Pub Date : 2022-11-21DOI: 10.3390/biophysica2040043
David Polanco, Alejandra Carrancho, P. Gracia, N. Cremades
Protein amyloid aggregation has been associated with more than 50 human disorders, including the most common neurodegenerative disorders Alzheimer’s and Parkinson’s disease. Interfering with this process is considered as a promising therapeutic strategy for these diseases. Our understanding of the process of amyloid aggregation and its role in disease has typically been limited by the use of ensemble-based biochemical and biophysical techniques, owing to the intrinsic heterogeneity and complexity of the process. Single-molecule techniques, and particularly diffusion-based single-molecule fluorescence approaches, have been instrumental to obtain meaningful information on the dynamic nature of the fibril-forming process, as well as the characterisation of the heterogeneity of the amyloid aggregates and the understanding of the molecular basis of inhibition of a number of molecules with therapeutic interest. In this article, we reviewed some recent contributions on the characterisation of the amyloid aggregation process, the identification of distinct structural groups of aggregates in homotypic or heterotypic aggregation, as well as on the study of the interaction of amyloid aggregates with other molecules, allowing the estimation of the binding sites, affinities, and avidities as examples of the type of relevant information we can obtain about these processes using these techniques.
{"title":"Characterisation of Amyloid Aggregation and Inhibition by Diffusion-Based Single-Molecule Fluorescence Techniques","authors":"David Polanco, Alejandra Carrancho, P. Gracia, N. Cremades","doi":"10.3390/biophysica2040043","DOIUrl":"https://doi.org/10.3390/biophysica2040043","url":null,"abstract":"Protein amyloid aggregation has been associated with more than 50 human disorders, including the most common neurodegenerative disorders Alzheimer’s and Parkinson’s disease. Interfering with this process is considered as a promising therapeutic strategy for these diseases. Our understanding of the process of amyloid aggregation and its role in disease has typically been limited by the use of ensemble-based biochemical and biophysical techniques, owing to the intrinsic heterogeneity and complexity of the process. Single-molecule techniques, and particularly diffusion-based single-molecule fluorescence approaches, have been instrumental to obtain meaningful information on the dynamic nature of the fibril-forming process, as well as the characterisation of the heterogeneity of the amyloid aggregates and the understanding of the molecular basis of inhibition of a number of molecules with therapeutic interest. In this article, we reviewed some recent contributions on the characterisation of the amyloid aggregation process, the identification of distinct structural groups of aggregates in homotypic or heterotypic aggregation, as well as on the study of the interaction of amyloid aggregates with other molecules, allowing the estimation of the binding sites, affinities, and avidities as examples of the type of relevant information we can obtain about these processes using these techniques.","PeriodicalId":72401,"journal":{"name":"Biophysica","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46495558","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-19DOI: 10.3390/biophysica2040042
F. Goñi
In the 1960s, Biophysics was an unheard of scientific field in Spain, and even outside Spain, the distinction between Biophysics and Molecular Biology was not clear at the time. This paper describes briefly the developments that led to the foundation of the Spanish National Committee for Biophysics (1981) and of the Spanish Biophysical Society (1987), the incorporation of Spain into IUPAB and EBSA, and the normalized presence of Biophysics as a compulsory subject in undergraduate curricula in Spain.
{"title":"Birth and Early Steps of the Organization of Biophysics in Spain","authors":"F. Goñi","doi":"10.3390/biophysica2040042","DOIUrl":"https://doi.org/10.3390/biophysica2040042","url":null,"abstract":"In the 1960s, Biophysics was an unheard of scientific field in Spain, and even outside Spain, the distinction between Biophysics and Molecular Biology was not clear at the time. This paper describes briefly the developments that led to the foundation of the Spanish National Committee for Biophysics (1981) and of the Spanish Biophysical Society (1987), the incorporation of Spain into IUPAB and EBSA, and the normalized presence of Biophysics as a compulsory subject in undergraduate curricula in Spain.","PeriodicalId":72401,"journal":{"name":"Biophysica","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43599482","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-17DOI: 10.3390/biophysica2040041
E. Alizadeh, Dipayan Chakraborty, S. Ptasińska
Technological advancement has produced a variety of instruments and methods to generate electron beams that have greatly assisted in the extensive theoretical and experimental efforts devoted to investigating the effect of secondary electrons with energies approximately less than 100 eV, which are referred as low-energy electrons (LEEs). In the past two decades, LEE studies have focused on biomolecular systems, which mainly consist of DNA and proteins and their constituents as primary cellular targets of ionizing radiation. These studies have revealed that compared to other reactive species produced by high-energy radiation, LEEs have distinctive pathways and considerable efficiency in inducing lethal DNA lesions. The present work aims to briefly discuss the current state of LEE production technology and to motivate further studies and improvements of LEE generation techniques in relation to biological electron-driven processes associated with such medical applications as radiation therapy and cancer treatment.
{"title":"Low-Energy Electron Generation for Biomolecular Damage Inquiry: Instrumentation and Methods","authors":"E. Alizadeh, Dipayan Chakraborty, S. Ptasińska","doi":"10.3390/biophysica2040041","DOIUrl":"https://doi.org/10.3390/biophysica2040041","url":null,"abstract":"Technological advancement has produced a variety of instruments and methods to generate electron beams that have greatly assisted in the extensive theoretical and experimental efforts devoted to investigating the effect of secondary electrons with energies approximately less than 100 eV, which are referred as low-energy electrons (LEEs). In the past two decades, LEE studies have focused on biomolecular systems, which mainly consist of DNA and proteins and their constituents as primary cellular targets of ionizing radiation. These studies have revealed that compared to other reactive species produced by high-energy radiation, LEEs have distinctive pathways and considerable efficiency in inducing lethal DNA lesions. The present work aims to briefly discuss the current state of LEE production technology and to motivate further studies and improvements of LEE generation techniques in relation to biological electron-driven processes associated with such medical applications as radiation therapy and cancer treatment.","PeriodicalId":72401,"journal":{"name":"Biophysica","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45482525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-17DOI: 10.3390/biophysica2040040
G. Cottone, A. Cupane, M. Leone, V. Vetri, V. Militello
An overview of the biophysics activity at the Department of Physics and Chemistry Emilio Segrè of the University of Palermo is given. For forty years, the focus of the research has been on the protein structure–dynamics–function paradigm, with the aim of understanding the molecular basis of the relevant mechanisms and the key role of solvent. At least three research lines are identified; the main results obtained in collaboration with other groups in Italy and abroad are presented. This review is dedicated to the memory of Professors Massimo Ugo Palma, Maria Beatrice Palma Vittorelli, and Lorenzo Cordone, which were the founders of the Palermo School of Biophysics. We all have been, directly or indirectly, their pupils; we miss their enthusiasm for scientific research, their deep physical insights, their suggestions, their strict but always constructive criticisms, and, most of all, their friendship. This paper is dedicated also to the memory of Prof. Hans Frauenfelder, whose pioneering works on nonexponential rebinding kinetics, protein substates, and energy landscape have inspired a large part of our work in the field of protein dynamics.
{"title":"A Long Journey into the Investigation of the Structure–Dynamics–Function Paradigm in Proteins through the Activities of the Palermo Biophysics Group","authors":"G. Cottone, A. Cupane, M. Leone, V. Vetri, V. Militello","doi":"10.3390/biophysica2040040","DOIUrl":"https://doi.org/10.3390/biophysica2040040","url":null,"abstract":"An overview of the biophysics activity at the Department of Physics and Chemistry Emilio Segrè of the University of Palermo is given. For forty years, the focus of the research has been on the protein structure–dynamics–function paradigm, with the aim of understanding the molecular basis of the relevant mechanisms and the key role of solvent. At least three research lines are identified; the main results obtained in collaboration with other groups in Italy and abroad are presented. This review is dedicated to the memory of Professors Massimo Ugo Palma, Maria Beatrice Palma Vittorelli, and Lorenzo Cordone, which were the founders of the Palermo School of Biophysics. We all have been, directly or indirectly, their pupils; we miss their enthusiasm for scientific research, their deep physical insights, their suggestions, their strict but always constructive criticisms, and, most of all, their friendship. This paper is dedicated also to the memory of Prof. Hans Frauenfelder, whose pioneering works on nonexponential rebinding kinetics, protein substates, and energy landscape have inspired a large part of our work in the field of protein dynamics.","PeriodicalId":72401,"journal":{"name":"Biophysica","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45387826","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-11DOI: 10.3390/biophysica2040039
Chih Hung Lo
Tauopathies, including Alzheimer’s disease (AD), are a group of neurodegenerative disorders characterized by pathological aggregation of microtubule binding protein tau. The presence of tau neurofibrillary tangles, which are insoluble β-sheet fibrils, in the brain has been the histopathological hallmark of these diseases as their level correlates with the degree of cognitive impairment. However, recent studies suggest that tau oligomers, which are soluble proteins that are formed prior to insoluble fibrils, are the principal toxic species impairing neurons and inducing neurodegeneration. Targeting toxic tau oligomers is challenging, as they are mostly unstructured and adopting multiple conformations. The heterogeneity of tau oligomers is further illustrated by the different oligomeric species formed by various methods. The current models and technologies to study tau oligomerization represent important resources and avenues to push the forefront of elucidating the true toxic tau species. In this review, we will summarize the distinct tau oligomers generated using different strategies and discuss their conformational characteristics, neurotoxicity, relevance to pathological phenotypes, as well as their applications in drug discovery. This information will provide insights to understanding heterogeneous tau oligomers and their role as molecular targets for AD and related tauopathies.
{"title":"Heterogeneous Tau Oligomers as Molecular Targets for Alzheimer’s Disease and Related Tauopathies","authors":"Chih Hung Lo","doi":"10.3390/biophysica2040039","DOIUrl":"https://doi.org/10.3390/biophysica2040039","url":null,"abstract":"Tauopathies, including Alzheimer’s disease (AD), are a group of neurodegenerative disorders characterized by pathological aggregation of microtubule binding protein tau. The presence of tau neurofibrillary tangles, which are insoluble β-sheet fibrils, in the brain has been the histopathological hallmark of these diseases as their level correlates with the degree of cognitive impairment. However, recent studies suggest that tau oligomers, which are soluble proteins that are formed prior to insoluble fibrils, are the principal toxic species impairing neurons and inducing neurodegeneration. Targeting toxic tau oligomers is challenging, as they are mostly unstructured and adopting multiple conformations. The heterogeneity of tau oligomers is further illustrated by the different oligomeric species formed by various methods. The current models and technologies to study tau oligomerization represent important resources and avenues to push the forefront of elucidating the true toxic tau species. In this review, we will summarize the distinct tau oligomers generated using different strategies and discuss their conformational characteristics, neurotoxicity, relevance to pathological phenotypes, as well as their applications in drug discovery. This information will provide insights to understanding heterogeneous tau oligomers and their role as molecular targets for AD and related tauopathies.","PeriodicalId":72401,"journal":{"name":"Biophysica","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48141220","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-03DOI: 10.3390/biophysica2040037
M. Bleszynski
Various alternative compounds have been investigated to prevent icing, one of which includes poly(vinyl) alcohol (PVA), which has shown promising anti-freeze effects. However, determining the optimal structures and formulations of PVA for anti-icing applications has remained a challenge. Building upon our previous work, which used molecular dynamics simulations to assess the effects of hydroxyl group separation distance on ice nucleation, in this work, PVA was modified based upon the structures of antifreeze glycoproteins (AFGPs) found in Antarctic fish, and examined as a potential antifreeze compound. Four different PVA samples with different degrees of hydrolysis were fabricated and subsequently examined for their effects on ice crystallization. The results showed that the modified PVA samples with degrees of hydrolysis of 76% and 66% had an effect on ice crystallization, delaying ice crystallization by an average of approximately 20 min, and even preventing ice crystallization altogether in a small portion of the sample. Meanwhile, other samples with degrees of hydrolysis of 100% and 34% either showed no effect on ice crystallization, shortened the ice crystallization time, and appeared to promote ice nucleation.
{"title":"The Modification of Polyvinyl Alcohol for Ice Nucleation Based upon the Structures of Antifreeze Glycoproteins Found in Antarctic Fish","authors":"M. Bleszynski","doi":"10.3390/biophysica2040037","DOIUrl":"https://doi.org/10.3390/biophysica2040037","url":null,"abstract":"Various alternative compounds have been investigated to prevent icing, one of which includes poly(vinyl) alcohol (PVA), which has shown promising anti-freeze effects. However, determining the optimal structures and formulations of PVA for anti-icing applications has remained a challenge. Building upon our previous work, which used molecular dynamics simulations to assess the effects of hydroxyl group separation distance on ice nucleation, in this work, PVA was modified based upon the structures of antifreeze glycoproteins (AFGPs) found in Antarctic fish, and examined as a potential antifreeze compound. Four different PVA samples with different degrees of hydrolysis were fabricated and subsequently examined for their effects on ice crystallization. The results showed that the modified PVA samples with degrees of hydrolysis of 76% and 66% had an effect on ice crystallization, delaying ice crystallization by an average of approximately 20 min, and even preventing ice crystallization altogether in a small portion of the sample. Meanwhile, other samples with degrees of hydrolysis of 100% and 34% either showed no effect on ice crystallization, shortened the ice crystallization time, and appeared to promote ice nucleation.","PeriodicalId":72401,"journal":{"name":"Biophysica","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41829442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-01DOI: 10.3390/biophysica2040036
D. Prikule, V. Kukushkin, V. F. Prikuls
This study shows that the luminescent diagnostic of oral fluid allows the determination of the severity of inflammatory markers after implantation. The noninvasive diagnostic method, which is used, allows the rapid detection of the stages of development of the inflammatory process after intraosseous implantation and prevents the development of complications in the postoperative period.
{"title":"Noninvasive Digital Method for Determining Inflammation after Dental Implantation","authors":"D. Prikule, V. Kukushkin, V. F. Prikuls","doi":"10.3390/biophysica2040036","DOIUrl":"https://doi.org/10.3390/biophysica2040036","url":null,"abstract":"This study shows that the luminescent diagnostic of oral fluid allows the determination of the severity of inflammatory markers after implantation. The noninvasive diagnostic method, which is used, allows the rapid detection of the stages of development of the inflammatory process after intraosseous implantation and prevents the development of complications in the postoperative period.","PeriodicalId":72401,"journal":{"name":"Biophysica","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46327786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-28DOI: 10.3390/biophysica2040035
A. Sedigh, M. Akbarzadeh-T., R. Tomlinson
Bioprinting is an emerging tissue engineering method used to generate cell-laden scaffolds with high spatial resolution. Bioprinting parameters, such as pressure, nozzle size, and speed, highly influence the quality of the bioprinted construct. Moreover, cell suspension density and other critical biological parameters directly impact the biological function. Therefore, an approximation model that can be used to find the optimal bioprinting parameter settings for bioprinted constructs is highly desirable. Here, we propose a type-2 fuzzy model to handle the uncertainty and imprecision in the approximation model. Specifically, we focus on the biological parameters, such as the culture period, that can be used to maximize the output value (mineralization volume 21.8 mm3 with the same culture period of 21 days). We have also implemented a type-1 fuzzy model and compared the results with the proposed type-2 fuzzy model using two levels of uncertainty. We hypothesize that the type-2 fuzzy model may be preferred in biological systems due to the inherent vagueness and imprecision of the input data. Our numerical results confirm this hypothesis. More specifically, the type-2 fuzzy model with a high uncertainty boundary (30%) is superior to type-1 and type-2 fuzzy systems with low uncertainty boundaries in the overall output approximation error for bone bioprinting inputs.
{"title":"Optimizing Mineralization of Bioprinted Bone Utilizing Type-2 Fuzzy Systems","authors":"A. Sedigh, M. Akbarzadeh-T., R. Tomlinson","doi":"10.3390/biophysica2040035","DOIUrl":"https://doi.org/10.3390/biophysica2040035","url":null,"abstract":"Bioprinting is an emerging tissue engineering method used to generate cell-laden scaffolds with high spatial resolution. Bioprinting parameters, such as pressure, nozzle size, and speed, highly influence the quality of the bioprinted construct. Moreover, cell suspension density and other critical biological parameters directly impact the biological function. Therefore, an approximation model that can be used to find the optimal bioprinting parameter settings for bioprinted constructs is highly desirable. Here, we propose a type-2 fuzzy model to handle the uncertainty and imprecision in the approximation model. Specifically, we focus on the biological parameters, such as the culture period, that can be used to maximize the output value (mineralization volume 21.8 mm3 with the same culture period of 21 days). We have also implemented a type-1 fuzzy model and compared the results with the proposed type-2 fuzzy model using two levels of uncertainty. We hypothesize that the type-2 fuzzy model may be preferred in biological systems due to the inherent vagueness and imprecision of the input data. Our numerical results confirm this hypothesis. More specifically, the type-2 fuzzy model with a high uncertainty boundary (30%) is superior to type-1 and type-2 fuzzy systems with low uncertainty boundaries in the overall output approximation error for bone bioprinting inputs.","PeriodicalId":72401,"journal":{"name":"Biophysica","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47000333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-27DOI: 10.3390/biophysica2040034
Ariadna Villanueva, Henry Secaira-Morocho, L. F. Seoane, E. Lázaro, S. Manrubia
Viral populations are large and highly heterogeneous. Despite the evolutionary relevance of such heterogeneity, statistical approaches to quantifying the extent to which viruses maintain a high genotypic and/or phenotypic diversity have been rarely pursued. Here, we address this issue by analyzing a nucleotide-to-protein sequence map through deep sequencing of populations of the Qβ phage adapted to high temperatures. Tens of thousands of different sequences corresponding to two fragments of the gene coding for the viral replicase were recovered. A diversity analysis of two independent populations consistently revealed that about 40% of the mutations identified caused changes in protein amino acids, leading to an almost complete exploration of the protein neighborhood of (non-silent) mutants at a distance of one. The functional form of the empirical distribution of phenotype abundance agreed with analytical calculations that assumed random mutations in the nucleotide sequence. Our results concur with the idea that viral populations maintain a high diversity as an efficient adaptive mechanism and support the hypothesis of universality for a lognormal distribution of phenotype abundances in biologically meaningful genotype–phenotype maps, highlighting the relevance of entropic effects in molecular evolution.
{"title":"Genotype-to-Protein Map and Collective Adaptation in a Viral Population","authors":"Ariadna Villanueva, Henry Secaira-Morocho, L. F. Seoane, E. Lázaro, S. Manrubia","doi":"10.3390/biophysica2040034","DOIUrl":"https://doi.org/10.3390/biophysica2040034","url":null,"abstract":"Viral populations are large and highly heterogeneous. Despite the evolutionary relevance of such heterogeneity, statistical approaches to quantifying the extent to which viruses maintain a high genotypic and/or phenotypic diversity have been rarely pursued. Here, we address this issue by analyzing a nucleotide-to-protein sequence map through deep sequencing of populations of the Qβ phage adapted to high temperatures. Tens of thousands of different sequences corresponding to two fragments of the gene coding for the viral replicase were recovered. A diversity analysis of two independent populations consistently revealed that about 40% of the mutations identified caused changes in protein amino acids, leading to an almost complete exploration of the protein neighborhood of (non-silent) mutants at a distance of one. The functional form of the empirical distribution of phenotype abundance agreed with analytical calculations that assumed random mutations in the nucleotide sequence. Our results concur with the idea that viral populations maintain a high diversity as an efficient adaptive mechanism and support the hypothesis of universality for a lognormal distribution of phenotype abundances in biologically meaningful genotype–phenotype maps, highlighting the relevance of entropic effects in molecular evolution.","PeriodicalId":72401,"journal":{"name":"Biophysica","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45362310","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-26DOI: 10.3390/biophysica2040033
P. Serwer, E. Wright
Chemotherapy-inhibiting tumor cell evolution to drug-resistance is potentially suppressed by using a drug delivery vehicle (DDV) that has gating. Gating would be used to increase tumor-selectivity of delivery of DDV packaged drug. Tumor-selectivity increase would make possible increase in tumor-delivered drug dose, which would suppress opportunities to evolve drug resistance. Currently used DDVs do not have gating but gating is a natural feature of some bacteriophages (phages). Phage T4, which has recently been found highly persistent in murine blood, is a potential gated DDV. Thus, here, we proceed towards a T4-DDV by developing (1) improved procedure for generating high concentrations and amounts of phage T4, (2) elevated temperature-driven gate-opening and ethidium- and bleomycin-loading, and (3) purification of loaded T4 by rate zonal centrifugation. We test for loading by native agarose gel electrophoresis (AGE) with fluorescence detection. We observe loading in both phage T4 and T4 (tail-free) heads. The loaded particles have an openable, closed gate. Stored, mature T4 phages and phage heads do not release ethidium during at least a month at 4 °C and 6 days at 37 and 42 °C. Tumor-specific T4 phage delivery is projected via both the EPR effect and high T4 persistence.
{"title":"Gated Ethidium- and Bleomycin-Loading in Phage T4 That Is Subsequently Purified Leak-Free","authors":"P. Serwer, E. Wright","doi":"10.3390/biophysica2040033","DOIUrl":"https://doi.org/10.3390/biophysica2040033","url":null,"abstract":"Chemotherapy-inhibiting tumor cell evolution to drug-resistance is potentially suppressed by using a drug delivery vehicle (DDV) that has gating. Gating would be used to increase tumor-selectivity of delivery of DDV packaged drug. Tumor-selectivity increase would make possible increase in tumor-delivered drug dose, which would suppress opportunities to evolve drug resistance. Currently used DDVs do not have gating but gating is a natural feature of some bacteriophages (phages). Phage T4, which has recently been found highly persistent in murine blood, is a potential gated DDV. Thus, here, we proceed towards a T4-DDV by developing (1) improved procedure for generating high concentrations and amounts of phage T4, (2) elevated temperature-driven gate-opening and ethidium- and bleomycin-loading, and (3) purification of loaded T4 by rate zonal centrifugation. We test for loading by native agarose gel electrophoresis (AGE) with fluorescence detection. We observe loading in both phage T4 and T4 (tail-free) heads. The loaded particles have an openable, closed gate. Stored, mature T4 phages and phage heads do not release ethidium during at least a month at 4 °C and 6 days at 37 and 42 °C. Tumor-specific T4 phage delivery is projected via both the EPR effect and high T4 persistence.","PeriodicalId":72401,"journal":{"name":"Biophysica","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47810379","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}