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Due to the occlusion of the anterior choroidal artery (AChA), ischemic strokes are described with the classic clinical triad, namely hemiplegia, hemianesthesia, and homonymous hemianopsia. The aim of this study is to document the characteristic clinical presentation and course of AChA infract cases. We describe five cases with acute infarction in the distribution of the AChA, admitted to the Neurological Department of the University General Hospital of Larissa. Results: All cases presented with hemiparesis and lower facial nerve palsy, while four of them had dysarthria, and two patients exhibited ataxia. Two cases underwent intravenous thrombolysis. A notable feature was the worsening of the clinical course, specifically the exacerbation of upper limb weakness within 48 h. Stabilization occurred after the third day, with the final development of a more severe clinical presentation than the initial one. Additionally, muscle weakness was more severe in the upper limb than in the lower limb. The recovery of upper limb function was poor in the three-month follow-up for the four cases. While vascular brain episodes are characterized by sudden onset, in AChA infraction, the clinical onset can be gradually developed over a few days, with a greater burden on the upper limb and poorer recovery.

Alzheimer's Disease (AD) is a progressive neurodegenerative disease and the main cause of dementia. Its etiology remains largely unclear, though genetic and environmental factors appear to confer susceptibility to AD development. This study assessed the role of ATP-binding Cassette A Subfamily 7 (ABCA7) genetic polymorphisms, as ongoing research suggests they have a role in the development of AD. We conducted a PubMed, Google Scholar, and Scopus search to identify and assess all AD studies examining ABCA7 variants in different populations and ethnicities. The last search was conducted on February 8, 2023. Inclusion and exclusion criteria were applied and only the studies that met the inclusion criteria were included in this review. Seventeen studies were finally included. According to the results, ABCA7 variants infer different risks for AD among populations with different ancestries. African American populations show a higher risk for AD, carrying the five novel variants rs115550680, rs142076058, rs10405305, rs3764647, and rs567222111. Asian populations also have an increased risk for AD, harboring three variants. ABCA7 genetic variability contributes to AD development and shows racial disparities. African American and Asian populations seem to be at greater risk of developing AD. These results may assist future research efforts for the early and accurate diagnosis of AD. Moreover, further exploration of the mechanisms of ABCA7 in the context of AD could identify potential therapeutic targets.

(1) Introduction: There have been numerous reports on the neuroinvasive competence of SARS-CoV-2. Here, we present a case with anti-MOG positive bilateral optic neuritis and brainstem encephalitis secondary to COVID-19 infection. Additionally, we present a review of the current literature regarding the manifestation of anti-MOG positive optic neuritis as well as anti-MOG positive encephalitis after COVID-19 infection. (2) Case Report: A 59-year-old female patient, with a recent history of COVID-19 infection, presented a progressive reduction of visual acuity and bilateral retrobulbar pain for the last 20 days. An ophthalmological examination revealed a decreased visual acuity (counting fingers) and a bilateral papilledema. An MRI scan of the brain revealed a mild thickening of the bilateral optic nerves and high-intensity lesions in the medial and right lateral pons. A high titer of IgG and IgM antibodies against SARS-CoV-2 in serum and antibodies against myelin oligodendrocyte glycoprotein (anti-MOG) in serum and CSF were revealed. The diagnosis of anti-MOG brainstem encephalitis and optic neuritis was set. (3) Conclusions: The history of COVID-19 infection should raise awareness about these autoimmune and infection-triggered diseases, such as anti-MOG antibody disease.

The main objective of the AgroFossilFree Horizon2020 project is to create a framework under which all core stakeholders can cooperate to evaluate and promote the currently available fossil-energy-free technologies and strategies (FEFTS) in EU agriculture in a cost efficient manner. AgroFossilFree has implemented an online and interactive approach to communication, interaction and knowledge sharing and exchanging through the use of a specifically designed ICT tool, the “AgEnergy Platform”, which deploys the collected information and knowledge on FEFTS in the form of easily accessible end-user material facilitating searching through the use of filters. Still, the question remains of how can you choose which one is the most appropriate one or the most cost-effective one for each farm. The answer to that in reality comes after a detailed study on a per farm basis. An intermediate level was developed to bridge these two extremes, that can provide a first insight on which FEFTS probably suits best to each farm using minimal user inputs. This Decision Support Tool (DST) based on Fuzzy Cognitive Maps, is integrated seamlessly within the AgroFossilFree platform and allows users to get a ranking of the technologies most suitable for their farm. Essentially, the DST mimics the consultation process of a number of experts if these experts were in the same room evaluating the input data provided by the end-user to propose the most effective action. This paper presents the theory, development steps undertaken and the final implementation of this DST in the AgroFossilFree website. The approach undertaken can be replicated to increase the functionality of other comparable platforms in the Agricultural sector and beyond.

Background: Microglial activation is considered to assume a role in the pathogenesis of Amyotrophic Lateral Sclerosis (ALS). To date, the relationship between ALS and the rs3865444 polymorphism of the cluster of differentiation 33 (CD33) has not been explored. The current report aimed to investigate the potential connection between CD33 rs3865444 and ALS. Methods: Patients diagnosed with sporadic ALS according to the revised El Escorial criteria, as well as age and sex matched community controls, were enrolled. Two evenly numbered, age and sex matched groups of 155 participants each were genotyped. Results: No association was found between rs3865444 and ALS [log-additive odds ratio (OR) = 0.83 (0.57, 1.22), over-dominant OR = 0.86 (0.55, 1.36), recessive OR = 0.73 (0.25, 2.17), dominant OR = 0.82 (0.52, 1.29), co-dominant OR1 = 0.68 (0.23, 2.05) and co-dominant OR2 = 0.84 (0.53, 1.33)]. Moreover, no relationship was established between rs3865444 and the age of ALS onset based on both unadjusted and sex adjusted Cox-proportional hazards models. Finally, no association between rs3865444 and ALS was found in subgroup analyses based on the site of ALS onset (bulbar or spinal) and sex. Conclusions: The current analysis is the first to report that rs3865444 is not linked to ALS. Larger multi-racial studies are required to confirm these findings.

Various diseases and pests cause serious damage to vegetable crops during the growing season and after harvesting. Growers attempt to minimize losses by protecting their crops, starting with seed and seedling treatments and followed by monitoring their stands. In many cases, synthetic pesticide treatments are applied. Integrated pest management is currently being employed to minimize the impact of pesticides upon human health and the environment. Over the last few years, “smart” approaches have been developed and adopted in practice to predict, detect, and quantify phytopathogen occurrence and contamination. Our review assesses the currently available ready-to-use tools and methodologies that operate via visual estimation, the detection of proteins and DNA/RNA sequences, and the utilization of brand-new innovative approaches, highlighting the availability of solutions that can be used by growers during the process of diagnosing pathogens.

VoIP services, in general, and session initiation protocol (SIP) ones, in particular, continue to grow at a fast pace and have already become a key component of next-generation networks. Despite this proliferation, SIP-based services expose a large attack surface for perpetrators, especially those who seek to cause denial of service (DoS). While so far, a plethora of works in the literature have been devoted to the detection of DoS attacks in SIP ecosystems, the focus is on those which exploit SIP headers neglecting the message body. In an effort to fill this gap, this paper concentrates on the detection of DoS attacks, which, instead, capitalize on the session description protocol (SDP) part of SIP requests. To this end, we not only scrutinize this ilk of attacks and demonstrate their effect against the end-user but also develop an open-source extensible SDP parser module capable of detecting intentionally or unintentionally crafted SDP segments parasitizing in SIP requests. Following a firewall-based logic, currently, the parser incorporates 100 different rules organized in four categories (policies) based on the corresponding RFC 4566. Through extensive experimentation, we show that our scheme induces negligible overhead in terms of processing time when working as a software module in either the SIP proxy or a separate machine in front of the latter.

Background: Dystonia is a movement disorder with high heterogeneity regarding phenotypic appearance and etiology that occurs in both sporadic and familial forms. The etiology of the disease remains unknown. However, there is increasing evidence suggesting that a small number of gene alterations may lead to dystonia. Although pathogenic variants to the familial type of dystonia have been extensively reviewed and discussed, relatively little is known about the contribution of single-nucleotide polymorphisms (SNPs) to dystonia. This review focuses on the potential role of SNPs and other variants in dystonia susceptibility. Methods: We searched the PubMed database for peer-reviewed articles published in English, from its inception through January 2018, that concerned human studies of dystonia and genetic variants. The following search terms were included: “dystonia” in combination with the following terms: 1) “polymorphisms” and 2) “SNPs” as free words. Results: A total of 43 published studies regarding TOR1A, BDNF, DRD5, APOE, ARSG, NALC, OR4X2, COL4A1, TH, DDC, DBH, MAO, COMT, DAT, GCH1, PRKRA, MR-1, SGCE, ATP1A3, TAF1, THAP1, GNAL, DRD2, HLA-DRB, CBS, MTHFR, and MS genes, were included in the current review. Discussion: To date, a few variants, which are possibly involved in several molecular pathways, have been related to dystonia. Large cohort studies are needed to determine robust associations between variants and dystonia with adjustment for other potential cofounders, in order to elucidate the pathogenic mechanisms of dystonia and the net effect of the genes.

Politicians and the general public are concerned about climate change, water scarcity, and the constant reduction in agricultural land. Water reserves are scarce in many regions in the world, negatively affecting agricultural productivity, which makes it a necessity to introduce sustainable water resource management. Nowadays, there is a number of commercial IoT systems for irrigation scheduling, helping farmers to manage and save water. However, these systems focus on using the available fresh water sources, without being able to manage alternative water sources. In this study, an Arduino-based low-cost IoT system for automated irrigation scheduling is developed and implemented, which can provide measurements of water parameters with high precision using low-cost sensors. The system used weather station data combined with the FAO56 model for computing the water requirements for various crops, and it was capable of handling and monitoring different water streams by supervising their quality and quantity. The developed IoT system was tested in several field trials, to evaluate its capabilities and functionalities, including the sensors’ accuracy, its autonomous controlling and operation, and its power consumption. The results of this study show that the system worked efficiently on the management and monitoring of different types of water sources (rainwater, groundwater, seawater, and wastewater) and on automating the irrigation scheduling. In addition, it was proved that the system is can be used for long periods of time without any power source, making it ideal for using it on annual crops.

Over the past decade, Greece and other Mediterranean countries have witnessed the emergence and resurgence of several vector-borne diseases (VBDs), posing important public health challenges and threatening the tourist industry. An essential prerequisite for the design and execution of efficient and sustainable context-specific VBD control programmes is the establishment of integrative entomological and epidemiological surveillance systems. However, the monitoring and management of surveillance datasets (often chronologically fragmented, scattered in regional health district offices and partially accessible upon requisition), as well as their transformation into actionable information, is a complex undertaking. In light of aiding and optimizing vector control efforts in the Mediterranean Basin, we developed VectorMap-GR, an online, open access, operational management tool for entomological and complementary epidemiological monitoring data. The toolʼs key components are a set of controlled vocabularies (ontologies) running throughout the system, the systemʼs database and a map interface for data querying and display. The tool supports transformation of raw data into operationally relevant information (i.e. customized maps, charts, tables and reports) in a highly interactive fashion achieved through query filters and the ArcGIS technology embedded in the system. End-users may search for and obtain information on (i) the mosquito fauna composition, abundance and spatiotemporal dynamics; (ii) the mosquito insecticide resistance status and underlying resistance mechanisms; (iii) the occurrence of VBD pathogens and infections in vectors, animals and humans; and (iv) operationally relevant physical feature georeferenced datasets (e.g. mosquito breeding sites). VectorMap-GR was pilot implemented during 2018–2020 in a mosquito control programme in the Region of Crete (southern Greece). The programmeʼs control efforts coupled with VectorMap-GR pilot implementation phase, very likely contributed to the reduction of vector population numbers and the prevention of human VBD occurrences, recorded in this period.

Wireless sensor networks (WSN) have found wide applications in many fields (such as agriculture) over last few years, and research interest is constantly increasing. However, power supply to the sensor nodes remains an issue to be resolved. Batteries are usually used to power the sensor nodes, but they have a limited lifetime, so solar energy harvesters are a good alternative solution. This study provides a comparative analysis between battery and solar energy harvesters for sensor nodes used for soil water monitoring. Experimental results show that small-sized solar panels with low-power energy harvester circuits and rechargeable batteries distinctly outperform secondary batteries in outdoor and continuous-operation applications. The power level of the energy storage device of sensor node 1, which was powered by a small PV panel, remained constantly close to 90% for all days. The power of the other three nodes, which were powered by a rechargeable battery, was initially at 100% of the charge and gradually started to reduce. Sensor node 1 performed a total of 1288 activations during the experimental period, while sensor nodes 2 and 4 behaved satisfactorily and performed a total of 781 and 803 activations, respectively. In contrast, sensor node 3 did not exhibit the same behavior throughout the experiments.

Background and Objectives: To date, only one study has investigated the association between the rs616147 polymorphism of the Myelin-associated Oligodendrocyte Basic Protein (MOBP) locus and Amyotrophic Lateral Sclerosis (ALS). Materials and Methods: A case-control study was performed. Patients with definite sporadic ALS were prospectively and consecutively recruited from the inpatient and outpatient clinics of the Neurology Department of the General University Hospital of Larissa, Central Greece. Community based, age and sex matched healthy individuals with a free personal and family history constituted the control group. Results: A total of 155 patients with definite sporadic ALS and an equal number of healthy controls were genotyped. The power of our sample size was slightly above 80% and MOBP rs616147 was determined to be in Hardy-Weinberg Equilibrium among healthy participants (p = 1.00). According to the univariate analysis, there was no significant relationship between rs616147 and ALS [log-additive OR = 0.85 (0.61, 1.19), over-dominant OR = 0.73 (0.46, 1.15), recessive OR = 1.02 (0.50, 2.09), dominant OR = 0.74 (0.47, 1.16), co-dominant OR1 = 0.71 (0.44, 1.14) and co-dominant OR2 = 0.88 (0.42, 1.84). Additionally, the effect of rs616147 on the age of ALS onset was determined insignificant using both unadjusted and adjusted (sex, site of onset) cox-proportional models. Finally, rs616147 was not related to the site of ALS onset. Conclusions: Our study is the first to report the absence of an association between MOBP rs616147 and ALS among individuals of Greek ancestry. Additional, larger nationwide and multi-ethnic studies are warranted to shed light on the connection between rs616147 and ALS.

Introduction. Pseudomyxoma peritonei (PMP) is an uncommon surgical entity. We report a case of aggressive disease with an unusual clinical presentation and we analyze current data on diagnosis and management of PMP. Case Presentation. A 71-year-old male patient presented with intermittent diarrhea and loss of appetite during the last two months, without any other classic symptoms of PMP. The clinical examination was misleading due to patient’s obesity. The radiological evaluation revealed ascites of the abdomen and possible mucocele of the appendix, whereas the laboratory exams showed high values of specific tumour markers. The patient underwent an exploratory laparotomy for definite diagnosis. Biopsies and immunohistochemical examination confirmed the diagnosis of an aggressive and extended peritoneal mucinous carcinomatosis (PMCA). The patient was programmed for adjuvant systematic chemotherapy, which was not completed due to progression of the disease. Conclusions. Progressed PMP can present with unspecific symptoms that mislead diagnosis. Cytoreductive surgery in combination with systematic chemotherapy could be appropriate for aggressive PMCA, even with an unfavourable prognosis.

Gastrointestinal stromal tumors (GIST) are uncommon mesenchymal spindle-cell or epithelioid neoplasms, located mainly with higher frequency in the stomach and small bowel. GISTs represent the majority of primary non-epithelial neoplasms of the digestive tract, most frequently expressing the KIT protein a transmembrane tyrosine kinase receptor for stem cell factor. Extra-gastrointestinal stromal tumors tend to present In fewer than 5% of cases; they originate primarily from the mesentery, omentum or peritoneum. Furthermore, these extra-gastrointestinal tumors (EGIST) tend to be more common in patients over the age of 50 years. EGISTs are neoplasms with overlapping immunohistological features, occurring in the abdomen outside the gastrointestinal tract with no connection to the gastric or intestinal wall. We describe here a rare case of EGIST of the lesser omentum and report the clinical, macroscopic, immunohistological and radiological features of an EGIST arising in the lesser omentum of a 63-year old man. Clinical course and the prognostic factors of such lesions will also be discussed. EGISTs in the lesser omentum can grow slowly and remain silent despite a large tumor size. In most cases, a pre-operative diagnosis is not possible, and the patient undergoes a surgical operation for the generic diagnosis of abdominal mass . During the intervention it is important to achieve a complete removal of the mass and to examine every possible adhesion to the gastrointestinal wall.

Cell dispersion from a confined area is fundamental in a number of biological processes, including cancer metastasis. To date, a quantitative understanding of the interplay of single-cell motility, cell proliferation, and intercellular contacts remains elusive. In particular, the role of E- and N-cadherin junctions, central components of intercellular contacts, is still controversial. Combining theoretical modeling with in vitro observations, we investigate the collective spreading behavior of colonies of human cancer cells (T24). The spreading of these colonies is driven by stochastic single-cell migration with frequent transient cell-cell contacts. We find that inhibition of E- and N-cadherin junctions decreases colony spreading and average spreading velocities, without affecting the strength of correlations in spreading velocities of neighboring cells. Based on a biophysical simulation model for cell migration, we show that the behavioral changes upon disruption of these junctions can be explained by reduced repulsive excluded volume interactions between cells. This suggests that in cancer cell migration, cadherin-based intercellular contacts sharpen cell boundaries leading to repulsive rather than cohesive interactions between cells, thereby promoting efficient cell spreading during collective migration., (Copyright © 2021 Biophysical Society. Published by Elsevier Inc. All rights reserved.)

Chlorophyll and heme are among the "pigments of life", tetrapyrrolic structures, without which life on Earth would not be possible. Their catabolites, the phyllobilins and the bilins, respectively, share not only structural features, but also a similar story: Long considered waste products of detoxification processes, important bioactivities for both classes have now been demonstrated. For phyllobilins, however, research on physiological roles is sparse. Here, we introduce actin, the major component of the cytoskeleton, as the first discovered target of phyllobilins and as a novel target of bilins. We demonstrate the inhibition of actin dynamics in vitro and effects on actin and related processes in cancer cells. A direct interaction with G-actin is shown by in silico studies and confirmed by affinity chromatography. Our findings open a new chapter in bioactivities of tetrapyrroles-especially phyllobilins-for which they form the basis for broad implications in plant science, ecology, and physiology., (© 2021 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The role of two-pore channel 2 (TPC2), one of the few cation channels localized on endolysosomal membranes, in cancer remains poorly understood. Here, we report that TPC2 knockout reduces proliferation of cancer cells in vitro, affects their energy metabolism, and successfully abrogates tumor growth in vivo. Concurrently, we have developed simplified analogs of the alkaloid tetrandrine as potent TPC2 inhibitors by screening a library of synthesized benzyltetrahydroisoquinoline derivatives. Removal of dispensable substructures of the lead molecule tetrandrine increases antiproliferative properties against cancer cells and impairs proangiogenic signaling of endothelial cells to a greater extent than tetrandrine. Simultaneously, toxic effects on non-cancerous cells are reduced, allowing in vivo administration and revealing a TPC2 inhibitor with antitumor efficacy in mice. Hence, our study unveils TPC2 as valid target for cancer therapy and provides easily accessible tetrandrine analogs as a promising option for effective pharmacological interference., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Attachment of adhesive molecules on cell culture surfaces to restrict cell adhesion to defined areas and shapes has been vital for the progress of in vitro research. In currently existing patterning methods, a combination of pattern properties such as stability, precision, specificity, high-throughput outcome, and spatiotemporal control is highly desirable but challenging to achieve. Here, we introduce a versatile and high-throughput covalent photoimmobilization technique, comprising a light-dose-dependent patterning step and a subsequent functionalization of the pattern via click chemistry. This two-step process is feasible on arbitrary surfaces and allows for generation of sustainable patterns and gradients. The method is validated in different biological systems by patterning adhesive ligands on cell-repellent surfaces, thereby constraining the growth and migration of cells to the designated areas. We then implement a sequential photopatterning approach by adding a second switchable patterning step, allowing for spatiotemporal control over two distinct surface patterns. As a proof of concept, we reconstruct the dynamics of the tip/stalk cell switch during angiogenesis. Our results show that the spatiotemporal control provided by our "sequential photopatterning" system is essential for mimicking dynamic biological processes and that our innovative approach has great potential for further applications in cell science.

Severe side effects often restrict clinical application of the widely used chemotherapeutic drug doxorubicin. In order to decrease required substance concentrations, new concepts for successful combination therapy are needed. Since doxorubicin causes DNA damage, combination with compounds that modulate DNA repair could be a promising strategy. Very recently, a role of nuclear actin for DNA damage repair has been proposed, making actin a potential target for cancer therapy in combination with DNA-damaging therapeutics. This is of special interest, since actin-binding compounds have not yet found their way into clinics. We find that low-dose combination treatment of doxorubicin with the actin polymerizer chondramide B (ChB) synergistically inhibits tumor growth in vivo. On the cellular level we demonstrate that actin binders inhibit distinctive double strand break (DSB) repair pathways. Actin manipulation impairs the recruitment of replication factor A (RPA) to the site of damage, a process crucial for homologous recombination. In addition, actin binders reduce autophosphorylation of DNA-dependent protein kinase (DNA-PK) during nonhomologous end joining. Our findings substantiate a direct involvement of actin in nuclear DSB repair pathways, and propose actin as a therapeutic target for combination therapy with DNA-damaging agents such as doxorubicin.

Combination chemotherapy has proven to be a favorable strategy to treat acute leukemia. However, the introduction of novel compounds remains challenging and is hindered by a lack of understanding of their mechanistic interactions with established drugs. In the present study, we demonstrate a highly increased response of various acute leukemia cell lines, drug-resistant cells and patient-derived xenograft cells by combining the recently introduced protein disulfide isomerase inhibitor PS89 with cytostatics. In leukemic cells, a proteomics-based target fishing approach revealed that PS89 affects a whole network of endoplasmic reticulum homeostasis proteins. We elucidate that the strong induction of apoptosis in combination with cytostatics is orchestrated by the PS89 target B-cell receptor-associated protein 31, which transduces apoptosis signals at the endoplasmic reticulum -mitochondria interface. Activation of caspase-8 and cleavage of B-cell receptor-associated protein 31 stimulate a pro-apoptotic crosstalk including release of calcium from the endoplasmic reticulum and an increase in the levels of reactive oxygen species resulting in amplification of mitochondrial apoptosis. The findings of this study promote PS89 as a novel chemosensitizing agent for the treatment of acute leukemia and uncovers that targeting the endoplasmic reticulum - mitochondrial network of cell death is a promising approach in combination therapy., (Copyright© 2019 Ferrata Storti Foundation.)

Actin has emerged as a versatile regulator of gene transcription. Cytoplasmatic actin regulates mechanosensitive-signaling pathways such as MRTF-SRF and Hippo-YAP/TAZ. In the nucleus, both polymerized and monomeric actin directly interfere with transcription-associated molecular machineries. Natural actin-binding compounds are frequently used tools to study actin-related processes in cell biology. However, their influence on transcriptional regulation and intranuclear actin polymerization is poorly understood to date. Here, we analyze the effects of two representative actin-binding compounds, Miuraenamide A (polymerizing properties) and Latrunculin B (depolymerizing properties), on transcriptional regulation in primary cells. We find that actin stabilizing and destabilizing compounds inversely shift nuclear actin levels without a direct influence on polymerization state and intranuclear aspects of transcriptional regulation. Furthermore, we identify Miuraenamide A as a potent inducer of G-actin-dependent SRF target gene expression. In contrast, the F-actin-regulated Hippo-YAP/TAZ axis remains largely unaffected by compound-induced actin aggregation. This is due to the inability of AMOTp130 to bind to the amorphous actin aggregates resulting from treatment with miuraenamide. We conclude that actin-binding compounds predominantly regulate transcription via their influence on cytoplasmatic G-actin levels, while transcriptional processes relying on intranuclear actin polymerization or functional F-actin networks are not targeted by these compounds at tolerable doses.

Water-soluble polyisocyanopeptides (PICs) are a new class of synthetic polymers that mimic natural protein-based filaments. Their unique semiflexible properties combined with a length of several hundred nanometers have recently enabled a number of biomedical applications ranging from tissue engineering to cancer immunotherapy. One crucial step toward the further development of PICs for these applications is the efficient and controlled synthesis and purification of PIC-biomolecule conjugates. Considering the large size of PICs and the biomolecules to be conjugated, conjugation reactions do usually not proceed to completion due to steric effects. As a consequence, purification of the reaction mixture is necessary to separate the obtained bioconjugates from unreacted biomolecules. As a direct result of the semiflexible nature of PICs, standard polymer and protein purification methods based on molecular weight have not been successful. Here, we introduce a new affinity-based purification method utilizing biotin as an affinity tag. PICs decorated with a controlled and tunable density of biotin molecules (biotinPICs) were efficiently bound to and eluted from a monoavidin resin in buffered aqueous solution. Using these biotinPICs, two different protein conjugates were synthesized, one carrying the enzyme alkaline phosphatase (PhoA) and the other T-cell activating anti-CD3 antibodies. The resulting biotinPIC-protein conjugates were successfully obtained in high purity (>90%) and without any loss of protein activity. The high purity greatly simplifies the analysis of biotinPIC bioconjugates, such as the determination of the average number of biomolecules conjugated per biotinPIC chain. Most importantly, it allows for the direct and straightforward application of the obtained bioconjugates in the desired applications. The new method developed may further be adapted for the purification of other advanced bioconjugates that are difficult to obtain in high purity with the available standard methods.

Lipase immobilization is frequently used for altering the catalytic properties of these industrially used enzymes. Many lipases bind strongly to hydrophobic surfaces where they undergo interfacial activation. Candida antarctica lipase B (CalB), one of the most commonly used biocatalysts, is frequently discussed as an atypical lipase lacking interfacial activation. Here we show that CalB displays an enhanced catalytic rate for large, bulky substrates when adsorbed to a hydrophobic interface composed of densely packed alkyl chains. We attribute this increased activity of more than 7-fold to a conformational change that yields a more open active site. This hypothesis is supported by molecular dynamics simulations that show a high mobility for a small "lid" (helix α5) close to the active site. Molecular docking calculations confirm that a highly open conformation of this helix is required for binding large, bulky substrates and that this conformation is favored in a hydrophobic environment. Taken together, our combined approach provides clear evidence for the interfacial activation of CalB on highly hydrophobic surfaces. In contrast to other lipases, however, the conformational change only affects large, bulky substrates, leading to the conclusion that CalB acts like an esterase for small substrates and as a lipase for substrates with large alcohol substituents.