Class A -Lactamases as Versatile Scaffolds to Create Hybrid Enzymes: Applications from Basic Research to Medicine

Designing hybrid proteins is a major aspect of protein engineering and covers a very wide range of applications from basic research to medical applications. This review focuses on the use of class Aβ-lactamases as versatile scaffolds to design hybrid enzymes (referred to asβ-lactamase hybrid proteins, BHPs) in which an exogenous peptide, protein or fragment thereof is inserted at various permissive positions. We discuss how BHPs can be specifically designed to create bifunctional proteins, to produce and to characterize proteins that are otherwise difficult to express, to determine the epitope of specific antibodies, to generate antibodies against nonimmunogenic epitopes, and to better understand the structure/function relationship of proteins.

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Structure–property–function relationship of fluorescent conjugated microporous polymers

Materials Chemistry Frontiers ◽

10.1039/d0qm00769b ◽

2021 ◽

Author(s):

M. G. Monika Bai ◽

H. Vignesh Babu ◽

V. Lakshmi ◽

M. Rajeswara Rao

Keyword(s):

Long Range ◽

Structure Property ◽

Porous Organic Polymers ◽

Aggregation Induced Emission ◽

Microporous Polymers ◽

Exciton Migration ◽

Wide Range ◽

Function Relationship ◽

Relationship Of ◽

Conjugated Microporous Polymers

Fluorescent porous organic polymers are a unique class of materials owing to their strong aggregation induced emission, long range exciton migration and permanent porosity, thus envisioned to possess a wide range of applications (sensing, OLEDs).

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The Role of the Fibronectin IGD Motif in Stimulating Fibroblast Migration

Journal of Biological Chemistry ◽

10.1074/jbc.m707532200 ◽

2007 ◽

Vol 282 (49) ◽

pp. 35530-35535 ◽

Cited By ~ 27

Author(s):

Christopher J. Millard ◽

Ian R. Ellis ◽

Andrew R. Pickford ◽

Ana M. Schor ◽

Seth L. Schor ◽

...

Keyword(s):

Fibroblast Migration ◽

Wide Range ◽

Migration Stimulating Factor ◽

Function Relationship ◽

Relationship Of ◽

Stimulating Factor ◽

Insight Into ◽

Stimulation Of

The motogenic activity of migration-stimulating factor, a truncated isoform of fibronectin (FN), has been attributed to the IGD motifs present in its FN type 1 modules. The structure-function relationship of various recombinant IGD-containing FN fragments is now investigated. Their structure is assessed by solution state NMR and their motogenic ability tested on fibroblasts. Even conservative mutations in the IGD motif are inactive or have severely reduced potency, while the structure remains essentially the same. A fragment with two IGD motifs is 100 times more active than a fragment with one and up to 106 times more than synthetic tetrapeptides. The wide range of potency in different contexts is discussed in terms of cryptic FN sites and cooperativity. These results give new insight into the stimulation of fibroblast migration by IGD motifs in FN.

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New multiscale characterisation methodology for effective determination of isolation-structure-function relationship of extracellular vesicles

10.1101/2021.02.09.430523 ◽

2021 ◽

Author(s):

Thanh Huyen Phan ◽

Shiva Kamini Divakarla ◽

Jia Hao Yeo ◽

Qingyu Lei ◽

Priyanka Tharkar ◽

...

Keyword(s):

Extracellular Vesicles ◽

Biological Effects ◽

Dry Mass ◽

Experimental Methodology ◽

Wide Range ◽

Isolation Methods ◽

Function Relationship ◽

Relationship Of

AbstractExtracellular vesicles (EVs) have been lauded as next generation medicines, but very few EV-based therapeutics have progressed to clinical use. Limited clinical translation is largely due to technical barriers that hamper our ability to mass-produce EVs, i.e. to isolate, purify and characterise them effectively. Technical limitations in comprehensive characterisation of EVs leads to unpredicted biological effects of EVs. Here, using a range of optical and non-optical techniques, we showed that the differences in molecular composition of EVs isolated using two isolation methods correlated with the differences in their biological function. Our results demonstrated that the isolation method determines the composition of isolated EVs at single and sub-population levels. Besides the composition, we measured for the first time the dry mass and predicted sedimentation of EVs. These parameters were shown to correlate well with the biological and functional effects of EVs on single cell and cell cultures. We anticipate that our new multiscale characterisation approach, which goes beyond traditional experimental methodology, will support fundamental understanding of EVs as well as elucidate the functional effects of EVs in in vitro and in vivo studies. Our findings and methodology will be pivotal for developing optimal isolation methods and establishing EVs as mainstream therapeutics and diagnostics. This innovative approach is applicable to a wide range of sectors including biopharma and biotechnology as well as to regulatory agencies.

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Analysis of the structure/function relationship of Cobra Venom Factor (CVF) and C3: Generation of CVF/cobra-C3 hybrid proteins

Immunopharmacology ◽

10.1016/s0162-3109(00)80281-7 ◽

2000 ◽

Vol 49 (1-2) ◽

pp. 94 ◽

Cited By ~ 9

Author(s):

Daniel Wehrhahn ◽

Kim M. Meiling ◽

David C. Fritzinger ◽

Reinhard Bredehorst ◽

Jörg Andrä ◽

...

Keyword(s):

Structure Function ◽

Cobra Venom ◽

Cobra Venom Factor ◽

Hybrid Proteins ◽

Structure Function Relationship ◽

Function Relationship ◽

Relationship Of

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Crystal structure of jumping spider rhodopsin-1 as a light sensitive GPCR

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1902192116 ◽

2019 ◽

Vol 116 (29) ◽

pp. 14547-14556 ◽

Cited By ~ 10

Author(s):

Niranjan Varma ◽

Eshita Mutt ◽

Jonas Mühle ◽

Valérie Panneels ◽

Akihisa Terakita ◽

...

Keyword(s):

Crystal Structure ◽

Conformational Changes ◽

Jumping Spider ◽

Downstream Signaling ◽

Class A ◽

Bovine Rhodopsin ◽

Function Relationship ◽

Relationship Of ◽

G Protein Coupled

Light-sensitive G protein-coupled receptors (GPCRs)—rhodopsins—absorb photons to isomerize their covalently bound retinal, triggering conformational changes that result in downstream signaling cascades. Monostable rhodopsins release retinal upon isomerization as opposed to the retinal in bistable rhodopsins that “reisomerize” upon absorption of a second photon. Understanding the mechanistic differences between these light-sensitive GPCRs has been hindered by the scarcity of recombinant models of the latter. Here, we reveal the high-resolution crystal structure of a recombinant bistable rhodopsin, jumping spider rhodopsin-1, bound to the inverse agonist 9-cis retinal. We observe a water-mediated network around the ligand hinting toward the basis of their bistable nature. In contrast to bovine rhodopsin (monostable), the transmembrane bundle of jumping spider rhodopsin-1 as well that of the bistable squid rhodopsin adopts a more “activation-ready” conformation often observed in other nonphotosensitive class A GPCRs. These similarities suggest the role of jumping spider rhodopsin-1 as a potential model system in the study of the structure–function relationship of both photosensitive and nonphotosensitive class A GPCRs.

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New Multiscale Characterization Methodology for Effective Determination of Isolation–Structure–Function Relationship of Extracellular Vesicles

Frontiers in Bioengineering and Biotechnology ◽

10.3389/fbioe.2021.669537 ◽

2021 ◽

Vol 9 ◽

Author(s):

Thanh Huyen Phan ◽

Shiva Kamini Divakarla ◽

Jia Hao Yeo ◽

Qingyu Lei ◽

Priyanka Tharkar ◽

...

Keyword(s):

Extracellular Vesicles ◽

Biological Effects ◽

Dry Mass ◽

Experimental Methodology ◽

Wide Range ◽

Isolation Methods ◽

Function Relationship ◽

Relationship Of

Extracellular vesicles (EVs) have been lauded as next-generation medicines, but very few EV-based therapeutics have progressed to clinical use. Limited clinical translation is largely due to technical barriers that hamper our ability to mass produce EVs, i.e., to isolate, purify, and characterize them effectively. Technical limitations in comprehensive characterization of EVs lead to unpredicted biological effects of EVs. Here, using a range of optical and non-optical techniques, we showed that the differences in molecular composition of EVs isolated using two isolation methods correlated with the differences in their biological function. Our results demonstrated that the isolation method determines the composition of isolated EVs at single and sub-population levels. Besides the composition, we measured for the first time the dry mass and predicted sedimentation of EVs. These parameters were likely to contribute to the biological and functional effects of EVs on single cell and cell cultures. We anticipate that our new multiscale characterization approach, which goes beyond traditional experimental methodology, will support fundamental understanding of EVs as well as elucidate the functional effects of EVs in in vitro and in vivo studies. Our findings and methodology will be pivotal for developing optimal isolation methods and establishing EVs as mainstream therapeutics and diagnostics. This innovative approach is applicable to a wide range of sectors including biopharma and biotechnology as well as to regulatory agencies.

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Antineoplastic Activity, Structural Modification, Synthesis and Structure-activity Relationship of Dammarane-type Ginsenosides: An Overview

Current Organic Chemistry ◽

10.2174/1385272823666190401141138 ◽

2019 ◽

Vol 23 (5) ◽

pp. 503-516 ◽

Cited By ~ 1

Author(s):

Qiang Zhang ◽

Xude Wang ◽

Liyan Lv ◽

Guangyue Su ◽

Yuqing Zhao

Keyword(s):

Structural Modification ◽

Gastrointestinal Disease ◽

Structure Activity Relationship ◽

Cerebrovascular Diseases ◽

Activity Relationship ◽

Cycle Arrest ◽

Structure Activity ◽

Wide Range ◽

Structural Association ◽

Relationship Of

Dammarane-type ginsenosides are a class of tetracyclic triterpenoids with the same dammarane skeleton. These compounds have a wide range of pharmaceutical applications for neoplasms, diabetes mellitus and other metabolic syndromes, hyperlipidemia, cardiovascular and cerebrovascular diseases, aging, neurodegenerative disease, bone disease, liver disease, kidney disease, gastrointestinal disease and other conditions. In order to develop new antineoplastic drugs, it is necessary to improve the bioactivity, solubility and bioavailability, and illuminate the mechanism of action of these compounds. A large number of ginsenosides and their derivatives have been separated from certain herbs or synthesized, and tested in various experiments, such as anti-proliferation, induction of apoptosis, cell cycle arrest and cancer-involved signaling pathways. In this review, we have summarized the progress in structural modification, shed light on the structure-activity relationship (SAR), and offered insights into biosynthesis-structural association. This review is expected to provide a preliminary guide for the modification and synthesis of ginsenosides.

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Implementation of Power-Efficient Class AB Miller Amplifiers Using Resistive Local Common-Mode Feedback

Journal of Low Power Electronics and Applications ◽

10.3390/jlpea11030031 ◽

2021 ◽

Vol 11 (3) ◽

pp. 31

Author(s):

Anindita Paul ◽

Mario Renteria-Pinon ◽

Jaime Ramirez-Angulo ◽

Ricardo Bolaños-Pérez ◽

Héctor Vázquez-Leal ◽

...

Keyword(s):

Current Efficiency ◽

Figure Of Merit ◽

Small Signal ◽

Common Mode ◽

Power Efficient ◽

Class Ab ◽

Op Amp ◽

Class A ◽

Wide Range ◽

Quiescent Current

An approach to implement single-ended power-efficient static class-AB Miller op-amps with symmetrical and significantly enhanced slew-rate and accurately controlled output quiescent current is introduced. The proposed op-amp can drive a wide range of resistive and capacitive loads. The output positive and negative currents can be much higher than the total op-amp quiescent current. The enhanced performance is achieved by utilizing a simple low-power auxiliary amplifier with resistive local common-mode feedback that increases the quiescent power dissipation by less than 10%. The proposed class AB op-amp is characterized by significantly enhanced large-signal dynamic, static current efficiency, and small-signal figures of merits. The dynamic current efficiency is 15.6 higher, the static current efficiency is 8.9 times higher, and the small-signal figure of merit is 2.3 times higher than the conventional class-A op-amp. A global figure of merit that determines an op-amp’s ultimate speed is 6.33 times higher than the conventional class A op-amp.

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Advanced Functional Materials Based on Nanocellulose for Pharmaceutical/Medical Applications

Pharmaceutics ◽

10.3390/pharmaceutics13081125 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1125

Author(s):

Raluca Nicu ◽

Florin Ciolacu ◽

Diana E. Ciolacu

Keyword(s):

Rapid Development ◽

Cellulose Nanofibrils ◽

Functional Materials ◽

Medical Applications ◽

Bacterial Nanocellulose ◽

Green Materials ◽

Wide Range ◽

In Vivo Cytotoxicity

Nanocelluloses (NCs), with their remarkable characteristics, have proven to be one of the most promising “green” materials of our times and have received special attention from researchers in nanomaterials. A diversity of new functional materials with a wide range of biomedical applications has been designed based on the most desirable properties of NCs, such as biocompatibility, biodegradability, and their special physicochemical properties. In this context and under the pressure of rapid development of this field, it is imperative to synthesize the successes and the new requirements in a comprehensive review. The first part of this work provides a brief review of the characteristics of the NCs (cellulose nanocrystals—CNC, cellulose nanofibrils—CNF, and bacterial nanocellulose—BNC), as well as of the main functional materials based on NCs (hydrogels, nanogels, and nanocomposites). The second part presents an extensive review of research over the past five years on promising pharmaceutical and medical applications of nanocellulose-based materials, which have been discussed in three important areas: drug-delivery systems, materials for wound-healing applications, as well as tissue engineering. Finally, an in-depth assessment of the in vitro and in vivo cytotoxicity of NCs-based materials, as well as the challenges related to their biodegradability, is performed.

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Role of Insulin in Health and Disease: An Update

International Journal of Molecular Sciences ◽

10.3390/ijms22126403 ◽

2021 ◽

Vol 22 (12) ◽

pp. 6403

Author(s):

Md Saidur Rahman ◽

Khandkar Shaharina Hossain ◽

Sharnali Das ◽

Sushmita Kundu ◽

Elikanah Olusayo Adegoke ◽

...

Keyword(s):

Insulin Signaling ◽

Basic Research ◽

Future Research ◽

Protective Effects ◽

Glucose Levels ◽

Physiological Processes ◽

Blood Glucose Levels ◽

Wide Range ◽

Health And Disease

Insulin is a polypeptide hormone mainly secreted by β cells in the islets of Langerhans of the pancreas. The hormone potentially coordinates with glucagon to modulate blood glucose levels; insulin acts via an anabolic pathway, while glucagon performs catabolic functions. Insulin regulates glucose levels in the bloodstream and induces glucose storage in the liver, muscles, and adipose tissue, resulting in overall weight gain. The modulation of a wide range of physiological processes by insulin makes its synthesis and levels critical in the onset and progression of several chronic diseases. Although clinical and basic research has made significant progress in understanding the role of insulin in several pathophysiological processes, many aspects of these functions have yet to be elucidated. This review provides an update on insulin secretion and regulation, and its physiological roles and functions in different organs and cells, and implications to overall health. We cast light on recent advances in insulin-signaling targeted therapies, the protective effects of insulin signaling activators against disease, and recommendations and directions for future research.

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