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Demir Özer E, Yildirim M. The modification of nisin with homocysteine thiolactone and its effect on antimicrobial activity. Braz J Microbiol 2024; 55:191-199. [PMID: 38082122 PMCID: PMC10920495 DOI: 10.1007/s42770-023-01207-8] [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: 09/14/2023] [Accepted: 12/02/2023] [Indexed: 03/09/2024] Open
Abstract
The aim of the present study is to make an important contribution to the literature by focusing on the preparation of the N-homocysteine conjugate of nisin and evaluating the effect of the N-homocysteinylation reaction on its antimicriobial activity. The modification process was monitored using both acetic acid urea polyacrylamide gel electrophoresis (AAU-PAGE) and tricine sodium dodecyl sulphate polyacrylamide gel electrophoresis (tricine SDS-PAGE). The antibacterial effectiveness of modified nisin was assessed against Staphylococcus aureus ATCC 6538, Enterococcus faecium ATCC 9097, Bacillus subtilis ATCC 6633, Lactococcus lactis ssp. cremoris AÜ, Listeria monocytogenes NCTC 5348, and Escherichia coli RSKK. Optimal conditions for achieving the highest N-homocysteinylation degree (6.30%) were determined as 6 mg/mL nisin, 150 mM homocysteine thiolactone, 150 rpm shaking rate, pH of 3.0, and a reaction time of 6 h. The modified nisin obtained did not have a significant inhibitory effect on the strains tested except E. faecium. E. faecium was inhibited by the modified nisin and its antibacterial activity was determined as approximately 10% of the antibacterial activity of unmodified nisin. On the other hand, hydrolysis of nisin by trypsin and thermolysin resulted in significant specific side chain modifications induced by the homocysteine-thiolactone reaction, especially at Lys12 and Lys22. The results provide valuable insights into the potential of N-homocysteinylation to improve the antibacterial properties of nisin and also suggest that the effects of specific modifications identified during the modification process should be investigated.
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Affiliation(s)
- Ezgi Demir Özer
- Department of Gastronomy and Culinary Arts, Cappadocia University, Nevşehir, Turkey.
| | - Metin Yildirim
- Department of Food Engineering, Niğde Ömer Halisdemir University, Niğde, Turkey
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2
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Kumari K, Sharma GS, Gupta A, Singh KS, Singh LR. Functionally active cross-linked protein oligomers formed by homocysteine thiolactone. Sci Rep 2023; 13:5620. [PMID: 37024663 PMCID: PMC10079695 DOI: 10.1038/s41598-023-32694-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 03/31/2023] [Indexed: 04/08/2023] Open
Abstract
Deposition of high-order protein oligomers is a common hallmark of a large number of human diseases and therefore, has been of immense medical interest. From the past several decades, efforts are being made to characterize protein oligomers and explore how they are linked with the disease pathologies. In general, oligomers are non-functional, rather cytotoxic in nature while the functional (non-cytotoxic) oligomers are quite rare. In the present study, we identified new protein oligomers of Ribonuclease-A and Lysozyme that contain functionally active fractions. These functional oligomers are disulfide cross-linked, native-like, and obtained as a result of the covalent modification of the proteins by the toxic metabolite, homocysteine thiolactone accumulated under hyperhomocysteinemia (a condition responsible for cardiovascular complications including atherosclerosis). These results have been obtained from the extensive analysis of the nature of oligomers, functional status, and structural integrity of the proteins using orthogonal techniques. The study implicates the existence of such oligomers as protein sinks that may sequester toxic homocysteines in humans.
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Affiliation(s)
- Kritika Kumari
- Dr. B. R. Ambedkar Center for Biomedical Research, University of Delhi, Delhi, 110007, India
| | - Gurumayum Suraj Sharma
- Department of Botany, Bhaskaracharya College of Applied Sciences, University of Delhi, New Delhi, 110075, India
| | - Akshita Gupta
- Dr. B. R. Ambedkar Center for Biomedical Research, University of Delhi, Delhi, 110007, India
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3
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Bag S, Konar M, Roy P, DasGupta S, Dasgupta S. Homocysteine thiolactone and H 2 O 2 induce amino acid modifications and alter the fibrillation propensity of the Aβ 25-35 peptide. FEBS Lett 2023; 597:1041-1051. [PMID: 36694268 DOI: 10.1002/1873-3468.14583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Revised: 11/16/2022] [Accepted: 01/06/2023] [Indexed: 01/26/2023]
Abstract
Of the proteinaceous β-sheet-rich amyloid fibrillar structures, the Aβ25-35 peptide, a component of the full-length Aβ involved in Alzheimer's disease, has similar toxicity to the parent peptide. In this study, the effects of homocysteine thiolactone (HCTL) and hydrogen peroxide (H2 O2 ) on the conformation and fibrillation propensity of the Aβ25-35 peptide were investigated. Both HCTL and H2 O2 induced amino acid modifications along with alteration in aggregation propensity. Methionine (Met)-35 was oxidized by H2 O2 and aggregation was attenuated following the increased hydrophilicity of the peptide due to sulfoxide/sulfone formation. The HCTL-modified lysine (Lys-28) residue destabilizes the structure of the peptide, which leads to fibrillation. Our studies provide important information regarding the relationship between amino acid modifications and the amyloid fibrillation process.
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Affiliation(s)
- Sudipta Bag
- Department of Chemistry, Indian Institute of Technology Kharagpur, India.,Sister Nivedita University, New Town, India
| | - Mouli Konar
- Department of Chemistry, Indian Institute of Technology Kharagpur, India
| | - Pritam Roy
- Department of Chemistry, Indian Institute of Technology Kharagpur, India
| | - Sunando DasGupta
- Department of Chemical Engineering, Indian Institute of Technology Kharagpur, India
| | - Swagata Dasgupta
- Department of Chemistry, Indian Institute of Technology Kharagpur, India
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4
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Reddy VS, Trinath J, Reddy GB. Implication of homocysteine in protein quality control processes. Biochimie 2019; 165:19-31. [PMID: 31269461 DOI: 10.1016/j.biochi.2019.06.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Accepted: 06/26/2019] [Indexed: 12/22/2022]
Abstract
Homocysteine (Hcy) is a key metabolite generated during methionine metabolism. The elevated levels of Hcy in the blood are reffered to as hyperhomocystenimeia (HHcy). The HHcy is caused by impaired metabolism/deficiency of either folate or B12 or defects in Hcy metabolism. Accumulating evidence suggests that HHcy is associated with cardiovascular and brain diseases including atherosclerosis, endothelial injury, and stroke etc. Vitamin B12 (cobalamin; B12) is a water-soluble vitamin essential for two metabolic reactions. It acts as a co-factor for methionine synthase and L-methylmalonyl-CoA mutase. Besides, it is also vital for DNA synthesis and maturation of RBC. Deficiency of B12 is associated with haematological and neurological disorders. Hyperhomocysteinemia (HHcy)-induced toxicity is thought to be mediated by the accumulation of Hcy and its metabolites, homocysteinylated proteins. Cellular protein quality control (PQC) is essential for the maintenance of proteome integrity, and cell viability and its failure contributes to the development of multiple diseases. Chaperones, unfolded protein response (UPR), ubiquitin-proteasome system (UPS), and autophagy are analogous strategies of PQC that maintain cellular proteome integrity. Recently, multiple studies reported that HHcy responsible for perturbation of PQC by reducing chaperone levels, activating UPR, and impairing autophagy. Besides, HHcy also induce cytotoxicity, inflammation, protein aggregation and apoptosis. It has been shown that some of the factors including altered SIRT1-HSF1 axis and irreversible homocysteinylation of proteins are responsible for folate and/or B12 deficiency or HHcy-induced impairment of PQC. Therefore, this review highlights the current understanding of HHcy in the context of cellular PQC and their pathophysiological and clinical consequences, epigenomic changes, therapeutic implications of B12, and chemical chaperones based on cell culture and experimental animal models.
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Affiliation(s)
- V Sudhakar Reddy
- Biochemistry Division, National Institute of Nutrition, Hyderabad, India.
| | - Jamma Trinath
- Department of Biological Sciences, BITS-Pilani, 500078, Hyderabad Campus, Hyderabad, Telangana, India
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5
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Jakubowski H. Homocysteine Modification in Protein Structure/Function and Human Disease. Physiol Rev 2019; 99:555-604. [PMID: 30427275 DOI: 10.1152/physrev.00003.2018] [Citation(s) in RCA: 152] [Impact Index Per Article: 30.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Epidemiological studies established that elevated homocysteine, an important intermediate in folate, vitamin B12, and one carbon metabolism, is associated with poor health, including heart and brain diseases. Earlier studies show that patients with severe hyperhomocysteinemia, first identified in the 1960s, exhibit neurological and cardiovascular abnormalities and premature death due to vascular complications. Although homocysteine is considered to be a nonprotein amino acid, studies over the past 2 decades have led to discoveries of protein-related homocysteine metabolism and mechanisms by which homocysteine can become a component of proteins. Homocysteine-containing proteins lose their biological function and acquire cytotoxic, proinflammatory, proatherothrombotic, and proneuropathic properties, which can account for the various disease phenotypes associated with hyperhomocysteinemia. This review describes mechanisms by which hyperhomocysteinemia affects cellular proteostasis, provides a comprehensive account of the biological chemistry of homocysteine-containing proteins, and discusses pathophysiological consequences and clinical implications of their formation.
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Affiliation(s)
- Hieronim Jakubowski
- Department of Microbiology, Biochemistry and Molecular Genetics, Rutgers-New Jersey Medical School, International Center for Public Health , Newark, New Jersey ; and Department of Biochemistry and Biotechnology, Poznań University of Life Sciences , Poznań , Poland
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6
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Schiappacasse A, Maltaneri RE, Chamorro ME, Nesse AB, Wetzler DE, Vittori DC. Modification of erythropoietin structure by N-homocysteinylation affects its antiapoptotic and proliferative functions. FEBS J 2018; 285:3801-3814. [PMID: 30103295 DOI: 10.1111/febs.14632] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Revised: 06/26/2018] [Accepted: 08/10/2018] [Indexed: 12/19/2022]
Abstract
Many patients under therapy with recombinant human erythropoietin (rhuEPO) show resistance to the treatment, an effect likely associated with the accumulation of tissue factors, especially in renal and cardiovascular diseases. Hyperhomocysteinemia due to high serum levels of homocysteine has been suggested among the risk factors in those pathologies. Its main effect is the N-homocysteinylation of proteins due to the interaction between the highly reactive homocysteine thiolactone (HTL) and lysine residues. The aim of this study was to evaluate the effect of N-homocysteinylation on the erythropoietic and antiapoptotic abilities of EPO, which can be a consequence of structural changes in the modified protein. We found that both cellular functions were altered in the presence of HTL-EPO. A decreased net positive charge of HTL-EPO was detected by capillary zone electrophoresis, while analysis of polyacrylamide gel electropherograms suggested formation of aggregates. Far-UV spectra, obtained by Circular Dichroism Spectroscopy, indicated a switch of the protein's secondary structure from α-helix to β-sheet structures. Results of Congo red and Thioflavin T assays confirm the formation of repetitive β-sheet structures, which may account for aggregates. Accordingly, Dynamic Light Scattering analysis showed a markedly larger radius of the HTL-EPO structures, supporting the formation of soluble oligomers. These structural changes might interfere with the conformational adaptations necessary for efficient ligand-receptor interaction, thus affecting the proliferative and antiapoptotic functions of EPO. The present findings may contribute to explain the resistance exhibited by patients with cardio-renal syndrome to treatment with rhuEPO, as a consequence of structural modifications due to protein N-homocysteinylation.
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Affiliation(s)
- Agustina Schiappacasse
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Instituto del Departamento de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN), Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | - Romina Eugenia Maltaneri
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Instituto del Departamento de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN), Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | - María Eugenia Chamorro
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Instituto del Departamento de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN), Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | - Alcira Beatriz Nesse
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Instituto del Departamento de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN), Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | - Diana Elena Wetzler
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Instituto del Departamento de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN), Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | - Daniela Cecilia Vittori
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Instituto del Departamento de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN), Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
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7
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Akbarian M, Ghasemi Y, Uversky VN, Yousefi R. Chemical modifications of insulin: Finding a compromise between stability and pharmaceutical performance. Int J Pharm 2018; 547:450-468. [DOI: 10.1016/j.ijpharm.2018.06.023] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Revised: 06/06/2018] [Accepted: 06/07/2018] [Indexed: 02/07/2023]
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8
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Xu W, Tian M, Zhou Y. The relationship between insulin resistance, adiponectin and C-reactive protein and vascular endothelial injury in diabetic patients with coronary heart disease. Exp Ther Med 2018; 16:2022-2026. [PMID: 30186434 PMCID: PMC6122372 DOI: 10.3892/etm.2018.6407] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 06/27/2018] [Indexed: 12/14/2022] Open
Abstract
Relationship between insulin resistance, adiponectin and C-reactive protein and vascular endothelial injury in diabetic patients with coronary heart disease (CHD) was investigated. Clinical data of 72 patients with diabetes mellitus diagnosed in Weifang People's Hospital (Weifang, China) from October 2015 to January 2017 were retrospectively analyzed. Thirty patients were combined with CHD and 42 patients were not. There were 43 males and 29 females. General information and clinical data including age, sex, duration of diabetes mellitus, biochemical indicators, fasting insulin levels, CRP, insulin resistance index, arterial lesions of coronary angiography and Gensini scores were collected. The levels of FINS, FPG, HOMA-R and CPR were significantly higher, and the level of ADPN was significantly lower in diabetes complicated with CHD group than that without CHD group (P<0.05). Incidence of single coronary artery disease and mild coronary lesion were significantly lower, and incidences of double and triple lesions were significantly higher in diabetes complicated with CHD group than that without CHD group (P<0.05). Gensini score was significantly higher in diabetes complicated with CHD group than that without CHD group (P<0.05); Analysis of the correlation showed that CRP (r=0.422, P=0.001) and insulin resistance index (r=0.828, P=0.001) were positively correlated with Gensini score, while the adiponectin level was negatively correlated with Gensini score (r= −0.719, P<0.001). Logistic regression analysis showed that FINS, ADPN, HOMA-R, CPR, duration of diabetes mellitus and BMI had independently predictive value for diabetes complicated with CHD (P<0.05). Serum adiponectin, insulin resistance and CPR levels are closely related to diabetes mellitus combined with coronary heart disease, and can affect the degree of vascular endothelial injury in coronary heart disease.
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Affiliation(s)
- Weihua Xu
- Department of Emergency, Weifang People's Hospital, Weifang, Shandong 261041, P.R. China
| | - Minghui Tian
- Department of Emergency, Weifang People's Hospital, Weifang, Shandong 261041, P.R. China
| | - Yanju Zhou
- Department of Emergency, Weifang People's Hospital, Weifang, Shandong 261041, P.R. China
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9
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Guo T, Jiang Q, Yu Z. Copper-Catalyzed Ring-Expansion/ThiolactonizationviaAzidation of Internal Olefinic C-H Bond under Mild Conditions. Adv Synth Catal 2016. [DOI: 10.1002/adsc.201600675] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Tenglong Guo
- Dalian Institute of Chemical Physics; Chinese Academy of Sciences; 457 Zhongshan Road Dalian, Liaoning 116023 People's Republic of China
| | - Quanbin Jiang
- Dalian Institute of Chemical Physics; Chinese Academy of Sciences; 457 Zhongshan Road Dalian, Liaoning 116023 People's Republic of China
| | - Zhengkun Yu
- Dalian Institute of Chemical Physics; Chinese Academy of Sciences; 457 Zhongshan Road Dalian, Liaoning 116023 People's Republic of China
- State Key Laboratory of Organometallic Chemistry; Shanghai Institute of Organic Chemistry; Chinese Academy of Sciences; 354 Fenglin Road Shanghai 200032 People's Republic of China
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10
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Homocystinuria: Therapeutic approach. Clin Chim Acta 2016; 458:55-62. [PMID: 27059523 DOI: 10.1016/j.cca.2016.04.002] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Revised: 04/02/2016] [Accepted: 04/03/2016] [Indexed: 11/22/2022]
Abstract
Homocystinuria is a disorder of sulfur metabolism pathway caused by deficiency of cystathionine β-synthase (CBS). It is characterized by increased accumulation of homocysteine (Hcy) in the cells and plasma. Increased homocysteine results in various vascular and neurological complications. Present strategies to lower cellular and plasma homocysteine levels include vitamin B6 intake, dietary methionine restriction, betaine supplementation, folate and vitamin B12 administration. However, these strategies are inefficient for treatment of homocystinuria. In recent years, advances have been made towards developing new strategies to treat homocystinuria. These mainly include functional restoration to mutant CBS, enhanced clearance of Hcy from the body, prevention of N-homocysteinylation-induced toxicity and inhibition of homocysteine-induced oxidative stress. In this review, we have exclusively discussed the recent advances that have been achieved towards the treatment of homocystinuria. The review is an attempt to help clinicians in developing effective therapeutic strategies and designing novel drugs against homocystinuria.
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11
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Protein N-homocysteinylation: From cellular toxicity to neurodegeneration. Biochim Biophys Acta Gen Subj 2015; 1850:2239-45. [DOI: 10.1016/j.bbagen.2015.08.013] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 08/18/2015] [Accepted: 08/24/2015] [Indexed: 12/29/2022]
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12
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Desmet GB, D’hooge DR, Sabbe MK, Marin GB, Du Prez FE, Espeel P, Reyniers MF. Computational Study and Kinetic Analysis of the Aminolysis of Thiolactones. J Org Chem 2015; 80:8520-9. [DOI: 10.1021/acs.joc.5b01446] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Gilles B. Desmet
- Laboratory
for Chemical Technology, Ghent University, Technologiepark 914, B-9052 Gent, Belgium
| | - Dagmar R. D’hooge
- Laboratory
for Chemical Technology, Ghent University, Technologiepark 914, B-9052 Gent, Belgium
| | - Maarten K. Sabbe
- Laboratory
for Chemical Technology, Ghent University, Technologiepark 914, B-9052 Gent, Belgium
| | - Guy B. Marin
- Laboratory
for Chemical Technology, Ghent University, Technologiepark 914, B-9052 Gent, Belgium
| | - Filip E. Du Prez
- Polymer
Chemistry Research Group, Ghent University, Krijgslaan 281 S4-bis, B-9000 Gent, Belgium
| | - Pieter Espeel
- Polymer
Chemistry Research Group, Ghent University, Krijgslaan 281 S4-bis, B-9000 Gent, Belgium
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13
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Yousefi R, Taheri B, Alavi P, Shahsavani MB, Asadi Z, Ghahramani M, Niazi A, Alavianmehr MM, Moosavi-Movahedi AA. Aspirin-mediated acetylation induces structural alteration and aggregation of bovine pancreatic insulin. J Biomol Struct Dyn 2015; 34:362-75. [DOI: 10.1080/07391102.2015.1039584] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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14
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Sharma GS, Kumar T, Singh LR. N-homocysteinylation induces different structural and functional consequences on acidic and basic proteins. PLoS One 2014; 9:e116386. [PMID: 25551634 PMCID: PMC4281231 DOI: 10.1371/journal.pone.0116386] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Accepted: 12/06/2014] [Indexed: 12/23/2022] Open
Abstract
One of the proposed mechanisms of homocysteine toxicity in human is the modification of proteins by the metabolite of Hcy, homocysteine thilolactone (HTL). Incubation of proteins with HTL has earlier been shown to form covalent adducts with ε-amino group of lysine residues of protein (called N-homocysteinylation). It has been believed that protein N-homocysteinylation is the pathological hallmark of cardiovascular and neurodegenerative disorders as homocysteinylation induces structural and functional alterations in proteins. In the present study, reactivity of HTL towards proteins with different physico-chemical properties and hence their structural and functional alterations were studied using different spectroscopic approaches. We found that N-homocysteinylation has opposite consequences on acidic and basic proteins suggesting that pI of the protein determines the extent of homocysteinylation, and the structural and functional consequences due to homocysteinylation. Mechanistically, pI of protein determines the extent of N-homocysteinylation and the associated structural and functional alterations. The study suggests the role of HTL primarily targeting acidic proteins in eliciting its toxicity that could yield mechanistic insights for the associated neurodegeneration.
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Affiliation(s)
| | - Tarun Kumar
- Dr. B. R. Ambedkar Center for Biomedical Research, University of Delhi, Delhi, India
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15
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Kumar T, Sharma GS, Singh LR. Existence of molten globule state in homocysteine-induced protein covalent modifications. PLoS One 2014; 9:e113566. [PMID: 25405350 PMCID: PMC4236184 DOI: 10.1371/journal.pone.0113566] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Accepted: 10/29/2014] [Indexed: 12/03/2022] Open
Abstract
Homocysteine thiolactone is a toxic metabolite produced from homocysteine by amino-acyl t-RNA synthetase in error editing reaction. The basic cause of toxicity of homocysteine thiolactone is believed to be due to the adduct formation with lysine residues (known as protein N-homocysteinylation) leading to protein aggregation and loss of enzyme function. There was no data available until now that showed the effect of homocysteine thiolactone on the native state structural changes that led to aggregate formation. In the present study we have investigated the time dependent structural changes due to homocysteine thiolactone induced modifications on three different proteins having different physico-chemical properties (cytochrome-c, lysozyme and alpha lactalbumin). We discovered that N-homocysteinylation leads to the formation of molten globule state—an important protein folding intermediate in the protein folding pathway. We also found that the formation of the molten globule state might be responsible for the appearance of aggregate formation. The study indicates the importance of protein folding intermediate state in eliciting the homocysteine thiolactone toxicity.
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Affiliation(s)
- Tarun Kumar
- Dr. B. R. Ambedkar Center for Biomedical Research, University of Delhi, Delhi, India
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16
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Genoud V, Castañon M, Lauricella AM, Quintana I. Characterization of N-homocysteinylated Albumin Adducts. Protein J 2014; 33:85-91. [DOI: 10.1007/s10930-013-9540-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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17
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Structural analysis and aggregation propensity of reduced and nonreduced glycated insulin adducts. Appl Biochem Biotechnol 2013; 170:623-38. [PMID: 23584594 DOI: 10.1007/s12010-013-0207-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2012] [Accepted: 03/18/2013] [Indexed: 12/24/2022]
Abstract
The milieu within pancreatic β cells represents a favorable environment for glycation of insulin. Therefore, in this study, insulin samples were individually subjected to glycation under reducing and nonreducing conditions. As monitored by ortho-phthalaldehyde and fluorescamine assays, the reduced glycated insulin adduct demonstrates extensively higher level of glycation than the nonreduced glycated counterpart. Also, gel electrophoresis experiments suggest a significant impact of glycation under a reducing system on the level of insulin oligomerization. Furthermore, reduced and nonreduced glycated insulin adducts respectively exhibit full and partial resistance against dithiothreitol-induced aggregation. The results of thioflavin T and Congo red assays suggest the existence of a significant quantity of amyloid-like entities in the sample of reduced glycated insulin adduct. Both fluorescence and far-ultraviolet circular dichroism studies respectively suggest that the extents of unfolding and secondary structural alteration were closely correlated to the level of insulin glycation. Moreover, the surface tension of two glycated insulin adducts was inversely correlated to their glycation extents and to the quantity of exposed hydrophobic patches. Overall, the glucose-modified insulin molecules under reducing and nonreducing systems display different structural features having significant consequences on aggregation behaviors and surface tension properties. The particular structural constraints of glycated insulin may reduce the binding interaction of this hormone to its receptor which is important for both insulin function and clearance.
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18
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Yousefi R, Jalili S, Alavi P, Moosavi-Movahedi AA. The enhancing effect of homocysteine thiolactone on insulin fibrillation and cytotoxicity of insulin fibril. Int J Biol Macromol 2012; 51:291-8. [DOI: 10.1016/j.ijbiomac.2012.05.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2012] [Revised: 05/14/2012] [Accepted: 05/15/2012] [Indexed: 10/28/2022]
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19
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Formation of supramolecular structures of a native-like protein in the presence of amphiphilic peptides: Variations in aggregate morphology. FEBS Lett 2011; 586:186-90. [DOI: 10.1016/j.febslet.2011.12.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2011] [Revised: 11/20/2011] [Accepted: 12/14/2011] [Indexed: 11/21/2022]
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Yousefi R, Jalili S. The synergistic chaperoning operation in a Bi-chaperone system consisting of alpha-crystallin and beta-casein: Bovine pancreatic insulin as the target protein. Colloids Surf B Biointerfaces 2011; 88:497-504. [DOI: 10.1016/j.colsurfb.2011.07.040] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2011] [Revised: 07/08/2011] [Accepted: 07/15/2011] [Indexed: 10/18/2022]
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