TY - JOUR AU - Szabó, Eszter AU - Nagy, Bálint AU - Czajlik, András AU - Komlódi, Tímea AU - Ozohanics, Olivér AU - Tretter, László AU - Ambrus, Attila TI - Mitochondrial Alpha-Keto Acid Dehydrogenase Complexes: Recent Developments on Structure and Function in Health and Disease JF - SUB-CELLULAR BIOCHEMISTRY J2 - SUB-CELL BIOCHEM VL - 104 PY - 2024 SP - 295 EP - 381 PG - 87 SN - 0306-0225 DO - 10.1007/978-3-031-58843-3_13 UR - https://m2.mtmt.hu/api/publication/35134753 ID - 35134753 LA - English DB - MTMT ER - TY - JOUR AU - Szabó, Eszter AU - Ambrus, Attila TI - Lipoamide dehydrogenase (LADH) deficiency: medical perspectives of the structural and functional characterization of LADH and its pathogenic variants JF - BIOLOGIA FUTURA J2 - BIOL FUTURA VL - 74 PY - 2023 IS - 1-2 SP - 109 EP - 118 PG - 10 SN - 2676-8615 DO - 10.1007/s42977-023-00155-6 UR - https://m2.mtmt.hu/api/publication/33686272 ID - 33686272 N1 - Cited By :4 Export Date: 15 January 2025 Correspondence Address: Ambrus, A.; Department of Biochemistry, 37-47 Tuzolto St., Hungary; email: ambrus.attila@med.semmelweis-univ.hu LA - English DB - MTMT ER - TY - JOUR AU - Wittinger, Soma AU - Szabó, Eszter AU - Ambrus, Attila TI - A mitokondriális α-ketosav-dehidrogenáz enzimkomplexek működése, szerkezete és szabályozása JF - BIOKÉMIA: A MAGYAR BIOKÉMIAI EGYESÜLET FOLYÓIRATA J2 - BIOKÉMIA VL - 47 PY - 2023 IS - 1 SP - 19 EP - 31 PG - 13 SN - 0133-8455 UR - https://m2.mtmt.hu/api/publication/33749248 ID - 33749248 LA - Hungarian DB - MTMT ER - TY - JOUR AU - Szabó, Eszter AU - Nemes-Nikodém, Éva AU - Vass, Krisztina Rubina AU - Zámbó, Zsófia Melinda AU - Zrupko, E. AU - Törőcsik, Beáta AU - Ozohanics, Olivér AU - Nagy, Bálint AU - Ambrus, Attila TI - Structural and Biochemical Investigation of Selected Pathogenic Mutants of the Human Dihydrolipoamide Dehydrogenase JF - INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES J2 - INT J MOL SCI VL - 24 PY - 2023 IS - 13 PG - 23 SN - 1661-6596 DO - 10.3390/ijms241310826 UR - https://m2.mtmt.hu/api/publication/34075046 ID - 34075046 N1 - Cited By :1 Export Date: 15 January 2025 Correspondence Address: Ambrus, A.; Department of Biochemistry, 37-47 Tuzolto St, Hungary; email: ambrus.attila@med.semmelweis-univ.hu AB - Clinically relevant disease-causing variants of the human dihydrolipoamide dehydrogenase (hLADH, hE3), a common component of the mitochondrial α-keto acid dehydrogenase complexes, were characterized using a multipronged approach to unravel the molecular pathomechanisms that underlie hLADH deficiency. The G101del and M326V substitutions both reduced the protein stability and triggered the disassembly of the functional/obligate hLADH homodimer and significant FAD losses, which altogether eventually manifested in a virtually undetectable catalytic activity in both cases. The I12T-hLADH variant proved also to be quite unstable, but managed to retain the dimeric enzyme form; the LADH activity, both in the forward and reverse catalytic directions and the affinity for the prosthetic group FAD were both significantly compromised. None of the above three variants lent themselves to an in-depth structural analysis via X-ray crystallography due to inherent protein instability. Crystal structures at 2.89 and 2.44 Å resolutions were determined for the I318T- and I358T-hLADH variants, respectively; structure analysis revealed minor conformational perturbations, which correlated well with the residual LADH activities, in both cases. For the dimer interface variants G426E-, I445M-, and R447G-hLADH, enzyme activities and FAD loss were determined and compared against the previously published structural data. © 2023 by the authors. LA - English DB - MTMT ER - TY - JOUR AU - Szabó, Eszter AU - Ambrus, Attila TI - Current Approaches in Molecular Enzymology JF - LIFE-BASEL J2 - LIFE-BASEL VL - 12 PY - 2022 PG - 3 SN - 2075-1729 DO - 10.3390/life12030336 UR - https://m2.mtmt.hu/api/publication/32707799 ID - 32707799 N1 - Export Date: 22 December 2022 Correspondence Address: Ambrus, A.; Department of Biochemistry, Hungary; email: ambrus.attila@med.semmelweis-univ.hu AB - Enzymes are the main executioners of living organisms [...] LA - English DB - MTMT ER - TY - JOUR AU - Nagy, Bálint AU - Polak, Martin AU - Ozohanics, Olivér AU - Zámbó, Zsófia Melinda AU - Szabó, Eszter AU - Hubert, Ágnes AU - Jordan, Frank AU - Novaček, Jiří AU - Ádám, Veronika AU - Ambrus, Attila TI - Structure of the dihydrolipoamide succinyltransferase (E2) component of the human alpha-ketoglutarate dehydrogenase complex (hKGDHc) revealed by cryo-EM and cross-linking mass spectrometry. Implications for the overall hKGDHc structure. TS - Implications for the overall hKGDHc structure. JF - BIOCHIMICA ET BIOPHYSICA ACTA-GENERAL SUBJECTS J2 - BBA-GEN SUBJECTS VL - 1865 PY - 2021 IS - 6 PG - 17 SN - 0304-4165 DO - 10.1016/j.bbagen.2021.129889 UR - https://m2.mtmt.hu/api/publication/31917407 ID - 31917407 N1 - Department of Biochemistry, Institute of Biochemistry and Molecular Biology, Semmelweis University, Budapest, Hungary Central European Institute of Technology, Masaryk University, Brno, Czech Republic Department of Chemistry, Rutgers, The State University of New Jersey, Newark, NJ, United States Export Date: 18 March 2021 CODEN: BBGSB Correspondence Address: Ambrus, A.; Department of Biochemistry, Budapest, 37-47 Tuzolto St., Hungary; email: ambrus.attila@med.semmelweis-univ.hu Funding details: National Institutes of Health, NIH, GM050380, LM2018127, R15-GM116077 Funding details: Magyar Tudományos Akadémia, MTA, 02001 Funding details: Semmelweis Egyetem Funding details: Ministerstvo Školství, Mládeže a Tělovýchovy, MŠMT Funding details: Hungarian Scientific Research Fund, OTKA Funding details: Magyar Tudományos Akadémia, MTA Funding details: Hungarian Scientific Research Fund, OTKA, 112230 Funding details: 61826 690289, 61830Z0100 EATV Funding details: 2017-1.2.1-NKP-2017-00002, KTIA_13_NAP-A-III/6 Funding text 1: Financial support was secured from the Hungarian Academy of Sciences (MTA grant 02001 to V.A-V.), Hungarian Scientific Research Fund (OTKA grant 112230 to V.A-V.), Hungarian Brain Research Program (grants KTIA_13_NAP-A-III/6 and 2017-1.2.1-NKP-2017-00002 to V.A-V.), Young Investigator Research Grants of Semmelweis University and Chemical Works of Gedeon Richter Plc. (to A.A.), Hungarian Higher Education Institution Excellence Program (FIKP grants 61826 690289 EATV and 61830Z0100 EATV to A.A.) and National Institutes of Health (grants GM050380 and R15-GM116077 to F. J.). CIISB research infrastructure project LM2018127 funded by MEYS CR is gratefully acknowledged for the financial support of the measurements at the CF Cryo-electron Microscopy and Tomography. Department of Biochemistry, Institute of Biochemistry and Molecular Biology, Semmelweis University, Budapest, Hungary Central European Institute of Technology, Masaryk University, Brno, Czech Republic Department of Chemistry, Rutgers, The State University of New Jersey, Newark, NJ, United States Export Date: 29 March 2021 CODEN: BBGSB Correspondence Address: Ambrus, A.; Department of Biochemistry, Budapest, 37-47 Tuzolto St., Hungary; email: ambrus.attila@med.semmelweis-univ.hu Funding details: National Institutes of Health, NIH, GM050380, LM2018127, R15-GM116077 Funding details: Magyar Tudományos Akadémia, MTA, 02001 Funding details: Ministerstvo Školství, Mládeže a Tělovýchovy, MŠMT Funding details: Hungarian Scientific Research Fund, OTKA Funding details: Magyar Tudományos Akadémia, MTA Funding details: Hungarian Scientific Research Fund, OTKA, 112230 Funding details: 61826 690289, 61830Z0100 EATV Funding text 1: Financial support was secured from the Hungarian Academy of Sciences (MTA grant 02001 to V.A-V.), Hungarian Scientific Research Fund (OTKA grant 112230 to V.A-V.), Hungarian Brain Research Program (grants KTIA_13_NAP-A-III/6 and 2017-1.2.1-NKP-2017-00002 to V.A-V.), Young Investigator Research Grants of Semmelweis University and Chemical Works of Gedeon Richter Plc . (to A.A.), Hungarian Higher Education Institution Excellence Program (FIKP grants 61826 690289 EATV and 61830Z0100 EATV to A.A.) and National Institutes of Health (grants GM050380 and R15-GM116077 to F. J.). CIISB research infrastructure project LM2018127 funded by MEYS CR is gratefully acknowledged for the financial support of the measurements at the CF Cryo-electron Microscopy and Tomography. Department of Biochemistry, Institute of Biochemistry and Molecular Biology, Semmelweis University, Budapest, Hungary Central European Institute of Technology, Masaryk University, Brno, Czech Republic Department of Chemistry, Rutgers, The State University of New Jersey, Newark, NJ, United States Export Date: 30 March 2021 CODEN: BBGSB Correspondence Address: Ambrus, A.; Department of Biochemistry, Budapest, 37-47 Tuzolto St., Hungary; email: ambrus.attila@med.semmelweis-univ.hu Funding details: National Institutes of Health, NIH, GM050380, LM2018127, R15-GM116077 Funding details: Magyar Tudományos Akadémia, MTA, 02001 Funding details: Ministerstvo Školství, Mládeže a Tělovýchovy, MŠMT Funding details: Hungarian Scientific Research Fund, OTKA Funding details: Magyar Tudományos Akadémia, MTA Funding details: Hungarian Scientific Research Fund, OTKA, 112230 Funding details: 61826 690289, 61830Z0100 EATV Funding text 1: Financial support was secured from the Hungarian Academy of Sciences (MTA grant 02001 to V.A-V.), Hungarian Scientific Research Fund (OTKA grant 112230 to V.A-V.), Hungarian Brain Research Program (grants KTIA_13_NAP-A-III/6 and 2017-1.2.1-NKP-2017-00002 to V.A-V.), Young Investigator Research Grants of Semmelweis University and Chemical Works of Gedeon Richter Plc . (to A.A.), Hungarian Higher Education Institution Excellence Program (FIKP grants 61826 690289 EATV and 61830Z0100 EATV to A.A.) and National Institutes of Health (grants GM050380 and R15-GM116077 to F. J.). CIISB research infrastructure project LM2018127 funded by MEYS CR is gratefully acknowledged for the financial support of the measurements at the CF Cryo-electron Microscopy and Tomography. AB - The human mitochondrial alpha-ketoglutarate dehydrogenase complex (hKGDHc) converts KG to succinyl-CoA and NADH. Malfunction of and reactive oxygen species generation by the hKGDHc as well as its E1-E2 subcomplex are implicated in neurodegenerative disorders, ischemia-reperfusion injury, E3-deficiency and cancers.We performed cryo-EM, cross-linking mass spectrometry (CL-MS) and molecular modeling analyses to determine the structure of the E2 component of the hKGDHc (hE2k); hE2k transfers a succinyl group to CoA and forms the structural core of hKGDHc. We also assessed the overall structure of the hKGDHc by negative-stain EM and modeling.We report the 2.9 Å resolution cryo-EM structure of the hE2k component. The cryo-EM map comprises density for hE2k residues 151-386 - the entire (inner) core catalytic domain plus a few additional residues -, while residues 1-150 are not observed due to the inherent flexibility of the N-terminal region. The structure of the latter segment was also determined by CL-MS and homology modeling. Negative-stain EM on in vitro assembled hKGDHc and previous data were used to build a putative overall structural model of the hKGDHc.The E2 core of the hKGDHc is composed of 24 hE2k chains organized in octahedral (8 × 3 type) assembly. Each lipoyl domain is oriented towards the core domain of an adjacent chain in the hE2k homotrimer. hE1k and hE3 are most likely tethered at the edges and faces, respectively, of the cubic hE2k assembly.The revealed structural information will support the future pharmacologically targeting of the hKGDHc. LA - English DB - MTMT ER - TY - JOUR AU - Nagy, Bálint AU - Martin, Polak AU - Ozohanics, Olivér AU - Zámbó, Zsófia Melinda AU - Szabó, Eszter AU - Hubert, Ágnes AU - Frank, Jordan AU - Jiri, Novacek AU - Ádám, Veronika AU - Ambrus, Attila TI - Structure of the dihydrolipoamide succinyltransferase (E2) component of the human alpha-ketoglutarate dehydrogenase complex (hKGDHc) revealed by cryo-EM and cross-linking mass spectrometry: Implications for the overall hKGDHc structure JF - PROTEIN SCIENCE J2 - PROTEIN SCI VL - 30 PY - 2021 IS - S1 SP - 171 EP - 171 PG - 1 SN - 0961-8368 DO - 10.1002/pro.4191 UR - https://m2.mtmt.hu/api/publication/33081530 ID - 33081530 N1 - Award Winners and Abstracts of the 35th Anniversary Symposium of The Protein Society, July 7–14, 2021 | Virtual LA - English DB - MTMT ER - TY - THES AU - Szabó, Eszter TI - A humán dihidrolipoamid-dehidrogenáz patogén mutánsainak szerkezetanalízise PY - 2020 DO - 10.14753/SE.2020.2387 UR - https://m2.mtmt.hu/api/publication/31932299 ID - 31932299 LA - Hungarian DB - MTMT ER - TY - JOUR AU - Nagy, Bálint AU - Polak, Martin AU - Ozohanics, Olivér AU - Zámbó, Zsófia Melinda AU - Szabó, Eszter AU - Hubert, Ágnes AU - Jordan, Frank AU - Novacek, Jiri AU - Ádám, Veronika AU - Ambrus, Attila TI - Structure of the Dihydrolipoamide Succinyltransferase (E2) Component of the Human α-ketoglutarate dehydrogenase complex (hKGDHc) revealed by cryo-EM and Cross-linking mass spectrometry: Implications for the overall hKGDHc structure JF - FREE RADICAL BIOLOGY AND MEDICINE J2 - FREE RADICAL BIO MED VL - 159 PY - 2020 IS - Suppl. 1 SP - S29 EP - S30 SN - 0891-5849 DO - 10.1016/j.freeradbiomed.2020.10.088 UR - https://m2.mtmt.hu/api/publication/33081442 ID - 33081442 LA - English DB - MTMT ER - TY - JOUR AU - Szabó, Eszter AU - Wilk, Piotr AU - Nagy, Bálint AU - Zámbó, Zsófia Melinda AU - Bui, Dávid AU - Weichsel, Andrzej AU - Arjunan, Palaniappa AU - Törőcsik, Beáta AU - Hubert, Agnes AU - Furey, William AU - Montfort, William R AU - Jordan, Frank AU - Weiss, Manfred S AU - Ádám, Veronika AU - Ambrus, Attila TI - Underlying molecular alterations in human dihydrolipoamide dehydrogenase deficiency revealed by structural analyses of disease-causing enzyme variants JF - HUMAN MOLECULAR GENETICS J2 - HUM MOL GENET VL - 28 PY - 2019 IS - 20 SP - 3339 EP - 3354 PG - 16 SN - 0964-6906 DO - 10.1093/hmg/ddz177 UR - https://m2.mtmt.hu/api/publication/30799456 ID - 30799456 AB - Human dihydrolipoamide dehydrogenase (hLADH, hE3) deficiency (OMIM# 246900) is an often prematurely lethal genetic disease usually caused by inactive or partially inactive hE3 variants. Here we report the crystal structure of wild-type hE3 at an unprecedented high resolution of 1.75 Å and the structures of six disease-causing hE3 variants at resolutions ranging from 1.44 to 2.34 Å. P453L proved to be the most deleterious substitution in structure as aberrations extensively compromised the active site. The most prevalent G194C-hE3 variant primarily exhibited structural alterations close to the substitution site, whereas the nearby cofactor-binding residues were left unperturbed. The G426E substitution mainly interfered with the local charge distribution introducing dynamics to the substitution site in the dimer interface; G194C and G426E both led to minor structural changes. The R460G, R447G, and I445M substitutions all perturbed a solvent accessible channel, the so-called H+/H2O channel, leading to the active site. Molecular pathomechanisms of enhanced reactive oxygen species (ROS) generation and impaired binding to multienzyme complexes were also addressed according to the structural data for the relevant mutations. In summary, we present here for the first time a comprehensive study that links three-dimensional structures of disease-causing hE3 variants to residual hLADH activities, altered capacities for ROS generation, compromised affinities for multienzyme complexes, and eventually clinical symptoms. Our results may serve as useful starting points for future therapeutic intervention approaches. LA - English DB - MTMT ER -