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Liu F, Sun X, Zhou J, Li J, Chen J, Du G, Zhao X. Efficient biosynthesis of active hemoglobins through enhancing the import of heme in Saccharomyces cerevisiae. FEBS J 2024; 291:3737-3748. [PMID: 38865576 DOI: 10.1111/febs.17199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 02/22/2024] [Accepted: 05/29/2024] [Indexed: 06/14/2024]
Abstract
Hemoglobins, with heme as a cofactor, are functional proteins that have extensive applications in the fields of artificial oxygen carriers and foods. Although Saccharomyces cerevisiae is an ideal host for hemoglobin synthesis, it lacks a suitable transport system to utilize additional heme for active expression of hemoglobins, resulting in the cellular aggregation and degradation of the latter. Here, an effective heme importer, heme-responsive gene 4 (Hrg-4), was selected from six candidates through the comparison of effects on the growth rates of Δhem1 S. cerevisiae strain and the activities of various hemoglobins when supplemented with 5 mg·L-1 exogenous heme. Additionally, to counter the instability of plasmid-based expression and the metabolic burden introduced from overexpressing Hrg-4, a series of hrg-4 integrated strains were constructed and the best engineered strain with five copies of hrg-4 was chosen. We found that this engineered strain was associated with an increased binding rate of heme in monomeric leghemoglobin and multimeric human hemoglobin (76.3% and 16.5%, respectively), as well as an enhanced expression of both hemoglobins (52.8% and 17.0%, respectively). Thus, the engineered strain with improved heme uptake can be used to efficiently synthesize other heme-binding proteins and enzymes in S. cerevisiae.
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Affiliation(s)
- Fan Liu
- Science Center for Future Foods, Jiangnan University, Wuxi, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
- Jiangsu Province Engineering Research Center of Food Synthetic Biotechnology, Jiangnan University, Wuxi, China
- Engineering Research Center of Ministry of Education on Food Synthetic Biotechnology, Jiangnan University, Wuxi, China
| | - Xiaoyan Sun
- Science Center for Future Foods, Jiangnan University, Wuxi, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
- Jiangsu Province Engineering Research Center of Food Synthetic Biotechnology, Jiangnan University, Wuxi, China
- Engineering Research Center of Ministry of Education on Food Synthetic Biotechnology, Jiangnan University, Wuxi, China
| | - Jingwen Zhou
- Science Center for Future Foods, Jiangnan University, Wuxi, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
- Jiangsu Province Engineering Research Center of Food Synthetic Biotechnology, Jiangnan University, Wuxi, China
- Engineering Research Center of Ministry of Education on Food Synthetic Biotechnology, Jiangnan University, Wuxi, China
| | - Jianghua Li
- Science Center for Future Foods, Jiangnan University, Wuxi, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
- Jiangsu Province Engineering Research Center of Food Synthetic Biotechnology, Jiangnan University, Wuxi, China
- Engineering Research Center of Ministry of Education on Food Synthetic Biotechnology, Jiangnan University, Wuxi, China
| | - Jian Chen
- Science Center for Future Foods, Jiangnan University, Wuxi, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
- Jiangsu Province Engineering Research Center of Food Synthetic Biotechnology, Jiangnan University, Wuxi, China
- Engineering Research Center of Ministry of Education on Food Synthetic Biotechnology, Jiangnan University, Wuxi, China
| | - Guocheng Du
- Science Center for Future Foods, Jiangnan University, Wuxi, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
- Jiangsu Province Engineering Research Center of Food Synthetic Biotechnology, Jiangnan University, Wuxi, China
- Engineering Research Center of Ministry of Education on Food Synthetic Biotechnology, Jiangnan University, Wuxi, China
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, China
| | - Xinrui Zhao
- Science Center for Future Foods, Jiangnan University, Wuxi, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
- Jiangsu Province Engineering Research Center of Food Synthetic Biotechnology, Jiangnan University, Wuxi, China
- Engineering Research Center of Ministry of Education on Food Synthetic Biotechnology, Jiangnan University, Wuxi, China
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Kettisen K, Nyblom M, Smeds E, Fago A, Bülow L. Structural and oxidative investigation of a recombinant high-yielding fetal hemoglobin mutant. Front Mol Biosci 2023; 10:1133985. [PMID: 37006610 PMCID: PMC10060959 DOI: 10.3389/fmolb.2023.1133985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 03/01/2023] [Indexed: 03/18/2023] Open
Abstract
Human fetal hemoglobin (HbF) is an attractive starting protein for developing an effective agent for oxygen therapeutics applications. This requires that HbF can be produced in heterologous systems at high levels and in a homogeneous form. The introduction of negative charges on the surface of the α-chain in HbF can enhance the recombinant production yield of a functional protein in Escherichia coli. In this study, we characterized the structural, biophysical, and biological properties of an HbF mutant carrying four additional negative charges on each α-chain (rHbFα4). The 3D structure of the rHbFα4 mutant was solved with X-ray crystallography at 1.6 Å resolution. Apart from enabling a higher yield in recombinant protein production in E. coli, we observed that the normal DNA cleavage activity of the HbF was significantly lowered, with a four-time reduced rate constant for the rHbFα4 mutant. The oxygen-binding properties of the rHbFα4 mutant were identical to the wild-type protein. No significant difference between the wild-type and rHbFα4 was observed for the investigated oxidation rates (autoxidation and H2O2-mediated ferryl formation). However, the ferryl reduction reaction indicated some differences, which appear to be related to the reaction rates linked to the α-chain.
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Affiliation(s)
- Karin Kettisen
- Pure and Applied Biochemistry, Department of Chemistry, Lund University, Lund, Sweden
| | - Maria Nyblom
- Lund Protein Production Platform, Department of Biology, Lund University, Lund, Sweden
| | - Emanuel Smeds
- Infection Medicine, Department of Clinical Sciences, Lund University, Lund, Sweden
- Anesthesiology and Intensive Care, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Angela Fago
- Zoophysiology, Department of Biology, Aarhus University, Aarhus, Denmark
| | - Leif Bülow
- Pure and Applied Biochemistry, Department of Chemistry, Lund University, Lund, Sweden
- *Correspondence: Leif Bülow,
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Hu B, Yu H, Zhou J, Li J, Chen J, Du G, Lee SY, Zhao X. Whole-Cell P450 Biocatalysis Using Engineered Escherichia coli with Fine-Tuned Heme Biosynthesis. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2205580. [PMID: 36526588 PMCID: PMC9951570 DOI: 10.1002/advs.202205580] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 12/05/2022] [Indexed: 05/14/2023]
Abstract
By exploiting versatile P450 enzymes, whole-cell biocatalysis can be performed to synthesize valuable compounds in Escherichia coli. However, the insufficient supply of heme limits the whole-cell P450 biocatalytic activity. Here a strategy for improving intracellular heme biosynthesis to enhance the catalytic efficiencies of P450s is reported. After comparing the effects of improving heme transport and biosynthesis on P450 activities, intracellular heme biosynthesis is optimized through the integrated expression of necessary synthetic genes at proper ratios and the assembly of rate-limiting enzymes using DNA-guided scaffolds. The intracellular heme level is fine-tuned by the combined use of mutated heme-sensitive biosensors and small regulatory RNA systems. The catalytic efficiencies of three different P450s, BM3, sca-2, and CYP105D7, are enhanced through fine-tuning heme biosynthesis for the synthesis of hydroquinone, pravastatin, and 7,3',4'-trihydroxyisoflavone as example products of chemical intermediate, drug, and natural product, respectively. This strategy of fine-tuned heme biosynthesis will be generally useful for developing whole-cell biocatalysts involving hemoproteins.
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Affiliation(s)
- Baodong Hu
- Key Laboratory of Industrial BiotechnologyMinistry of EducationSchool of BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Science Center for Future FoodsJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Jiangsu Province Engineering Research Center of Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Engineering Research Center of Ministry of Education on Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
| | - Haibo Yu
- Key Laboratory of Industrial BiotechnologyMinistry of EducationSchool of BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Science Center for Future FoodsJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Jiangsu Province Engineering Research Center of Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Engineering Research Center of Ministry of Education on Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
| | - Jingwen Zhou
- Key Laboratory of Industrial BiotechnologyMinistry of EducationSchool of BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Science Center for Future FoodsJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Jiangsu Province Engineering Research Center of Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Engineering Research Center of Ministry of Education on Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
| | - Jianghua Li
- Key Laboratory of Industrial BiotechnologyMinistry of EducationSchool of BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Science Center for Future FoodsJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Jiangsu Province Engineering Research Center of Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Engineering Research Center of Ministry of Education on Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
| | - Jian Chen
- Key Laboratory of Industrial BiotechnologyMinistry of EducationSchool of BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Science Center for Future FoodsJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Jiangsu Province Engineering Research Center of Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Engineering Research Center of Ministry of Education on Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
| | - Guocheng Du
- Key Laboratory of Industrial BiotechnologyMinistry of EducationSchool of BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Science Center for Future FoodsJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Jiangsu Province Engineering Research Center of Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Engineering Research Center of Ministry of Education on Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Key Laboratory of Carbohydrate Chemistry and BiotechnologyMinistry of EducationJiangnan University1800 Lihu RoadWuxiJiangsu214122China
| | - Sang Yup Lee
- Metabolic and Biomolecular Engineering National Research LaboratoryDepartment of Chemical and Biomolecular Engineering (BK21 Plus Program)BioProcess Engineering Research CenterBioinformatics Research Center, and Institute for the BioCenturyKorea Advanced Institute of Science and Technology (KAIST)DaejeonYuseong‐gu34141Republic of Korea
| | - Xinrui Zhao
- Key Laboratory of Industrial BiotechnologyMinistry of EducationSchool of BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Science Center for Future FoodsJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Jiangsu Province Engineering Research Center of Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Engineering Research Center of Ministry of Education on Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
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Faggiano S, Ronda L, Bruno S, Abbruzzetti S, Viappiani C, Bettati S, Mozzarelli A. From hemoglobin allostery to hemoglobin-based oxygen carriers. Mol Aspects Med 2021; 84:101050. [PMID: 34776270 DOI: 10.1016/j.mam.2021.101050] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 11/05/2021] [Accepted: 11/05/2021] [Indexed: 12/18/2022]
Abstract
Hemoglobin (Hb) plays its vital role through structural and functional properties evolutionarily optimized to work within red blood cells, i.e., the tetrameric assembly, well-defined oxygen affinity, positive cooperativity, and heterotropic allosteric regulation by protons, chloride and 2,3-diphosphoglycerate. Outside red blood cells, the Hb tetramer dissociates into dimers, which exhibit high oxygen affinity and neither cooperativity nor allosteric regulation. They are prone to extravasate, thus scavenging endothelial NO and causing hypertension, and cause nephrotoxicity. In addition, they are more prone to autoxidation, generating radicals. The need to overcome the adverse effects associated with cell-free Hb has always been a major hurdle in the development of substitutes of allogeneic blood transfusions for all clinical situations where blood is unavailable or cannot be used due to, for example, religious objections. This class of therapeutics, indicated as hemoglobin-based oxygen carriers (HBOCs), is formed by genetically and/or chemically modified Hbs. Many efforts were devoted to the exploitation of the wealth of biochemical and biophysical information available on Hb structure, function, and dynamics to design safe HBOCs, overcoming the negative effects of free plasma Hb. Unfortunately, so far, no HBOC has been approved by FDA and EMA, except for compassionate use. However, the unmet clinical needs that triggered intensive investigations more than fifty years ago are still awaiting an answer. Recently, HBOCs "repositioning" has led to their successful application in organ perfusion fluids.
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Affiliation(s)
- Serena Faggiano
- Department of Food and Drug, University of Parma, Parma, Italy; Institute of Biophysics, National Research Council, Pisa, Italy
| | - Luca Ronda
- Institute of Biophysics, National Research Council, Pisa, Italy; Department of Medicine and Surgery, University of Parma, Parma, Italy
| | - Stefano Bruno
- Department of Food and Drug, University of Parma, Parma, Italy
| | - Stefania Abbruzzetti
- Department of Mathematical, Physical and Computer Sciences, University of Parma, Parma, Italy
| | - Cristiano Viappiani
- Department of Mathematical, Physical and Computer Sciences, University of Parma, Parma, Italy
| | - Stefano Bettati
- Institute of Biophysics, National Research Council, Pisa, Italy; Department of Medicine and Surgery, University of Parma, Parma, Italy; National Institute of Biostructures and Biosystems, Rome, Italy
| | - Andrea Mozzarelli
- Department of Food and Drug, University of Parma, Parma, Italy; Institute of Biophysics, National Research Council, Pisa, Italy.
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5
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Optimization of Hydroperoxide Lyase Production for Recombinant Lipoxygenase Pathway Cascade Application. Catalysts 2021. [DOI: 10.3390/catal11101201] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Cis-3-hexenal and its more stable isomer, trans-2-hexenal, are highly valued chemicals used in the food and perfume industries. They are produced by the plant lipoxygenase pathway, where two enzymes, lipoxygenase (LOX) and hydroperoxide lyase (HPL), are involved. However, the application of this pathway is limited, especially due to the instability of HPL. This enzyme belongs to the cytochrome P450 enzyme family and needs heme as a prosthetic group. Its synthesis must be effectively performed by a host organism in order to produce an active protein. In this work, Pseudomonas aeruginosa LOX was expressed in Escherichia coli BL21(DE3), and whole cells were used for the synthesis of 13(S)-hydroperoxy-(Z,E,Z)-9,11,15-octadecatrienoic acid (13-HPOT) as a substrate for HPL. Expression of Psidium guajava HPL was carried out by recombinant E. coli JM109(DE3) in autoinduction media, and the influence of the addition of heme precursors δ-ALA and FeII+ was studied. Specific activity of whole cells expressing HPL was measured by the direct use of a synthesized 13-HPOT solution (2.94 mM of total hydroperoxides, 75.35% of 13-HPOT (2.22 mM)) and increased 2.6-fold (from 61.78 U·mg−1 to 159.95 U·mg−1) with the addition of 1 mM FeII+ to the autoinduction media. Productivity and activity were further enhanced by an increase in the expression temperature, and a total of 3.30·105 U·dm−3 of culture media was produced in the optimized process.
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Kettisen K, Bülow L. Introducing Negatively Charged Residues on the Surface of Fetal Hemoglobin Improves Yields in Escherichia coli. Front Bioeng Biotechnol 2021; 9:721794. [PMID: 34552916 PMCID: PMC8450383 DOI: 10.3389/fbioe.2021.721794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Accepted: 08/20/2021] [Indexed: 11/14/2022] Open
Abstract
Fetal hemoglobin (HbF) has been developed into an important alternative protein for oxygen therapeutics. Such applications require extensive amounts of proteins, which only can be achieved via recombinant means. However, the expression of vertebrate hemoglobins in heterologous hosts is far from trivial. There are several issues that need to be dealt with. These include, among others, the solubility of the globin chains, equimolar expression of the globin chains, and access to high levels of free heme. In this study, we examined the impact of introducing negative charges on the surface of HbF. Three different HbF mutants were examined, carrying four additional negative charges on the α-subunit (rHbFα4), two additional negative charges on the γ-subunit (rHbFγ2) or a combination of these (rHbFα4/γ2). The increase in negative surface charge in these HbF mutants required the development of an alternate initial capture step in the downstream purification procedures. For the rHbFα4 mutant, we achieved a significantly enhanced yield of purified HbF with no apparent adverse effects on Hb functionality. However, the presence of non-functional Hb portions in the rHbFγ2 and rHbFα4/γ2 samples reduced the yields significantly for those mutants and indicated an imbalanced expression/association of globin chains. Furthermore, the autoxidation studies indicated that the rHbFγ2 and rHbFα4/γ2 mutants also were less oxidatively stable than rHbFα4 and wt rHbF. The study further verified the need for an improved flask culture protocol by optimizing cultivation parameters to enable yield-improving qualities of surface-located mutations.
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Affiliation(s)
- Karin Kettisen
- Division of Pure and Applied Biochemistry, Department of Chemistry, Lund University, Lund, Sweden
| | - Leif Bülow
- Division of Pure and Applied Biochemistry, Department of Chemistry, Lund University, Lund, Sweden
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7
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Characterization of Two Hydrogen Peroxide Resistant Peroxidases from Rhodococcus opacus 1CP. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11177941] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The dye-decolorizing peroxidases (DyP) are a family of heme-dependent enzymes present on a broad spectrum of microorganisms. While the natural function of these enzymes is not fully understood, their capacity to degrade highly contaminant pigments such as azo dyes or anthraquinones make them excellent candidates for applications in bioremediation and organic synthesis. In this work, two novel DyP peroxidases from the organism Rhodococcus opacus 1CP (DypA and DypB) were cloned and expressed in Escherichia coli. The enzymes were purified and biochemically characterized. The activities of the two DyPs via 2,2′-azino-bis [3-ethylbenzthiazoline-6-sulphonic acid] (ABTS) assay and against Reactive Blue 5 were assessed and optimized. Results showed varying trends for DypA and DypB. Remarkably, these enzymes presented a particularly high tolerance towards H2O2, retaining its activities at about 10 mM H2O2 for DypA and about 4.9 mM H2O2 for DypB.
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8
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Kanagarajan S, Carlsson MLR, Chakane S, Kettisen K, Smeds E, Kumar R, Ortenlöf N, Gram M, Åkerström B, Bülow L, Zhu LH. Production of functional human fetal hemoglobin in Nicotiana benthamiana for development of hemoglobin-based oxygen carriers. Int J Biol Macromol 2021; 184:955-966. [PMID: 34153360 DOI: 10.1016/j.ijbiomac.2021.06.102] [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: 03/13/2021] [Revised: 06/11/2021] [Accepted: 06/13/2021] [Indexed: 10/21/2022]
Abstract
Hemoglobin-based oxygen carriers have long been pursued to meet clinical needs by using native hemoglobin (Hb) from human or animal blood, or recombinantly produced Hb, but the development has been impeded by safety and toxicity issues. Herewith we report the successful production of human fetal hemoglobin (HbF) in Nicotiana benthamiana through Agrobacterium tumefaciens-mediated transient expression. HbF is a heterotetrameric protein composed of two identical α- and two identical γ-subunits, held together by hydrophobic interactions, hydrogen bonds, and salt bridges. In our study, the α- and γ-subunits of HbF were fused in order to stabilize the α-subunits and facilitate balanced expression of α- and γ-subunits in N. benthamiana. Efficient extraction and purification methods enabled production of the recombinantly fused endotoxin-free HbF (rfHbF) in high quantity and quality. The transiently expressed rfHbF protein was identified by SDS-PAGE, Western blot and liquid chromatography-tandem mass spectrometry analyses. The purified rfHbF possessed structural and functional properties similar to native HbF, which were confirmed by biophysical, biochemical, and in vivo animal studies. The results demonstrate a high potential of plant expression systems in producing Hb products for use as blood substitutes.
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Affiliation(s)
- Selvaraju Kanagarajan
- Department of Plant Breeding, Swedish University of Agricultural Sciences, Lomma, Sweden
| | - Magnus L R Carlsson
- Department of Plant Breeding, Swedish University of Agricultural Sciences, Lomma, Sweden
| | - Sandeep Chakane
- Division of Pure and Applied Biochemistry, Department of Chemistry, Lund University, Lund, Sweden
| | - Karin Kettisen
- Division of Pure and Applied Biochemistry, Department of Chemistry, Lund University, Lund, Sweden
| | - Emanuel Smeds
- Division of Infection Medicine, Department of Clinical Sciences in Lund, Lund University, Lund, Sweden
| | - Ranjeet Kumar
- Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Niklas Ortenlöf
- Division of Infection Medicine, Department of Clinical Sciences in Lund, Lund University, Lund, Sweden
| | - Magnus Gram
- Pediatrics, Department of Clinical Sciences Lund, Lund University, Skåne University Hospital, Lund, Sweden
| | - Bo Åkerström
- Division of Infection Medicine, Department of Clinical Sciences in Lund, Lund University, Lund, Sweden
| | - Leif Bülow
- Division of Pure and Applied Biochemistry, Department of Chemistry, Lund University, Lund, Sweden
| | - Li-Hua Zhu
- Department of Plant Breeding, Swedish University of Agricultural Sciences, Lomma, Sweden.
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9
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Ishchuk OP, Frost AT, Muñiz-Paredes F, Matsumoto S, Laforge N, Eriksson NL, Martínez JL, Petranovic D. Improved production of human hemoglobin in yeast by engineering hemoglobin degradation. Metab Eng 2021; 66:259-267. [PMID: 33984513 DOI: 10.1016/j.ymben.2021.05.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 04/09/2021] [Accepted: 05/04/2021] [Indexed: 12/23/2022]
Abstract
With the increasing demand for blood transfusions, the production of human hemoglobin (Hb) from sustainable sources is increasingly studied. Microbial production is an attractive option, as it may provide a cheap, safe, and reliable source of this protein. To increase the production of human hemoglobin by the yeast Saccharomyces cerevisiae, the degradation of Hb was reduced through several approaches. The deletion of the genes HMX1 (encoding heme oxygenase), VPS10 (encoding receptor for vacuolar proteases), PEP4 (encoding vacuolar proteinase A), ROX1 (encoding heme-dependent repressor of hypoxic genes) and the overexpression of the HEM3 (encoding porphobilinogen deaminase) and the AHSP (encoding human alpha-hemoglobin-stabilizing protein) genes - these changes reduced heme and Hb degradation and improved heme and Hb production. The reduced hemoglobin degradation was validated by a bilirubin biosensor. During glucose fermentation, the engineered strains produced 18% of intracellular Hb relative to the total yeast protein, which is the highest production of human hemoglobin reported in yeast. This increased hemoglobin production was accompanied with an increased oxygen consumption rate and an increased glycerol yield, which (we speculate) is the yeast's response to rebalance its NADH levels under conditions of oxygen limitation and increased protein-production.
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Affiliation(s)
- Olena P Ishchuk
- Department of Biology and Biological Engineering, Systems and Synthetic Biology, Chalmers University of Technology, SE41296, Gothenburg, Sweden.
| | - August T Frost
- Department of Biotechnology and Biomedicine, Section for Synthetic Biology, Technical University of Denmark, DK-2800, Kgs. Lyngby, Denmark
| | - Facundo Muñiz-Paredes
- Department of Biology and Biological Engineering, Systems and Synthetic Biology, Chalmers University of Technology, SE41296, Gothenburg, Sweden
| | - Saki Matsumoto
- Department of Biology and Biological Engineering, Systems and Synthetic Biology, Chalmers University of Technology, SE41296, Gothenburg, Sweden
| | - Nathalie Laforge
- Department of Biology and Biological Engineering, Systems and Synthetic Biology, Chalmers University of Technology, SE41296, Gothenburg, Sweden
| | - Nélida Leiva Eriksson
- Department of Chemistry, Division of Biotechnology, Lund University, 221 00, Lund, Sweden
| | - José L Martínez
- Department of Biology and Biological Engineering, Systems and Synthetic Biology, Chalmers University of Technology, SE41296, Gothenburg, Sweden; Department of Biotechnology and Biomedicine, Section for Synthetic Biology, Technical University of Denmark, DK-2800, Kgs. Lyngby, Denmark
| | - Dina Petranovic
- Department of Biology and Biological Engineering, Systems and Synthetic Biology, Chalmers University of Technology, SE41296, Gothenburg, Sweden; Novo Nordisk Foundation Centre for Biosustainability, Chalmers University of Technology, SE41296, Gothenburg, Sweden.
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10
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Zhao X, Zhou J, Du G, Chen J. Recent Advances in the Microbial Synthesis of Hemoglobin. Trends Biotechnol 2020; 39:286-297. [PMID: 32912649 DOI: 10.1016/j.tibtech.2020.08.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 07/27/2020] [Accepted: 08/11/2020] [Indexed: 01/08/2023]
Abstract
Hemoglobin is a cofactor-containing protein with heme that plays important roles in transporting and storing oxygen. Hemoglobins have been widely applied as acellular oxygen carriers, bioavailable iron-supplying agents, and food-grade coloring and flavoring agents. To meet increasing demands and overcome the drawbacks of chemical extraction, the biosynthesis of hemoglobin has become an attractive alternative. Several hemoglobins have recently been synthesized by various microorganisms through metabolic engineering and synthetic biology. In this review, we summarize the novel strategies that have been used to biosynthesize hemoglobin. These strategies can also serve as references for producing other heme-binding proteins.
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Affiliation(s)
- Xinrui Zhao
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu 214122, China; Science Center for Future Foods, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Jingwen Zhou
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu 214122, China; Science Center for Future Foods, Jiangnan University, Wuxi, Jiangsu 214122, China; National Engineering Laboratory of Cereal Fermentation Technology, Jiangnan University, Wuxi, Jiangsu 214122, China.
| | - Guocheng Du
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu 214122, China; Science Center for Future Foods, Jiangnan University, Wuxi, Jiangsu 214122, China; Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Jian Chen
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu 214122, China; Science Center for Future Foods, Jiangnan University, Wuxi, Jiangsu 214122, China; National Engineering Laboratory of Cereal Fermentation Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
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11
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The Interplay between Molten Globules and Heme Disassociation Defines Human Hemoglobin Disassembly. Biophys J 2020; 118:1381-1400. [PMID: 32075750 DOI: 10.1016/j.bpj.2020.01.031] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 01/22/2020] [Accepted: 01/27/2020] [Indexed: 12/12/2022] Open
Abstract
Hemoglobin functions as a tetrameric oxygen transport protein, with each subunit containing a heme cofactor. Its denaturation, either in vivo or in vitro, involves autoxidation to methemoglobin, followed by cofactor loss and globin unfolding. We have proposed a global disassembly scheme for human methemoglobin, linking hemin (ferric protoporphyrin IX) disassociation and apoprotein unfolding pathways. The model is based on the evaluation of circular dichroism and visible absorbance measurements of guanidine-hydrochloride-induced disassembly of methemoglobin and previous measurements of apohemoglobin unfolding. The populations of holointermediates and equilibrium disassembly parameters were estimated quantitatively for adult and fetal hemoglobins. The key stages are characterized by hexacoordinated hemichrome intermediates, which are important for preventing hemin disassociation from partially unfolded, molten globular species during early disassembly and late-stage assembly events. Both unfolding experiments and independent small angle x-ray scattering measurements demonstrate that heme disassociation leads to the loss of tetrameric structural integrity. Our model predicts that after autoxidation, dimeric and monomeric hemichrome intermediates occur along the disassembly pathway inside red cells, where the hemoglobin concentration is very high. This prediction suggests why misassembled hemoglobins often get trapped as hemichromes that accumulate into insoluble Heinz bodies in the red cells of patients with unstable hemoglobinopathies. These Heinz bodies become deposited on the cell membranes and can lead to hemolysis. Alternatively, when acellular hemoglobin is diluted into blood plasma after red cell lysis, the disassembly pathway appears to be dominated by early hemin disassociation events, which leads to the generation of higher fractions of unfolded apo subunits and free hemin, which are known to damage the integrity of blood vessel walls. Thus, our model provides explanations of the pathophysiology of hemoglobinopathies and other disease states associated with unstable globins and red cell lysis and also insights into the factors governing hemoglobin assembly during erythropoiesis.
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12
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Olson JS. Lessons Learned from 50 Years of Hemoglobin Research: Unstirred and Cell-Free Layers, Electrostatics, Baseball Gloves, and Molten Globules. Antioxid Redox Signal 2020; 32:228-246. [PMID: 31530172 PMCID: PMC6948003 DOI: 10.1089/ars.2019.7876] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Significance: Over the past 50 years, the mechanisms for O2 storage and transport have been determined quantitatively on distance scales from millimeters to tenths of nanometers and timescales from seconds to picoseconds. Recent Advances: In this review, I have described four key conclusions from work done by my group and our close colleagues. (i) O2 uptake by mammalian red cells is limited by diffusion through unstirred water layers adjacent to the cell surface and across cell-free layers adjacent to vessel walls. (ii) In most vertebrates, hemoglobins (Hbs) and myoglobins (Mbs), the distal histidine at the E7 helical position donates a strong hydrogen bond to bound O2, which selectively enhances O2 affinity, prevents carbon monoxide poisoning, and markedly slows autoxidation. (iii) O2 binding to mammalian Hbs and Mbs occurs by migration of the ligand through a channel created by upward rotation of the His(E7) side chain, capture in the empty space of the distal pocket, and then coordination with the ferroprotoporphyrin IX (heme) iron atom. (iv) The assembly of Mbs and Hbs occurs by formation of molten globule intermediates, in which the N- and C-terminal helices have almost fully formed secondary structures, but the heme pockets are disordered and followed by high-affinity binding of heme. Critical Issues: These conclusions indicate that there are often compromises between O2 transport function, holoprotein stability, and the efficiency of assembly. Future Directions: However, the biochemical mechanisms underlying these conclusions provide the framework for understanding globin evolution in greater detail and for engineering more efficient and stable globins.
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Affiliation(s)
- John S Olson
- BioSciences Department, Rice University, Houston, Texas
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Pires IS, Belcher DA, Hickey R, Miller C, Badu‐Tawiah AK, Baek JH, Buehler PW, Palmer AF. Novel manufacturing method for producing apohemoglobin and its biophysical properties. Biotechnol Bioeng 2019; 117:125-145. [DOI: 10.1002/bit.27193] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 06/08/2019] [Accepted: 10/11/2019] [Indexed: 12/25/2022]
Affiliation(s)
- Ivan S. Pires
- William G. Lowrie Department of Chemical and Biomolecular EngineeringThe Ohio State University Columbus Ohio
| | - Donald A. Belcher
- William G. Lowrie Department of Chemical and Biomolecular EngineeringThe Ohio State University Columbus Ohio
| | - Richard Hickey
- William G. Lowrie Department of Chemical and Biomolecular EngineeringThe Ohio State University Columbus Ohio
| | - Colbert Miller
- Department of Chemistry and BiochemistryThe Ohio State University Columbus Ohio
| | | | - Jin Hyen Baek
- Laboratory of Biochemistry and Vascular Biology, Division of Hematology, Center for Biologics Evaluation and ResearchFood and Drug Administration Silver Spring Maryland
| | - Paul W. Buehler
- Laboratory of Biochemistry and Vascular Biology, Division of Hematology, Center for Biologics Evaluation and ResearchFood and Drug Administration Silver Spring Maryland
| | - Andre F. Palmer
- William G. Lowrie Department of Chemical and Biomolecular EngineeringThe Ohio State University Columbus Ohio
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14
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Users Guide to Pitfalls and Lessons Learned About HBOC-201 During Clinical Trials, Expanded Access, and Clinical Use in 1,701 Patients. Shock 2019; 52:92-99. [DOI: 10.1097/shk.0000000000001038] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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15
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Yadav R, Scott EE. Endogenous insertion of non-native metalloporphyrins into human membrane cytochrome P450 enzymes. J Biol Chem 2018; 293:16623-16634. [PMID: 30217815 DOI: 10.1074/jbc.ra118.005417] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 09/13/2018] [Indexed: 11/06/2022] Open
Abstract
Human cytochrome P450 enzymes are membrane-bound heme-containing monooxygenases. As is the case for many heme-containing enzymes, substitution of the metal in the center of the heme can be useful for mechanistic and structural studies of P450 enzymes. For many heme proteins, the iron protoporphyrin prosthetic group can be extracted and replaced with protoporphyrin containing another metal, but human membrane P450 enzymes are not stable enough for this approach. The method reported herein was developed to endogenously produce human membrane P450 proteins with a nonnative metal in the heme. This approach involved coexpression of the P450 of interest, a heme uptake system, and a chaperone in Escherichia coli growing in iron-depleted minimal medium supplemented with the desired trans-metallated protoporphyrin. Using the steroidogenic P450 enzymes CYP17A1 and CYP21A2 and the drug-metabolizing CYP3A4, we demonstrate that this approach can be used with several human P450 enzymes and several different metals, resulting in fully folded proteins appropriate for mechanistic, functional, and structural studies including solution NMR.
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Affiliation(s)
- Rahul Yadav
- From the Departments of Medicinal Chemistry and
| | - Emily E Scott
- From the Departments of Medicinal Chemistry and .,Pharmacology, University of Michigan, Ann Arbor, Michigan 48109
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16
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Comparison of the oxidative reactivity of recombinant fetal and adult human hemoglobin: implications for the design of hemoglobin-based oxygen carriers. Biosci Rep 2018; 38:BSR20180370. [PMID: 29802155 PMCID: PMC6028758 DOI: 10.1042/bsr20180370] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Revised: 05/22/2018] [Accepted: 05/23/2018] [Indexed: 12/21/2022] Open
Abstract
Hemoglobin (Hb)-based oxygen carriers (HBOCs) have been engineered to replace or augment the oxygen carrying capacity of erythrocytes. However, clinical results have generally been disappointing, in part due to the intrinsic oxidative toxicity of Hb. The most common HBOC starting material is adult human or bovine Hb. However, it has been suggested that fetal Hb may offer advantages due to decreased oxidative reactivity. Large-scale manufacturing of HBOC will likely and ultimately require recombinant sources of human proteins. We, therefore, directly compared the functional properties and oxidative reactivity of recombinant fetal (rHbF) and recombinant adult (rHbA) Hb. rHbA and rHbF produced similar yields of purified functional protein. No differences were seen in the two proteins in: autoxidation rate; the rate of hydrogen peroxide reaction; NO scavenging dioxygenase activity; and the NO producing nitrite reductase activity. The rHbF protein was: less damaged by low levels of hydrogen peroxide; less damaging when added to human umbilical vein endothelial cells (HUVEC) in the ferric form; and had a slower rate of intrinsic heme loss. The rHbA protein was: more readily reducible by plasma antioxidants such as ascorbate in both the reactive ferryl and ferric states; less readily damaged by lipid peroxides; and less damaging to phosphatidylcholine liposomes. In conclusion in terms of oxidative reactivity, there are advantages and disadvantages to the use of rHbA or rHbF as the basis for an effective HBOC.
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Meng F, Kassa T, Jana S, Wood F, Zhang X, Jia Y, D’Agnillo F, Alayash AI. Comprehensive Biochemical and Biophysical Characterization of Hemoglobin-Based Oxygen Carrier Therapeutics: All HBOCs Are Not Created Equally. Bioconjug Chem 2018; 29:1560-1575. [DOI: 10.1021/acs.bioconjchem.8b00093] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Fantao Meng
- Laboratory of Biochemistry and Vascular Biology, Division of Blood Components and Devices, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland 20993, United States
| | - Tigist Kassa
- Laboratory of Biochemistry and Vascular Biology, Division of Blood Components and Devices, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland 20993, United States
| | - Sirsendu Jana
- Laboratory of Biochemistry and Vascular Biology, Division of Blood Components and Devices, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland 20993, United States
| | - Francine Wood
- Laboratory of Biochemistry and Vascular Biology, Division of Blood Components and Devices, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland 20993, United States
| | - Xiaoyuan Zhang
- Laboratory of Biochemistry and Vascular Biology, Division of Blood Components and Devices, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland 20993, United States
| | - Yiping Jia
- Laboratory of Biochemistry and Vascular Biology, Division of Blood Components and Devices, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland 20993, United States
| | - Felice D’Agnillo
- Laboratory of Biochemistry and Vascular Biology, Division of Blood Components and Devices, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland 20993, United States
| | - Abdu I. Alayash
- Laboratory of Biochemistry and Vascular Biology, Division of Blood Components and Devices, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland 20993, United States
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18
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Engineering oxidative stability in human hemoglobin based on the Hb providence (βK82D) mutation and genetic cross-linking. Biochem J 2017; 474:4171-4192. [PMID: 29070524 DOI: 10.1042/bcj20170491] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 10/04/2017] [Accepted: 10/23/2017] [Indexed: 12/24/2022]
Abstract
Previous work suggested that hemoglobin (Hb) tetramer formation slows autoxidation and hemin loss and that the naturally occurring mutant, Hb Providence (HbProv; βK82D), is much more resistant to degradation by H2O2 We have examined systematically the effects of genetic cross-linking of Hb tetramers with and without the HbProv mutation on autoxidation, hemin loss, and reactions with H2O2, using native HbA and various wild-type recombinant Hbs as controls. Genetically cross-linked Hb Presbyterian (βN108K) was also examined as an example of a low oxygen affinity tetramer. Our conclusions are: (a) at low concentrations, all the cross-linked tetramers show smaller rates of autoxidation and hemin loss than HbA, which can dissociate into much less stable dimers and (b) the HbProv βK82D mutation confers more resistance to degradation by H2O2, by markedly inhibiting oxidation of the β93 cysteine side chain, particularly in cross-linked tetramers and even in the presence of the destabilizing Hb Presbyterian mutation. These results show that cross-linking and the βK82D mutation do enhance the resistance of Hb to oxidative degradation, a critical element in the design of a safe and effective oxygen therapeutic.
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Strader MB, Alayash AI. Exploring Oxidative Reactions in Hemoglobin Variants Using Mass Spectrometry: Lessons for Engineering Oxidatively Stable Oxygen Therapeutics. Antioxid Redox Signal 2017; 26:777-793. [PMID: 27626360 PMCID: PMC5421604 DOI: 10.1089/ars.2016.6805] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Revised: 09/09/2016] [Accepted: 09/12/2016] [Indexed: 01/29/2023]
Abstract
SIGNIFICANCE Worldwide demand has driven the development of hemoglobin (Hb)-based oxygen carriers (HBOCs) as potential acellular oxygen therapeutics. HBOCs have the potential to provide an oxygen bridge to patients and minimize current problems associated with supply and storage of donated blood. However, to date, safety and efficacy issues have hampered the approval of viable HBOCs in the United States. These previous efforts have underscored the need for a better molecular understanding of toxicity to design safe and oxidatively stable HBOCs. Recent Advances: High-resolution accurate mass (HRAM) mass spectrometry (MS) has recently become a versatile tool in characterizing oxidative post-translational modifications that occur in Hb. When integrated with other analytical techniques, HRAM data have been invaluable in providing mechanistic insight into the extent of oxidative modification by quantifying oxidation in amino acids near the reactive heme or at specific "oxidative hotspots." CRITICAL ISSUES In addition to providing a deeper understanding of Hb oxidative toxicity, HRAM MS studies are currently being used toward developing suitable HBOCs using a "two-prong" strategy that involves (i) understanding the mechanism of Hb toxicity by evaluating mutant Hbs identified in patients with hemoglobinopathies and (ii) utilizing this information toward designing against (or for) these reactions in acellular oxygen therapeutics that will result in oxidatively stable protein. FUTURE DIRECTIONS Future HRAM studies are aimed at fully characterizing engineered candidate HBOCs to determine the most oxidatively stable protein while retaining oxygen carrying function in vivo. Antioxid. Redox Signal. 26, 777-793.
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Affiliation(s)
- Michael Brad Strader
- Laboratory of Biochemistry and Vascular Biology, Center for Biologics Evaluation and Research , Food and Drug Administration, Silver Spring, Maryland
| | - Abdu I Alayash
- Laboratory of Biochemistry and Vascular Biology, Center for Biologics Evaluation and Research , Food and Drug Administration, Silver Spring, Maryland
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20
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Abstract
Removal of heme from human hemoglobin (Hb) results in formation of an apoglobin heterodimer. Titration of this apodimer with guanidine hydrochloride (GdnHCl) leads to biphasic unfolding curves indicating two distinct steps. Initially, the heme pocket unfolds and generates a dimeric intermediate in which ∼50% of the original helicity is lost, but the α1β1 interface is still intact. At higher GdnHCl concentrations, this intermediate dissociates into unfolded monomers. This structural interpretation was verified by comparing GdnHCl titrations for adult human hemoglobin A (HbA), recombinant fetal human hemoglobin (HbF), recombinant Hb cross-linked with a single glycine linker between the α chains, and recombinant Hbs with apolar heme pocket mutations that markedly stabilize native conformations in both subunits. The first phase of apoHb unfolding is independent of protein concentration, little affected by genetic cross-linking, but significantly shifted toward higher GdnHCl concentrations by the stabilizing distal pocket mutations. The second phase depends on protein concentration and is shifted to higher GdnHCl concentrations by genetic cross-linking. This model for apoHb unfolding allowed us to quantitate subtle differences in stability between apoHbA and apoHbF, which suggest that the β and γ heme pockets have similar stabilities, whereas the α1γ1 interface is more resistant to dissociation than the α1β1 interface.
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Affiliation(s)
- Premila P Samuel
- Department of BioSciences and ‡Department of Chemistry, Rice University , Houston, Texas 77251, United States
| | - William C Ou
- Department of BioSciences and ‡Department of Chemistry, Rice University , Houston, Texas 77251, United States
| | - George N Phillips
- Department of BioSciences and ‡Department of Chemistry, Rice University , Houston, Texas 77251, United States
| | - John S Olson
- Department of BioSciences and ‡Department of Chemistry, Rice University , Houston, Texas 77251, United States
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21
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Alayash AI. Hemoglobin-Based Blood Substitutes and the Treatment of Sickle Cell Disease: More Harm than Help? Biomolecules 2017; 7:biom7010002. [PMID: 28054978 PMCID: PMC5372714 DOI: 10.3390/biom7010002] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Revised: 12/20/2016] [Accepted: 12/26/2016] [Indexed: 01/17/2023] Open
Abstract
Intense efforts have been made by both industry and academia over the last three decades to produce viable hemoglobin (Hb)-based oxygen carriers (HBOCs), also known as “blood substitutes”. Human trials conducted so far by several manufactures in a variety of clinical indications, including trauma, and elective surgeries have failed and no product has gained the Food and Drug Administration approval for human use. Safety concerns due to frequent incidences of hemodynamic, cardiac events, and even death led to the termination of some of these trials. Several second generation HBOC products that have been chemically and/or genetically modified (or in some cases ligated with carbon monoxide (CO)) found a new clinical application in conditions as complex as sickle cell disease (SCD). By virtue of higher oxygen affinity (P50) (R-state), and smaller size, HBOCs may be able to reach the microvasculature unload of oxygen to reverse the cycles of sickling/unsickling of the deoxy-sickle cell Hb (HbS) (T-state), thus preventing vaso-occlusion, a central event in SCD pathophysiology. However, biochemically, it is thought that outside the red blood cell (due to frequent hemolysis), free HbS or infused HBOCs are capable of interfering with a number of oxidative and signaling pathways and may, thus, negate any benefit that HBOCs may provide. This review discusses the advantages and disadvantages of using HBOCs in SCD.
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Affiliation(s)
- Abdu I Alayash
- Laboratory of Biochemistry and Vascular Biology, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, MD 20993, USA.
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22
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Moradi S, Jahanian-Najafabadi A, Roudkenar MH. Artificial Blood Substitutes: First Steps on the Long Route to Clinical Utility. Clin Med Insights Blood Disord 2016; 9:33-41. [PMID: 27812292 PMCID: PMC5084831 DOI: 10.4137/cmbd.s38461] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 09/14/2016] [Accepted: 09/27/2016] [Indexed: 11/28/2022]
Abstract
The 21st century is challenging for human beings. Increased population growth, population aging, generation of new infectious agents, and natural disasters are some threatening factors for the current state of blood transfusion. However, it seems that science and technology not only could overcome these challenges but also would turn many human dreams to reality in this regard. Scientists believe that one of the future evolutionary innovations could be artificial blood substitutes that might pave the way to a new era in transfusion medicine. In this review, recent status and progresses in artificial blood substitutes, focusing on red blood cells substitutes, are summarized. In addition, steps taken toward the development of artificial blood technology and some of their promises and hurdles will be highlighted. However, it must be noted that artificial blood is still at the preliminary stages of development, and to fulfill this dream, ie, to routinely transfuse artificial blood into human vessels, we still have to strengthen our knowledge and be patient.
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Affiliation(s)
- Samira Moradi
- Blood Transfusion Research Center, High Institute for Research and Education in Transfusion Medicine, Tehran, Iran
| | - Ali Jahanian-Najafabadi
- Department of Pharmaceutical Biotechnology, and Isfahan Pharmaceutical Sciences Research Center, School of Pharmacy, Isfahan University of Medical Sciences and Health Services, Isfahan, Iran
| | - Mehryar Habibi Roudkenar
- Department of Medical Biotechnology, Laboratory of Microbiology and Immunology of Infectious Diseases, Paramedicine Faculty, Guilan University of Medical Sciences Rasht, Iran
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Paciello A, Amalfitano G, Garziano A, Urciuolo F, Netti PA. Hemoglobin-Conjugated Gelatin Microsphere as a Smart Oxygen Releasing Biomaterial. Adv Healthc Mater 2016; 5:2655-2666. [PMID: 27594116 DOI: 10.1002/adhm.201600559] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Revised: 07/28/2016] [Indexed: 12/12/2022]
Abstract
In this study, a novel micrometric biomaterial acting as a cyclic oxygen releasing system is designed. Human hemoglobin (Hb) is conjugated to the surface of gelatin microspheres (GM) to produce gelatin hemoglobin oxygen depot (G-HbOD). G-HbOD is obtained by means of two different conjugation strategies. The degree of conjugation of GM surfaces in terms of free amino groups by using HPLC is first evaluated. By following the strategy A (G-HbOD_A), Hb is conjugated to GM by means of the formation of a polyurethane linker. In the strategy B (G-HbOD_B) the conjugation occurs via amide bound formation. Physical and morphological differences between G-HbOD_A and G-HbOD_B are investigated by means of Fourier Transform Infrared Spectroscopy (FTIR), Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES), Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). Differences in oxygen uptake/release kinetics are found depending on the conjugation strategy and it is proved that G-HbOD works under repeated cycles in microfluidic chip. Moreover, G-HbOD is also able to work as oxygen depot in the early stages of 3D cell cultures.
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Affiliation(s)
- Antonio Paciello
- Center for Advanced Biomaterials for Health Care@CRIB Istituto Italiano di Tecnologia; Largo Barsanti e Matteucci n. 53 80125 Napoli Italy
- Interdisciplinary Research Centre on Biomaterials (CRIB); University of Naples Federico II; P.le Tecchio 80 80125 Napoli Italy
| | - Giuseppe Amalfitano
- Center for Advanced Biomaterials for Health Care@CRIB Istituto Italiano di Tecnologia; Largo Barsanti e Matteucci n. 53 80125 Napoli Italy
- Interdisciplinary Research Centre on Biomaterials (CRIB); University of Naples Federico II; P.le Tecchio 80 80125 Napoli Italy
| | - Alessandro Garziano
- Center for Advanced Biomaterials for Health Care@CRIB Istituto Italiano di Tecnologia; Largo Barsanti e Matteucci n. 53 80125 Napoli Italy
- Interdisciplinary Research Centre on Biomaterials (CRIB); University of Naples Federico II; P.le Tecchio 80 80125 Napoli Italy
| | - Francesco Urciuolo
- Center for Advanced Biomaterials for Health Care@CRIB Istituto Italiano di Tecnologia; Largo Barsanti e Matteucci n. 53 80125 Napoli Italy
| | - Paolo A. Netti
- Center for Advanced Biomaterials for Health Care@CRIB Istituto Italiano di Tecnologia; Largo Barsanti e Matteucci n. 53 80125 Napoli Italy
- Interdisciplinary Research Centre on Biomaterials (CRIB); University of Naples Federico II; P.le Tecchio 80 80125 Napoli Italy
- Department of Chemical; Materials and Industrial Production Engineering (DICMAPI); University of Napoli Federico II; P.le Tecchio 80 80125 Napoli Italy
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Eggenreich B, Willim M, Wurm DJ, Herwig C, Spadiut O. Production strategies for active heme-containing peroxidases from E. coli inclusion bodies - a review. BIOTECHNOLOGY REPORTS (AMSTERDAM, NETHERLANDS) 2016; 10:75-83. [PMID: 28352527 PMCID: PMC5040872 DOI: 10.1016/j.btre.2016.03.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Revised: 03/18/2016] [Accepted: 03/19/2016] [Indexed: 01/28/2023]
Abstract
Heme-containing peroxidases are frequently used in medical applications. However, these enzymes are still extracted from their native source, which leads to inadequate yields and a mixture of isoenzymes differing in glycosylation which limits subsequent enzyme applications. Thus, recombinant production of these enzymes in Escherichia coli is a reasonable alternative. Even though production yields are high, the product is frequently found as protein aggregates called inclusion bodies (IBs). These IBs have to be solubilized and laboriously refolded to obtain active enzyme. Unfortunately, refolding yields are still very low making the recombinant production of these enzymes in E. coli not competitive. Motivated by the high importance of that enzyme class, this review aims at providing a comprehensive summary of state-of-the-art strategies to obtain active peroxidases from IBs. Additionally, various refolding techniques, which have not yet been used for this enzyme class, are discussed to show alternative and potentially more efficient ways to obtain active peroxidases from E. coli.
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Affiliation(s)
- Britta Eggenreich
- Vienna University of Technology, Institute of Chemical Engineering, Research Area Biochemical Engineering, Vienna, Austria
- Christian Doppler Laboratory for Mechanistic and Physiological Methods for Improved Bioprocesses, Institute of Chemical Engineering, Vienna University of Technology, Vienna, Austria
| | - Melissa Willim
- Vienna University of Technology, Institute of Chemical Engineering, Research Area Biochemical Engineering, Vienna, Austria
| | - David Johannes Wurm
- Vienna University of Technology, Institute of Chemical Engineering, Research Area Biochemical Engineering, Vienna, Austria
| | - Christoph Herwig
- Vienna University of Technology, Institute of Chemical Engineering, Research Area Biochemical Engineering, Vienna, Austria
- Christian Doppler Laboratory for Mechanistic and Physiological Methods for Improved Bioprocesses, Institute of Chemical Engineering, Vienna University of Technology, Vienna, Austria
| | - Oliver Spadiut
- Vienna University of Technology, Institute of Chemical Engineering, Research Area Biochemical Engineering, Vienna, Austria
- Christian Doppler Laboratory for Mechanistic and Physiological Methods for Improved Bioprocesses, Institute of Chemical Engineering, Vienna University of Technology, Vienna, Austria
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25
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Oxidative instability of hemoglobin E (β26 Glu→Lys) is increased in the presence of free α subunits and reversed by α-hemoglobin stabilizing protein (AHSP): Relevance to HbE/β-thalassemia. Redox Biol 2016; 8:363-74. [PMID: 26995402 PMCID: PMC4804395 DOI: 10.1016/j.redox.2016.03.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Revised: 03/04/2016] [Accepted: 03/09/2016] [Indexed: 01/24/2023] Open
Abstract
When adding peroxide (H2O2), β subunits of hemoglobin (Hb) bear the burden of oxidative changes due in part to the direct oxidation of its Cys93. The presence of unpaired α subunits within red cells and/or co-inheritance of another β subunit mutant, HbE (β26 Glu→Lys) have been implicated in the pathogenesis and severity of β thalassemia. We have found that although both HbA and HbE autoxidize at initially comparable rates, HbE loses heme at a rate almost 2 fold higher than HbA due to unfolding of the protein. Using mass spectrometry and the spin trap, DMPO, we were able to quantify irreversible oxidization of βCys93 to reflect oxidative instability of β subunits. In the presence of free α subunits and H2O2, both HbA and HbE showed βCys93 oxidation which increased with higher H2O2 concentrations. In the presence of Alpha-hemoglobin stabilizing protein (AHSP), which stabilizes the α-subunit in a redox inactive hexacoordinate conformation (thus unable to undergo the redox ferric/ferryl transition), Cys93 oxidation was substantially reduced in both proteins. These experiments establish two important features that may have relevance to the mechanistic understanding of these two inherited hemoglobinopathies, i.e. HbE/β thalassemia: First, a persistent ferryl/ferryl radical in HbE is more damaging to its own β subunit (i.e., βCys93) than HbA. Secondly, in the presence of excess free α-subunit and under the same oxidative conditions, these events are substantially increased for HbE compared to HbA, and may therefore create an oxidative milieu affecting the already unstable HbE. A compromised redox ferric/ferryl cycle promotes oxidative instability in hemoglobin E (HbE). The presence of unmatched alpha subunits aggravates oxidative instability of HbE. Alpha-hemoglobin stabilizing protein (AHSP) reverses alpha subunit destabilizing effects on HbE.
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Ramzi AB, Hyeon JE, Han SO. Improved catalytic activities of a dye-decolorizing peroxidase (DyP) by overexpression of ALA and heme biosynthesis genes in Escherichia coli. Process Biochem 2015. [DOI: 10.1016/j.procbio.2015.05.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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27
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Samuel PP, Smith LP, Phillips GN, Olson JS. Apoglobin Stability Is the Major Factor Governing both Cell-free and in Vivo Expression of Holomyoglobin. J Biol Chem 2015. [PMID: 26205820 DOI: 10.1074/jbc.m115.672204] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Expression levels in animal muscle tissues and in Escherichia coli vary widely for naturally occurring mammalian myoglobins (Mb). To explore this variation, we developed an in vitro transcription and wheat germ extract-based translation assay to examine quantitatively the factors that govern expression of holoMb. We constructed a library of naturally occurring Mbs from two terrestrial and four deep-diving aquatic mammals and three distal histidine mutants designed to enhance apoglobin stability but decrease hemin affinity. A strong linear correlation is observed between cell-free expression levels of holo-metMb variants and their corresponding apoglobin stabilities, which were measured independently by guanidine HCl-induced unfolding titrations using purified proteins. In contrast, there is little dependence of expression on hemin affinity. Our results confirm quantitatively that deep diving mammals have highly stable Mbs that express to higher levels in animal myocytes, E. coli, and the wheat germ cell-free system than Mbs from terrestrial mammals. Our theoretical analyses show that the rate of aggregation of unfolded apoMb is very large, and as a result, the key factor for high level expression of holoMb, and presumably other heme proteins, is an ultra high fraction of folded, native apoglobin that is capable of rapidly binding hemin. This fraction is determined by the overall equilibrium folding constant and not hemin affinity. These results also demonstrate that the cell-free transcription/translation system can be used as a high throughput platform to screen for apoglobin stability without the need to generate large amounts of protein for in vitro unfolding measurements.
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Affiliation(s)
| | | | - George N Phillips
- From BioSciences at Rice and Department of Chemistry, Rice University, Houston, Texas 77005
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Role of α-globin H helix in the building of tetrameric human hemoglobin: interaction with α-hemoglobin stabilizing protein (AHSP) and heme molecule. PLoS One 2014; 9:e111395. [PMID: 25369055 PMCID: PMC4219717 DOI: 10.1371/journal.pone.0111395] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 09/23/2014] [Indexed: 11/25/2022] Open
Abstract
Alpha-Hemoglobin Stabilizing Protein (AHSP) binds to α-hemoglobin (α-Hb) or α-globin and maintains it in a soluble state until its association with the β-Hb chain partner to form Hb tetramers. AHSP specifically recognizes the G and H helices of α-Hb. To investigate the degree of interaction of the various regions of the α-globin H helix with AHSP, this interface was studied by stepwise elimination of regions of the α-globin H helix: five truncated α-Hbs α-Hb1-138, α-Hb1-134, α-Hb1-126, α-Hb1-123, α-Hb1-117 were co-expressed with AHSP as two glutathione-S-transferase (GST) fusion proteins. SDS-PAGE and Western Blot analysis revealed that the level of expression of each truncated α-Hb was similar to that of the wild type α-Hb except the shortest protein α-Hb1-117 which displayed a decreased expression. While truncated GST-α-Hb1-138 and GST-α-Hb1-134 were normally soluble; the shorter globins GST-α-Hb1-126 and GST-α-Hb1-117 were obtained in very low quantities, and the truncated GST-α-Hb1-123 provided the least material. Absorbance and fluorescence studies of complexes showed that the truncated α-Hb1-134 and shorter forms led to modified absorption spectra together with an increased fluorescence emission. This attests that shortening the H helix leads to a lower affinity of the α-globin for the heme. Upon addition of β-Hb, the increase in fluorescence indicates the replacement of AHSP by β-Hb. The CO binding kinetics of different truncated AHSPWT/α-Hb complexes showed that these Hbs were not functionally normal in terms of the allosteric transition. The N-terminal part of the H helix is primordial for interaction with AHSP and C-terminal part for interaction with heme, both features being required for stability of α-globin chain.
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Kabbua T, Anwised P, Boonmee A, Subedi BP, Pierce BS, Thammasirirak S. Autoinduction, purification, and characterization of soluble α-globin chains of crocodile (Crocodylus siamensis) hemoglobin in Escherichia coli. Protein Expr Purif 2014; 103:56-63. [DOI: 10.1016/j.pep.2014.08.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Revised: 08/19/2014] [Accepted: 08/20/2014] [Indexed: 01/30/2023]
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Martínez JL, Liu L, Petranovic D, Nielsen J. Engineering the oxygen sensing regulation results in an enhanced recombinant human hemoglobin production bySaccharomyces cerevisiae. Biotechnol Bioeng 2014; 112:181-8. [DOI: 10.1002/bit.25347] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Revised: 07/15/2014] [Accepted: 07/15/2014] [Indexed: 12/20/2022]
Affiliation(s)
- José L. Martínez
- Department of Chemical and Biological Engineering; Novo Nordisk Foundation Center for Biosustainability; Chalmers University of Technology; Kemivägen 10 SE-41296 Göteborg Sweden
| | - Lifang Liu
- Department of Chemical and Biological Engineering; Novo Nordisk Foundation Center for Biosustainability; Chalmers University of Technology; Kemivägen 10 SE-41296 Göteborg Sweden
| | - Dina Petranovic
- Department of Chemical and Biological Engineering; Novo Nordisk Foundation Center for Biosustainability; Chalmers University of Technology; Kemivägen 10 SE-41296 Göteborg Sweden
| | - Jens Nielsen
- Department of Chemical and Biological Engineering; Novo Nordisk Foundation Center for Biosustainability; Chalmers University of Technology; Kemivägen 10 SE-41296 Göteborg Sweden
- Novo Nordisk Foundation Center for Biosustainability; Technical University of Denmark; Fremtidsvej 3 DK-2970 Hørsholm Denmark
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Li B, Qi Y, He S, Wang Y, Xie Z, Jing X, Huang Y. Asymmetric copolymer vesicles to serve as a hemoglobin vector for ischemia therapy. Biomater Sci 2014; 2:1254-1261. [DOI: 10.1039/c4bm00123k] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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32
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Liu L, Martínez JL, Liu Z, Petranovic D, Nielsen J. Balanced globin protein expression and heme biosynthesis improve production of human hemoglobin in Saccharomyces cerevisiae. Metab Eng 2014; 21:9-16. [DOI: 10.1016/j.ymben.2013.10.010] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2012] [Revised: 08/19/2013] [Accepted: 10/04/2013] [Indexed: 11/30/2022]
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Varnado CL, Mollan TL, Birukou I, Smith BJ, Henderson DP, Olson JS. Development of recombinant hemoglobin-based oxygen carriers. Antioxid Redox Signal 2013; 18:2314-28. [PMID: 23025383 PMCID: PMC3638513 DOI: 10.1089/ars.2012.4917] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2012] [Revised: 09/23/2012] [Accepted: 10/01/2012] [Indexed: 12/27/2022]
Abstract
SIGNIFICANCE The worldwide blood shortage has generated a significant demand for alternatives to whole blood and packed red blood cells for use in transfusion therapy. One such alternative involves the use of acellular recombinant hemoglobin (Hb) as an oxygen carrier. RECENT ADVANCES Large amounts of recombinant human Hb can be expressed and purified from transgenic Escherichia coli. The physiological suitability of this material can be enhanced using protein-engineering strategies to address specific efficacy and toxicity issues. Mutagenesis of Hb can (i) adjust dioxygen affinity over a 100-fold range, (ii) reduce nitric oxide (NO) scavenging over 30-fold without compromising dioxygen binding, (iii) slow the rate of autooxidation, (iv) slow the rate of hemin loss, (v) impede subunit dissociation, and (vi) diminish irreversible subunit denaturation. Recombinant Hb production is potentially unlimited and readily subjected to current good manufacturing practices, but may be restricted by cost. Acellular Hb-based O(2) carriers have superior shelf-life compared to red blood cells, are universally compatible, and provide an alternative for patients for whom no other alternative blood products are available or acceptable. CRITICAL ISSUES Remaining objectives include increasing Hb stability, mitigating iron-catalyzed and iron-centered oxidative reactivity, lowering the rate of hemin loss, and lowering the costs of expression and purification. Although many mutations and chemical modifications have been proposed to address these issues, the precise ensemble of mutations has not yet been identified. FUTURE DIRECTIONS Future studies are aimed at selecting various combinations of mutations that can reduce NO scavenging, autooxidation, oxidative degradation, and denaturation without compromising O(2) delivery, and then investigating their suitability and safety in vivo.
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Affiliation(s)
| | - Todd L. Mollan
- Center for Biologics Evaluation and Research, Division of Hematology, United States Food and Drug Administration, Bethesda, Maryland
| | - Ivan Birukou
- Department of Biochemistry, Duke University, Durham, North Carolina
| | - Bryan J.Z. Smith
- Department of Biology, The University of Texas of the Permian Basin, Odessa, Texas
| | - Douglas P. Henderson
- Department of Biology, The University of Texas of the Permian Basin, Odessa, Texas
| | - John S. Olson
- Department of Biochemistry & Cell Biology, Rice University, Houston, Texas
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Propylbenzmethylation at Val-1(α) markedly increases the tetramer stability of the PEGylated hemoglobin: A comparison with propylation at Val-1(α). Biochim Biophys Acta Gen Subj 2012; 1820:2044-51. [DOI: 10.1016/j.bbagen.2012.09.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2012] [Revised: 09/15/2012] [Accepted: 09/20/2012] [Indexed: 11/19/2022]
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35
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Krishna Kumar K, Jacques DA, Pishchany G, Caradoc-Davies T, Spirig T, Malmirchegini GR, Langley DB, Dickson CF, Mackay JP, Clubb RT, Skaar EP, Guss JM, Gell DA. Structural basis for hemoglobin capture by Staphylococcus aureus cell-surface protein, IsdH. J Biol Chem 2011; 286:38439-38447. [PMID: 21917915 PMCID: PMC3207429 DOI: 10.1074/jbc.m111.287300] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2011] [Revised: 08/16/2011] [Indexed: 02/02/2023] Open
Abstract
Pathogens must steal iron from their hosts to establish infection. In mammals, hemoglobin (Hb) represents the largest reservoir of iron, and pathogens express Hb-binding proteins to access this source. Here, we show how one of the commonest and most significant human pathogens, Staphylococcus aureus, captures Hb as the first step of an iron-scavenging pathway. The x-ray crystal structure of Hb bound to a domain from the Isd (iron-regulated surface determinant) protein, IsdH, is the first structure of a Hb capture complex to be determined. Surface mutations in Hb that reduce binding to the Hb-receptor limit the capacity of S. aureus to utilize Hb as an iron source, suggesting that Hb sequence is a factor in host susceptibility to infection. The demonstration that pathogens make highly specific recognition complexes with Hb raises the possibility of developing inhibitors of Hb binding as antibacterial agents.
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Affiliation(s)
- Kaavya Krishna Kumar
- School of Molecular Bioscience, University of Sydney, New South Wales 2006, Australia
| | - David A Jacques
- School of Molecular Bioscience, University of Sydney, New South Wales 2006, Australia
| | - Gleb Pishchany
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical School, Nashville, Tennessee 37232
| | | | - Thomas Spirig
- Department of Chemistry and Biochemistry, UCLA, Los Angeles, California 90095
| | | | - David B Langley
- School of Molecular Bioscience, University of Sydney, New South Wales 2006, Australia
| | - Claire F Dickson
- Menzies Research Institute, University of Tasmania, Tasmania 7000, Australia
| | - Joel P Mackay
- School of Molecular Bioscience, University of Sydney, New South Wales 2006, Australia
| | - Robert T Clubb
- Department of Chemistry and Biochemistry, UCLA, Los Angeles, California 90095
| | - Eric P Skaar
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical School, Nashville, Tennessee 37232
| | - J Mitchell Guss
- School of Molecular Bioscience, University of Sydney, New South Wales 2006, Australia
| | - David A Gell
- Menzies Research Institute, University of Tasmania, Tasmania 7000, Australia.
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36
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Abraham B, Hicks W, Jia Y, Baek JH, Miller JL, Alayash AI. Isolated Hb Providence β82Asn and β82Asp fractions are more stable than native HbA(0) under oxidative stress conditions. Biochemistry 2011; 50:9752-66. [PMID: 21977904 DOI: 10.1021/bi200876e] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
We have previously shown that hydrogen peroxide (H(2)O(2)) triggers irreversible oxidation of amino acids exclusive to the β-chains of purified human hemoglobin (HbAo). However, it is not clear, whether α- or β-subunit Hb variants exhibit different oxidative resistance to H(2)O(2) when compared to their native HbAo. Hb Providence contains two β-subunit variants with single amino acid mutations at βLys82→Asp (βK82D) and at βLys82→Asn (βK82N) positions and binds oxygen at lower affinity than wild type HbA. We have separated Hb Providence into its 3 component fractions, and contrasted oxidative reactions of its β-mutant fractions with HbAo. Relative to HbAo, both βK82N and βK82D fractions showed similar autoxidation kinetics and similar initial oxidation reaction rates with H(2)O(2). However, a more profound pattern of changes was seen in HbAo than in the two Providence fractions. The structural changes in HbAo include a collapse of β-subunits, and α-α dimer formation in the presence of excess H(2)O(2). Mass spectrometric and amino acid analysis revealed that βCys93 and βCys112 were oxidized in the HbAo fraction, consistent with oxidative pathways driven by a ferrylHb and its protein radical. These amino acids were oxidized at a lesser extent in βK82D fraction. While the 3 isolated components of Hb Providence exhibited similar ligand binding and oxidation reaction kinetics, the variant fractions were more effective in consuming H(2)O(2) and safely internalizing radicals through the ferric/ferryl pseudoperoxidase cycle.
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Affiliation(s)
- Bindu Abraham
- Laboratory of Biochemistry and Vascular Biology, Division of Hematology, Center for Biologics Evaluation and Research, US Food and Drug Administration, Bethesda, Maryland 20892, United States
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37
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Development of a method to produce hemoglobin in a bioreactor culture of Escherichia coli BL21(DE3) transformed with a plasmid containing Plesiomonas shigelloides heme transport genes and modified human hemoglobin genes. Appl Environ Microbiol 2011; 77:6703-5. [PMID: 21803893 DOI: 10.1128/aem.05712-11] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We describe a method for production of recombinant human hemoglobin by Escherichia coli grown in a bioreactor. E. coli BL21(DE3) transformed with a plasmid containing hemoglobin genes and Plesiomonas shigelloides heme transport genes reached a cell dry weight of 83.64 g/liter and produced 11.92 g/liter of hemoglobin in clarified lysates.
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38
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Makino T, Skretas G, Georgiou G. Strain engineering for improved expression of recombinant proteins in bacteria. Microb Cell Fact 2011; 10:32. [PMID: 21569582 PMCID: PMC3120638 DOI: 10.1186/1475-2859-10-32] [Citation(s) in RCA: 139] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2011] [Accepted: 05/14/2011] [Indexed: 01/17/2023] Open
Abstract
Protein expression in Escherichia coli represents the most facile approach for the preparation of non-glycosylated proteins for analytical and preparative purposes. So far, the optimization of recombinant expression has largely remained a matter of trial and error and has relied upon varying parameters, such as expression vector, media composition, growth temperature and chaperone co-expression. Recently several new approaches for the genome-scale engineering of E. coli to enhance recombinant protein expression have been developed. These methodologies now enable the generation of optimized E. coli expression strains in a manner analogous to metabolic engineering for the synthesis of low-molecular-weight compounds. In this review, we provide an overview of strain engineering approaches useful for enhancing the expression of hard-to-produce proteins, including heterologous membrane proteins.
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Affiliation(s)
- Tomohiro Makino
- Department of Chemical Engineering, The University of Texas at Austin, 78712, USA
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39
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Szlachcic A, Zakrzewska M, Otlewski J. Longer action means better drug: tuning up protein therapeutics. Biotechnol Adv 2011; 29:436-41. [PMID: 21443940 DOI: 10.1016/j.biotechadv.2011.03.005] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2010] [Revised: 03/08/2011] [Accepted: 03/15/2011] [Indexed: 11/24/2022]
Abstract
An increasing number of proteins are currently available on the market as therapeutics and this branch of the pharmaceutical industry will expand substantially during the coming years. As many diseases result from dysfunction of proteins forming multicomponent complexes, protein drugs with their inherent high specificity and affinity seem to be optimal medical agents. On the other hand, proteins are often highly instable and sensitive to degradation, which questions their applicability as effective therapeutics. Therefore, redesign and engineering of proteins is usually a required step in the present day drug development. Several approaches have been applied to optimize the protein properties central to their pharmaceutical use. This review focuses on different strategies that improve two crucial factors influencing protein drug efficiency: protein stability and its in vivo half-life. We provide examples of successful genetic and chemical modifications applied in the design of effective protein therapeutics.
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Affiliation(s)
- Anna Szlachcic
- Faculty of Biotechnology, University of Wroclaw, Tamka 2, 50-137 Wroclaw, Poland
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40
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Faggiano S, Bruno S, Ronda L, Pizzonia P, Pioselli B, Mozzarelli A. Modulation of expression and polymerization of hemoglobin Polytaur, a potential blood substitute. Arch Biochem Biophys 2011; 505:42-7. [DOI: 10.1016/j.abb.2010.09.027] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2010] [Revised: 09/27/2010] [Accepted: 09/27/2010] [Indexed: 11/25/2022]
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41
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Haemoglobin-based oxygen carriers: research and reality towards an alternative to blood transfusions. BLOOD TRANSFUSION = TRASFUSIONE DEL SANGUE 2010; 8 Suppl 3:s59-68. [PMID: 20606751 DOI: 10.2450/2010.010s] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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42
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Culbertson DS, Olson JS. Role of heme in the unfolding and assembly of myoglobin. Biochemistry 2010; 49:6052-63. [PMID: 20540498 DOI: 10.1021/bi1006942] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The unfolding of wild-type holomyoglobin in the ferric state (metMb) appears to be a simple two-state process, even though hemichrome spectra are often observed and apoMb denaturation involves an intermediate. To resolve these discrepancies, we measured GuHCl-induced, equilibrium unfolding of five sperm whale metMb variants, which were selected to examine the relative importance of apoglobin stability and hemin affinity. Combined analysis of CD, Trp fluorescence, and Soret absorbance titration curves for all the variants requires a six-state mechanism containing native (N), intermediate (I), and unfolded (U) states of apoMb and their hemin-bound counterparts, NH (holoMb), IH, and UH, respectively. The unfolding parameters for the apoMbs were obtained in independent experiments and then fixed in the analysis of the holoprotein data, where only the affinities of the apoglobin states for hemin were allowed to vary. This cofactor binding analysis applies generally to all globins and led to three specific conclusions. (1) The stability of holo-metMb is determined primarily by the high affinity (K(d) approximately 10(-13) M) of native apoMb (N) for hemin. (2) The partially unfolded intermediate with hemin bound (IH) has a hemichrome spectrum indicative of a bis-histidyl axial coordination and is seen clearly when the stability of the N state or its affinity for hemin is reduced. (3) Although the affinity of the intermediate for hemin (K(d) approximately 10(-11) M) is approximately 100-fold lower than that for the native state, free hemin can bind to it and promote the assembly of the holoprotein.
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Affiliation(s)
- David S Culbertson
- Department of Biochemistry and Cell Biology and W. M. Keck Center for Computational Biology, Rice University, Houston, Texas 77005, USA
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43
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Nadithe V, Bae YH. Synthesis and characterization of hemoglobin conjugates with antioxidant enzymes via poly(ethylene glycol) cross-linker (Hb-SOD-CAT) for protection from free radical stress. Int J Biol Macromol 2010; 47:603-13. [PMID: 20723561 DOI: 10.1016/j.ijbiomac.2010.08.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2010] [Revised: 08/09/2010] [Accepted: 08/10/2010] [Indexed: 12/27/2022]
Abstract
Hemoglobin (Hb) conjugated with the antioxidant enzymes (SOD and CAT), by employing dicarboxymethylated poly(ethylene glycol), was designed for protection of hemoglobin against free radicals. In this study, the conjugation process was confirmed by employing SDS-PAGE and SEC techniques. The average molecular weight of the conjugates was estimated to be around 1000 kDa. The enzymatic activities of the SOD and CAT in the conjugates (Hb-SOD-CAT) after conjugation were found to retain greater than 70% and 90% of the original bioactivity. Results show that antioxidant enzymes helped minimize methemoglobin (non-carrier of oxygen) formation during the conjugation process and also during storage at 4°C over a period of 1 month. In summary, the optimized (1:10 Hb/PEG) crosslinked conjugates with antioxidant enzymes showed protective properties from severe free radical stresses when incubated with hydrogen peroxide (0.1 and 1 mM) and xanthine (1 mM)/xanthine oxidase (10 and 20 mU/ml) system.
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Affiliation(s)
- Venkatareddy Nadithe
- Department of Pharmaceutics and Pharmaceutical Chemistry, University of Utah, 421 Wakara Way, Suite 315, Salt Lake City, UT 84108, USA
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44
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Leu SJ, Lee YC, Shih NY, Huang IJ, Liu KJ, Lu HF, Huang SY, Yang YY. Generation and characterization of anti-alpha-enolase single-chain antibodies in chicken. Vet Immunol Immunopathol 2010; 137:251-60. [PMID: 20655599 PMCID: PMC7112641 DOI: 10.1016/j.vetimm.2010.06.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2009] [Revised: 04/20/2010] [Accepted: 06/02/2010] [Indexed: 11/07/2022]
Abstract
It was previously reported that up-regulation of α-enolase protein was detected in 65% of patients with non-small cell lung cancers (NSCLC). Moreover, a high titer of anti-α-enolase antibodies was developed in a smaller proportion (7.4%) of these patients than in non-tumor-associated patients and healthy subjects. In the present study, we characterized polyclonal and single-chain variable fragment (scFv) anti-α-enolase antibodies from immunized chickens. The E. coli-derived recombinant α-enolase protein was purified to its high homogenicity as verified by SDS-PAGE. After the 4th immunization, a high titer of specific polyclonal anti-α-enolase antibodies was elicited in immunized chickens and specifically recognized the purified human α-enolase antigen as determined by Western blot and ELISA. The expressed heavy and light chain variable genes (VH and VL) were isolated from spleen B cells and amplified to construct phage antibody libraries containing scFv molecules. After four rounds of panning selection, the scFv antibodies of randomly chosen clones were expressed and their binding specificity to α-enolase protein was verified using competitive ELISA, flow cytometry and immunofluorescence staining. Nucleotide sequence analysis from 10 α-enolase binding clones showed that 3 (30%) clones used identical heavy and light genes for scFv antibody expression, as represented by EnL5. Notably, amino acid changes in complementarity-determining regions (CDRs) were more frequently observed than those in framework regions (FRs) in all clones, indicating a strong affinity selection through mutations. All together, it is believed that these polyclonal and scFv IgY antibodies may be helpful in the development of molecular diagnostic and therapeutic agents for lung cancers in the future.
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Affiliation(s)
- Sy-Jye Leu
- Department of Microbiology and Immunology, School of Medicine, Taipei Medical University, Taipei 110, Taiwan
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45
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Sudhamsu J, Kabir M, Airola MV, Patel BA, Yeh SR, Rousseau DL, Crane BR. Co-expression of ferrochelatase allows for complete heme incorporation into recombinant proteins produced in E. coli. Protein Expr Purif 2010; 73:78-82. [PMID: 20303407 DOI: 10.1016/j.pep.2010.03.010] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2010] [Accepted: 03/13/2010] [Indexed: 10/19/2022]
Abstract
Over-expression of heme binding proteins in Escherichia coli often results in sub-optimal heme incorporation and the amount of heme-bound protein produced usually varies with the protein of interest. Complete heme incorporation is important for biochemical characterization, spectroscopy, structural studies, and for the production of homogeneous commercial proteins with high activity. We have determined that recombinant proteins expressed in E. coli often contain less than a full complement of heme because they rather are partially incorporated with free-base porphyrin. Porphyrin-incorporated proteins have similar spectral characteristics as the desired heme-loaded targets, and thus are difficult to detect, even in purified samples. We present a straightforward and inexpensive solution to this problem that involves the co-expression of native ferrochelatase with the protein of interest. The method is shown to be effective for proteins that contain either Cys- or His-ligated hemes.
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Affiliation(s)
- Jawahar Sudhamsu
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA
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46
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Mollan TL, Yu X, Weiss MJ, Olson JS. The role of alpha-hemoglobin stabilizing protein in redox chemistry, denaturation, and hemoglobin assembly. Antioxid Redox Signal 2010; 12:219-31. [PMID: 19659437 PMCID: PMC2821148 DOI: 10.1089/ars.2009.2780] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Hemoglobin biosynthesis in erythrocyte precursors involves several steps. The correct ratios and concentrations of normal alpha (alpha) and beta (beta) globin proteins must be expressed; apoproteins must be folded correctly; heme must be synthesized and incorporated into these globins rapidly; and the individual alpha and beta subunits must be rapidly and correctly assembled into heterotetramers. These events occur on a large scale in vivo, and dysregulation causes serious clinical disorders such as thalassemia syndromes. Recent work has implicated a conserved erythroid protein known as Alpha-Hemoglobin Stabilizing Protein (AHSP) as a participant in these events. Current evidence suggests that AHSP enhances alpha subunit stability and diminishes its participation in harmful redox chemistry. There is also evidence that AHSP facilitates one or more early-stage post-translational hemoglobin biosynthetic events. In this review, recent experimental results are discussed in light of several current models describing globin subunit folding, heme uptake, assembly, and denaturation during hemoglobin synthesis. Particular attention is devoted to molecular interactions with AHSP that relate to alpha chain oxidation and the ability of alpha chains to associate with partner beta chains.
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Affiliation(s)
- Todd L Mollan
- Department of Biochemistry and Cell Biology, Rice University, Houston, Texas 77251-1892, USA
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Silverman TA, Weiskopf RB. Hemoglobin-based oxygen carriers: current status and future directions. Transfusion 2009; 49:2495-515. [DOI: 10.1111/j.1537-2995.2009.02356.x] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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48
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Grey M, Yainoy S, Prachayasittikul V, Bülow L. A superoxide dismutase-human hemoglobin fusion protein showing enhanced antioxidative properties. FEBS J 2009; 276:6195-203. [DOI: 10.1111/j.1742-4658.2009.07323.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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49
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Asmundson AL, Taber AM, van der Walde A, Lin DH, Olson JS, Anthony-Cahill SJ. Coexpression of human alpha- and circularly permuted beta-globins yields a hemoglobin with normal R state but modified T state properties. Biochemistry 2009; 48:5456-65. [PMID: 19397368 DOI: 10.1021/bi900216p] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
For the first time, a circularly permuted human beta-globin (cpbeta) has been coexpressed with human alpha-globin in bacterial cells and shown to associate to form alpha-cpbeta hemoglobin in solution. Flash photolysis studies of alpha-cpbeta show markedly biphasic CO and O(2) kinetics with the amplitudes for the fast association phases being dominant due the presence of large amounts of high-affinity liganded hemoglobin dimers. Extensive dimerization of liganded but not deoxygenated alpha-cpbeta was observed by gel chromatography. The rate constants for O(2) and CO binding to the R state forms of alpha-cpbeta are almost identical to those of native HbA (k'(R(CO)) approximately 5.0 microM(-1) s(-1); k'(R(O(2))) approximately 50 microM(-1) s(-1)), and the rate of O(2) dissociation from fully oxygenated alpha-cpbeta is also very similar to that observed for HbA (k(R(O(2))) approximately 21-28 s(-1)). When the equilibrium deoxyHb form of alpha-cpbeta is reacted with CO in rapid mixing experiments, the observed time courses are monophasic and the observed bimolecular association rate constant is approximately 1.0 microM(-1) s(-1), which is intermediate between the R state rate measured in partial photolysis experiments (approximately 5 microM(-1) s(-1)) and that observed for T state deoxyHbA (k'(T(CO)) approximately 0.1 to 0.2 microM(-1) s(-1)). Thus the deoxygenated permutated beta subunits generate an intermediate, higher affinity, deoxyHb quaternary state. This conclusion is supported by equilibrium oxygen binding measurements in which alpha-cpbeta exhibits a P(50) of approximately 1.5 mmHg and a low n-value (approximately 1.3) at pH 7, 20 degrees C, compared to 8.5 mmHg and n approximately 2.8 for native HbA under identical, dilute conditions.
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Affiliation(s)
- Anna L Asmundson
- Department of Chemistry, Western Washington University, Bellingham, Washington 98225-9150, USA
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Domingues E, Brillet T, Vasseur C, Agier V, Marden MC, Baudin-Creuza V. Construction of a new polycistronic vector for over-expression and rapid purification of human hemoglobin. Plasmid 2009; 61:71-7. [DOI: 10.1016/j.plasmid.2008.09.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2008] [Revised: 09/16/2008] [Accepted: 09/24/2008] [Indexed: 11/30/2022]
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