TY  - JOUR
AU  - Piroli, Gerardo G.
AU  - Manuel, Allison M.
AU  - McCain, Richard S.
AU  - Smith, Holland H.
AU  - Ozohanics, Olivér
AU  - Mellid, Sara
AU  - Cox, J. Hunter
AU  - Cotham, William E.
AU  - Walla, Michael D.
AU  - Cascón, Alberto
AU  - Ambrus, Attila
AU  - Frizzell, Norma
TI  - Defective function of α-ketoglutarate dehydrogenase exacerbates mitochondrial ATP deficits during complex I deficiency
JF  - REDOX BIOLOGY
J2  - REDOX BIOL
VL  - 67
PY  - 2023
PG  - 17
SN  - 2213-2317
DO  - 10.1016/j.redox.2023.102932
UR  - https://m2.mtmt.hu/api/publication/34213151
ID  - 34213151
N1  - Department of Pharmacology, Physiology & Neuroscience, School of Medicine, University of South Carolina, Columbia, SC 29209, United States            
            Department of Biochemistry, Institute of Biochemistry and Molecular Biology, Semmelweis University, Budapest, Hungary            
            Hereditary Endocrine Cancer Group, Spanish National Cancer Research Centre (CNIO), Madrid, 28029, Spain            
            Mass Spectrometry Center, Department of Chemistry & Biochemistry, University of South Carolina, Columbia, SC 29205, United States            
            Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, 28029, Spain            
            Cited By :2            
            Export Date: 23 April 2024            
            Correspondence Address: Frizzell, N.; Department of Pharmacology, 6439 Garners Ferry Road, United States; email: norma.frizzell@uscmed.sc.edu
LA  - English
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  - Export Date: 1 September 2023            
            Correspondence Address: Ambrus, A.; Department of Biochemistry, 37-47 Tuzolto St, Hungary; email: ambrus.attila@med.semmelweis-univ.hu            
            Funding details: TKP2021-EGA-25, ÚNKP-19-3-III-SE-17            
            Funding details: Horizon 2020 Framework Programme, H2020, PID18322            
            Funding details: Helmholtz-Zentrum Berlin für Materialien und Energie, HZB            
            Funding details: Semmelweis Egyetem, STIA-OTKA-2021            
            Funding details: Hungarian Scientific Research Fund, OTKA, 143627            
            Funding details: Helmholtz-Zentrum für Umweltforschung, UFZ            
            Funding details: Nemzeti Kutatási, Fejlesztési és Innovaciós Alap, NKFIA            
            Funding text 1: This research was funded by the Hungarian Brain Research Program 2 (2017-1.2.1-NKP-2017-00002 grant, to Vera Adam-Vizi), Semmelweis University (STIA-OTKA-2021 grant, to A.A.), Hungarian Scientific Research Fund (OTKA grant 143627, to A.A.), Ministry of Innovation and Technology of Hungary (TKP2021-EGA-25 grant, to A.A. and ÚNKP-19-3-III-SE-17 grant of the New National Excellence Program, to E.S.; project no. TKP2021-EGA-25 has been implemented with the support provided by the Ministry of Innovation and Technology of Hungary from the National Research, Development and Innovation Fund, financed under the TKP2021-EGA funding scheme), and European Union’s Horizon 2020 Research and Innovation Programme (Structural Biology Research Infrastructures for Translational Research and Discovery, iNEXT-Discovery PID18322 and MX-212-00269-ST (Helmholtz Zentrum Berlin/CALIPSO) grants, both to A.A.).            
            Funding text 2: The authors gratefully acknowledge the generous support from Vera Adam-Vizi (Semmelweis University) and Manfred S. Weiss (Helmholtz-Zentrum Berlin).
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  - 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  - 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  - Export Date: 12 May 2023            
            Correspondence Address: Ambrus, A.; Department of Biochemistry, 37-47 Tuzolto St., Hungary; email: ambrus.attila@med.semmelweis-univ.hu            
            Funding details: TKP2021-EGA-25            
            Funding details: Nemzeti Kutatási, Fejlesztési és Innovaciós Alap, NKFIA            
            Funding details: Semmelweis Egyetem, STIA-OTKA-2021            
            Funding details: Hungarian Scientific Research Fund, OTKA, 143627            
            Funding text 1: Open access funding provided by Semmelweis University. This research was funded by the Hungarian Brain Research Program 2 (2017-1.2.1-NKP-2017-00002 grant, to Vera Adam-Vizi, Semmelweis University), Semmelweis University (STIA-OTKA-2021 grant, to A.A.), Hungarian Scientific Research Fund (OTKA grant 143627, to A.A.) and Ministry of Innovation and Technology of Hungary (TKP2021-EGA-25 grant, to A.A.). Project no. TKP2021-EGA-25 has been implemented with the support provided by the Ministry of Innovation and Technology of Hungary from the National Research, Development and Innovation Fund, financed under the TKP2021-EGA funding scheme.
LA  - English
DB  - MTMT
ER  - 

TY  - JOUR
AU  - Ozohanics, Olivér
AU  - Zhang, Xu
AU  - Nemeria, Natalia S.
AU  - Ambrus, Attila
AU  - Jordan, Frank
TI  - Probing the E1o-E2o and E1a-E2o Interactions in Binary Subcomplexes of the Human 2-Oxoglutarate Dehydrogenase and 2-Oxoadipate Dehydrogenase Complexes by Chemical Cross-Linking Mass Spectrometry and Molecular Dynamics Simulation
JF  - INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
J2  - INT J MOL SCI
VL  - 24
PY  - 2023
IS  - 5
PG  - 21
SN  - 1661-6596
DO  - 10.3390/ijms24054555
UR  - https://m2.mtmt.hu/api/publication/33684822
ID  - 33684822
N1  - Department of Biochemistry, Institute of Biochemistry and Molecular Biology, Semmelweis University, Budapest, 1094, Hungary            
            Department of Chemistry, Rutgers University, Newark, NJ 07102, United States            
            Export Date: 15 May 2023            
            Correspondence Address: Ambrus, A.; Department of Biochemistry, Hungary; email: ambrus.attila@med.semmelweis-univ.hu            
            Correspondence Address: Jordan, F.; Department of Chemistry, United States; email: frjordan@newark.rutgers.edu            
            Chemicals/CAS: oxoglutarate dehydrogenase, 9031-02-1; Ketoglutarate Dehydrogenase Complex; Reactive Oxygen Species            
            Funding details: National Science Foundation, NSF, CHE-1402675            
            Funding details: National Institutes of Health, NIH, R15GM116077-01            
            Funding details: Semmelweis Egyetem, STIA-OTKA-2021            
            Funding details: Hungarian Scientific Research Fund, OTKA, 143627            
            Funding details: Nemzeti Kutatási, Fejlesztési és Innovaciós Alap, NKFIA, TKP2021-EGA-25            
            Funding text 1: This research was funded by the National Institutes of Health (R15GM116077-01 to F.J.), the National Science Foundation (CHE-1402675 to F.J.), Rutgers–Newark Chancellor’s SEED Grants (F.J.), the Hungarian Brain Research Program 2 (2017-1.2.1-NKP-2017-00002 to Vera Adam-Vizi, Semmelweis University), Semmelweis University (STIA-OTKA-2021 grant to A.A.), the Hungarian Scientific Research Fund (OTKA grant 143627 to A.A.), and the National Research, Development and Innovation Fund (TKP2021-EGA-25 grant to A.A.). Project no. TKP2021-EGA-25 has been implemented with the support provided by the Ministry of Innovation and Technology of Hungary from the National Research, Development and Innovation Fund, financed under the TKP2021-EGA funding scheme.
AB  - The human 2-oxoglutarate dehydrogenase complex (hOGDHc) is a key enzyme in the tricarboxylic acid cycle and is one of the main regulators of mitochondrial metabolism through NADH and reactive oxygen species levels. Evidence was obtained for formation of a hybrid complex between the hOGDHc and its homologue the 2-oxoadipate dehydrogenase complex (hOADHc) in the L-lysine metabolic pathway, suggesting a crosstalk between the two distinct pathways. Findings raised fundamental questions about the assembly of hE1a (2-oxoadipate-dependent E1 component) and hE1o (2-oxoglutarate-dependent E1) to the common hE2o core component. Here we report chemical cross-linking mass spectrometry (CL-MS) and molecular dynamics (MD) simulation analyses to understand assembly in binary subcomplexes. The CL-MS studies revealed the most prominent loci for hE1o-hE2o and hE1a-hE2o interactions and suggested different binding modes. The MD simulation studies led to the following conclusions: (i) The N-terminal regions in E1s are shielded by, but do not interact directly with hE2o. (ii) The hE2o linker region exhibits the highest number of H-bonds with the N-terminus and α/β1 helix of hE1o, yet with the interdomain linker and α/β1 helix of hE1a. (iii) The C-termini are involved in dynamic interactions in complexes, suggesting the presence of at least two conformations in solution.
LA  - English
DB  - MTMT
ER  - 

TY  - JOUR
AU  - Piroli, Gerardo
AU  - McCain, Richard
AU  - Manuel, Allison
AU  - Swaminathan, Shoba
AU  - Smith, Holland
AU  - Ozohanics, Olivér
AU  - Cotham, William
AU  - Walla, Michael
AU  - Ambrus, Attila
AU  - Frizzell, Norma
TI  - Succination of Dihydrolipoyllysine Succinyltransferase by Fumarate Reduces α-Ketoglutarate Dehydrogenase Activity and Exacerbates Mitochondrial ATP Deficits in the Ndufs4 Knockout Model of Leigh Syndrome
JF  - FREE RADICAL BIOLOGY AND MEDICINE
J2  - FREE RADICAL BIO MED
VL  - 180
PY  - 2022
IS  - S1
SP  - 105
EP  - 106
PG  - 2
SN  - 0891-5849
DO  - 10.1016/j.freeradbiomed.2021.12.245
UR  - https://m2.mtmt.hu/api/publication/33081592
ID  - 33081592
LA  - English
DB  - MTMT
ER  - 

TY  - JOUR
AU  - Horváth, Gergő
AU  - Sváb, Gergely
AU  - Komlódi, Tímea
AU  - Ravasz, Dóra
AU  - Kacsó, Gergely
AU  - Dóczi, Judit
AU  - Chinopoulos, Christos
AU  - Ambrus, Attila
AU  - Tretter, László
TI  - Reverse and Forward Electron Flow-Induced H2O2 Formation Is Decreased in α-Ketoglutarate Dehydrogenase (α-KGDH) Subunit (E2 or E3) Heterozygote Knock Out Animals
JF  - ANTIOXIDANTS
J2  - ANTIOXIDANTS-BASEL
VL  - 11
PY  - 2022
IS  - 8
PG  - 19
SN  - 2076-3921
DO  - 10.3390/antiox11081487
UR  - https://m2.mtmt.hu/api/publication/33070137
ID  - 33070137
N1  - Cited By :1            
            Export Date: 7 October 2022            
            Correspondence Address: Tretter, L.; Department of Biochemistry, Hungary; email: tretter.laszlo@med.semmelweis-univ.hu            
            Funding details: Semmelweis Egyetem, STIA-OTKA-2021, TKP2021-EGA-25            
            Funding details: Nemzeti Kutatási, Fejlesztési és Innovaciós Alap, NKFIA, EFOP-3.6.3-VEKOP-16-2017-00009            
            Funding text 1: This research was funded by the Hungarian Brain Research Program 2 (2017-1.2.1-NKP-2017-00002 to Vera Adam-Vizi, Semmelweis University), STIA-OTKA-2021 grant (from the Semmelweis University, to A.A.), TKP2021-EGA-25 grant to A.A. and C.C., Project no. TKP2021-EGA-25 has been implemented with the support provided by the Ministry of Innovation and Technology of Hungary from the National Research, Development and Innovation Fund, financed under the TKP2021-EGA funding scheme. EFOP-3.6.3-VEKOP-16-2017-00009 support to G.S.
AB  - α-ketoglutarate dehydrogenase complex (KGDHc), or 2-oxoglutarate dehydrogenase complex (OGDHc) is a rate-limiting enzyme in the tricarboxylic acid cycle, that has been identified in neurodegenerative diseases such as in Alzheimer’s disease. The aim of the present study was to establish the role of the KGDHc and its subunits in the bioenergetics and reactive oxygen species (ROS) homeostasis of brain mitochondria. To study the bioenergetic profile of KGDHc, genetically modified mouse strains were used having a heterozygous knock out (KO) either in the dihydrolipoyl succinyltransferase (DLST+/−) or in the dihydrolipoyl dehydrogenase (DLD+/−) subunit. Mitochondrial oxygen consumption, hydrogen peroxide (H2O2) production, and expression of antioxidant enzymes were measured in isolated mouse brain mitochondria. Here, we demonstrate that the ADP-stimulated respiration of mitochondria was partially arrested in the transgenic animals when utilizing α-ketoglutarate (α-KG or 2-OG) as a fuel substrate. Succinate and α-glycerophosphate (α-GP), however, did not show this effect. The H2O2 production in mitochondria energized with α-KG was decreased after inhibiting the adenine nucleotide translocase and Complex I (CI) in the transgenic strains compared to the controls. Similarly, the reverse electron transfer (RET)-evoked H2O2 formation supported by succinate or α-GP were inhibited in mitochondria isolated from the transgenic animals. The decrease of RET-evoked ROS production by DLST+/− or DLD+/− KO-s puts the emphasis of the KGDHc in the pathomechanism of ischemia-reperfusion evoked oxidative stress. Supporting this notion, expression of the antioxidant enzyme glutathione peroxidase was also decreased in the KGDHc transgenic animals suggesting the attenuation of ROS-producing characteristics of KGDHc. These findings confirm the contribution of the KGDHc to the mitochondrial ROS production and in the pathomechanism of ischemia-reperfusion injury.
LA  - English
DB  - MTMT
ER  - 

TY  - JOUR
AU  - Nemeria, Natalia S.
AU  - Nagy, Bálint
AU  - Sanchez, Roberto
AU  - Zhang, Xu
AU  - Leandro, Joao
AU  - Ambrus, Attila
AU  - Houten, Sander M.
AU  - Jordan, Frank
TI  - Functional Versatility of the Human 2-Oxoadipate Dehydrogenase in the L-Lysine Degradation Pathway toward Its Non-Cognate Substrate 2-Oxopimelic Acid
JF  - INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
J2  - INT J MOL SCI
VL  - 23
PY  - 2022
IS  - 15
PG  - 20
SN  - 1661-6596
DO  - 10.3390/ijms23158213
UR  - https://m2.mtmt.hu/api/publication/33065332
ID  - 33065332
N1  - Department of Chemistry, Rutgers University-Newark, Newark, NJ 07102-1811, United States            
            Department of Biochemistry, Institute of Biochemistry and Molecular Biology, Semmelweis University, Budapest, 1082, Hungary            
            Icahn Institute for Data Science and Genomic Technology, Icahn School of Medicine at Mount Sinai, New York, NY 10029-6501, United States            
            Export Date: 7 October 2022            
            Correspondence Address: Nemeria, N.S.; Department of Chemistry, United States; email: nemeria@newark.rutgers.edu            
            Correspondence Address: Jordan, F.; Department of Chemistry, United States; email: frjordan@newark.rutgers.edu            
            Funding details: National Institutes of Health, NIH, GM050380, R15-GM116077            
            Funding details: Eunice Kennedy Shriver National Institute of Child Health and Human Development, NICHD, R03HD092878, R21HD088775            
            Funding details: Semmelweis Egyetem, STIA-OTKA-2021, TKP2021-EGA-25            
            Funding details: Nemzeti Kutatási, Fejlesztési és Innovaciós Alap, NKFIA            
            Funding text 1: Research reported in this publication was supported by the National Institutes of Health (grants GM050380 and R15-GM116077 to F.J.); Hungarian Brain Research Program 2 (2017-1.2.1-NKP-2017-00002 to Vera Adam-Vizi, Semmelweis University), STIA-OTKA-2021 grant (from the Semmelweis University, to A.A.) and TKP2021-EGA-25 grant to A.A. Project no. TKP2021-EGA-25 has been implemented with the support provided by the Ministry of Innovation and Technology of Hungary from the National Research, Development and Innovation Fund, financed under the TKP2021-EGA funding scheme; Eunice Kennedy Shriver National Institute of Child Health &Human Development of the National Institutes of Health (R03HD092878 and R21HD088775 to S.M.H).
AB  - The human 2-oxoadipate dehydrogenase complex (OADHc) in L-lysine catabolism is involved in the oxidative decarboxylation of 2-oxoadipate (OA) to glutaryl-CoA and NADH (+H+). Genetic findings have linked the DHTKD1 encoding 2-oxoadipate dehydrogenase (E1a), the first component of the OADHc, to pathogenesis of AMOXAD, eosinophilic esophagitis (EoE), and several neurodegenerative diseases. A multipronged approach, including circular dichroism spectroscopy, Fourier Transform Mass Spectrometry, and computational approaches, was applied to provide novel insight into the mechanism and functional versatility of the OADHc. The results demonstrate that E1a oxidizes a non-cognate substrate 2-oxopimelate (OP) as well as OA through the decarboxylation step, but the OADHc was 100-times less effective in reactions producing adipoyl-CoA and NADH from the dihydrolipoamide succinyltransferase (E2o) and dihydrolipoamide dehydrogenase (E3). The results revealed that the E2o is capable of producing succinyl-CoA, glutaryl-CoA, and adipoyl-CoA. The important conclusions are the identification of: (i) the functional promiscuity of E1a and (ii) the ability of the E2o to form acyl-CoA products derived from homologous 2-oxo acids with five, six, and even seven carbon atoms. The findings add to our understanding of both the OADHc function in the L-lysine degradative pathway and of the molecular mechanisms leading to the pathogenesis associated with DHTKD1 variants.
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  - 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  -