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Brahma D, Sarangi AN, Kaushik R, Gupta AN. Oxidative stress induced conformational changes of human serum albumin. Phys Chem Chem Phys 2024; 26:8528-8538. [PMID: 38411624 DOI: 10.1039/d4cp00059e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2024]
Abstract
Oxidative stress, generated by reactive oxygen species (ROS), is responsible for the loss of structure and functionality of proteins and is associated with several aging-related diseases. Here, we report an in vitro study to gauge the effect of ROS on the structural rearrangement of human serum albumin (HSA), a plasma protein, through metal-catalyzed oxidation (MCO) at physiological temperature through various biophysical techniques like UV-vis absorption, circular dichroism (CD), differential scanning calorimetry (DSC), MALDI-TOF, FTIR, and Raman spectroscopy. The UV-vis spectra of oxidized HSA show an early blueshift, signifying the unfolding of the protein because of ROS followed by the broadening of the absorption peak at a longer time. The DSC data corroborate the observation, revealing an exothermic transition for the oxidized sample at a longer time, suggesting in situ aggregation. The CD and FTIR spectra indicate the associated secondary structural changes occurring with time, depicting the variation of the helical content of HSA. The amide-III analysis of Raman data also complements the structural changes, and MALDI-TOF data show the mass distribution with time. Overall, this work might help determine the effect of oxidation on the biological activity of serum albumin as it can impact the physiological properties of HSA.
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Affiliation(s)
- Debdip Brahma
- Biophysics and Soft Matter Laboratory, Department of Physics, Indian Institute of Technology, Kharagpur, 721302, India.
| | - Akshay Narayan Sarangi
- Biophysics and Soft Matter Laboratory, Department of Physics, Indian Institute of Technology, Kharagpur, 721302, India.
| | - Rupal Kaushik
- Biophysics and Soft Matter Laboratory, Department of Physics, Indian Institute of Technology, Kharagpur, 721302, India.
| | - Amar Nath Gupta
- Biophysics and Soft Matter Laboratory, Department of Physics, Indian Institute of Technology, Kharagpur, 721302, India.
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2
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Brahma D, Sarkar T, Kaushik R, Sarangi AN, Gupta AN. Structural rearrangement of elastin under oxidative stress. Colloids Surf B Biointerfaces 2024; 233:113663. [PMID: 38008014 DOI: 10.1016/j.colsurfb.2023.113663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2023] [Revised: 11/11/2023] [Accepted: 11/19/2023] [Indexed: 11/28/2023]
Abstract
Reactive oxygen species (ROS) are key elements in several physiological processes. A high level of ROS leads to oxidative stress that damages biomolecules and is linked to many diseases like type-2 diabetes, cancer, inflammation, and many more. Here, our in-vitro study aimed to gauge the effect of ROS on the structural rearrangement of elastin through metal-catalyzed oxidation (MCO) at physiological temperature through laser light scattering, UV-vis, FTIR, and FESEM imaging. Light scattering data show a decrease in the hydrodynamic radius of elastin upon oxidation for the first hour. The rate of size reduction of ROS-treated elastin and the rate for self-assembly of bare elastin in the first two hours is found to be almost the same. However, the rate of association of ROS-treated is one order slower than the bare elastin after one hour. UV-vis absorption shows a blue shift accompanied by increased absorption, followed by a redshift and broadening of peak. FTIR data reveal changes in the secondary structures for both bare and oxidized elastin with time. While bare elastin coacervation increases unordered structure, the corresponding case of oxidized elastin saw a rise in β-sheet. FESEM images show the morphological changes occurring with time. Thus, we conclude that oxidative stress leads to structural rearrangement of the protein through interaction with the polar and hydrophobic domains, followed by aggregation. This study might be helpful for therapeutics focusing on preventing elastin degradation against aging.
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Affiliation(s)
- Debdip Brahma
- Biophysics and Soft Matter Laboratory, Department of Physics, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
| | - Tamal Sarkar
- Biophysics and Soft Matter Laboratory, Department of Physics, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
| | - Rupal Kaushik
- Biophysics and Soft Matter Laboratory, Department of Physics, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
| | - Akshay Narayan Sarangi
- Biophysics and Soft Matter Laboratory, Department of Physics, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
| | - Amar Nath Gupta
- Biophysics and Soft Matter Laboratory, Department of Physics, Indian Institute of Technology Kharagpur, Kharagpur 721302, India.
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3
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Kang ZL, Kong LH, Hu ZL, Li YP, Ma HJ. Effect of sodium bicarbonate and sodium chloride on protein conformation and gel properties of pork myofibrillar protein. ARAB J CHEM 2023. [DOI: 10.1016/j.arabjc.2023.104574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
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4
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Wang F, Gu X, Lü M, Huang Y, Zhu Y, Sun Y, Zhu X. Structural Analysis and Study of Gel Properties of Thermally-Induced Soybean Isolate-Potato Protein Gel System. Foods 2022; 11:foods11223562. [PMID: 36429154 PMCID: PMC9689681 DOI: 10.3390/foods11223562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2022] [Revised: 11/04/2022] [Accepted: 11/05/2022] [Indexed: 11/11/2022] Open
Abstract
Heat-induced composite gel systems consisting of different soybean protein isolate (SPI) and potato protein (PP) mixtures were studied to elucidate their "backbone" and property changes. This was achieved by comparing the ratio of non-network proteins, protein subunit composition, and aggregation of different gel samples. It was revealed that SPI was the "gel network backbone" and PP played the role of "filler" in the SPI-PP composite gel system. Compared with the composite gels at the same ratio, springiness and WHC decrease with PP addition. For hardness, PP addition showed a less linear trend. At the SPI-PP = 2/1 composite gel, hardness was more than doubled, while springiness and WHC did not decrease too much and increased the inter-protein binding. The hydrophobic interactions and electrostatic interactions and hydrogen bonding of the SPI gel system were enhanced. The scanning electron microscopy results showed that the SPI-based gel system was able to form a more compact and compatible gel network. This study demonstrates the use of PP as a potential filler that can effectively improve the gelling properties of SPI, thus providing a theoretical basis for the study of functional plant protein foods.
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Wang H, Wang P, Shen Q, Yang H, Xie H, Huang M, Zhang J, Zhao Q, Luo P, Jin D, Wu J, Jian S, Chen X. Insight into the effect of ultrasound treatment on the rheological properties of myofibrillar proteins based on the changes in their tertiary structure. Food Res Int 2022; 157:111136. [DOI: 10.1016/j.foodres.2022.111136] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Revised: 03/10/2022] [Accepted: 03/11/2022] [Indexed: 02/07/2023]
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6
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Hillebrandt N, Vormittag P, Dietrich A, Hubbuch J. Process Monitoring Framework for Cross‐flow Diafiltration‐based Virus‐like Particle Disassembly: Tracing Product Properties and Filtration Performance. Biotechnol Bioeng 2022; 119:1522-1538. [DOI: 10.1002/bit.28063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Revised: 02/09/2022] [Accepted: 02/10/2022] [Indexed: 11/09/2022]
Affiliation(s)
- Nils Hillebrandt
- Institute of Engineering in Life Sciences, Section IV: Biomolecular Separation Engineering, Karlsruhe Institute of Technology (KIT) Fritz‐Haber‐Weg 2 76131 Karlsruhe Baden‐Württemberg Germany
| | - Philipp Vormittag
- Institute of Engineering in Life Sciences, Section IV: Biomolecular Separation Engineering, Karlsruhe Institute of Technology (KIT) Fritz‐Haber‐Weg 2 76131 Karlsruhe Baden‐Württemberg Germany
| | - Annabelle Dietrich
- Institute of Engineering in Life Sciences, Section IV: Biomolecular Separation Engineering, Karlsruhe Institute of Technology (KIT) Fritz‐Haber‐Weg 2 76131 Karlsruhe Baden‐Württemberg Germany
| | - Jürgen Hubbuch
- Institute of Engineering in Life Sciences, Section IV: Biomolecular Separation Engineering, Karlsruhe Institute of Technology (KIT) Fritz‐Haber‐Weg 2 76131 Karlsruhe Baden‐Württemberg Germany
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7
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Zhou Z, Zhu M, Zhang G, Hu X, Pan J. Novel insights into the interaction mechanism of 5-hydroxymethyl-2-furaldehyde with β-casein and its effects on the structure and function of β-casein. Lebensm Wiss Technol 2021. [DOI: 10.1016/j.lwt.2021.112360] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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8
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Zhang A, Dong Y, Wang X, Zhao XH. Effect of the mass ratio of heat-treated whey protein isolate to anthocyanin on its composite properties. Int Dairy J 2021. [DOI: 10.1016/j.idairyj.2021.105158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Bolje A, Gobec S. Analytical Techniques for Structural Characterization of Proteins in Solid Pharmaceutical Forms: An Overview. Pharmaceutics 2021; 13:pharmaceutics13040534. [PMID: 33920461 PMCID: PMC8070348 DOI: 10.3390/pharmaceutics13040534] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 03/21/2021] [Accepted: 04/08/2021] [Indexed: 11/17/2022] Open
Abstract
Therapeutic proteins as biopharmaceuticals have emerged as a very important class of drugs for the treatment of many diseases. However, they are less stable compared to conventional pharmaceuticals. Their long-term stability in solid forms, which is critical for product performance, depends heavily on the retention of the native protein structure during the lyophilization (freeze-drying) process and, thereafter, in the solid state. Indeed, the biological function of proteins is directly related to the tertiary and secondary structure. Besides physical stability and biological activity, conformational stability (three-dimensional structure) is another important aspect when dealing with protein pharmaceuticals. Moreover, denaturation as loss of higher order structure is often a precursor to aggregation or chemical instability. Careful study of the physical and chemical properties of proteins in the dried state is therefore critical during biopharmaceutical drug development to deliver a final drug product with built-in quality that is safe, high-quality, efficient, and affordable for patients. This review provides an overview of common analytical techniques suitable for characterizing pharmaceutical protein powders, providing structural, and conformational information, as well as insights into dynamics. Such information can be very useful in formulation development, where selecting the best formulation for the drug can be quite a challenge.
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Affiliation(s)
- Aljoša Bolje
- Correspondence: (A.B.); (S.G.); Tel.: +386-147-69500 (A.B.); +386-147-69585 (S.G.)
| | - Stanislav Gobec
- Correspondence: (A.B.); (S.G.); Tel.: +386-147-69500 (A.B.); +386-147-69585 (S.G.)
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Le DT, Müller KM. In Vitro Assembly of Virus-Like Particles and Their Applications. Life (Basel) 2021; 11:334. [PMID: 33920215 PMCID: PMC8069851 DOI: 10.3390/life11040334] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 04/05/2021] [Accepted: 04/07/2021] [Indexed: 02/06/2023] Open
Abstract
Virus-like particles (VLPs) are increasingly used for vaccine development and drug delivery. Assembly of VLPs from purified monomers in a chemically defined reaction is advantageous compared to in vivo assembly, because it avoids encapsidation of host-derived components and enables loading with added cargoes. This review provides an overview of ex cella VLP production methods focusing on capsid protein production, factors that impact the in vitro assembly, and approaches to characterize in vitro VLPs. The uses of in vitro produced VLPs as vaccines and for therapeutic delivery are also reported.
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Affiliation(s)
| | - Kristian M. Müller
- Cellular and Molecular Biotechnology, Faculty of Technology, Bielefeld University, 33615 Bielefeld, Germany;
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11
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Athira S, Mann B, Sharma R, Pothuraju R, Bajaj RK. Preparation and characterization of iron-chelating peptides from whey protein: An alternative approach for chemical iron fortification. Food Res Int 2021; 141:110133. [PMID: 33642000 DOI: 10.1016/j.foodres.2021.110133] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 12/28/2020] [Accepted: 01/08/2021] [Indexed: 10/22/2022]
Abstract
Iron fortification of staple food is a strategy utilized worldwide to address the concern of dietary iron deficiency. However, traditional salt-based fortification methods have limitations with gastrointestinal stability and bioavailability. Iron chelating peptides from easily available and scalable proteins such as whey protein have been proposed as promising candidates to circumvent the above mentioned limitations by enhancing iron absorption and bioavailability. In this study, we report methods to produce whey protein derived iron-chelating peptides and describe their physicochemical characteristics. Peptides derived from whey proteins prepared by ultrafiltration of whey followed by hydrolysation were iron chelated to produce peptide-iron complexes. These complexes had a size of 422.9 ± 3.41 nm, chelated iron content of 36.42 µg/ mg protein, and a low zeta potential (-10.80 mV) compared to whey peptides. Spectra analysis using ultraviolet-visible absorption and Fourier transform infrared spectroscopy showed structural transformation indicating iron chelation. Mass spectrometric analysis using LC-MS/MS confirmed the presence of both hydrophilic and hydrophobic peptides in the complexes with sizes ranging from 275 Da to 1916 Da. Furthermore, reduction in the antioxidant property of peptides following iron complexing indicates iron chelation. Our results suggest that whey protein derived peptide-iron complexes can be used as a potential alternative for chemical iron fortificants for food products and also as iron supplements.
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Affiliation(s)
- S Athira
- Dairy Chemistry Division, ICAR-National Dairy Research Institute, Karnal 132001, Haryana, India
| | - Bimlesh Mann
- Dairy Chemistry Division, ICAR-National Dairy Research Institute, Karnal 132001, Haryana, India.
| | - Rajan Sharma
- Dairy Chemistry Division, ICAR-National Dairy Research Institute, Karnal 132001, Haryana, India
| | - Ramesh Pothuraju
- Dairy Chemistry Division, ICAR-National Dairy Research Institute, Karnal 132001, Haryana, India
| | - Rajesh Kumar Bajaj
- Dairy Chemistry Division, ICAR-National Dairy Research Institute, Karnal 132001, Haryana, India
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12
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Liu Q, Li Z, Pan X, Dai Y, Hou H, Wang W, Ding X, Zhang H, Li X, Dong H. Effect of grinding on the structure of pea protein isolate and the rheological properties of its acid‐induced gels. Int J Food Sci Technol 2021. [DOI: 10.1111/ijfs.14969] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Qiaozhen Liu
- College of Food Science and Engineering Shandong Agricultural University Tai’an Shandong271018China
- Engineering and Technology Center for Grain Processing in Shandong Province Tai’an Shandong271018China
| | - Zhuowa Li
- College of Food Science and Pharmaceutical Engineering Zaozhuang University Zaozhuang Shandong277000China
| | - Xiaoxue Pan
- College of Food Science and Engineering Shandong Agricultural University Tai’an Shandong271018China
- Engineering and Technology Center for Grain Processing in Shandong Province Tai’an Shandong271018China
| | - Yangyong Dai
- College of Food Science and Engineering Shandong Agricultural University Tai’an Shandong271018China
- Engineering and Technology Center for Grain Processing in Shandong Province Tai’an Shandong271018China
| | - Hanxue Hou
- College of Food Science and Engineering Shandong Agricultural University Tai’an Shandong271018China
- Engineering and Technology Center for Grain Processing in Shandong Province Tai’an Shandong271018China
| | - Wentao Wang
- College of Food Science and Engineering Shandong Agricultural University Tai’an Shandong271018China
- Engineering and Technology Center for Grain Processing in Shandong Province Tai’an Shandong271018China
| | - Xiuzhen Ding
- College of Food Science and Engineering Shandong Agricultural University Tai’an Shandong271018China
- Engineering and Technology Center for Grain Processing in Shandong Province Tai’an Shandong271018China
| | - Hui Zhang
- College of Food Science and Engineering Shandong Agricultural University Tai’an Shandong271018China
- Engineering and Technology Center for Grain Processing in Shandong Province Tai’an Shandong271018China
| | - Xiangyang Li
- College of Food Science and Engineering Shandong Agricultural University Tai’an Shandong271018China
- Engineering and Technology Center for Grain Processing in Shandong Province Tai’an Shandong271018China
| | - Haizhou Dong
- College of Food Science and Engineering Shandong Agricultural University Tai’an Shandong271018China
- Engineering and Technology Center for Grain Processing in Shandong Province Tai’an Shandong271018China
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13
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Krämer I, Thiesen J, Astier A. Formulation and Administration of Biological Medicinal Products". Pharm Res 2020; 37:159. [PMID: 32743712 DOI: 10.1007/s11095-020-02859-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 06/12/2020] [Indexed: 10/23/2022]
Abstract
Monoclonal antibody (Mabs) containing medicinal products are widely used in clinical practice. Prior to parenteral administration, licensed Mab containing medicinal products are transferred to the ready-to-administer (RTA) forms. Reconstitution and/or preparation should follow the guidelines for Good Reconstitution/Good Preparation Practice. Preparation in the pharmacy must take place within the framework of a suitable quality management system. The responsible pharmacist must apply a risk assessment on the process to ensure the appropriate quality of the RTA preparation, especially because the extent of quality testing is limited by batch size (often one single unit) and time restraints. In these cases, appropriate quality is to be assured by means of qualification activities, environmental monitoring, process validation with growth medium and in-process controls. Correct labelling of the Mab containing RTA preparations includes a suitable storage advice and a defined shelf life. Physicochemical stability of a given Mab preparation can be assessed based on a specific stability study (supplied by the manufacturer in the SmPC or scientific journals, study published by an expert in a peer-reviewed scientific journal). Physicochemical stability studies require the use of various orthogonal physicochemical methods to detect accurately the degradation changes that may result from the deamidation, oxidation, disulfide formation, aggregation or fragmentation during storage. Complementary, biological activity can be measured. Compatibility studies of Mabs and devices used for preparation and administration are still scarce. Microbiological stability of Mab preparations is related to the complexity of the preparation process, the growth supporting nature of the preparation and the integrity of the container or container/closure combination. In use viability tests revealed that the potential of Mab preparations to support microbial growth was similar to that of the pure vehicle solutions used as control solutions. The enumerated microbial counts varied according to the species utilized and the type of Mab preparation. If sterility testing of the individual preparation is impossible, maximum permitted shelf life can be assessed empirically with regard to the maximum shelf lives defined in the USP <797> monograph. Finally, microbiological and physicochemical stability are to be considered concurrently when determining the shelf life of an individual Mab preparation. In each case, shelf life should be limited according to the shorter period of proven stability, either derived from the microbiological or physicochemical stability data.
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Affiliation(s)
- Irene Krämer
- Pharmacy Department, University Medical Center, Johannes Gutenberg-University Mainz, Mainz, Germany.
| | - Judith Thiesen
- Pharmacy Department, University Medical Center, Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Alain Astier
- Pharmacy Department, Henri Mondor University Hospital, Créteil, France
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14
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Chen Y, Ma M. Foam and conformational changes of egg white as affected by ultrasonic pretreatment and phenolic binding at neutral pH. Food Hydrocoll 2020. [DOI: 10.1016/j.foodhyd.2019.105568] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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15
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A biophysical strategy to examine the impact of newly synthesized polymerizable ammonium-based ionic liquids on the structural stability and proteolytic activity of stem bromelain. Int J Biol Macromol 2020; 151:957-966. [DOI: 10.1016/j.ijbiomac.2019.10.208] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 10/14/2019] [Accepted: 10/24/2019] [Indexed: 11/23/2022]
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16
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Multi-attribute PAT for UF/DF of Proteins-Monitoring Concentration, particle sizes, and Buffer Exchange. Anal Bioanal Chem 2020; 412:2123-2136. [PMID: 32072210 DOI: 10.1007/s00216-019-02318-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 10/25/2019] [Accepted: 12/03/2019] [Indexed: 01/08/2023]
Abstract
Ultrafiltration/diafiltration (UF/DF) plays an important role in the manufacturing of biopharmaceuticals. Monitoring critical process parameters and quality attributes by process analytical technology (PAT) during those steps can facilitate process development and assure consistent quality in production processes. In this study, a lab-scale cross-flow filtration (CFF) device was equipped with a variable pathlength (VP) ultraviolet and visible (UV/Vis) spectrometer, a light scattering photometer, and a liquid density sensor (microLDS). Based on the measured signals, the protein concentration, buffer exchange, apparent molecular weight, and hydrodynamic radius were monitored. The setup was tested in three case studies. First, lysozyme was used in an UF/DF run to show the comparability of on-line and off-line measurements. The corresponding correlation coefficients exceeded 0.97. Next, urea-induced changes in protein size of glucose oxidase (GOx) were monitored during two DF steps. Here, correlation coefficients were ≥ 0.92 for static light scattering (SLS) and dynamic light scattering (DLS). The correlation coefficient for the protein concentration was 0.82, possibly due to time-dependent protein precipitation. Finally, a case study was conducted with a monoclonal antibody (mAb) to show the full potential of this setup. Again, off-line and on-line measurements were in good agreement with all correlation coefficients exceeding 0.92. The protein concentration could be monitored in-line in a large range from 3 to 120 g L- 1. A buffer-dependent increase in apparent molecular weight of the mAb was observed during DF, providing interesting supplemental information for process development and stability assessment. In summary, the developed setup provides a powerful testing system for evaluating different UF/DF processes and may be a good starting point to develop process control strategies. Graphical Abstract Piping and instrumentation diagram of the experimental setup and data generated by the different sensors. A VP UV/Vis spectrometer (FlowVPE, yellow) measures the protein concentration. From the data of the light scattering photometer (Zetasizer, green) in the on-line measurement loop, the apparant molecular weight and z-average are calculated. The density sensor (microLDS) measures density and viscosity of the fluid in the on-line loop.
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17
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Lavrinenko IA, Holyavka MG, Chernov VE, Artyukhov VG. Second derivative analysis of synthesized spectra for resolution and identification of overlapped absorption bands of amino acid residues in proteins: Bromelain and ficin spectra in the 240-320 nm range. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2020; 227:117722. [PMID: 31707026 DOI: 10.1016/j.saa.2019.117722] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 09/16/2019] [Accepted: 10/27/2019] [Indexed: 06/10/2023]
Abstract
We establish the origin and formation of peaks in UV absorption spectra of proteins by applying the second derivative analysis to (i) spectra of the native protein, (ii) to its model spectra "synthesized" as a sum of partial free amino acid spectra and (iii) to absorption spectra of the free amino acids. We show that the bromelain peaks at 248.2, 253.2, 258.4 and 264.2 nm are due to phenylalanine maxima; the predictable peak at 279.6 nm (which is almost coincident with the extremum of the zero-order spectrum at 279.4 nm) is mainly due to tyrosine maximum, while the peaks at 274.6 and 290.6 nm are due to tryptophan maximum; 268.0 nm peak to the superposition of tyrosine and phenylalanine maxima, and 283.4 nm peak to the superposition of tyrosine and tryptophan maxima. Similar results are obtained for ficin: the peaks at 248.4, 253.0 and 258.8 nm are formed by the phenylalanine maxima, the predictable peak at 264.4 nm accords with the corresponding bromelain 264.2 nm peak; the 279.4 nm peak almost coincides with the zero order spectrum peak (279.6 nm), but it is expressed stronger than that of bromelain due to a different ratio of tyrosine to tryptophan side groups. The peaks at 273.4 and 290.6 nm are associated with tryptophan, the 268.0 nm peak being mainly due to tyrosine (and fractionally to phenylalanine); and the 283.8 nm peak belongs to tyrosine and, to a greater extent, to tryptophan. We demonstrate that the amino acid residues of tryptophan, tyrosine and phenylalanine undergo correspondingly the largest, intermediate and the lowest positive (red) wavelength shift in the zero-order protein absorption spectrum with respect to the model (synthesized) spectrum. The difference appearing in the positions of the bromelain and ficin absorption band peaks is determined by superposition of relative contributions from amino acid residues. This superposition is resulted from (i) linear combination of amino acid residues spectra and (ii) their different (non-uniform) wavelength shifts as functions of microenvironment of these residues' chromophores. The proposed approach to the analysis of the protein absorption spectra with the help of "synthesized" spectra can be transferred to other objects studied in analytical and organic chemistry of high molecular compounds containing monomer units with various chromophores.
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18
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Rüdt M, Vormittag P, Hillebrandt N, Hubbuch J. Process monitoring of virus-like particle reassembly by diafiltration with UV/Vis spectroscopy and light scattering. Biotechnol Bioeng 2019; 116:1366-1379. [PMID: 30684365 PMCID: PMC6593973 DOI: 10.1002/bit.26935] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Revised: 01/14/2019] [Accepted: 01/22/2019] [Indexed: 12/20/2022]
Abstract
Virus-like particles (VLPs) have shown great potential as biopharmaceuticals in the market and in clinics. Nonenveloped, in vivo assembled VLPs are typically disassembled and reassembled in vitro to improve particle stability, homogeneity, and immunogenicity. At the industrial scale, cross-flow filtration (CFF) is the method of choice for performing reassembly by diafiltration. Here, we developed an experimental CFF setup with an on-line measurement loop for the implementation of process analytical technology (PAT). The measurement loop included an ultraviolet and visible (UV/Vis) spectrometer as well as a light scattering photometer. These sensors allowed for monitoring protein concentration, protein tertiary structure, and protein quaternary structure. The experimental setup was tested with three Hepatitis B core Antigen (HBcAg) variants. With each variant, three reassembly processes were performed at different transmembrane pressures (TMPs). While light scattering provided information on the assembly progress, UV/Vis allowed for monitoring the protein concentration and the rate of VLP assembly based on the microenvironment of Tyrosine-132. VLP formation was verified by off-line dynamic light scattering (DLS) and transmission electron microscopy (TEM). Furthermore, the experimental results provided evidence of aggregate-related assembly inhibition and showed that off-line size-exclusion chromatography does not provide a complete picture of the particle content. Finally, a Partial-Least Squares (PLS) model was calibrated to predict VLP concentrations in the process solution. Q 2 values of 0.947-0.984 were reached for the three HBcAg variants. In summary, the proposed experimental setup provides a powerful platform for developing and monitoring VLP reassembly steps by CFF.
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Affiliation(s)
- Matthias Rüdt
- Institute of Engineering in Life Sciences, Section IV: Biomolecular Separation EngineeringKarlsruhe Institute of Technology (KIT)KarlsruheGermany
| | - Philipp Vormittag
- Institute of Engineering in Life Sciences, Section IV: Biomolecular Separation EngineeringKarlsruhe Institute of Technology (KIT)KarlsruheGermany
| | - Nils Hillebrandt
- Institute of Engineering in Life Sciences, Section IV: Biomolecular Separation EngineeringKarlsruhe Institute of Technology (KIT)KarlsruheGermany
| | - Jürgen Hubbuch
- Institute of Engineering in Life Sciences, Section IV: Biomolecular Separation EngineeringKarlsruhe Institute of Technology (KIT)KarlsruheGermany
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19
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Cao M, Wang J, Cao A, Shiuan D, Guan R, Cai L, Wang Y. The impact of recrystallisation on the freeze‐thaw cycles of red seabream (
Pagrus major
) fillets. Int J Food Sci Technol 2018. [DOI: 10.1111/ijfs.14039] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Minjie Cao
- College of Food Science and Engineering, National & Local Joint Engineering Research Center of Storage, Processing and Safety Control Technology for Fresh Agricultural and Aquatic Products Bohai University Jinzhou 121013 China
| | - Jing Wang
- China Rural Technology Development Center Beijing 100045 China
| | - Ailing Cao
- Hangzhou Customs District Hangzhou 310007 China
| | - David Shiuan
- College of Food Science and Engineering, National & Local Joint Engineering Research Center of Storage, Processing and Safety Control Technology for Fresh Agricultural and Aquatic Products Bohai University Jinzhou 121013 China
| | - Rongfa Guan
- Zhejiang Provincial Key Laboratory of Biometrology and Inspection and Quarantine China Jiliang University Hangzhou 310018 China
| | - Luyun Cai
- College of Food Science and Engineering, National & Local Joint Engineering Research Center of Storage, Processing and Safety Control Technology for Fresh Agricultural and Aquatic Products Bohai University Jinzhou 121013 China
| | - Yanbo Wang
- College of Food Science and Biotechnology Zhejiang Gongshang University Hangzhou 310018 China
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20
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Andris S, Rüdt M, Rogalla J, Wendeler M, Hubbuch J. Monitoring of antibody-drug conjugation reactions with UV/Vis spectroscopy. J Biotechnol 2018; 288:15-22. [DOI: 10.1016/j.jbiotec.2018.10.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 10/09/2018] [Accepted: 10/10/2018] [Indexed: 02/06/2023]
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21
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Rüdt M, Andris S, Schiemer R, Hubbuch J. Factorization of preparative protein chromatograms with hard-constraint multivariate curve resolution and second-derivative pretreatment. J Chromatogr A 2018; 1585:152-160. [PMID: 30528712 DOI: 10.1016/j.chroma.2018.11.065] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Revised: 11/21/2018] [Accepted: 11/23/2018] [Indexed: 10/27/2022]
Abstract
Current biopharmaceutical production heavily relies on chromatography for protein purification. Recently, research has intensified towards finding suitable solutions to monitoring the chromatographic steps by multivariate spectroscopic sensors. Here, hard-constraint multivariate curve resolution (MCR) was investigated as a calibration-free method for factorizing bilinear preparative protein chromatograms into concentrations and spectra. Protein elutions were assumed to follow exponentially modified Gaussian (EMG) curves. In three case studies, MCR was applied to chromatograms of second-derivative ultraviolet and visible (UV-vis) spectra. The three case studies consisted of the separation of a ternary mixture (ribonuclease A, cytochrome c, and lysozyme), multiple binary chromatography runs of cytochrome c and lysozyme, and the separation of an antibody-drug conjugate (ADC) from unconjugated immunoglobulin G (IgG). In all case studies, good estimates of the elution curves were obtained. R2 values compared to off-line analytics exceeded 0.90. The estimated spectra allowed for protein identification based on a protein spectral library. In summary, MCR was shown to be well able to factorize protein chromatograms without prior calibration. The method may thus substantially simplify analysis of multivariate protein chromatograms with multiple co-eluting species. It may be especially useful in process development.
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Affiliation(s)
- Matthias Rüdt
- Institute of Engineering in Life Sciences, Section IV: Biomolecular Separation Engineering, Karlsruhe Institute of Technology, Fritz-Haber-Weg 2, 76131 Karlsruhe, Germany
| | - Sebastian Andris
- Institute of Engineering in Life Sciences, Section IV: Biomolecular Separation Engineering, Karlsruhe Institute of Technology, Fritz-Haber-Weg 2, 76131 Karlsruhe, Germany
| | - Robin Schiemer
- Institute of Engineering in Life Sciences, Section IV: Biomolecular Separation Engineering, Karlsruhe Institute of Technology, Fritz-Haber-Weg 2, 76131 Karlsruhe, Germany
| | - Jürgen Hubbuch
- Institute of Engineering in Life Sciences, Section IV: Biomolecular Separation Engineering, Karlsruhe Institute of Technology, Fritz-Haber-Weg 2, 76131 Karlsruhe, Germany.
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22
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Blaffert J, Haeri HH, Blech M, Hinderberger D, Garidel P. Spectroscopic methods for assessing the molecular origins of macroscopic solution properties of highly concentrated liquid protein solutions. Anal Biochem 2018; 561-562:70-88. [PMID: 30243977 DOI: 10.1016/j.ab.2018.09.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2018] [Revised: 09/08/2018] [Accepted: 09/17/2018] [Indexed: 01/14/2023]
Abstract
In cases of subcutaneous injection of therapeutic monoclonal antibodies, high protein concentrations (>50 mg/ml) are often required. During the development of these high concentration liquid formulations (HCLF), challenges such as aggregation, gelation, opalescence, phase separation, and high solution viscosities are more prone compared to low concentrated protein formulations. These properties can impair manufacturing processes, as well as protein stability and shelf life. To avoid such unfavourable solution properties, a detailed understanding about the nature of these properties and their driving forces are required. However, the fundamental mechanisms that lead to macroscopic solution properties, as above mentioned, are complex and not fully understood, yet. Established analytical methods for assessing the colloidal stability, i.e. the ability of a native protein to remain dispersed in solution, are restricted to dilute conditions and provide parameters such as the second osmotic virial coefficient, B22, and the diffusion interaction coefficient, kD. These parameters are routinely applied for qualitative estimations and identifications of proteins with challenging solution behaviours, such as high viscosities and aggregation, although the assays are prepared for low protein concentration conditions, typically between 0.1 and 20 mg/ml ("ideal" solution conditions). Quantitative analysis of samples of high protein concentration is difficult and it is hard to obtain information about the driving forces of such solution properties and corresponding protein-protein self-interactions. An advantage of using specific spectroscopic methods is the potential of directly analysing highly concentrated protein solutions at different solution conditions. This allows for collecting/gaining valuable information about the fundamental mechanisms of solution properties of the high protein concentration regime. In addition, the derived parameters might be more predictive as compared to the parameters originating from assays which are optimized for the low protein concentration range. The provided information includes structural data, molecular dynamics at various timescales and protein-solvent interactions, which can be obtained at molecular resolution. Herein, we provide an overview about spectroscopic techniques for analysing the origins of macroscopic solution behaviours in general, with a specific focus on pharmaceutically relevant high protein concentration and formulation conditions.
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Affiliation(s)
- Jacob Blaffert
- Institute of Chemistry, Martin Luther University Halle-Wittenberg, Von-Danckelmann-Platz 4, 06120, Halle/Saale, Germany
| | - Haleh Hashemi Haeri
- Institute of Chemistry, Martin Luther University Halle-Wittenberg, Von-Danckelmann-Platz 4, 06120, Halle/Saale, Germany
| | - Michaela Blech
- Boehringer Ingelheim Pharma GmbH & Co. KG, Protein Science, Birkerndorfer Str. 65, 88397, Biberach/Riß, Germany
| | - Dariush Hinderberger
- Institute of Chemistry, Martin Luther University Halle-Wittenberg, Von-Danckelmann-Platz 4, 06120, Halle/Saale, Germany
| | - Patrick Garidel
- Institute of Chemistry, Martin Luther University Halle-Wittenberg, Von-Danckelmann-Platz 4, 06120, Halle/Saale, Germany; Boehringer Ingelheim Pharma GmbH & Co. KG, Protein Science, Birkerndorfer Str. 65, 88397, Biberach/Riß, Germany.
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23
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Pawlowski JW, Bajardi-Taccioli A, Houde D, Feschenko M, Carlage T, Kaltashov IA. Influence of glycan modification on IgG1 biochemical and biophysical properties. J Pharm Biomed Anal 2018; 151:133-144. [DOI: 10.1016/j.jpba.2017.12.061] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 12/29/2017] [Accepted: 12/31/2017] [Indexed: 02/04/2023]
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24
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Zhang M, Li F, Diao X, Kong B, Xia X. Moisture migration, microstructure damage and protein structure changes in porcine longissimus muscle as influenced by multiple freeze-thaw cycles. Meat Sci 2017; 133:10-18. [DOI: 10.1016/j.meatsci.2017.05.019] [Citation(s) in RCA: 164] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 05/19/2017] [Accepted: 05/25/2017] [Indexed: 11/29/2022]
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25
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Biophysical Characterization and Thermal Stability of Pneumococcal Histidine Triad Protein D in the Presence of Zinc and Manganese. J Pharm Sci 2017. [DOI: 10.1016/j.xphs.2017.06.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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26
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Caetano-Silva ME, Alves RC, Lucena GN, Frem RCG, Bertoldo-Pacheco MT, Lima-Pallone JA, Netto FM. Synthesis of whey peptide-iron complexes: Influence of using different iron precursor compounds. Food Res Int 2017; 101:73-81. [PMID: 28941699 DOI: 10.1016/j.foodres.2017.08.056] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Revised: 08/11/2017] [Accepted: 08/25/2017] [Indexed: 10/18/2022]
Abstract
Iron-binding peptides are an alternative for increasing the bioavailability of iron and to decreasing its pro-oxidant effect. This study aimed to synthesize and characterize peptide-iron complexes using FeCl2 or FeSO4 as the iron precursor compounds. Whey protein isolate (WPI), WPI hydrolyzed with pancreatin, and its fractions obtained via ultrafiltration (cut-off 5kDa) were used as ligands. The fluorescence intensity of the ligands significantly decreased as the iron concentration increased as a result of metal coordination with the iron-binding sites, which may have led to changes in the microenvironment of tryptophan. For both iron precursor compounds, the primary iron-binding site was carboxylate groups, and the linkage occurred via a bidentate coordination mode with two vibrational modes assigned to the COOFe linkage. However, infrared spectroscopy and thermal analysis results showed that the dynamics of the interaction is different for the iron precursor. The iron source may be of great importance because it may impact iron absorption and the pro-oxidant effect of the mineral.
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Affiliation(s)
- Maria Elisa Caetano-Silva
- Faculty of Food Engineering, University of Campinas, UNICAMP, Monteiro Lobato 80, 13083-862 Campinas, SP, Brazil.
| | - Renata Carolina Alves
- Institute of Chemistry, São Paulo State University, UNESP, Prof. Francisco Degni 55, PO Box 355, 14800-970 Araraquara, SP, Brazil.
| | - Guilherme Nunes Lucena
- Institute of Chemistry, São Paulo State University, UNESP, Prof. Francisco Degni 55, PO Box 355, 14800-970 Araraquara, SP, Brazil.
| | - Regina Célia Galvão Frem
- Institute of Chemistry, São Paulo State University, UNESP, Prof. Francisco Degni 55, PO Box 355, 14800-970 Araraquara, SP, Brazil.
| | - Maria Teresa Bertoldo-Pacheco
- Center of Food Science and Quality, Institute of Food Technology, ITAL, Brasil Ave 2880, 13070-178 Campinas, SP, Brazil.
| | - Juliana Azevedo Lima-Pallone
- Faculty of Food Engineering, University of Campinas, UNICAMP, Monteiro Lobato 80, 13083-862 Campinas, SP, Brazil.
| | - Flavia Maria Netto
- Faculty of Food Engineering, University of Campinas, UNICAMP, Monteiro Lobato 80, 13083-862 Campinas, SP, Brazil.
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27
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Sun N, Cui P, Jin Z, Wu H, Wang Y, Lin S. Contributions of molecular size, charge distribution, and specific amino acids to the iron-binding capacity of sea cucumber ( Stichopus japonicus ) ovum hydrolysates. Food Chem 2017; 230:627-636. [DOI: 10.1016/j.foodchem.2017.03.077] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 02/27/2017] [Accepted: 03/13/2017] [Indexed: 11/25/2022]
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28
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A Multiparticulate Delivery System for Potential Colonic Targeting Using Bovine Serum Albumin as a Model Protein : Theme: Formulation and Manufacturing of Solid Dosage Forms Guest Editors: Tony Zhou and Tonglei Li. Pharm Res 2017; 34:2663-2674. [PMID: 28808837 DOI: 10.1007/s11095-017-2237-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Accepted: 07/25/2017] [Indexed: 12/18/2022]
Abstract
PURPOSE There are many important diseases whose treatment could be improved by delivering a therapeutic protein to the colon, for example, Clostridium difficile infection, ulcerative colitis and Crohn's Disease. The goal of this project was to investigate the feasibility of colonic delivery of proteins using multiparticulate beads. METHODS In this work, bovine serum albumin (BSA) was adopted as a model protein. BSA was spray layered onto beads, followed by coating of an enteric polymer EUDRAGIT® FS 30 D to develop a colonic delivery system. The secondary and tertiary structure change and aggregation of BSA during spray layering process was examined. The BSA layered beads were then challenged in an accelerated stability study using International Council for Harmonization (ICH) conditions. The in vitro release of BSA from enteric coated beads was examined using United States Pharmacopeia (USP) dissolution apparatus 1. RESULTS No significant changes in the secondary and tertiary structure or aggregation profile of BSA were observed after the spray layering process. Degradation of BSA to different extents was detected after storing at 25°C and 40°C for 38 days. Enteric coated BSA beads were intact in acidic media while released BSA in pH 7.4 phosphate buffer. CONCLUSION We showed the feasibility of delivering proteins to colon in vitro using multiparticulate system.
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29
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Rani A, Taha M, Venkatesu P, Lee MJ. Coherent Experimental and Simulation Approach To Explore the Underlying Mechanism of Denaturation of Stem Bromelain in Osmolytes. J Phys Chem B 2017; 121:6456-6470. [DOI: 10.1021/acs.jpcb.7b01776] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Anjeeta Rani
- Department
of Chemistry, University of Delhi, Delhi 110 007, India
| | - Mohamed Taha
- Department
of Chemistry, College of Science, Sultan Qaboos University, PO Box 36, PC 123 Muscat, Oman
| | | | - Ming- Jer Lee
- Department of Chemical Engineering, National Taiwan University of Science & Technology, Taipei 10607, Taiwan
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30
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Guo Y, Shen L, Yao X, Liu Y, Liu Y, Chen H, Min K, Zheng X. Spectroscopic and molecular docking study on the structure-affinity relationship and mechanism in the interaction of genistein and its derivatives with bovine serum albumin. LUMINESCENCE 2017; 32:1368-1384. [DOI: 10.1002/bio.3333] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Revised: 01/07/2017] [Accepted: 03/01/2017] [Indexed: 11/09/2022]
Affiliation(s)
- Yu Guo
- Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, Institute of Pharmacy and Pharmacology; University of South China, Hengyang; Hu'nan China
| | - Lixian Shen
- Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, Institute of Pharmacy and Pharmacology; University of South China, Hengyang; Hu'nan China
| | - Xu Yao
- Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, Institute of Pharmacy and Pharmacology; University of South China, Hengyang; Hu'nan China
| | - Yang Liu
- Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, Institute of Pharmacy and Pharmacology; University of South China, Hengyang; Hu'nan China
| | - Yunmei Liu
- Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, Institute of Pharmacy and Pharmacology; University of South China, Hengyang; Hu'nan China
| | - Hongfei Chen
- Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, Institute of Pharmacy and Pharmacology; University of South China, Hengyang; Hu'nan China
| | - Ke Min
- Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, Institute of Pharmacy and Pharmacology; University of South China, Hengyang; Hu'nan China
| | - Xing Zheng
- Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, Institute of Pharmacy and Pharmacology; University of South China, Hengyang; Hu'nan China
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31
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Cao Y, Xiong YL. Interaction of Whey Proteins with Phenolic Derivatives Under Neutral and Acidic pH Conditions. J Food Sci 2017; 82:409-419. [DOI: 10.1111/1750-3841.13607] [Citation(s) in RCA: 97] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Revised: 12/09/2016] [Accepted: 12/09/2016] [Indexed: 01/21/2023]
Affiliation(s)
- Yanyun Cao
- State Key Laboratory of Food Science and Technology and School of Food Science and Technology; Jiangnan Univ; Wuxi Jiangsu 214122 China
| | - Youling L. Xiong
- Dept. of Animal and Food Sciences; Univ. of Kentucky; Lexington KY 40546 U.S.A
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32
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Effect of low frequency ultrasonication on biochemical and structural properties of chicken actomyosin. Food Chem 2016; 205:43-51. [DOI: 10.1016/j.foodchem.2016.03.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Revised: 02/11/2016] [Accepted: 03/01/2016] [Indexed: 11/20/2022]
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33
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Huang Y, Guo L, Xiong S, Li A. Property and structure changes of myofibril protein in pork treated by high pressure combined with heat. FOOD SCI TECHNOL INT 2016; 22:647-662. [PMID: 27091151 DOI: 10.1177/1082013216642610] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2016] [Accepted: 03/08/2016] [Indexed: 11/17/2022]
Abstract
The effects of myofibril protein in pork treated by high hydrostatic pressure combined with heat were investigated. The solubility of myofibril protein significantly increased up to 400 MPa but since then began to decrease up to 600 MPa. The best solubility was shown under all pressure at 35 ℃ and the lowest solubility was observed at 55 ℃. The carbonyl group value, disulfide bond and surface hydrophobicity exhibited pressure-dependent increase in the same manner. Particle size decreased up to 400 MPa and then increased up to 600 MPa, but the turbidity always reduced. The increase of intrinsic fluorescence intensity with red shift and decrease of absorbance around 278 nm with blue shift indicated that protein unfolding and exposure of hydrophobic amino acid occurred with increase of pressure. The second derivative infrared spectra and curve fittings suggested that high pressure induced reduction of β-sheet structures, enhancement of α-helix and random coil and β-turns segments, which was opposite to the effects of temperature. Emission scanning electron microscope assay further demonstrated protein unfolding and aggregation process induced by different pressure and temperature. The data suggested that cooperative effect of moderate pressure and temperature could improve physical-chemical and processing properties of meat.
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Affiliation(s)
- Yechuan Huang
- School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan, PR China Engineering Research Center for Biomass Resource Utilization and Modification of Sichuan Province, Mianyang, Sichuan, PR China
| | - Liping Guo
- School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan, PR China
| | - Shuangli Xiong
- School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan, PR China Engineering Research Center for Biomass Resource Utilization and Modification of Sichuan Province, Mianyang, Sichuan, PR China
| | - Anlin Li
- School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan, PR China
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34
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Li R, Wu Z, Wang Y, Ding L, Wang Y. β-Cyclodextrin preventing protein aggregation in foam fractionation of bovine serum albumin. J Biotechnol 2016; 220:33-4. [DOI: 10.1016/j.jbiotec.2016.01.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 01/08/2016] [Accepted: 01/12/2016] [Indexed: 10/22/2022]
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35
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Randall L, Manta B, Nelson KJ, Santos J, Poole LB, Denicola A. Structural changes upon peroxynitrite-mediated nitration of peroxiredoxin 2; nitrated Prx2 resembles its disulfide-oxidized form. Arch Biochem Biophys 2016; 590:101-108. [PMID: 26612102 PMCID: PMC9123601 DOI: 10.1016/j.abb.2015.11.032] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Revised: 11/15/2015] [Accepted: 11/16/2015] [Indexed: 12/12/2022]
Abstract
Peroxiredoxins are cys-based peroxidases that function in peroxide detoxification and H2O2-induced signaling. Human Prx2 is a typical 2-Cys Prx arranged as pentamers of head-to-tail homodimers. During the catalytic mechanism, the active-site cysteine (CP) cycles between reduced, sulfenic and disulfide state involving conformational as well as oligomeric changes. Several post-translational modifications were shown to affect Prx activity, in particular CP overoxidation which leads to inactivation. We have recently reported that nitration of Prx2, a post-translational modification on non-catalytic tyrosines, unexpectedly increases its peroxidase activity and resistance to overoxidation. To elucidate the cross-talk between this post-translational modification and the enzyme catalysis, we investigated the structural changes of Prx2 after nitration. Analytical ultracentrifugation, UV absorption, circular dichroism, steady-state and time-resolved fluorescence were used to connect catalytically relevant redox changes with tyrosine nitration. Our results show that the reduced nitrated Prx2 structurally resembles the disulfide-oxidized native form of the enzyme favoring a locally unfolded conformation that facilitates disulfide formation. These results provide structural basis for the kinetic analysis previously reported, the observed increase in activity and the resistance to overoxidation of the peroxynitrite-treated enzyme.
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Affiliation(s)
- Lía Randall
- Laboratorio de Fisicoquímica Biológica, Instituto de Química Biológica, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay; Center for Free Radical and Biomedical Research, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Bruno Manta
- Laboratory Redox Biology of Trypanosomes, Institut Pasteur de Montevideo, Uruguay; Laboratorio de Fisicoquímica Biológica, Instituto de Química Biológica, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Kimberly J Nelson
- Department of Biochemistry, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Javier Santos
- IQUIFIB (UBA-CONICET) and Departamento de Química Biológica, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Ciudad Autónoma de Buenos Aires, Argentina
| | - Leslie B Poole
- Department of Biochemistry, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Ana Denicola
- Laboratorio de Fisicoquímica Biológica, Instituto de Química Biológica, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay; Center for Free Radical and Biomedical Research, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay.
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36
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Wahome N, Cooper A, Thapa P, Choudhari S, Gao FP, Volkin DB, Middaugh CR. Production of Well-Characterized Virus-like Particles in an Escherichia coli-Based Expression Platform for Preclinical Vaccine Assessments. Methods Mol Biol 2016; 1404:437-457. [PMID: 27076315 DOI: 10.1007/978-1-4939-3389-1_29] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
In this chapter we demonstrate a method to produce virus-like particles (VLPs) from Escherichia coli. Standard bacterial protocols are used for the cloning, transformation, and expression of the protein subunits. A two-step protein purification method is highlighted: one step based on separating soluble proteins with ion-exchange affinity chromatography and a second polishing step using size-exclusion columns to isolate VLP species. The ensuing VLPs can be characterized with a variety of biophysical techniques including ultraviolet (UV)-visible spectroscopy for protein quantification, dynamic light scattering for size distribution determination, and transmission electron microscopy to ascertain size and morphology.
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MESH Headings
- Capsid Proteins/genetics
- Cloning, Molecular
- Drug Evaluation, Preclinical
- Dynamic Light Scattering
- Escherichia coli/genetics
- Genetic Engineering/methods
- Microscopy, Electron, Transmission
- Spectrophotometry, Ultraviolet
- Transformation, Genetic
- Vaccines, Virus-Like Particle/biosynthesis
- Vaccines, Virus-Like Particle/chemistry
- Vaccines, Virus-Like Particle/genetics
- Vaccines, Virus-Like Particle/isolation & purification
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Affiliation(s)
- Newton Wahome
- Department of Pharmaceutical Chemistry, Macromolecule and Vaccine Stabilization Center, University of Kansas, 2095 Constant Ave, Lawrence, KS, 66047, USA.
| | - Anne Cooper
- Protein Production Group, University of Kansas, Lawrence, KS, 66047, USA
| | - Prem Thapa
- Microscopy and Analytical Imaging Lab, University of Kansas, Lawrence, KS, 66047, USA
| | - Shyamal Choudhari
- Department of Pharmaceutical Chemistry, Macromolecule and Vaccine Stabilization Center, University of Kansas, 2095 Constant Ave, Lawrence, KS, 66047, USA
| | - Fei P Gao
- Protein Production Group, University of Kansas, Lawrence, KS, 66047, USA
| | - David B Volkin
- Department of Pharmaceutical Chemistry, Macromolecule and Vaccine Stabilization Center, University of Kansas, 2095 Constant Ave, Lawrence, KS, 66047, USA
| | - C Russell Middaugh
- Department of Pharmaceutical Chemistry, Macromolecule and Vaccine Stabilization Center, University of Kansas, 2095 Constant Ave, Lawrence, KS, 66047, USA
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37
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Li R, Fu N, Wu Z, Wang Y, Wang Y. Protein aggregation in foam fractionation of bovine serum albumin: Effect of protein concentration. Biochem Eng J 2015. [DOI: 10.1016/j.bej.2015.08.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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38
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He S, Simpson BK, Ngadi MO, Ma Y. In vitro studies of the digestibility of lectin from black turtle bean (Phaseolus vulgaris). Food Chem 2015; 173:397-404. [DOI: 10.1016/j.foodchem.2014.10.045] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Revised: 09/19/2014] [Accepted: 10/08/2014] [Indexed: 11/16/2022]
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39
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Johnson MA, Ray BD, Wassall SR, Petrache HI. Equivalent Isopropanol Concentrations of Aromatic Amino Acids Interactions with Lipid Vesicles. J Membr Biol 2015; 248:695-703. [PMID: 25691267 DOI: 10.1007/s00232-015-9781-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 01/30/2015] [Indexed: 11/26/2022]
Abstract
We show that the interaction of aromatic amino acids with lipid bilayers can be characterized by conventional 1D [Formula: see text]H NMR spectroscopy using reference spectra obtained in isopropanol-d8/D[Formula: see text]O solutions. We demonstrate the utility of this method with three different peptides containing tyrosine, tryptophan, or phenylalanine amino acids in the presence of 1,2-dioleoyl-sn-glycero-3-phosphocholine or 1,2-dioleoyl-sn-glycero-3-phosphoserine lipid membranes. In each case, we determine an equivalent isopropanol concentration (EIC) for each hydrogen site of aromatic groups, in essence constructing a map of the chemical environment. These EIC maps provide information on relative affinities of aromatic side chains for either PC or PS bilayers and also inform on amino acid orientation preference when bound to membranes.
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Affiliation(s)
- Merrell A Johnson
- Department of Physics, Indiana University Purdue University Indianapolis, 402 N Blackford St., Indianapolis, IN, 46202, USA,
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40
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Roque C, Sheung A, Rahman N, Ausar SF. Effect of polyethylene glycol conjugation on conformational and colloidal stability of a monoclonal antibody antigen-binding fragment (Fab'). Mol Pharm 2015; 12:562-75. [PMID: 25548945 DOI: 10.1021/mp500658w] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
We have investigated the effects of site specific "hinge" polyethylene glycol conjugation (PEGylation) on thermal, pH, and colloidal stability of a monoclonal antibody antigen-binding fragment (Fab') using a variety of biophysical techniques. The results obtained by circular dichroism (CD), ultraviolet (UV) absorbance, and fluorescence spectroscopy suggested that the physical stability of the Fab' is maximized at pH 6-7 with no apparent differences due to PEGylation. Temperature-induced aggregation experiments revealed that PEGylation was able to increase the transition temperature, as well as prevent the formation of visible and subvisible aggregates. Statistical comparison of the three-index empirical phase diagram (EPD) revealed significant differences in thermal and pH stability signatures between Fab' and PEG-Fab'. Upon mechanical stress, micro-flow imaging (MFI) and measurement of the optical density at 360 nm showed that the PEG-Fab' had significantly higher resistance to surface-induced aggregation compared to the Fab'. Analysis of the interaction parameter, kD, indicated repulsive intermolecular forces for PEG-Fab' and attractive forces for Fab'. In conclusion, PEGylation appears to protect Fab' against thermal and mechanical stress-induced aggregation, likely due to a steric hindrance mechanism.
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Affiliation(s)
- Cristopher Roque
- Bioprocess Research & Development, Sanofi Pasteur , 1755 Steeles Avenue West, Toronto, Ontario M2R 3T4, Canada
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41
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Czarnecki MA. Resolution enhancement in second-derivative spectra. APPLIED SPECTROSCOPY 2015; 69:67-74. [PMID: 25499557 DOI: 10.1366/14-07568] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Derivative spectroscopy is a powerful tool for the resolution enhancement in infrared, near-infrared, Raman, ultraviolet-visible, nuclear magnetic resonance, electron paramagnetic resonance, and fluorescence spectroscopy. Despite its great significance in analytical chemistry, not all aspects of the applications of this method have been explored as yet. This is the first systematic study of the parameters that influence the resolution enhancement in the second derivative spectra. The derivative spectra were calculated with the Savitzky-Golay method with different window size (5, 15, 25) and polynomial order (2, 4). The results obtained in this work show that the resolution enhancement in the second derivative spectra strongly depends on the data spacing in the original spectra, window size, polynomial order, and peak profile. As shown, the resolution enhancement is related to variations in the width of the peaks upon the differentiation. The present study reveals that in order to maximize the separation of the peaks in the second derivative spectra, the original spectra should be recorded at high resolution and differentiated using a small window size and high polynomial order. However, working with the real spectra one has to compromise between the noise reduction and optimization of the resolution enhancement in the second derivative spectra.
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Affiliation(s)
- Mirosław A Czarnecki
- Faculty of Chemistry, University of Wrocław, F. Joliot-Curie 14, 50-383 Wrocław, Poland
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42
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Fornander LH, Feng B, Beke-Somfai T, Nordén B. UV Transition Moments of Tyrosine. J Phys Chem B 2014; 118:9247-57. [DOI: 10.1021/jp5065352] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Louise H. Fornander
- Department of Chemical and
Biological Engineering, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden
| | - Bobo Feng
- Department of Chemical and
Biological Engineering, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden
| | - Tamás Beke-Somfai
- Department of Chemical and
Biological Engineering, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden
| | - Bengt Nordén
- Department of Chemical and
Biological Engineering, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden
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43
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Li L, Jiang Y, Zhang H, Feng W, Chen B, Tan T. Theoretical and Experimental Studies on Activity of Yarrowia lipolytica Lipase in Methanol/Water Mixtures. J Phys Chem B 2014; 118:1976-83. [DOI: 10.1021/jp404039a] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Lingli Li
- Beijing Key Lab of Bioprocess,
College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China
| | - Yang Jiang
- Beijing Key Lab of Bioprocess,
College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China
| | - Haiyang Zhang
- Beijing Key Lab of Bioprocess,
College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China
| | - Wei Feng
- Beijing Key Lab of Bioprocess,
College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China
| | - Biqiang Chen
- Beijing Key Lab of Bioprocess,
College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China
| | - Tianwei Tan
- Beijing Key Lab of Bioprocess,
College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China
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44
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Gao C, Fan S. Determination of Tyrosine and Tryptophan by Sequential Injection Analysis and Chemiluminescence Detection. ANAL LETT 2013. [DOI: 10.1080/00032719.2013.764532] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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45
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Stability of exenatide in poly(d,l-lactide-co-glycolide) solutions: A simplified investigation on the peptide degradation by the polymer. Eur J Pharm Sci 2013; 50:502-10. [DOI: 10.1016/j.ejps.2013.08.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Revised: 08/10/2013] [Accepted: 08/12/2013] [Indexed: 11/22/2022]
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46
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Hill SC, Pan YL, Williamson C, Santarpia JL, Hill HH. Fluorescence of bioaerosols: mathematical model including primary fluorescing and absorbing molecules in bacteria. OPTICS EXPRESS 2013; 21:22285-313. [PMID: 24104120 DOI: 10.1364/oe.21.022285] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
This paper describes a mathematical model of fluorescent biological particles composed of bacteria, viruses, or proteins. The fluorescent and/or light absorbing molecules included in the model are amino acids (tryptophan, etc.); nucleic acids (DNA, RNA, etc.); coenzymes (nicotinamide adenine dinucleotides, flavins, and vitamins B₆ and K and variants of these); and dipicolinates. The concentrations, absorptivities, and fluorescence quantum yields are estimated from the literature, often with large uncertainties. The bioparticles in the model are spherical and homogeneous. Calculated fluorescence cross sections for particles excited at 266, 280, and 355 nm are compared with measured values from the literature for several bacteria, bacterial spores and albumins. The calculated 266- and 280-nm excited fluorescence is within a factor of 3.2 of the measurements for the vegetative cells and proteins, but overestimates the fluorescence of spores by a factor of 10 or more. This is the first reported modeling of the fluorescence of bioaerosols in which the primary fluorophores and absorbing molecules are included.
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47
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Kamga MH, Woo Lee H, Liu J, Yoon S. Quantification of protein mixture in chromatographic separation using multi-wavelength UV spectra. Biotechnol Prog 2013; 29:664-71. [DOI: 10.1002/btpr.1712] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Revised: 02/01/2013] [Indexed: 11/06/2022]
Affiliation(s)
- Mark-Henry Kamga
- Dept. of Chemical Engineering; University of Massachusetts Lowell; MA 01854
| | - Hae Woo Lee
- Dept. of Chemical Engineering; University of Massachusetts Lowell; MA 01854
| | - Jay Liu
- Dept. of Chemical Engineering; Pukyung National University; Busan Nam-Gu Korea
| | - Seongkyu Yoon
- Dept. of Chemical Engineering; University of Massachusetts Lowell; MA 01854
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48
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Liu W, Nadeau OW, Sage J, Carlson GM. Physicochemical changes in phosphorylase kinase induced by its cationic activator Mg(2+). Protein Sci 2013; 22:444-54. [PMID: 23359552 DOI: 10.1002/pro.2226] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Revised: 01/15/2013] [Accepted: 01/17/2013] [Indexed: 12/12/2022]
Abstract
For over four decades free Mg(2+) ions, that is, those in excess of MgATP, have been reported to affect a wide variety of properties of phosphorylase kinase (PhK), including its affinity for other molecules, proteolysis, chemical crosslinking, phosphorylation, binding to certain monoclonal antibodies, and activity, which is stimulated. Additionally, for over three decades Mg(2+) has been known to act synergistically with Ca(2+) , another divalent activator of PhK, to affect even more properties of the enzyme. During all of this time, however, no study has been performed to determine the overall effects of free Mg(2+) ions on the physical properties of PhK, even though the effects of Ca(2+) ions on PhK's properties are well documented. In this study, changes in the physicochemical properties of PhK induced by Mg(2+) under nonactivating (pH 6.8) and activating (pH 8.2) conditions were investigated by circular dichroism spectroscopy, zeta potential analyses, dynamic light scattering, second derivative UV absorption, negative stain electron microscopy, and differential chemical crosslinking. The effects of the activator Mg(2+) on some of the properties of PhK measured by these techniques were found to be quite different at the two pH values, and displayed both differences and similarities with the effects previously reported to be induced by the activator Ca(2+) (Liu et al., Protein Sci 2008;17:2111-2119). The similarities may reflect the fact that both cations are activators, and foremost among their similarities is the dramatically less negative zeta potential induced by their binding to PhK.
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Affiliation(s)
- Weiya Liu
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, Kansas 66160, USA
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49
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Zhou J, Wang X, Ai T, Cheng X, Guo HY, Teng GX, Mao XY. Preparation and characterization of β-lactoglobulin hydrolysate-iron complexes. J Dairy Sci 2012; 95:4230-6. [PMID: 22818436 DOI: 10.3168/jds.2011-5282] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Accepted: 04/07/2012] [Indexed: 11/19/2022]
Abstract
The purpose of this study was to determine the best preparation condition of β-lactoglobulin hydrolysate-iron complexes and characterize its structural transformation both before and after binding using the UV-visible absorption spectrum, Fluorescence spectrum, and Fourier transform infrared spectroscopy. Results showed that β-lactoglobulin hydrolysates obtained with alcalase after hydrolysis for 6h possessed the highest iron-binding capacity. The highest yield of complexes was obtained when the mass ratio between β-lactoglobulin hydrolysate and Fe(3+) reached 40:1, with the optimal pH value of 7.0. All of the spectra indicated that some sites such as amido bonds transformed during chelation, and nitrogen atoms could chelate with Fe(3+) to form coordinate bonds by offering electron pairs. Therefore, β-lactoglobulin hydrolysate-iron complexes may be good carriers for iron and possess great potential to be used as iron supplements.
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Affiliation(s)
- J Zhou
- Key Laboratory of Functional Dairy of Beijing and Ministry of Education, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
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50
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Xu Y, Xia W, Jiang Q. Aggregation and structural changes of silver carp actomyosin as affected by mild acidification with d-gluconic acid δ-lactone. Food Chem 2012; 134:1005-10. [DOI: 10.1016/j.foodchem.2012.02.216] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2011] [Revised: 02/06/2012] [Accepted: 02/21/2012] [Indexed: 11/30/2022]
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