐functional Oxygen Conversion
Authors: Liu Yanyan , Zhou Limin , Liu Shuling , Li Shuqi , Zhou Jingjing , Li Xin , Chen Xiangmeng , Sun Kang , Li Baojun , Jiang Jianchun , Pang Huan
Published: February 2024

Herein, an interfacial electron redistribution is proposed to boost the activity of carbon‐supported spinel NiCo2O4 catalyst toward oxygen conversion via Fe, N‐doping strategy. Fe‐doping into octahedron induces a redistribution of electrons between Co and Ni atoms on NiCo1.8Fe0.2O4@N‐carbon. The increased electron density of Co promotes the coordination of water to Co sites and further dissociation. The generation of proton from water improves the overall activity for the oxygen reduction reaction (ORR). The increased electron density of Ni facilitates the generation of oxygen vacancies. The Ni−VO−Fe structure accelerates the deprotonation of *OOH to improve the activity toward oxygen evolution reaction (OER). N‐doping modulates the electron density of carbon to form active sites for the adsorption and protonation of oxygen species. Fir wood‐derived carbon endows catalyst with an integral structure to enable outstanding electrocatalytic performance. The NiCo1.8Fe0.2O4@N‐carbon express high half‐wave potential up to 0.86 V in ORR and low overpotential of 270 mV at 10 mA cm−2 in OER. The zinc‐air batteries (ZABs) assembled with the as‐prepared catalyst achieve long‐term cycle stability (over 2000 cycles) with peak power density (180 mWcm−2). Fe, N‐doping strategy drives the catalysis of biomass‐derived carbon‐based catalysts to the highest level for the oxygen conversion in ZABs.
Reaktivität von Superbasischen Carbanionen erzeugt über Reduktiven Radikal‐Polaren Übergang im Kontext der Photoredoxkatalyse
Authors: Grotjahn Sascha , Graf Christina , Zelenka Jan , Pattanaik Aryaman , Müller Lea , Kutta Roger Jan , Rehbein Julia , Roithová Jana , Gschwind Ruth M. , Nuernberger Patrick , König Burkhard
Published: February 2024

Photokatalytische Reaktionen, die einen reduktiven radikal‐polaren Übergang (RRPCO) beinhalten, erzeugen Intermediate mit carbanionischer Reaktivität. Viele dieser postulierten Intermediate entsprechen hochreaktiven metallorganischen Verbindungen. Die Bedingungen für ihre Bildung werden im Allgemeinen jedoch von ihren isolierten metallorganischen Analoga nicht toleriert und häufig wird eine andere Reaktivität beobachtet. Unsere Untersuchungen zu ihrer Natur und Reaktivität unter den üblichen photokatalytischen Bedingungen zeigen auf, dass diese Intermediate in der Tat als freie, superbasische Carbanionen beschrieben werden können, die in der Lage sind, gängige polare Lösungsmittel wie Acetonitril und Dimethylsulfoxid zu deprotonieren, die normalerweise als inert gelten. Ihre Basizität, nicht nur gegenüber Lösungsmitteln, sondern auch gegenüber Elektrophilen wie Aldehyden, Ketonen und Estern, ist vergleichbar mit der Reaktivität von isolierten Carbanionen in der Gasphase. Zuvor erfolglose Reaktionen, von denen man annahm, dass sie aus mangelnder Reaktivität resultieren, lassen sich durch ihre hohe Reaktivität gegenüber dem Lösungsmittel und schwach aciden Protonen der Reaktionspartner erklären. Dies liefert eine intuitive Erklärung für das Verhalten von photokatalytisch erzeugten Carbanionen, die es ermöglicht, Reaktionsmechanismen zu verifizieren, bei denen ein RRPCO‐Schritt vermutet wird, und erlaubt eine Abschätzung des synthetischen Anwendungsbereiches.
The Ferroxidase Centre of Escherichia coli Bacterioferritin Plays a Key Role in the Reductive Mobilisation of the Mineral Iron Core
Authors: Bradley Justin M. , Bugg Zinnia , Sackey Aaren , Andrews Simon C. , Wilson Michael T. , Svistunenko Dimitri A. , Moore Geoffrey R. , Le Brun Nick E.
Published: February 2024

Ferritins are multimeric cage‐forming proteins that play a crucial role in cellular iron homeostasis. All H‐chain‐type ferritins harbour a diiron site, the ferroxidase centre, at the centre of a 4 α‐helical bundle, but bacterioferritins are unique in also binding 12 hemes per 24 meric assembly. The ferroxidase centre is known to be required for the rapid oxidation of Fe2+ during deposition of an immobilised ferric mineral core within the protein's hollow interior. In contrast, the heme of bacterioferritin is required for the efficient reduction of the mineral core during iron release, but has little effect on the rate of either oxidation or mineralisation of iron. Thus, the current view is that these two cofactors function in iron uptake and release, respectively, with no functional overlap. However, rapid electron transfer between the heme and ferroxidase centre of bacterioferritin from Escherichia coli was recently demonstrated, suggesting that the two cofactors may be functionally connected. Here we report absorbance and (magnetic) circular dichroism spectroscopies, together with in vitro assays of iron‐release kinetics, which demonstrate that the ferroxidase centre plays an important role in the reductive mobilisation of the bacterioferritin mineral core, which is dependent on the heme‐ferroxidase centre electron transfer pathway.
A Semi‐Automated, High‐Throughput Approach for the Synthesis and Identification of Highly Photo‐Cytotoxic Iridium Complexes
Authors: Kench Timothy , Rahardjo Arielle , Terrones Gianmarco G. , Bellamkonda Adinarayana , Maher Thomas E. , Storch Marko , Kulik Heather J. , Vilar Ramon
Published: February 2024

The discovery of new compounds with pharmacological properties is usually a lengthy, laborious and expensive process. Thus, there is increasing interest in developing workflows that allow for the rapid synthesis and evaluation of libraries of compounds with the aim of identifying leads for further drug development. Herein, we apply combinatorial synthesis to build a library of 90 iridium(III) complexes (81 of which are new) over two synthesise‐and‐test cycles, with the aim of identifying potential agents for photodynamic therapy. We demonstrate the power of this approach by identifying highly active complexes that are well‐tolerated in the dark but display very low nM phototoxicity against cancer cells. To build a detailed structure–activity relationship for this class of compounds we have used density functional theory (DFT) calculations to determine some key electronic parameters and study correlations with the experimental data. Finally, we present an optimised semi‐automated synthesise‐and‐test protocol to obtain multiplex data within 72 hours.
Synthesis, characterization, and photocatalytic activity for water remediation and hydrogen evolution of Zn(II) and Ni(II) bis(thiosemicarbazone) complexes
Authors: Burón Rodrigo , Jiménez‐Gómez Daniel , Calatayud David G. , Iglesias‐Juez Ana , Fresno Fernando , Mendiola M. Antonia , López‐Torres Elena
Published: February 2024

The extensive industrial use of organic dyes causes large amounts of these substances to arrive at water sources, so nowadays, organic compound removal from fresh water is a major concern. The use of photocatalysts is an interesting approach to solving this problem, with coordination compounds playing an outstanding role. We report the selective synthesis and characterization of three new dissymmetric bis(thiosemicarbazone) ligands and their nickel(II) and zinc(II) complexes, which have been fully characterized by several techniques. The photocatalytic activity of the six complexes for methyl orange degradation was also evaluated. All the complexes can degrade this organic dye, although the photoefficiency of the nickel compounds is, in general, higher than for the zinc ones, as the degradation is faster and they do not reach a plateau. Density functional theory calculations show a clear dependence of the highest occupied molecular orbital (HOMO)–lowest unoccupied molecular orbital (LUMO) gap, as well as with the relative energies of these orbitals. On the other hand, the need for green fuels that do not produce the greenhouse effect is one of the major goals of modern life, and molecular hydrogen is one of the most promising ones. Considering the proven potential of bis(thiosemicarbazone) complexes to electrocatalyze H2 evolution recently reported in the literature, we also made some preliminary tests to investigate the potential of the nickel complexes to act as photocatalysts for water splitting. The results indicate that two of the complexes produce H2 in the conditions tested, so they could be used in the development of efficient photocatalytic systems for hydrogen evolution.
Study on mechanical, thermal and shape memory properties of polycarbonate/thermoplastic polyurethane blends
Authors: Tyagi Mukti , Rawat Rajkumar Singh , Tyagi Vinay Kumar , Talwar Meenu , Kumar Manmohan , Das Mukul , Roy Prasun
Published: February 2024

The objective of the study is preparation of shape memory blend of polycarbonate (PC) and thermoplastic polyurethane (TPU). Polycarbonate is blended with three types of TPUs and subsequently mechanical, thermal, morphological, and shape memory properties of the PC/TPU blends are studied. When TPU content in the blend is higher than 40% (by weight), the glass transition temperature related to PC is not shown in the differential scanning calorimetry thermogram, indicating loss of PC properties. The 60/40 optimized blend of PC/TPUs exhibits maximum increment of about 1100% in elongation and 43% decrement in tensile strength. The shape recovery of the optimized blend obtained by addition of 40% (by weight) of TPUs in PC polymer is found to be 65% and shape fixity is 97%. These results suggest that the blend of PC/TPU may be utilized for various applications where shape memory property is required including strategic applications.
Wettability alteration of oil‐wet carbonate rocks by chitosan derivatives for application in enhanced oil recovery II: High‐temperature and high‐pressure conditions—Core flooding tests
Authors: dos Santos Francisco Agatha Densy , Maia Kelly Cristina Bastos , de Almeida Cavadas Leandro , Eler Felipe Moreira , Grasseschi Daniel , Couto Paulo , Nascimento Regina Sandra Veiga
Published: February 2024

Biopolymers, serving as Enhanced Oil Recovery (EOR) agents, are posing challenges and opportunities within the oil industry, particularly in demanding operational conditions. The assessment of trimethyl chitosan (TMC) and its hydrophobized derivative with myristoyl chloride (TMC‐C14) becomes crucial in these rigorous scenarios, presenting a significant challenge for polymer flooding. The study subjected TMC and TMC‐C14 to comprehensive evaluations as EOR agents, employing contact angle measurements, interfacial tension tests using the Drop Shape Analyzer (DSA), and core flood tests under conditions of 60°C, 1000 psi, and elevated salinity. Relative permeabilities were deduced from the results, while spontaneous imbibition tests provided insights into rock wettability. Amott cell tests underscored that both TMC and TMC‐C14 induced accelerated spontaneous oil production within a span of 30 days. Notably, TMC‐C14 exhibited superior interfacial activity compared to TMC, attributed to its hydrophobic segments. The impact on rock wettability was distinct: TMC shifted it towards water‐wet, while TMC‐C14 induced a neutral‐wet condition. This transformation was corroborated by contact angle measurements, imbibition tests, and relative permeability curves. Capillary forces, computed from DSA data and spontaneous imbibition tests, further validated the wettability‐altering tendencies of the chitosan derivatives on the rock. In core flooding tests and relative permeability curves, TMC demonstrated a notable improvement in the recovery factor (RF) compared to seawater. Specifically, RFTMC achieved 69%, surpassing RFbrine at 49%, affirming that the primary mechanism of action for chitosan derivatives lies in their ability to modify rock wettability. This study shows the potential of TMC and TMC‐C14 as effective EOR agents, shedding light on their interfacial activities, impact on rock wettability, and enhanced recovery factors in challenging operational conditions.
Chemical composition and biological activities of Cucurbita okeechobeensis extracts from its aerial parts, seeds, and fruit shells
Authors: Llorent‐Martínez Eulogio J. , Ruiz‐Medina Antonio , Terzic Milena , Sinan Kouadio Ibrahime , Koyuncu Ismail , Egi Kadir , Nilofar Nilofar , Zengin Gokhan
Published: February 2024

The Cucurbita genus has been widely used in traditional medicinal systems across different countries. In this study, we aimed to investigate the chemical composition, antioxidant properties, enzyme inhibitory, and cytotoxic effects of methanol and aqueous extracts obtained from the aerial parts, seeds, and fruit shells of Cucurbita okeechobeensis. Antioxidant properties were assessed using various chemical methods, including radical quenching (DPPH and ABTS), reducing power (CUPRAC and FRAP), metal chelation, and phosphomolybdenum assays. The extracts' enzyme inhibitory effects were tested against cholinesterase, amylase, glucosidase, and tyrosinase, whereas different cancer cell lines were used for the cytotoxicity study. The chemical composition, evaluated by HPLC‐ESI‐MSn, showed that the most abundant compounds were flavonoids (mainly quercetin glycosides) followed by phenolic acids (mostly caffeic acid derivatives). The aerial parts displayed stronger antioxidant ability than the seed and fruit shells, in agreement with the highest content in phytochemicals. In addition, the methanol extracts presented the highest bioactivity and content in phytochemicals; among them, the extract of the aerial part exhibited significant cytotoxic effects on cancer cell lines and induced apoptosis. Overall, our results suggest that C. okeechobeensis is a valuable source of bioactive compounds for the pharmaceutical and nutraceutical industries.
Anodization as a scalable nanofabrication method to engineer mechanobactericidal nanostructures on complex geometries
Authors: Roy Anindo , Reddy Kolipyak Sravan , Chatterjee Kaushik
Published: February 2024

Bacterial contamination of implant surfaces is one of the primary causes of their failure, and this threat has been further exacerbated due to the emergence of drug‐resistant bacteria. Nanostructured mechanobactericidal surfaces that neutralize bacteria via biophysical forces instead of traditional biochemical routes have emerged as a potential remedy against this issue. Here, we report on the bactericidal activity of titania nanotubes (TNTs) prepared by anodization, a well‐established and scalable method. We investigate the differences in bacterial behavior between three different topographies and demonstrate the applicability of this technique on complex three‐dimensional (3D) geometries. It was found that the metabolic activity of bacteria on such surfaces was lower, indicative of disturbed intracellular processes. The differences in deformations of the cell wall of Gram‐negative and positive bacteria were investigated from electron micrographs Finally, nanoindentation experiments show that the nanotubular topography was durable enough against forces typically experienced in daily life and had minimal deformation under forces exerted by bacteria. Our observations highlight the potential of the anodization technique for fabricating mechanobactericidal surfaces for implants, devices, surgical instruments, and other surfaces in a healthcare setting in a cheap, scalable way.
On the Existence of Pnictogen Bonding Interactions in As(III) S‐Adenosylmethionine Methyltransferase Enzymes
Authors: Gomila Rosa M. , Frontera Antonio
Published: February 2024

As(III) S‐adenosylmethionine methyltransferases, pivotal enzymes in arsenic metabolism, facilitate the methylation of arsenic up to three times. This process predominantly yields trivalent mono‐ and dimethylarsenite, with trimethylarsine forming in smaller amounts. While this enzyme acts as a detoxifier in microbial systems by altering As(III), in humans, it paradoxically generates more toxic and potentially carcinogenic methylated arsenic species. The strong affinity of As(III) for cysteine residues, forming As(III)‐thiolate bonds, is exploited in medical treatments, notably in arsenic trioxide (Trisenox®), an FDA‐approved drug for leukemia. The effectiveness of this drug is partly due to its interaction with cysteine residues, leading to the breakdown of key oncogenic fusion proteins. In this study, we extend the understanding of As(III)′s binding mechanisms, showing that, in addition to As(III)−S covalent bonds, noncovalent O⋅⋅⋅As pnictogen bonding plays a vital role. This interaction significantly contributes to the structural stability of the As(III) complexes. Our crystallographic analysis using the PDB database of As(III) S‐adenosylmethionine methyltransferases, augmented by comprehensive theoretical studies including molecular electrostatic potential (MEP), quantum theory of atoms in molecules (QTAIM), and natural bond orbital (NBO) analysis, emphasizes the critical role of pnictogen bonding in these systems. We also undertake a detailed evaluation of the energy characteristics of these pnictogen bonds using various theoretical models. To our knowledge, this is the first time pnictogen bonds in As(III) derivatives have been reported in biological systems, marking a significant advancement in our understanding of arsenic‘s molecular interactions.
Nano Metal–Organic Frameworks as Advanced Electrode Materials in Electrochemical Energy Storage
Authors: Wu Xiaohui , Fan Ziheng , Hu Jinliang , Yan Yan , Pang Huan
Published: February 2024

Nano metal–organic frameworks as an attractive new class of porous materials, are synthesized via metal ions and organic ligands. With their desirable properties of abundant pores, high specific surface areas, fully exposed active sites and controllable structures, nano MOFs are acknowledged to be one of the most vital materials in electrochemical energy storages. However, in their practical applications, nano MOFs are still confronted with various difficulties and challenges because of their low conductivity, poor stability, and other disadvantages. The selection and development of MOF composites, MOF–derived materials and modified MOFs might be beneficial to use as better electrode materials to greatly improve the electrochemical properties of energy storage devices. This paper mainly focuses on the recent developments of nano MOFs as prospective materials in electrochemical energy storage applications, including lithium–ion batteries (LIB), lithium–sulfur batteries (LSB), zinc–ion batteries (ZIB), and supercapacitors (SCs). Finally, the challenges faced by these kinds of energy storage devices are proposed, along with the current directions and prospect.
Green synthesis of tellurium‐doped SnO2 nanoparticles with sulfurized g‐C3N4: Insights into methylene blue photodegradation and antibacterial capability
Authors: Umar Misbah , Ajaz Humayun , Javed Mohsin , Mansoor Sana , Iqbal Shahid , Mahmood Sajid , Rauf Abdul , Aroosh Komal , Bahadur Ali , Alshalwi Matar
Published: February 2024

The construction of SnO2 nanoparticles (NPs), specifically Te‐doped SnO2 NPs, using a simple and economical co‐precipitation technique has been thoroughly described in this work. NH3 served as the reducing agent in this procedure, whilst polyethylene glycol served as the capping agent. The primary goals of our work were to investigate the physicochemical properties of the synthesized SnO2 NPs and assess their potential use as antibacterial agents and photocatalysts. Scanning electron microscopy–energy dispersive X‐ray, ultraviolet light, Fourier transform infrared spectroscopy, X‐ray diffraction (XRD), and other analytical techniques were used to thoroughly analyze the NPs. Based on the full width at half maximum of the most noticeable peaks in the XRD spectrum, the Debye–Scherrer equation was used to calculate the crystallite sizes, which indicated the presence of a single tetragonal SnO2 phase. Particularly noteworthy was the exceptional photocatalytic activity of graphene‐assisted Te‐doped SnO2 NPs, achieving an impressive decomposition efficiency of up to 98% in the photo‐oxidation of methylene blue. Furthermore, our investigation delved into the antibacterial attributes of the synthesized SnO2 NPs against Escherichia coli and Staphylococcus aureus, demonstrating inhibitory effects on both bacteria strains. This suggests potential applications for these NPs in various environmental and medical contexts.
Intermediate product control in cascade reaction for one‐pot production of ε‐caprolactone by Escherichia coli
Authors: Chen Hefeng , Liu Ran , Cai Shengliang , Zhang Yingjiao , Zhu Chaoyi , Yu Hao , Li Shuang
Published: February 2024

ε‐Caprolactone is an important non‐toxic compound for polymer synthesis like polycaprolactone which has been widely used in drug delivery and degradable plastics. To meet the demand for a green economy, a bi‐enzymatic cascade, consisting of an alcohol dehydrogenase (ADH) and a cyclohexanone monooxygenase (CHMO), was designed and introduced into Escherichia coli to synthesize ε‐caprolactone from cyclohexanol with a self‐sufficient NADPH‐cofactor regeneration system. To further improve the catalytic efficiency, a carbonyl group‐dependent colorimetric method using inexpensive 2,4‐dinitrophenylhydrazine (DNPH) was developed for assay of cyclohexanone, an intermediate production of cascade reaction. It can be used to screen mutant strains with high catalytic efficiency from high‐throughput library by detecting the absorbance value in microtiter plates (MTP) instead of gas chromatography (GC) analysis. Moreover, an RBS combinatorial library was constructed for balancing the expression of ADH and CHMO from two independent transcriptional units. After the high‐throughput screening based on intermediate product control, an optimal variant with higher substrate tolerance and long‐term stability was obtained from RBS combinatorial library. Through a fed‐batch process, ε‐caprolactone production reached 148.2 mM after 70 h of reaction under the optimized conditions, which was the highest yield achieved to date.
Lung‐specific exosomes for doxorubicin delivery in lung adenocarcinoma therapy
Authors: Yu Fengqiang , Chen Yanxun , Yi Weiqiang , Guan Maohao , Lin Nanlong , Zhuo Yi , Lin Jianbo , Lai Fancai
Published: February 2024

Doxorubicin (DOX) could be utilized to treat lung adenocarcinoma (LUAD), while dose‐limiting cardiotoxicity limits its clinical utilization. MDA‐MB‐231 cell‐derived exosomes show lung‐specific organotropism features. In this study, we aimed to explore the potential of MDA‐MB‐231 cell‐derived exosomes in DOX specific delivery to the lung. MDA‐MB‐231 cell‐derived exosomes were coincubated with to construct for the doxorubicin delivery system (D‐EXO). Exosomes labeled with fluorescein isothiocyanate were incubated with A549 cells or 293T cells, and the engulf and the mean intensity of the fluorescence were detected with immunofluorescence and flow cytometry assay. Cell viability was detected with cell counting kit‐8 (CCK‐8), and cell migration was determined by scratch test. The protein expression was detected by Western blot assay. A549 cell line‐derived xenograft mouse model was constructed to examine the treatment effect of D‐EXO. MDA‐MB‐231 cell‐derived exosomes could be specially taken up by A549 cells with diminished cell viability but not engulfed by 293T cells. D‐EXO inhibited A549 cell migration, and upregulated the protein expression of caspase 3 and cleaved caspase 3 expression, while did not show any inhibition on 293T cells. In vivo orthotopic xenotransplantation model indicated that D‐EXO inhibited tumor growth characterized by diminished tumor weight and improved survival rate. No significant change in body weight was observed after the D‐EXO treatment. In conclusion, D‐EXO proposed in this study could be utilized to treat LUAD with lung‐specific delivery effects to improve the survival rate.
Duplication of a chromosome 2 segment in production CHO cell lines correlates with age‐related growth improvement
Authors: Wei Wei , Zielewicz Laura , Zhang Lin
Published: February 2024

Monitoring the stability of recombinant Chinese Hamster Ovary (CHO) cell lines is essential to ensure the selection of production cell lines suitable for biomanufacturing. It has been frequently observed that recombinant CHO cell lines develop phenotypic changes upon aging, such as accelerated cell growth in late generation cultures. However, the mechanism responsible for age‐correlated changes is poorly understood. In this study, we investigated the molecular mechanisms underlying the age‐correlated cell growth improvement in Pfizer's platform fed‐batch production process, by examining multiple cell lines derived from different CHO expression systems, expressing a variety of monoclonal antibodies (mAbs). Comprehensive whole‐genome resequencing analysis revealed duplication of a continuous 50.2 Mbp segment in chromosome 2 (Chr2) specific to clones that showed age‐correlated growth change as compared to clones that did not exhibit age‐correlated growth change. Moreover, such age‐ and growth‐related Chr2 duplication was independent of the presence or type of recombinant monoclonal antibody expression. When we compared transcriptome profiles from low‐growth and high‐growth cell lines, we found that >95% of the genes overexpressed in high‐growth cell lines were in the duplicated Chr2 segment. To the best of our knowledge, this is the first report of large genomic duplication, specific to Chr2, being associated with age‐correlated growth change. Investigation of the cause‐and‐effect relationship between the genes identified in the duplicated regions and age‐correlated growth change is underway. We are confident that this effort will lead to improved cell line screening and targeted rational cell line engineering efforts to develop cell lines with improved stability performance.
High throughput generating stable spheroids with tip‐refill wafer
Authors: Yang Xiaoyan , Pan Rong , Ning Ke , Xie Yuanyuan , Chen Feng , Sun Wei , Yu Ling
Published: February 2024

Three‐dimensional (3D) cell cultures have garnered significant attention in biomedical research due to their ability to mimic the in vivo cellular environment more accurately. The formation of 3D cell spheroids using hanging drops has emerged as a cost‐effective and crucial method for generating uniformly‐sized spheroids. This study aimed to validate the potential of a tip‐refill wafer (TrW), a disposable laboratory item used to hold pipette tips, in facilitating 3D cell culture. The TrW allows for easy generation of hanging drops by pipetting the solution into the holes of the wafer. The mechanical stability of the hanging drops is ensured by the surface wettability and thickness of the TrW. Hanging drops containing 60‐µL of solution remained securely attached to the TrW even when subjected to orbital shaking at 210 rpm. The exceptional resistance to mechanical shaking enabled the use of inertial focusing to facilitate spheroid formation. This was demonstrated through live/dead cell staining, quantitative polymerase chain reaction (qPCR) analysis, and cytoskeleton staining, which revealed that horizontal orbiting at 60 rpm for 15 min promoted cell aggregation and ultimately led to the formation of 3D spheroids. The spheroid harvest rate is 96.1% ± 3.5% across three TrWs, each containing 60 hanging drops. In addition to generating mono‐culture 3D spheroids, the TrW‐based hanging drop platform also enables the formation of multicellular spheroids, and on‐demand pairing and fusion of spheroids. The TrW is a disposable item that does not require any fabrication or surface modification procedures, further enhancing its application potential in conventional biological laboratories.
Encapsulation of pristine and silica‐coated human adipose‐derived mesenchymal stem cells in gelatin colloidal hydrogels for tissue engineering and bioprinting applications
Authors: Maciel Marta M. , Hassani Besheli Negar , Correia Tiago R. , Mano João F. , Leeuwenburgh Sander C. G.
Published: February 2024

Colloidal gels assembled from gelatin nanoparticles (GNPs) as particulate building blocks show strong promise to solve challenges in cell delivery and biofabrication, such as low cell survival and limited spatial retention. These gels offer evident advantages to facilitate cell encapsulation, but research on this topic is still limited, which hampers our understanding of the relationship between the physicochemical and biological properties of cell‐laden colloidal gels. Human adipose‐derived mesenchymal stem cells were successfully encapsulated in gelatin colloidal gels and evaluated their mechanical and biological performance over 7 days. The cells dispersed well within the gels without compromising gel cohesiveness, remained viable, and spread throughout the gels. Cells partially coated with silica were introduced into these gels, which increased their storage moduli and decreased their self‐healing capacity after 7 days. This finding demonstrates the ability to modulate gel stiffness by incorporating cells partially coated with silica, without altering the solid content or introducing additional particles. Our work presents an efficient method for cell encapsulation while preserving gel integrity, expanding the applicability of colloidal hydrogels for tissue engineering and bioprinting. Overall, our study contributes to the design of improved cell delivery systems and biofabrication techniques.
Recent advances in applying omic technologies for studying acetic acid bacteria in industrial vinegar production: A comprehensive review
Authors: Román‐Camacho Juan J. , Mauricio Juan C. , Santos‐Dueñas Inés María , García‐Martínez Teresa , García‐García Isidoro
Published: February 2024

Vinegar and related bioproducts containing acetic acid as the main component are among the most appreciated fermented foodstuffs in numerous European and Asian countries because of their exceptional organoleptic and bio‐healthy properties. Regarding the acetification process and obtaining of final products, there is still a lack of knowledge on fundamental aspects, especially those related to the study of biodiversity and metabolism of the present microbiota. In this context, omic technologies currently allow for the massive analysis of macromolecules and metabolites for the identification and characterization of these microorganisms working in their natural media without the need for isolation. This review approaches comprehensive research on the application of omic tools for the identification of vinegar microbiota, mainly acetic acid bacteria, with subsequent emphasis on the study of the microbial diversity, behavior, and key molecular strategies used by the predominant groups throughout acetification. The current omics tools are enabling both the finding of new vinegar microbiota members and exploring underlying strategies during the elaboration process. The species Komagataeibacter europaeus may be a model organism for present and future research in this industry; moreover, the development of integrated meta‐omic analysis may facilitate the achievement of numerous of the proposed milestones. This work might provide useful guidance for the vinegar industry establishing the first steps towards the improvement of the acetification conditions and the development of new products with sensory and bio‐healthy profiles adapted to the agri‐food market.
Hydrodynamic studies of innovative membrane reactor for enzymatic hydrolysis of lignocellulosic waste
Authors: Dąbkowska‐Susfał Katarzyna , Lipińska Joanna , Sobieszuk Paweł , Kołtuniewicz Andrzej B.
Published: February 2024

This paper presents the study concerning the impact of the basic operational parameters on the performance of an innovative microfiltration membrane reactor applied for enzymatic hydrolysis of lignocellulosic biomass. The concept and basic hydrodynamics of the reactor with tubular ceramic membranes and a propeller agitator were shown. Besides, the efficiency of enzymatic hydrolysis of corn straw was studied to check reactor functionality. It has been proven that the proposed reactor construction can improve the microfiltration of lignocellulosic suspension by reducing the cake layer on the membrane surface. Increasing the rotational speed of the propeller agitator also improved the filtration efficiency. The permeate flux during the microfiltration experiments was lower for smaller lignocellulose biomass fraction (D < 425 μm) when compared to the less fragmented corn straw (425 < D < 900 μm). For larger solid fractions, a stirring speed increase enhanced the separation efficiency regardless of the differences in biomass concentration. In contrast, this trend for the finer biomass fraction was only noticeable for the highest used biomass concentration (C = 2.0%). Considering the enzymatic hydrolysis of corn straw, membrane separation of reaction products positively influenced the process yield, and the results depended on the applied operational parameters.
A sustainable strategy for biosynthesis of Rebaudioside D using a novel glycosyltransferase of Solanum tuberosum
Authors: Ma Siyuan , Ma Yuanyuan
Published: February 2024

Bioconversion of Rebaudioside D faces high‐cost obstacles. Herein, a novel glycosyltransferase StUGT converting Rebaudioside A to Rebaudioside D was screened and characterized, which exhibits stronger affinity and substrate specificity for Rebaudioside A than previously reported enzymes. A whole‐cell catalytic system was thus developed using the StUGT strain. The production of Rebaudioside D was enhanced significantly by enhancing cell permeability, and the maximum production of 6.12 g/L and the highest yield of 98.08% by cell catalyst was obtained by statistical‐based optimization. A new cascade process utilizing this recombinant strain and E. coli expressing sucrose synthase was further established to reduce cost through replacing expensive UDPG with sucrose. A StUGT‐GsSUS1 system exhibited high catalytic capability, and 5.27 g L−1 Rebaudioside D was achieved finally without UDPG addition by systematic optimization. This is the best performance reported in cell‐cascaded biosynthesis, which paves a new cost‐effective strategy for sustainable synthesis of scarce premium sweeteners from biomass.
Liamocins overproduction via the two‐pH stage fermentation and anti‐Aspergillus flavus activity of Massoia lactone
Authors: Wang Peng , Zhang Mei , Zhao Shou‐Feng , Zhang Zhao‐Rui , Liu Guang‐Lei , Chi Zhe , Chi Zhen‐Ming
Published: February 2024

Aureobasidium melanogenum was found to be grown the best at the constant pH 7.0 and to produce the highest amount of liamocins at the constant pH 3.0. Therefore, the wild type strain A. melanogenum 9‐1 and the engineered strain V33 constructed in the laboratory were grown at the constant pH 7.0 for 48 h, then, they were continued to be cultivated at the constant pH 3.0. Under such conditions, A. melanogenum 9‐1 produced 36.51 ± 0.55 g L−1 of liamocin and its cell mass was 27.43 ± 0.63 and 6.00 ± 0.11 g L−1 of glucose was left in the finished medium within 168 h while the engineered strain V33 secreted 70.86 ± 2.04 g L−1 of liamocin, its cell mass was 31.63 ± 0.74 g L−1, 0.16 ± 0.01 g L−1 of glucose was maintained in the finished medium. Then, Massoia lactone was released from the produced liamocins. The released Massoia lactone loaded in the nanoemulsions could be used to actively damage cell wall and cell membrane of both spores and mycelia of Aspergillus flavus, leading to its cell necrosis. Massoia lactone loaded in the nanoemulsions also actively inhibited cell growth of A. flavus, its conidia production and aflatoxin biosynthesis on peanuts, indicating that Massoia lactone loaded in the nanoemulsions had highly potential application in controlling cell growth of A. flavus and aflatoxin biosynthesis in foods and feedstuffs.
In vivo and in vitro metabolite profiling of nirmatrelvir using LC–Q‐ToF–MS/MS along with the in silico approaches for prediction of metabolites and their toxicity
Authors: Chaganti Sowmya , Kushwah Bhoopendra Singh , Velip Laximan , Tiwari Shristy S. , Chilvery Shrilekha , Godugu Chandraiah , Samanthula Gananadhamu
Published: February 2024

Nirmatrelvir (NRV), a 3C‐like protease or Mpro inhibitor of SARS‐CoV‐2, is used for the treatment of COVID‐19 in adult and paediatric patients. The present study was accomplished to investigate the comprehensive metabolic fate of NRV using in vitro and in vivo models. The in vitro models used for the study were microsomes (human liver microsomes, rat liver microsomes, mouse liver microsomes) and S9 fractions (human liver S9 fractions and rat liver S9 fractions) with the appropriate cofactors, whereas Sprague–Dawley rats were used as the in vivo models. Nirmatrelvir was administered orally to Sprague–Dawley rats, which was followed by the collection of urine, faeces and blood at pre‐determined time intervals. Protein precipitation was used as the sample preparation method for all the samples. The samples were then analysed by liquid chromatography–quadrupole time‐of‐flight tandem mass spectrometry (LC‐Q‐ToF‐MS/MS) using an Acquity BEH C18 column with 0.1% formic acid and acetonitrile as the mobile phase. Four metabolites were found to be novel, which were formed via amide hydrolysis, oxidation and hydroxylation. Furthermore, an in silico analysis was performed using Meteor Nexus software to predict the probable metabolic changes of NRV. The toxicity and mutagenicity of NRV and its metabolites were also determined using DEREK Nexus and SARAH Nexus.
Synthesis, Antimicrobial Activities, and Molecular Modeling Studies of Agents for the Sortase A Enzyme
Authors: Tatar Yilmaz Gizem , Yayli Nurettin , Tüzüner Tamer , Bozdal Gözde , Salmanli Merve , Renda Gülin , Korkmaz Büşra , Bozdeveci Arif , Alpay Karaoğlu Şengül
Published: February 2024

Sortase A (SrtA) is an attractive target for developing new anti‐infective drugs that aim to interfere with essential virulence mechanisms, such as adhesion to host cells and biofilm formation. Herein, twenty hydroxy, nitro, bromo, fluoro, and methoxy substituted chalcone compounds were synthesized, antimicrobial activities and molecular modeling strategies against the SrtA enzyme were investigated. The most active compounds were found to be T2, T4, and T19 against Streptococcus mutans (S. mutans) with MIC values of 1.93, 3.8, 3.94 μg/mL, and docking scores of −6.46, −6.63, −6.73 kcal/mol, respectively. Also, these three active compounds showed better activity than the chlorohexidine (CHX) (MIC value: 4.88 μg/mL, docking score: −6.29 kcal/mol) in both in vitro and in silico. Structural stability and binding free energy analysis of S.mutans SrtA with active compounds were measured by molecular dynamic (MD) simulations throughout 100 nanoseconds (ns) time. It was observed that the stability of the critical interactions between these compounds and the target enzyme was preserved. To prove further, in vivo biological evaluation studies could be conducted for the most promising precursor compounds T2, T4, and T19, and it might open new avenues to the discovery of more potent SrtA inhibitors.
Pterostilbene protects against H2O2‐induced oxidative stress by regulating GAS6/Axl signaling in HL‐1 cells
Authors: Di Wencheng , Zhao Aizhen , Li Xiaoru , Chen Junmin , Dai Yongbin , Li Jiawen , Lei Wangrui , Yang Yang , Lu Hongzhou
Published: February 2024

Pterostilbene (PTE, trans‐3,5‐dimethoxy‐4′‐hydroxystilbene), a natural plant polyphenol, possesses numerous pharmacological effects, including antioxidant, antidiabetic, antiatherosclerotic, and neuroprotective aspects. This study aims to investigate whether PTE plays a protective role against oxidative stress injury by GAS6/Axl signaling pathway in cardiomyocytes. Hydrogen peroxide (H2O2)‐induced oxidative stress HL‐1 cells were used as models. The mechanism by which PTE protected oxidative stress is investigated by combining cell viability, cell ROS levels, apoptosis assay, molecular docking, quantitative real‐time PCR, and western blot analysis. GAS6 shRNA was performed to investigate the involvement of GAS6/Axl pathways in PTE's protective role. The results showed that PTE treatment improved the cell morphology and viability, and inhibited the apoptosis rate and ROS levels in H2O2‐injured HL‐1 cells. Particularly, PTE treatment upregulated the levels of GAS6, Axl, and markers related to oxidative stress, apoptosis, and mitochondrial function related. Molecular docking showed that PTE and GAS6 have good binding ability. Taken together, PTE plays a protective role against oxidative stress injury through inhibiting oxidative stress and apoptosis and improving mitochondrial function. Particularly, GAS6/Axl axis is the surprisingly prominent in the PTE‐mediated pleiotropic effects.
Phylogeny‐guided Characterization of Bacterial Hydrazine Biosynthesis Mediated by Cupin/methionyl tRNA Synthetase‐like Enzymes
Authors: Matsuda Kenichi , Nakahara Yuto , Choirunnisa Atina Rizkiya , Arima Kuga , Wakimoto Toshiyuki
Published: February 2024

Cupin/methionyl‐tRNA synthetase (MetRS)‐like didomain enzymes catalyze nitrogen‐nitrogen (N−N) bond formation between Nω‐hydroxylamines and amino acids to generate hydrazines, key biosynthetic intermediates of various natural products containing N−N bonds. While the combination of these two building blocks leads to the creation of diverse hydrazine products, the full extent of their structural diversity remains largely unknown. To explore this, we herein conducted phylogeny‐guided genome‐mining of related hydrazine biosynthetic pathways consisting of two enzymes: flavin‐dependent Nω‐hydroxylating monooxygenases (NMOs) that produce Nω‐hydroxylamine precursors and cupin/MetRS‐like enzymes that couple the Nω‐hydroxylamines with amino acids via N−N bonds. A phylogenetic analysis identified the largely unexplored sequence spaces of these enzyme families. The biochemical characterization of NMOs demonstrated their capabilities to produce various Nω‐hydroxylamines, including those previously not known as precursors of N−N bonds. Furthermore, the characterization of cupin/MetRS‐like enzymes identified five new hydrazine products with novel combinations of building blocks, including one containing non‐amino acid building blocks: 1,3‐diaminopropane and putrescine. This study substantially expanded the variety of N−N bond forming pathways mediated by cupin/MetRS‐like enzymes.
Ruthenium NNN‐Based Pincer Complexes with Metal Ligand Cooperation as Catalysts for N‐Methylation of Anilines and Nitroarenes with Methanol as a C1 Source
Authors: Garg Nitish K. , Goriya Yogesh , Manojveer Seetharaman , Wendt Ola F. , Johnson Magnus T.
Published: February 2024

A novel phosphine‐free ruthenium pincer complex based on an NNN pincer ligand has been prepared and fully characterized. The complex was subsequently employed as an efficient catalyst for the N‐methylation of amines and the direct N‐methylation of nitroarenes using methanol as a C1 source under mild reaction conditions following the borrowing‐hydrogen approach. Both of the catalytic transformations were performed with only catalytic amounts of base under closed air conditions without using any other additives.
Metal‐Organic Framework Catalyzed Hydrogen Atom Transfer for Photocatalytic Organic Synthetic Applications
Authors: Ouyang Jing , Quan Yangjian
Published: February 2024

This concept paper aims to summarize recent research on the design and synthetic applications of metal‐organic frameworks (MOFs)‐based hydrogen atom transfer (HAT) catalysts. Functional MOFs have emerged as highly promising heterogeneous catalysts, leveraging their tunable, ordered structure and abundant active sites to enhance catalytic efficiency in various reactions. HAT, a versatile method for generating active open‐shell radical species through selective hydrogen abstraction, has been well explored in homogeneous photocatalysis. In contrast, heterogeneous HAT catalysis remains less developed, albeit their great potential in industry. This paper will provide a timely overview of the advancements in MOFs‐based HAT photocatalysis, classified according to catalytic centers including aromatic ketones, polyoxometalates, xanthene dyes, thiols, and alcohols, highlighting their design principles and practical applications in photocatalytic organic synthesis.
Tailoring the Properties of Gel Polymer Electrolytes for Sodium‐Ion Batteries Using Ionic Liquids: A Review
Authors: Gabryelczyk Agnieszka , Swiderska‐Mocek Agnieszka
Published: February 2024

Ionic liquids are an extraordinary group of compounds, fully ionic in structure like inorganic salts but with low melting points, that resemble organic molecular solvents. Their chemical, electrochemical, and thermal stability is what draws the attention and enables their use in many applications, including electrochemical power sources. Even though they are no longer considered eco‐friendly because of nonnegligible toxicity and long bioaccumulation, they can still be efficiently recovered, purified, and reused. These attributes can be harvested to enhance the properties of gel polymer electrolytes for the emerging sodium‐ion batteries. The variety of anions and cations for ILs and their influence on the final properties of the compound opens the road to tuning the properties of gel polymer electrolytes. Ionic liquids as plasticizers constitute a major part of gel polymer electrolytes (average of 70 wt%) and hence, they affect the fundamental properties of gel electrolytes like ionic conductivity and electrochemical window. They also improve the safety features of sodium‐ion batteries, which is relevant for their anticipated applications in stationary energy storage and electric vehicles. The presented review paper aims to explain the relationship between the cation and anion in ionic liquid and the properties of gel electrolytes for sodium‐ion batteries.