Introduction of Surface Loops as a Tool for Encapsulin Functionalization.

Encapsulin based protein cages are nanoparticles with different biomedical applications, such as targeted drug delivery or imaging agents. These particles are biocompatible and can be produced in bacteria, allowing large scale production and protein engineering. In order to use these bacterial nanocages in different applications, it is important to further explore the potential of their surface modification and optimize their production. In this study we design and show new surface modifications of the Thermotoga maritima (Tm) and Brevibacterium linens (Bl) encapsulins. Two new loops on Tm encapsulin with a His-tag insertion after the residue 64 and the residue 127, and the modification of the C-terminal on Bl encapsulin, are reported. The multi-modification of the Tm encapsulin enables up to 240 different functionalities on the cage surface, resulting from 4 potential modifications per protein subunit. We furthermore report an improved protocol giving a better stability and providing a notable increase of the production yield of the cages. Finally, we tested the stability of different encapsulin variants over a year and the results show a difference in stability arising from the tag insertion position. These first insights in the structure-property relationship of encapsulins, with respect to the position of a function loop, allow for further study of the use of these protein nanocages in biomedical applications.

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Cyanobacteria—From the Oceans to the Potential Biotechnological and Biomedical Applications

Marine Drugs ◽

10.3390/md19050241 ◽

2021 ◽

Vol 19 (5) ◽

pp. 241

Author(s):

Shaden A. M. Khalifa ◽

Eslam S. Shedid ◽

Essa M. Saied ◽

Amir Reza Jassbi ◽

Fatemeh H. Jamebozorgi ◽

...

Keyword(s):

Bioactive Compounds ◽

Biomedical Applications ◽

Large Scale ◽

Biological Activities ◽

Scale Production ◽

Pharmacological Activities ◽

Large Scale Production ◽

Marine Products ◽

Hiv 1 ◽

Successful Phase

Cyanobacteria are photosynthetic prokaryotic organisms which represent a significant source of novel, bioactive, secondary metabolites, and they are also considered an abundant source of bioactive compounds/drugs, such as dolastatin, cryptophycin 1, curacin toyocamycin, phytoalexin, cyanovirin-N and phycocyanin. Some of these compounds have displayed promising results in successful Phase I, II, III and IV clinical trials. Additionally, the cyanobacterial compounds applied to medical research have demonstrated an exciting future with great potential to be developed into new medicines. Most of these compounds have exhibited strong pharmacological activities, including neurotoxicity, cytotoxicity and antiviral activity against HCMV, HSV-1, HHV-6 and HIV-1, so these metabolites could be promising candidates for COVID-19 treatment. Therefore, the effective large-scale production of natural marine products through synthesis is important for resolving the existing issues associated with chemical isolation, including small yields, and may be necessary to better investigate their biological activities. Herein, we highlight the total synthesized and stereochemical determinations of the cyanobacterial bioactive compounds. Furthermore, this review primarily focuses on the biotechnological applications of cyanobacteria, including applications as cosmetics, food supplements, and the nanobiotechnological applications of cyanobacterial bioactive compounds in potential medicinal applications for various human diseases are discussed.

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(Invited) Improve Electrodes' Electrochemical Performance for HER and OER By Hydrogenation Treatment

ECS Meeting Abstracts ◽

10.1149/ma2018-01/31/1840 ◽

2018 ◽

Vol MA2018-01 (31) ◽

pp. 1840-1840

Author(s):

Xiaobo Chen

Keyword(s):

Hydrogen Production ◽

Large Scale ◽

Electrode Materials ◽

Scale Production ◽

Structure Property ◽

Large Scale Production ◽

Property Performance ◽

Splitting Process ◽

New Discovery ◽

Hydrogenation Treatment

Hydrogen production through electrolysis has been regarded as one of the most promising solutions for large-scale production of clean fuels. However, most electrodes have large overpotentials in the HER and OER reactions during the water splitting process. Many approaches and methods have been developed to enhance the electrodes' performance. Here, we would like to present our studies on the hydrogenation of various electrode materials for HER and OER applications. We aim to reveal the structure-property-performance relationship for those electrodes after hydrogenation treatment. We wish our work could provide useful information and will be honored if our work can inspire new discovery and finding in the related fields to advance our understanding and technologies for efficient hydrogen production through electrolysis.

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Vibrio Proteases for Biomedical Applications: Modulating the Proteolytic Secretome of V. alginolyticus and V. parahaemolyticus for Improved Enzymes Production

Microorganisms ◽

10.3390/microorganisms7100387 ◽

2019 ◽

Vol 7 (10) ◽

pp. 387 ◽

Cited By ~ 2

Author(s):

Monica Salamone ◽

Aldo Nicosia ◽

Giulio Ghersi ◽

Marcello Tagliavia

Keyword(s):

Vibrio Parahaemolyticus ◽

Biomedical Applications ◽

Large Scale ◽

Proteolytic Enzymes ◽

High Specificity ◽

Growth Conditions ◽

Culture Conditions ◽

Scale Production ◽

Biological Responses ◽

Large Scale Production

Proteolytic enzymes are of great interest for biotechnological purposes, and their large-scale production, as well as the discovery of strains producing new molecules, is a relevant issue. Collagenases are employed for biomedical and pharmaceutical purposes. The high specificity of collagenase-based preparations toward the substrate strongly relies on the enzyme purity. However, the overall activity may depend on the cooperation with other proteases, the presence of which may be essential for the overall enzymatic activity, but potentially harmful for cells and tissues. Vibrios produce some of the most promising bacterial proteases (including collagenases), and their exo-proteome includes several enzymes with different substrate specificities, the production and relative abundances of which strongly depend on growth conditions. We evaluated the effects of different media compositions on the proteolytic exo-proteome of Vibrio alginolyticus and its closely relative Vibrio parahaemolyticus, in order to improve the overall proteases production, as well as the yield of the desired enzymes subset. Substantial biological responses were achieved with all media, which allowed defining culture conditions for targeted improvement of selected enzyme classes, besides giving insights in possible regulatory mechanisms. In particular, we focused our efforts on collagenases production, because of the growing biotechnological interest due to their pharmaceutical/biomedical applications.

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300-Fold Increase in Production of the Zn2+-Dependent Dechlorinase TrzN in Soluble Form via Apoenzyme Stabilization

Applied and Environmental Microbiology ◽

10.1128/aem.00916-14 ◽

2014 ◽

Vol 80 (13) ◽

pp. 4003-4011 ◽

Cited By ~ 9

Author(s):

Colin J. Jackson ◽

Christopher W. Coppin ◽

Paul D. Carr ◽

Alexey Aleksandrov ◽

Matthew Wilding ◽

...

Keyword(s):

Soluble Protein ◽

Metal Ion ◽

Large Scale ◽

Computational Simulation ◽

Active Form ◽

Fold Increase ◽

Soluble Form ◽

Scale Production ◽

Content Type ◽

The Stability

ABSTRACTMicrobial metalloenzymes constitute a large library of biocatalysts, a number of which have already been shown to catalyze the breakdown of toxic chemicals or industrially relevant chemical transformations. However, while there is considerable interest in harnessing these catalysts for biotechnology, for many of the enzymes, their large-scale production in active, soluble form in recombinant systems is a significant barrier to their use. In this work, we demonstrate that as few as three mutations can result in a 300-fold increase in the expression of soluble TrzN, an enzyme fromArthrobacter aurescenswith environmental applications that catalyzes the hydrolysis of triazine herbicides, inEscherichia coli. Using a combination of X-ray crystallography, kinetic analysis, and computational simulation, we show that the majority of the improvement in expression is due to stabilization of the apoenzyme rather than the metal ion-bound holoenzyme. This provides a structural and mechanistic explanation for the observation that many compensatory mutations can increase levels of soluble-protein production without increasing the stability of the final, active form of the enzyme. This study provides a molecular understanding of the importance of the stability of metal ion free states to the accumulation of soluble protein and shows that differences between apoenzyme and holoenzyme structures can result in mutations affecting the stability of either state differently.

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Microbial-Physical Synthesis of Fe and Fe3O4 Magnetic Nanoparticles Using Aspergillus niger YESM1 and Supercritical Condition of Ethanol

Journal of Nanomaterials ◽

10.1155/2016/9174891 ◽

2016 ◽

Vol 2016 ◽

pp. 1-7 ◽

Cited By ~ 23

Author(s):

Mai Abdeen ◽

Soraya Sabry ◽

Hanan Ghozlan ◽

Ahmed A. El-Gendy ◽

Everett E. Carpenter

Keyword(s):

Magnetic Nanoparticles ◽

Aspergillus Niger ◽

Biomedical Applications ◽

Large Scale ◽

Crystal Size ◽

Supercritical Condition ◽

Scale Production ◽

Large Scale Production ◽

Average Size ◽

Biophysical Method

Magnetic Fe and Fe3O4 (magnetite) nanoparticles are successfully synthesized using Aspergillus niger YESM 1 and supercritical condition of liquids. Aspergillus niger is used for decomposition of FeSO4 and FeCl3 to FeS and Fe2O3, respectively. The produced particles are exposed to supercritical condition of ethanol for 1 hour at 300°C and pressure of 850 psi. The phase structure and the morphology measurements yield pure iron and major Fe3O4 spherical nanoparticles with average size of 18 and 50 nm, respectively. The crystal size amounts to 9 nm for Fe and 8 nm for Fe3O4. The magnetic properties are measured to exhibit superparamagnetic- and ferromagnetic-like behaviors for Fe and Fe3O4 nanoparticles, respectively. The saturation magnetization amounts to 112 and 68 emu/g for Fe and Fe3O4, respectively. The obtained results open new route for using the biophysical method for large-scale production of highly magnetic nanoparticles to be used for biomedical applications.

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Call for papers on special issue “Perovskite photovoltaics and optoelectronic devices”

Materials International ◽

10.33263/materials21.049049 ◽

2020 ◽

Vol 2 (1) ◽

pp. 049-049

Keyword(s):

Solar Cells ◽

Large Scale ◽

Perovskite Solar Cells ◽

Optoelectronic Devices ◽

Scale Production ◽

Special Issue ◽

Device Structure ◽

Stability Performance ◽

Large Scale Production ◽

The Stability

Aim & Scope: Metal halide perovskitehave been regarded as promising classes of materials for photovoltaics and optoelectronic devices, owing to the unique characteristics, such as long charge carrier diffusion lengths, precise tunable bandgaps, high light absorption coefficients, and high defect tolerance. Research on perovskite in the fields including photovoltaics, light-emitting diodes, lasers, X-ray imaging, and photodetectors has been gaining increasingly interest over the past years. Up to now, the efficiency of perovskite solar cells has grown from 3.8% in single-junction solar cells in 2009 to more than 25%, catching up the efficiency level of commercial silicon cells. Up to now, the key issues of perovskite photovoltaics and optoelectronic devices have become the stability, performance and large-scale production. This requires optimization of the film morphology, interface, device structure and the fabrication process. A lot work has been done on this issue and has made remarkable progress. We kindly invite you to submit a manuscript(s) for this Special Issue. Full papers, communications, and reviews are all welcome.

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Heterologous Expression, Characterization and Evolution Prediction of a Diaphorase From Geobacillus sp. Y4.1MC1

10.21203/rs.3.rs-793569/v1 ◽

2021 ◽

Author(s):

Jinzhao Shang ◽

Shuohao Yue ◽

Fang Zeng ◽

Yun Chen ◽

Longgang Jia

Keyword(s):

Large Scale ◽

Ketone Bodies ◽

Scale Production ◽

Hydroxybutyric Acid ◽

E Coli ◽

Ph Values ◽

Structure Changes ◽

Large Scale Production ◽

Expression Characterization ◽

The Stability

Abstract β-hydroxybutyric acid is the most sensitive indicator in ketoacidosis detection, and accounts for nearly 78% of the ketone bodies. Diaphorase is commonly used to detect the β-hydroxybutyric acid in clinical diagnosis. However, the extraction of diaphorase from animal myocardium is complex and low-yield, which is not convenient for large-scale production. In this study, a diaphorase from Geobacillus sp. Y4.1MC1 was efficiently heterologous expressed and purified in E. coli a yield of 110 mg/L culture. The optimal temperature and pH of this recombinant diaphorase (rDIA) were 55 °C and 6.5, respectively. It was proved that rDIA was a dual acid- and thermo-stable enzyme, and which showed much more accurate detection of β-hydroxybutyric acid than the commercial enzyme. Additionally, we also investigated the molecular interaction of rDIA with the substrate, and the conformation transition in different pH values by using homology modeling and molecular dynamics (MD) simulation. The results showed that 141-161 domain of rDIA played important role in the structure changes and conformations transmission at different pH values. Moreover, it was predicted that F105W, F105R and M186R mutants were able to improve the binding affinity of rDIA, and A2Y, P35F, Q36D, N210L, F211Y mutants were benefit for the stability of rDIA.

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Production of isomelezitose from sucrose by engineered glucansucrases

Amylase ◽

10.1515/amylase-2017-0008 ◽

2017 ◽

Vol 1 (1) ◽

Cited By ~ 3

Author(s):

Gregory L. Côté ◽

Christopher A. Dunlap ◽

Karl E. Vermillion ◽

Christopher D. Skory

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Biomedical Applications ◽

Large Scale ◽

Single Point ◽

Single Point Mutation ◽

Scale Production ◽

Acceptor Substrate ◽

Large Scale Production ◽

High Yields

AbstractCertain lactic acid bacteria produce glycosyltransferases known as glucansucrases, which synthesize α-D-glucans via glucosyl transfer from sucrose. We recently reported on the formation of the unusual trisaccharide isomelezitose in low yields by a variety of glucansucrases. Isomelezitose is a rare non-reducing trisaccharide, with the structure α-d-glucopyranosyl- (1→6)-β-d-fructofuranosyl-(2↔1)-α-d-glucopyranoside. In this work, we describe the synthesis of isomelezitose in high yields by variants of glucansucrases engineered to contain a single point mutation at a key leucine residue involved in acceptor substrate binding. Some variants produce isomelezitose in yields up to 57%. This method is amenable to large-scale production of isomelezitose for food, industrial and biomedical applications.

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Origins of stereoselectivity in evolved ketoreductases

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1507910112 ◽

2015 ◽

Vol 112 (51) ◽

pp. E7065-E7072 ◽

Cited By ~ 50

Author(s):

Elizabeth L. Noey ◽

Nidhi Tibrewal ◽

Gonzalo Jiménez-Osés ◽

Sílvia Osuna ◽

Jiyong Park ◽

...

Keyword(s):

Conformational Changes ◽

Large Scale ◽

Kinetic Studies ◽

Md Simulations ◽

Binding Pocket ◽

Scale Production ◽

Large Scale Production ◽

Conformational Preferences ◽

Short Chain Alcohol ◽

The Stability

Mutants of Lactobacillus kefir short-chain alcohol dehydrogenase, used here as ketoreductases (KREDs), enantioselectively reduce the pharmaceutically relevant substrates 3-thiacyclopentanone and 3-oxacyclopentanone. These substrates differ by only the heteroatom (S or O) in the ring, but the KRED mutants reduce them with different enantioselectivities. Kinetic studies show that these enzymes are more efficient with 3-thiacyclopentanone than with 3-oxacyclopentanone. X-ray crystal structures of apo- and NADP+-bound selected mutants show that the substrate-binding loop conformational preferences are modified by these mutations. Quantum mechanical calculations and molecular dynamics (MD) simulations are used to investigate the mechanism of reduction by the enzyme. We have developed an MD-based method for studying the diastereomeric transition state complexes and rationalize different enantiomeric ratios. This method, which probes the stability of the catalytic arrangement within the theozyme, shows a correlation between the relative fractions of catalytically competent poses for the enantiomeric reductions and the experimental enantiomeric ratio. Some mutations, such as A94F and Y190F, induce conformational changes in the active site that enlarge the small binding pocket, facilitating accommodation of the larger S atom in this region and enhancing S-selectivity with 3-thiacyclopentanone. In contrast, in the E145S mutant and the final variant evolved for large-scale production of the intermediate for the antibiotic sulopenem, R-selectivity is promoted by shrinking the small binding pocket, thereby destabilizing the pro-S orientation.

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Fluorescent carbon dots as prospective nanoagents for imaging-assisted biomedical applications

Current Medicinal Chemistry ◽

10.2174/0929867328666211129121958 ◽

2021 ◽

Vol 28 ◽

Author(s):

Le Minh Tu Phan

Keyword(s):

Carbon Dots ◽

Biomedical Applications ◽

Large Scale ◽

Low Cost ◽

Scale Production ◽

Large Scale Production ◽

Intense Exploitation ◽

Fluorescent Carbon Dots

: Carbon dots (CDs), an emerging nanoagent providing an alternative to conventional fluorescent agents, are sparking the scientist’s interest in biomedical applications owing to their unique advantages, including ease of synthesis, large scale production, low cost, prominent photoluminescence, good photostability, easy functionalization, sufficient biocompatibility, good nanocarrier, and excellent ability to generate reactive oxygen species or heat. Herein, this perspective provides a viewpoint about imaging-assisted biomedical applications using fluorescent CDs regarding in vitro and in vivo bioimaging, imaging-assisted sensing, and imaging-guided therapy. The opinions about their potential and challenges in applicable biomedical applications are discussed to develop, further ameliorated CDs for their intense exploitation in diverse imaging-assisted biomedical applications.

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