1
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Alavi Z, Casanova-Morales N, Quiroga-Roger D, Wilson CAM. Towards the understanding of molecular motors and its relationship with local unfolding. Q Rev Biophys 2024; 57:e7. [PMID: 38715547 DOI: 10.1017/s0033583524000052] [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] [Indexed: 06/14/2024]
Abstract
Molecular motors are machines essential for life since they convert chemical energy into mechanical work. However, the precise mechanism by which nucleotide binding, catalysis, or release of products is coupled to the work performed by the molecular motor is still not entirely clear. This is due, in part, to a lack of understanding of the role of force in the mechanical-structural processes involved in enzyme catalysis. From a mechanical perspective, one promising hypothesis is the Haldane-Pauling hypothesis which considers the idea that part of the enzymatic catalysis is strain-induced. It suggests that enzymes cannot be efficient catalysts if they are fully complementary to the substrates. Instead, they must exert strain on the substrate upon binding, using enzyme-substrate energy interaction (binding energy) to accelerate the reaction rate. A novel idea suggests that during catalysis, significant strain energy is built up, which is then released by a local unfolding/refolding event known as 'cracking'. Recent evidence has also shown that in catalytic reactions involving conformational changes, part of the heat released results in a center-of-mass acceleration of the enzyme, raising the possibility that the heat released by the reaction itself could affect the enzyme's integrity. Thus, it has been suggested that this released heat could promote or be linked to the cracking seen in proteins such as adenylate kinase (AK). We propose that the energy released as a consequence of ligand binding/catalysis is associated with the local unfolding/refolding events (cracking), and that this energy is capable of driving the mechanical work.
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Affiliation(s)
- Zahra Alavi
- Department of Physics, Loyola Marymount University, Los Angeles, CA, USA
| | | | - Diego Quiroga-Roger
- Biochemistry and Molecular Biology Department, Faculty of Chemistry and Pharmaceutical Sciences, Universidad de Chile, Santiago, Chile
| | - Christian A M Wilson
- Biochemistry and Molecular Biology Department, Faculty of Chemistry and Pharmaceutical Sciences, Universidad de Chile, Santiago, Chile
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2
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Panda K, Sahoo I, Bisoi SK, Dash M. Severe Hemolytic Anemia due to Erythrocyte Adenylate Kinase Deficiency due to a Novel Missense Mutation (c.518T>G). Indian J Pediatr 2024; 91:206. [PMID: 37782390 DOI: 10.1007/s12098-023-04870-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Accepted: 09/11/2023] [Indexed: 10/03/2023]
Affiliation(s)
- Kalpana Panda
- Department of Pediatrics, Institute of Medical Sciences & SUM Hospital, Bhubaneswar, Odisha, India
| | - Ipsita Sahoo
- Department of Pediatrics, Institute of Medical Sciences & SUM Hospital, Bhubaneswar, Odisha, India
| | - Swarup Kumar Bisoi
- Department of Pediatrics, Institute of Medical Sciences & SUM Hospital, Bhubaneswar, Odisha, India
| | - Mrutunjay Dash
- Department of Pediatrics, Institute of Medical Sciences & SUM Hospital, Bhubaneswar, Odisha, India.
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3
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He S, Chen H, Guo X, Gao J. Red cell adenylate kinase deficiency in China: molecular study of 2 new mutations (413G > A, 223dupA). BMC Med Genomics 2022; 15:102. [PMID: 35509045 PMCID: PMC9066714 DOI: 10.1186/s12920-022-01248-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Accepted: 04/22/2022] [Indexed: 11/14/2022] Open
Abstract
Background Adenylate kinase (AK) is a monomolecular enzyme widely found in a variety of organisms. It mainly catalyses the reversible transfer of adenosine nucleotide phosphate groups and plays an important role in maintaining energy metabolism. AK deficiency is a rare genetic disorder that is related to haemolytic anaemia. Chronic haemolytic anaemia associated with AK deficiency is a rare condition, and only 14 unrelated families have been reported thus far. Moreover, only 11 mutations have been identified in the AK1 gene, with only 3 cases of psychomotor impairment. Case presentation The patient was a 3-year-old boy with severe haemolytic anaemia and psychomotor retardation. A molecular study of the patient’s AK gene revealed 2 different mutations: a heterozygous missense mutation in exon 6 (c.413G > A) and a heterozygous frameshift mutation in exon 5 (c.223dupA). Molecular modelling analyses indicated that AK gene inactivation resulted in a lack of AK activity. The patient recovered after regular blood transfusion therapy. Conclusions AK1 deficiency was diagnosed on the basis of low enzymatic activity and the identification of a mutation in the AK1 gene located on chromosome 9q. Here, we report the first case of moderate red cell AK1 deficiency associated with chronic nonspherocytic haemolytic anaemia (CNSHA) in China. The genetic mutations were confirmed by Sanger sequencing. The variants were classified as pathogenic by bioinformatics tools, such as ACMG/AMP guidelines, Mutation Taster, SIFT, MACP, REVEL and PolyPhen2.2. Based on our evidence and previous literature reports, we speculate that the site of the AK1 gene c.413G > A (p.Arg138His) mutation may be a high-frequency mutation site and the other mutation (c.223dupA) might be related to the neuropathogenicity caused by AK1 deficiency. NGS should be a part of newborn to early childhood screening to diagnose rare and poorly diagnosed genetic diseases as early as possible. Supplementary Information The online version contains supplementary material available at 10.1186/s12920-022-01248-2.
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Affiliation(s)
- Sijia He
- Department of Peadiatrics, West China Second University Hospital, Sichuan University, Chengdu, 610041, China.,Key Laboratory of Birth Defects and Related Diseases of Women and Children, Sichuan University, Ministry of Education, Chengdu, 610041, China
| | - Hongbo Chen
- Department of Peadiatrics, West China Second University Hospital, Sichuan University, Chengdu, 610041, China
| | - Xia Guo
- Department of Peadiatrics, West China Second University Hospital, Sichuan University, Chengdu, 610041, China. .,Key Laboratory of Birth Defects and Related Diseases of Women and Children, Sichuan University, Ministry of Education, Chengdu, 610041, China.
| | - Ju Gao
- Department of Peadiatrics, West China Second University Hospital, Sichuan University, Chengdu, 610041, China. .,Key Laboratory of Birth Defects and Related Diseases of Women and Children, Sichuan University, Ministry of Education, Chengdu, 610041, China.
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4
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Sivasankaran M, Reddy VK, Kumar V, Munirathnam D. Hereditary Non-Spherocytic Hemolytic Anemia (HNSHA): Four Children with Rare Hereditary Red Cell Enzymopathies. Indian Pediatr 2021. [PMID: 34636333 PMCID: PMC8549597 DOI: 10.1007/s13312-021-2339-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Meena Sivasankaran
- Department of Pediatric Haemato-Oncology and Bone Marrow Transplantation, Kanchi Kamakoti CHILD Trust Hopsital, Numgambakkam, Chennai, Tamil Nadu.
| | - Vamsi Krishna Reddy
- Department of Pediatrics, Kanchi Kamakoti CHILD Trust Hopsital, Numgambakkam, Chennai, Tamil Nadu
| | - Vimal Kumar
- Department of Pediatric Haemato-Oncology and Bone Marrow Transplantation, Kanchi Kamakoti CHILD Trust Hopsital, Numgambakkam, Chennai, Tamil Nadu
| | - Deenadayalan Munirathnam
- Department of Pediatric Haemato-Oncology and Bone Marrow Transplantation, Kanchi Kamakoti CHILD Trust Hopsital, Numgambakkam, Chennai, Tamil Nadu
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5
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Wujak M, Kozakiewicz A, Ciarkowska A, Loch JI, Barwiolek M, Sokolowska Z, Budny M, Wojtczak A. Assessing the Interactions of Statins with Human Adenylate Kinase Isoenzyme 1: Fluorescence and Enzyme Kinetic Studies. Int J Mol Sci 2021; 22:ijms22115541. [PMID: 34073952 PMCID: PMC8197361 DOI: 10.3390/ijms22115541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Revised: 05/16/2021] [Accepted: 05/21/2021] [Indexed: 11/16/2022] Open
Abstract
Statins are the most effective cholesterol-lowering drugs. They also exert many pleiotropic effects, including anti-cancer and cardio- and neuro-protective. Numerous nano-sized drug delivery systems were developed to enhance the therapeutic potential of statins. Studies on possible interactions between statins and human proteins could provide a deeper insight into the pleiotropic and adverse effects of these drugs. Adenylate kinase (AK) was found to regulate HDL endocytosis, cellular metabolism, cardiovascular function and neurodegeneration. In this work, we investigated interactions between human adenylate kinase isoenzyme 1 (hAK1) and atorvastatin (AVS), fluvastatin (FVS), pravastatin (PVS), rosuvastatin (RVS) and simvastatin (SVS) with fluorescence spectroscopy. The tested statins quenched the intrinsic fluorescence of hAK1 by creating stable hAK1-statin complexes with the binding constants of the order of 104 M−1. The enzyme kinetic studies revealed that statins inhibited hAK1 with significantly different efficiencies, in a noncompetitive manner. Simvastatin inhibited hAK1 with the highest yield comparable to that reported for diadenosine pentaphosphate, the only known hAK1 inhibitor. The determined AK sensitivity to statins differed markedly between short and long type AKs, suggesting an essential role of the LID domain in the AK inhibition. Our studies might open new horizons for the development of new modulators of short type AKs.
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Affiliation(s)
- Magdalena Wujak
- Faculty of Pharmacy, Nicolaus Copernicus University in Toruń, Collegium Medicum in Bydgoszcz, Jurasza 2, 85-089 Bydgoszcz, Poland;
- Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University in Toruń, Lwowska 1, 87-100 Toruń, Poland;
| | - Anna Kozakiewicz
- Faculty of Chemistry, Nicolaus Copernicus University in Toruń, Gagarina 7, 87-100 Toruń, Poland; (M.B.); (Z.S.); (A.W.)
- Correspondence: ; Tel.: +48-56-611-4511
| | - Anna Ciarkowska
- Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University in Toruń, Lwowska 1, 87-100 Toruń, Poland;
| | - Joanna I. Loch
- Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Kraków, Poland;
| | - Magdalena Barwiolek
- Faculty of Chemistry, Nicolaus Copernicus University in Toruń, Gagarina 7, 87-100 Toruń, Poland; (M.B.); (Z.S.); (A.W.)
| | - Zuzanna Sokolowska
- Faculty of Chemistry, Nicolaus Copernicus University in Toruń, Gagarina 7, 87-100 Toruń, Poland; (M.B.); (Z.S.); (A.W.)
| | - Marcin Budny
- Synthex Technologies Sp. z o.o., Gagarina 7/134B, 87-100 Toruń, Poland;
| | - Andrzej Wojtczak
- Faculty of Chemistry, Nicolaus Copernicus University in Toruń, Gagarina 7, 87-100 Toruń, Poland; (M.B.); (Z.S.); (A.W.)
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6
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Dudzinska W, Lubkowska A. Changes in the Concentration of Purine and Pyridine as a Response to Single Whole-Body Cryostimulation. Front Physiol 2021; 12:634816. [PMID: 33584352 PMCID: PMC7873528 DOI: 10.3389/fphys.2021.634816] [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: 11/28/2020] [Accepted: 01/08/2021] [Indexed: 11/29/2022] Open
Abstract
To our knowledge, this is the first study in which we provide evidence that a single whole-body cryostimulation treatment leads to changes associated with erythrocyte energy metabolism. These changes are beneficial from the point of view of cellular bioenergetics, because they are associated with an increase in ATP concentration and erythrocyte energy potential expressed by an increase in the ATP/ADP and ATP/AMP ratios and the value of adenylate energy charge (AEC). In addition, as affected by cryogenic temperatures, there is a decrease in the concentration of purine catabolism products, i.e., inosine and hypoxanthine in the blood.
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Affiliation(s)
- Wioleta Dudzinska
- Institute of Biology, University of Szczecin, Szczecin, Poland.,Department of Functional Diagnostics and Physical Medicine, Pomeranian Medical University in Szczecin, Szczecin, Poland
| | - Anna Lubkowska
- Department of Functional Diagnostics and Physical Medicine, Pomeranian Medical University in Szczecin, Szczecin, Poland
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7
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Zaninoni A, Fermo E, Vercellati C, Marcello AP, Barcellini W, Bianchi P. Congenital Hemolytic Anemias: Is There a Role for the Immune System? Front Immunol 2020; 11:1309. [PMID: 32655575 PMCID: PMC7324678 DOI: 10.3389/fimmu.2020.01309] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 05/22/2020] [Indexed: 01/19/2023] Open
Abstract
Congenital hemolytic anemias (CHAs) are a heterogeneous group of rare hereditary conditions including defects of erythrocyte membrane proteins, red cell enzymes, and disorders due to defective erythropoiesis. They are characterized by variable degree of anemia, chronic extravascular hemolysis, reduced erythrocyte life span, splenomegaly, jaundice, biliary lithiasis, and iron overload. Although few data are reported on the role of the immune system in CHAs, several immune-mediated mechanisms may be involved in the pathogenesis of these rare diseases. We reported in ~60% of patients with hereditary spherocytosis (HS), the presence of naturally-occurring autoantibodies (NAbs) directed against different membrane proteins (α- and β-spectrin, band 3, and dematin). Positive HS subjects showed a more hemolytic pattern and NAbs were more evident in aged erythrocytes. The latter is in line with the function of NAbs in the opsonization of damaged/senescent erythrocytes and their consequent removal in the spleen. Splenectomy, usually performed to reduce erythrocyte catheresis and improve Hb levels, has different efficacy in various CHAs. Median Hb increase is 3 g/dL in HS, 1.6–1.8 g/dL in pyruvate kinase deficiency (PKD), and 1 g/dL in congenital dyserythropoietic anemias (CDA) type II. Consistently with clinical severity, splenectomy is performed in 20% of HS, 45% of CDAII, and in 60% of PKD patients. Importantly, sepsis and thrombotic events have been registered, particularly in PKD with a frequency of ~7% for both. Furthermore, we analyzed the role of pro-inflammatory cytokines and found that interleukin 10 and interferon γ, and to a lesser extent interleukin 6, were increased in all CHAs compared with controls. Moreover, CDAII and enzymatic defects showed increased tumor necrosis factor-α and reduced interleukin 17. Finally, we reported that iron overload occurred in 31% of patients with membrane defects, in ~60% of CDAII cases, and in up to 82% of PKD patients (defined by MRI liver iron concentration >4 mg Fe/gdw). Hepcidin was slightly increased in CHAs compared with controls and positively correlated with ferritin and with the inflammatory cytokines interleukin 6 and interferon γ. Overall the results suggest the existence of a vicious circle between chronic hemolysis, inflammatory response, bone marrow dyserythropoiesis, and iron overload.
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Affiliation(s)
- Anna Zaninoni
- UOS Fisiopatologia delle Anemie, UOC Ematologia, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Elisa Fermo
- UOS Fisiopatologia delle Anemie, UOC Ematologia, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Cristina Vercellati
- UOS Fisiopatologia delle Anemie, UOC Ematologia, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Anna Paola Marcello
- UOS Fisiopatologia delle Anemie, UOC Ematologia, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Wilma Barcellini
- UOS Fisiopatologia delle Anemie, UOC Ematologia, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Paola Bianchi
- UOS Fisiopatologia delle Anemie, UOC Ematologia, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
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8
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Remali J, Aizat WM, Ng CL, Lim YC, Mohamed-Hussein ZA, Fazry S. In silico analysis on the functional and structural impact of Rad50 mutations involved in DNA strand break repair. PeerJ 2020; 8:e9197. [PMID: 32509463 PMCID: PMC7247530 DOI: 10.7717/peerj.9197] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2019] [Accepted: 04/24/2020] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND DNA double strand break repair is important to preserve the fidelity of our genetic makeup after DNA damage. Rad50 is one of the components in MRN complex important for DNA repair mechanism. Rad50 mutations can lead to microcephaly, mental retardation and growth retardation in human. However, Rad50 mutations in human and other organisms have never been gathered and heuristically compared for their deleterious effects. It is important to assess the conserved region in Rad50 and its homolog to identify vital mutations that can affect functions of the protein. METHOD In this study, Rad50 mutations were retrieved from SNPeffect 4.0 database and literature. Each of the mutations was analyzed using various bioinformatic analyses such as PredictSNP, MutPred, SNPeffect 4.0, I-Mutant and MuPro to identify its impact on molecular mechanism, biological function and protein stability, respectively. RESULTS We identified 103 mostly occurred mutations in the Rad50 protein domains and motifs, which only 42 mutations were classified as most deleterious. These mutations are mainly situated at the specific motifs such as Walker A, Q-loop, Walker B, D-loop and signature motif of the Rad50 protein. Some of these mutations were predicted to negatively affect several important functional sites that play important roles in DNA repair mechanism and cell cycle signaling pathway, highlighting Rad50 crucial role in this process. Interestingly, mutations located at non-conserved regions were predicted to have neutral/non-damaging effects, in contrast with previous experimental studies that showed deleterious effects. This suggests that software used in this study may have limitations in predicting mutations in non-conserved regions, implying further improvement in their algorithm is needed. In conclusion, this study reveals the priority of acid substitution associated with the genetic disorders. This finding highlights the vital roles of certain residues such as K42E, C681A/S, CC684R/S, S1202R, E1232Q and D1238N/A located in Rad50 conserved regions, which can be considered for a more targeted future studies.
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Affiliation(s)
- Juwairiah Remali
- Department of Food Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, Selangor, Malaysia
| | - Wan Mohd Aizat
- Institute of Systems Biology (INBIOSIS), Universiti Kebangsaan Malaysia, Bangi, Selangor, Malaysia
| | - Chyan Leong Ng
- Institute of Systems Biology (INBIOSIS), Universiti Kebangsaan Malaysia, Bangi, Selangor, Malaysia
| | - Yi Chieh Lim
- Danish Cancer Society, Research Centre Strand Boulevard, Copenhagen, Denmark
| | - Zeti-Azura Mohamed-Hussein
- Institute of Systems Biology (INBIOSIS), Universiti Kebangsaan Malaysia, Bangi, Selangor, Malaysia
- Department of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, Selangor, Malaysia
| | - Shazrul Fazry
- Department of Food Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, Selangor, Malaysia
- Pusat Penyelidikan Tasik Chini, Fakulti Sains dan Teknologi, Universiti Kebangsaan Malaysia, Bangi, Selangor, Malaysia
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9
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Higuchi K, Yabuki T, Ito M, Kigawa T. Cold shock proteins improve
E. coli
cell‐free synthesis in terms of soluble yields of aggregation‐prone proteins. Biotechnol Bioeng 2020; 117:1628-1639. [DOI: 10.1002/bit.27326] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 03/05/2020] [Accepted: 03/08/2020] [Indexed: 11/10/2022]
Affiliation(s)
- Kae Higuchi
- Laboratory for Cellular Structural BiologyRIKEN Center for Biosystems Dynamics Research Yokohama Kanagawa Japan
| | - Takashi Yabuki
- Laboratory for Cellular Structural BiologyRIKEN Center for Biosystems Dynamics Research Yokohama Kanagawa Japan
- SI Innovation Center, Taiyo Nippon Sanso Corporation Tama‐shi Tokyo Japan
| | - Masahiro Ito
- Laboratory for Cellular Structural BiologyRIKEN Center for Biosystems Dynamics Research Yokohama Kanagawa Japan
| | - Takanori Kigawa
- Laboratory for Cellular Structural BiologyRIKEN Center for Biosystems Dynamics Research Yokohama Kanagawa Japan
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10
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Dongerdiye R, Kamat P, Jain P, Warang P, Devendra R, Wasekar N, Sharma R, Mhaskar K, Madkaikar MR, Manglani MV, Kedar PS. Red cell adenylate kinase deficiency in India: identification of two novel missense mutations (c.71A>G and c.413G>A). J Clin Pathol 2019; 72:393-398. [PMID: 30918013 DOI: 10.1136/jclinpath-2019-205718] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 02/21/2019] [Accepted: 02/25/2019] [Indexed: 02/03/2023]
Abstract
Adenylate kinase (AK) deficiency is a rare erythroenzymopathy associated with hereditary nonspherocytic haemolytic anaemia along with mental/psychomotor retardation in few cases. Diagnosis of AK deficiency depends on the decreased level of enzyme activity in red cell and identification of a mutation in the AK1 gene. Until, only eight mutations causing AK deficiency have been reported in the literature. We are reporting two novel missense mutation (c.71A > G and c.413G > A) detected in the AK1 gene by next-generation sequencing (NGS) in a 6-year-old male child from India. Red cell AK enzyme activity was found to be 30% normal. We have screened a total of 32 family members of the patient and showed reduced red cell enzyme activity and confirm mutations by Sanger's sequencing. On the basis of Sanger sequencing, we suggest that the proband has inherited a mutation in AK1 gene exon 4 c.71A > G (p.Gln24Arg) from paternal family and exon 6 c.413G > A (p.Arg138His) from maternal family. Bioinformatics tools, such as SIFT, Polymorphism Phenotyping v.2, Mutation Taster, MutPred, also confirmed the deleterious effect of both the mutations. Molecular modelling suggests that the structural changes induced by p.Gln24Arg and p.Arg138His are pathogenic variants having a direct impact on the structural arrangement of the region close to the active site of the enzyme. In conclusion, NGS will be the best solution for diagnosis of very rare disorders leading to better management of the disease. This is the first report of the red cell AK deficiency from the Indian population.
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Affiliation(s)
- Rashmi Dongerdiye
- Department of Haematogenetics, National Institute of Immunohaematology, Mumbai, India
| | - Pranoti Kamat
- MCGM Comprehensive Thalassemia Care Pediatric Hematology-Oncology and Bone Marrow Transplantation Centre, Mumbai, India
| | - Punit Jain
- MCGM Comprehensive Thalassemia Care Pediatric Hematology-Oncology and Bone Marrow Transplantation Centre, Mumbai, India
| | - Prashant Warang
- Department of Haematogenetics, National Institute of Immunohaematology, Mumbai, India
| | - Rati Devendra
- Department of Haematogenetics, National Institute of Immunohaematology, Mumbai, India
| | - Nilesh Wasekar
- MCGM Comprehensive Thalassemia Care Pediatric Hematology-Oncology and Bone Marrow Transplantation Centre, Mumbai, India
| | - Ratna Sharma
- MCGM Comprehensive Thalassemia Care Pediatric Hematology-Oncology and Bone Marrow Transplantation Centre, Mumbai, India
| | - Ketaki Mhaskar
- MCGM Comprehensive Thalassemia Care Pediatric Hematology-Oncology and Bone Marrow Transplantation Centre, Mumbai, India
| | | | - Mamta V Manglani
- MCGM Comprehensive Thalassemia Care Pediatric Hematology-Oncology and Bone Marrow Transplantation Centre, Mumbai, India
| | - Prabhakar S Kedar
- Department of Haematogenetics, National Institute of Immunohaematology, Mumbai, India
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11
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Esposito M, Szadocka S, Degiacomi G, Orena BS, Mori G, Piano V, Boldrin F, Zemanová J, Huszár S, Barros D, Ekins S, Lelièvre J, Manganelli R, Mattevi A, Pasca MR, Riccardi G, Ballell L, Mikušová K, Chiarelli LR. A Phenotypic Based Target Screening Approach Delivers New Antitubercular CTP Synthetase Inhibitors. ACS Infect Dis 2017; 3:428-437. [PMID: 28475832 DOI: 10.1021/acsinfecdis.7b00006] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Despite its great potential, the target-based approach has been mostly unsuccessful in tuberculosis drug discovery, while whole cell phenotypic screening has delivered several active compounds. However, for many of these hits, the cellular target has not yet been identified, thus preventing further target-based optimization of the compounds. In this context, the newly validated drug target CTP synthetase PyrG was exploited to assess a target-based approach of already known, but untargeted, antimycobacterial compounds. To this purpose the publically available GlaxoSmithKline antimycobacterial compound set was assayed, uncovering a series of 4-(pyridin-2-yl)thiazole derivatives which efficiently inhibit the Mycobacterium tuberculosis PyrG enzyme activity, one of them showing low activity against the human CTP synthetase. The three best compounds were ATP binding site competitive inhibitors, with Ki values ranging from 3 to 20 μM, but did not show any activity against a small panel of different prokaryotic and eukaryotic kinases, thus demonstrating specificity for the CTP synthetases. Metabolic labeling experiments demonstrated that the compounds directly interfere not only with CTP biosynthesis, but also with other CTP dependent biochemical pathways, such as lipid biosynthesis. Moreover, using a M. tuberculosis pyrG conditional knock-down strain, it was shown that the activity of two compounds is dependent on the intracellular concentration of the CTP synthetase. All these results strongly suggest a role of PyrG as a target of these compounds, thus strengthening the value of this kind of approach for the identification of new scaffolds for drug development.
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Affiliation(s)
- Marta Esposito
- Department
of Biology and Biotechnology “Lazzaro Spallanzani”, University of Pavia, via Ferrata 9, 27100 Pavia, Italy
| | - Sára Szadocka
- Department
of Biochemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynská dolina CH1, 84215 Bratislava, Slovakia
| | - Giulia Degiacomi
- Department
of Molecular Medicine, University of Padova, via Gabelli 63, 35121 Padova, Italy
| | - Beatrice S. Orena
- Department
of Biology and Biotechnology “Lazzaro Spallanzani”, University of Pavia, via Ferrata 9, 27100 Pavia, Italy
| | - Giorgia Mori
- Department
of Biology and Biotechnology “Lazzaro Spallanzani”, University of Pavia, via Ferrata 9, 27100 Pavia, Italy
| | - Valentina Piano
- Department
of Biology and Biotechnology “Lazzaro Spallanzani”, University of Pavia, via Ferrata 9, 27100 Pavia, Italy
| | - Francesca Boldrin
- Department
of Molecular Medicine, University of Padova, via Gabelli 63, 35121 Padova, Italy
| | - Júlia Zemanová
- Department
of Biochemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynská dolina CH1, 84215 Bratislava, Slovakia
| | - Stanislav Huszár
- Department
of Biochemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynská dolina CH1, 84215 Bratislava, Slovakia
| | - David Barros
- Diseases
of the Developing World, GlaxoSmithKline, Calle Severo Ochoa 2, 28760 Tres Cantos, Madrid, Spain
| | - Sean Ekins
- Collaborative Drug Discovery Inc., 1633 Bayshore Highway, Suite 342, Burlingame, California 94010, United States
| | - Joel Lelièvre
- Diseases
of the Developing World, GlaxoSmithKline, Calle Severo Ochoa 2, 28760 Tres Cantos, Madrid, Spain
| | - Riccardo Manganelli
- Department
of Molecular Medicine, University of Padova, via Gabelli 63, 35121 Padova, Italy
| | - Andrea Mattevi
- Department
of Biology and Biotechnology “Lazzaro Spallanzani”, University of Pavia, via Ferrata 9, 27100 Pavia, Italy
| | - Maria Rosalia Pasca
- Department
of Biology and Biotechnology “Lazzaro Spallanzani”, University of Pavia, via Ferrata 9, 27100 Pavia, Italy
| | - Giovanna Riccardi
- Department
of Biology and Biotechnology “Lazzaro Spallanzani”, University of Pavia, via Ferrata 9, 27100 Pavia, Italy
| | - Lluis Ballell
- Diseases
of the Developing World, GlaxoSmithKline, Calle Severo Ochoa 2, 28760 Tres Cantos, Madrid, Spain
| | - Katarína Mikušová
- Department
of Biochemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynská dolina CH1, 84215 Bratislava, Slovakia
| | - Laurent R. Chiarelli
- Department
of Biology and Biotechnology “Lazzaro Spallanzani”, University of Pavia, via Ferrata 9, 27100 Pavia, Italy
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12
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Gao Y, Zhou X, Wang H, Liu R, Ye Q, Zhao Q, Ming Z, Dong H. Immunization with recombinant schistosome adenylate kinase 1 partially protects mice against Schistosoma japonicum infection. Parasitol Res 2017; 116:1665-1674. [PMID: 28455627 DOI: 10.1007/s00436-017-5441-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2017] [Accepted: 04/12/2017] [Indexed: 12/22/2022]
Abstract
Highly effective and safe prophylactic vaccines are urgently needed to sustainably control schistosomiasis, one of the most serious endemic zoonoses in China. In this study, we characterized adenylate kinase 1 from Schistosoma japonicum (SjAK1), a phosphotransferase that regulates cellular energy and metabolism, and evaluated its potential as a recombinant vaccine. Based on real-time quantitative PCR, western blot, and immunolocalization, SjAK1 is active throughout the life of the worm, although its expression is higher in 21-day-old schistosomula, adult worms, and eggs deposited in the host liver. Further, the enzyme accumulates in the eggshell, intestinal epithelium, integument of adult worms and in the vitellaria tissue in female worms. A 594-bp full-length complementary DNA (cDNA) encoding SjAK1 was synthesized from total RNA of 3-day-old schistosomes, and immunization with recombinant SjAK1 reduced worm burden by 50%, decreased the density of eggs deposited in the host liver by 40%, and reduced the area of granulomas in the host liver by 56%. ELISA results showed that recombinant SjAK1 also stimulated Th1 cytokines such as IL-2 and IFN-γ, but not IL-5 and IL-4. Collectively, a recombinant form of the enzyme SjAK1 elicits partial protective immunity against Schistosoma japonicum infection and the induction of Th1 cytokines. Thus, the enzyme has potential as a component of a multivalent vaccine against schistosomiasis.
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Affiliation(s)
- Yanru Gao
- Hubei Province Key Laboratory of Allergy and Immunology, Department of Parasitology, Wuhan University School of Basic Medical Sciences, Wuhan, Hubei Province, 430071, China.,Department of Physiology, School of Basic Medicine Sciences, Hubei University of Science and Technology, Xianning, Hubei Province, 437000, China
| | - Xiaoshan Zhou
- Hubei Province Key Laboratory of Allergy and Immunology, Department of Parasitology, Wuhan University School of Basic Medical Sciences, Wuhan, Hubei Province, 430071, China
| | - Huan Wang
- Hubei Province Key Laboratory of Allergy and Immunology, Department of Parasitology, Wuhan University School of Basic Medical Sciences, Wuhan, Hubei Province, 430071, China
| | - Rong Liu
- Hubei Province Key Laboratory of Allergy and Immunology, Department of Parasitology, Wuhan University School of Basic Medical Sciences, Wuhan, Hubei Province, 430071, China
| | - Qing Ye
- Renmin Hospital, Wuhan University, Wuhan, Hubei Province, 430000, China
| | - Qinping Zhao
- Hubei Province Key Laboratory of Allergy and Immunology, Department of Parasitology, Wuhan University School of Basic Medical Sciences, Wuhan, Hubei Province, 430071, China
| | - Zhenping Ming
- Hubei Province Key Laboratory of Allergy and Immunology, Department of Parasitology, Wuhan University School of Basic Medical Sciences, Wuhan, Hubei Province, 430071, China
| | - Huifen Dong
- Hubei Province Key Laboratory of Allergy and Immunology, Department of Parasitology, Wuhan University School of Basic Medical Sciences, Wuhan, Hubei Province, 430071, China.
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13
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De la Fuente IM, Cortés JM, Valero E, Desroches M, Rodrigues S, Malaina I, Martínez L. On the dynamics of the adenylate energy system: homeorhesis vs homeostasis. PLoS One 2014; 9:e108676. [PMID: 25303477 PMCID: PMC4193753 DOI: 10.1371/journal.pone.0108676] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Accepted: 09/03/2014] [Indexed: 11/20/2022] Open
Abstract
Biochemical energy is the fundamental element that maintains both the adequate turnover of the biomolecular structures and the functional metabolic viability of unicellular organisms. The levels of ATP, ADP and AMP reflect roughly the energetic status of the cell, and a precise ratio relating them was proposed by Atkinson as the adenylate energy charge (AEC). Under growth-phase conditions, cells maintain the AEC within narrow physiological values, despite extremely large fluctuations in the adenine nucleotides concentration. Intensive experimental studies have shown that these AEC values are preserved in a wide variety of organisms, both eukaryotes and prokaryotes. Here, to understand some of the functional elements involved in the cellular energy status, we present a computational model conformed by some key essential parts of the adenylate energy system. Specifically, we have considered (I) the main synthesis process of ATP from ADP, (II) the main catalyzed phosphotransfer reaction for interconversion of ATP, ADP and AMP, (III) the enzymatic hydrolysis of ATP yielding ADP, and (IV) the enzymatic hydrolysis of ATP providing AMP. This leads to a dynamic metabolic model (with the form of a delayed differential system) in which the enzymatic rate equations and all the physiological kinetic parameters have been explicitly considered and experimentally tested in vitro. Our central hypothesis is that cells are characterized by changing energy dynamics (homeorhesis). The results show that the AEC presents stable transitions between steady states and periodic oscillations and, in agreement with experimental data these oscillations range within the narrow AEC window. Furthermore, the model shows sustained oscillations in the Gibbs free energy and in the total nucleotide pool. The present study provides a step forward towards the understanding of the fundamental principles and quantitative laws governing the adenylate energy system, which is a fundamental element for unveiling the dynamics of cellular life.
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Affiliation(s)
- Ildefonso M. De la Fuente
- Institute of Parasitology and Biomedicine “López-Neyra”, CSIC, Granada, Spain
- Department of Mathematics, University of the Basque Country UPV/EHU, Leioa, Spain
- Unit of Biophysics (CSIC, UPV/EHU), and Department of Biochemistry and Molecular Biology University of the Basque Country, Bilbao, Spain
- Biocruces Health Research Institute, Hospital Universitario de Cruces, Barakaldo, Spain
| | - Jesús M. Cortés
- Biocruces Health Research Institute, Hospital Universitario de Cruces, Barakaldo, Spain
- Ikerbasque: The Basque Foundation for Science, Bilbao, Basque Country, Spain
| | - Edelmira Valero
- Department of Physical Chemistry, School of Industrial Engineering, University of Castilla-La Mancha, Albacete, Spain
| | | | - Serafim Rodrigues
- School of Computing and Mathematics, University of Plymouth, Plymouth, United Kingdom
| | - Iker Malaina
- Biocruces Health Research Institute, Hospital Universitario de Cruces, Barakaldo, Spain
- Department of Physiology, University of the Basque Country UPV/EHU, Bilbao, Spain
| | - Luis Martínez
- Department of Mathematics, University of the Basque Country UPV/EHU, Leioa, Spain
- Biocruces Health Research Institute, Hospital Universitario de Cruces, Barakaldo, Spain
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14
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Balasubramaniam S, Duley JA, Christodoulou J. Inborn errors of purine metabolism: clinical update and therapies. J Inherit Metab Dis 2014; 37:669-86. [PMID: 24972650 DOI: 10.1007/s10545-014-9731-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Revised: 05/27/2014] [Accepted: 06/02/2014] [Indexed: 12/20/2022]
Abstract
Inborn errors of purine metabolism exhibit broad neurological, immunological, haematological and renal manifestations. Limited awareness of the phenotypic spectrum, the recent descriptions of newer disorders and considerable genetic heterogeneity, have contributed to long diagnostic odysseys for affected individuals. These enzymes are widely but not ubiquitously distributed in human tissues and are crucial for synthesis of essential nucleotides, such as ATP, which form the basis of DNA and RNA, oxidative phosphorylation, signal transduction and a range of molecular synthetic processes. Depletion of nucleotides or accumulation of toxic intermediates contributes to the pathogenesis of these disorders. Maintenance of cellular nucleotides depends on the three aspects of metabolism of purines (and related pyrimidines): de novo synthesis, catabolism and recycling of these metabolites. At present, treatments for the clinically significant defects of the purine pathway are restricted: purine 5'-nucleotidase deficiency with uridine; familial juvenile hyperuricaemic nephropathy (FJHN), adenine phosphoribosyl transferase (APRT) deficiency, hypoxanthine phosphoribosyl transferase (HPRT) deficiency and phosphoribosyl-pyrophosphate synthetase superactivity (PRPS) with allopurinol; adenosine deaminase (ADA) and purine nucleoside phosphorylase (PNP) deficiencies have been treated by bone marrow transplantation (BMT), and ADA deficiency with enzyme replacement with polyethylene glycol (PEG)-ADA, or erythrocyte-encapsulated ADA; myeloadenylate deaminase (MADA) and adenylosuccinate lyase (ADSL) deficiencies have had trials of oral ribose; PRPS, HPRT and adenosine kinase (ADK) deficiencies with S-adenosylmethionine; and molybdenum cofactor deficiency of complementation group A (MOCODA) with cyclic pyranopterin monophosphate (cPMP). In this review we describe the known inborn errors of purine metabolism, their phenotypic presentations, established diagnostic methodology and recognised treatment options.
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Affiliation(s)
- Shanti Balasubramaniam
- Metabolic Unit, Princess Margaret Hospital, Roberts Road, Subiaco, Perth, WA, 6008, Australia
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15
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Parvaneh N, Quartier P, Rostami P, Casanova JL, de Lonlay P. Inborn errors of metabolism underlying primary immunodeficiencies. J Clin Immunol 2014; 34:753-71. [PMID: 25081841 DOI: 10.1007/s10875-014-0076-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 07/02/2014] [Indexed: 01/19/2023]
Abstract
A number of inborn errors of metabolism (IEM) have been shown to result in predominantly immunologic phenotypes, manifesting in part as inborn errors of immunity. These phenotypes are mostly caused by defects that affect the (i) quality or quantity of essential structural building blocks (e.g., nucleic acids, and amino acids), (ii) cellular energy economy (e.g., glucose metabolism), (iii) post-translational protein modification (e.g., glycosylation) or (iv) mitochondrial function. Presenting as multisystemic defects, they also affect innate or adaptive immunity, or both, and display various types of immune dysregulation. Specific and potentially curative therapies are available for some of these diseases, whereas targeted treatments capable of inducing clinical remission are available for others. We will herein review the pathogenesis, diagnosis, and treatment of primary immunodeficiencies (PIDs) due to underlying metabolic disorders.
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Affiliation(s)
- Nima Parvaneh
- Research Center for Immunodeficiencies, Tehran University of Medical Sciences, Tehran, Iran,
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16
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Koralkova P, van Solinge WW, van Wijk R. Rare hereditary red blood cell enzymopathies associated with hemolytic anemia - pathophysiology, clinical aspects, and laboratory diagnosis. Int J Lab Hematol 2014; 36:388-97. [DOI: 10.1111/ijlh.12223] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Accepted: 02/28/2014] [Indexed: 02/06/2023]
Affiliation(s)
- P. Koralkova
- Department of Biology; Faculty of Medicine and Dentistry; Palacky University; Olomouc Czech Republic
| | - W. W. van Solinge
- Department of Clinical Chemistry and Haematology; University Medical Center Utrecht; Utrecht the Netherlands
| | - R. van Wijk
- Department of Clinical Chemistry and Haematology; University Medical Center Utrecht; Utrecht the Netherlands
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17
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Fu C, Peng Y, Liao X, Guo C, Lin D. ¹H, ¹³C, ¹⁵N backbone and side-chain resonance assignments of the human adenylate kinase 1 in apo form. BIOMOLECULAR NMR ASSIGNMENTS 2013; 7:155-158. [PMID: 22706932 DOI: 10.1007/s12104-012-9399-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2012] [Accepted: 06/01/2012] [Indexed: 06/01/2023]
Abstract
AK1 (Adenylate Kinase 1) plays crucial roles in processes such as cellular phosphotransfer networks, neuronal maturation and regeneration, gating of ABC transporter CFTR, tumor cell metabolism and myocardial energetic homeostasis. Here we report (1)H, (15)N and (13)C backbone and side-chain resonance assignments of the human AK1 protein in apo form. This work lays the essential basis for the further structure determination of hAK1.
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Affiliation(s)
- Cuiping Fu
- The Key Laboratory for Chemical Biology of Fujian Province, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
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18
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Dzeja P, Terzic A. Adenylate kinase and AMP signaling networks: metabolic monitoring, signal communication and body energy sensing. Int J Mol Sci 2009; 10:1729-1772. [PMID: 19468337 PMCID: PMC2680645 DOI: 10.3390/ijms10041729] [Citation(s) in RCA: 298] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2009] [Revised: 03/26/2009] [Accepted: 04/02/2009] [Indexed: 12/20/2022] Open
Abstract
Adenylate kinase and downstream AMP signaling is an integrated metabolic monitoring system which reads the cellular energy state in order to tune and report signals to metabolic sensors. A network of adenylate kinase isoforms (AK1-AK7) are distributed throughout intracellular compartments, interstitial space and body fluids to regulate energetic and metabolic signaling circuits, securing efficient cell energy economy, signal communication and stress response. The dynamics of adenylate kinase-catalyzed phosphotransfer regulates multiple intracellular and extracellular energy-dependent and nucleotide signaling processes, including excitation-contraction coupling, hormone secretion, cell and ciliary motility, nuclear transport, energetics of cell cycle, DNA synthesis and repair, and developmental programming. Metabolomic analyses indicate that cellular, interstitial and blood AMP levels are potential metabolic signals associated with vital functions including body energy sensing, sleep, hibernation and food intake. Either low or excess AMP signaling has been linked to human disease such as diabetes, obesity and hypertrophic cardiomyopathy. Recent studies indicate that derangements in adenylate kinase-mediated energetic signaling due to mutations in AK1, AK2 or AK7 isoforms are associated with hemolytic anemia, reticular dysgenesis and ciliary dyskinesia. Moreover, hormonal, food and antidiabetic drug actions are frequently coupled to alterations of cellular AMP levels and associated signaling. Thus, by monitoring energy state and generating and distributing AMP metabolic signals adenylate kinase represents a unique hub within the cellular homeostatic network.
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Affiliation(s)
- Petras Dzeja
- Author to whom correspondence should be addressed; E-mail:
(P.D.)
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19
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Liu Y, Schanze KS. Conjugated polyelectrolyte based real-time fluorescence assay for adenylate kinase. Anal Chem 2009; 81:231-9. [PMID: 19117453 DOI: 10.1021/ac801908f] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Addition of adenosine 5'-triphosphate (ATP) to a solution of the anionic conjugated polyelectrolyte PPECO2 and copper(II) ion (Cu2+) recovers the Cu2+-quenched fluorescence of PPECO(2) to a significantly greater extent compared with the addition of adenosine 5'-diphosphate (ADP) or adenosine 5'-monophosphate (AMP) at the same concentration levels. Taking advantage of the differential response of the PPECO2-Cu2+ system to ATP, ADP and AMP, we have developed fluorescence turn-off and turn-on assays that monitor the catalytic activity of adenylate kinase (ADK) in the equilibrium transphosphorylation reaction (ATP + AMP <--> 2ADP). The fluorescence turn-on and turn-off assays monitor the forward and reverse transphosphorylation reactions, respectively. The forward assay operates with ATP substrate present at the submillimolar concentration range and offers a straightforward and rapid detection of ADK catalytic activity with the enzyme present in the nanomolar range, in either end-point or real-time formats. The real-time fluorescence intensity from PPECO2 can be converted to substrate (ATP) concentration in the forward reaction assay by using an ex-situ calibration curve, allowing ADK catalyzed reaction rates and kinetic parameters to be determined. ADK activation by Mg2+ and inhibition by Ag+ and product are analyzed using the optimized assay system. Non-specific interactions are observed between the assay complex and other proteins, but the signal response to the ADK assay is demonstrated to mainly arise from the specific enzyme catalyzed transphosphorylation reaction.
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Affiliation(s)
- Yan Liu
- Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, Florida 32611-7200, USA
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