A vital characteristic of living systems is their ability to produce biological energy (ATP) efficiently. ATP is essential for cellular functions including biosynthesis, transport, signal transduction, chemo- and photo-taxis and thermogenesis. Energy producing complexes are widespread among organisms, and their improper function leads to devastating health problems and human diseases and low crop yields in plants. The long-term goal of this project is to understand the structure, mechanism of function and biogenesis of cytochrome (cyt) components of energy pathways. Bacteria provide excellent model systems for these studies that are pertinent to eukaryotic organelles. This project will use molecular genetics, proteomics, biochemical and biophysical approaches, with a sharp focus on the critical links between the structure-function and the biogenesis of the membrane-bound cyt bc1. This is a crucial enzyme whose absence or malfunction is the cause of multiple human diseases, including many muscular and neurological disorders. Resolution of the 3D structure of the cyt bc1 revealed the mobility of its FeS protein subunit, and is now leading to a chemical description of its mechanism of function, while our understanding of its biogenesis remains rudimentary even in simpler bacteria.
The specific aims i nclude probing the control mechanisms of the FeS protein motion to avoid unwanted side reactions, creating novel bc1 complex variants to visualize the internal reaction steps that are difficult to monitor, and characterizing novel biogenesis components of energy transducing cyt c complexes, including incorporation of their prosthetic groups. These studies will greatly enhance our understanding and knowledge of the structure, mechanism of function and biogenesis of the cyt bc1 as a prototype enzyme. Insights gained using this simpler system are generally applicable to the structurally more complex and yet functionally similar organelle-derived complexes, and could provide guiding lights for elucidating the molecular bases of mitochondrial and other human diseases and aging.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM038237-21
Application #
7238632
Study Section
Physical Biochemistry Study Section (PB)
Program Officer
Ikeda, Richard A
Project Start
1987-12-01
Project End
2009-05-31
Budget Start
2007-06-01
Budget End
2008-05-31
Support Year
21
Fiscal Year
2007
Total Cost
$319,360
Indirect Cost
Name
University of Pennsylvania
Department
Biology
Type
Schools of Arts and Sciences
DUNS #
042250712
City
Philadelphia
State
PA
Country
United States
Zip Code
19104
Khalfaoui-Hassani, Bahia; Wu, Hongjiang; Blaby-Haas, Crysten E et al. (2018) Widespread Distribution and Functional Specificity of the Copper Importer CcoA: Distinct Cu Uptake Routes for Bacterial Cytochrome c Oxidases. MBio 9:
Trasnea, Petru-Iulian; Andrei, Andreea; Marckmann, Dorian et al. (2018) A Copper Relay System Involving Two Periplasmic Chaperones Drives cbb3-Type Cytochrome c Oxidase Biogenesis in Rhodobacter capsulatus. ACS Chem Biol 13:1388-1397
Sandri, Federica; Musiani, Francesco; Selamoglu, Nur et al. (2018) Pseudomonas pseudoalcaligenes KF707 grown with biphenyl expresses a cytochrome caa3 oxidase that uses cytochrome c4 as electron donor. FEBS Lett 592:901-915
Tropeano, Concetta Valentina; Fiori, Jessica; Carelli, Valerio et al. (2018) Complex II phosphorylation is triggered by unbalanced redox homeostasis in cells lacking complex III. Biochim Biophys Acta Bioenerg 1859:182-190
Vos, Marten H; Reeder, Brandon J; Daldal, Fevzi et al. (2017) Correction: Ultrafast photochemistry of the bc1 complex. Phys Chem Chem Phys 19:9320
Foley, Shawn W; Gosai, Sager J; Wang, Dongxue et al. (2017) A Global View of RNA-Protein Interactions Identifies Post-transcriptional Regulators of Root Hair Cell Fate. Dev Cell 41:204-220.e5
Vos, Marten H; Reeder, Brandon J; Daldal, Fevzi et al. (2017) Ultrafast photochemistry of the bc1complex. Phys Chem Chem Phys 19:6807-6813
Onder, Ozlem; Verissimo, Andreia F; Khalfaoui-Hassani, Bahia et al. (2017) Absence of Thiol-Disulfide Oxidoreductase DsbA Impairs cbb3-Type Cytochrome c Oxidase Biogenesis in Rhodobacter capsulatus. Front Microbiol 8:2576
Verissimo, Andreia F; Khalfaoui-Hassani, Bahia; Hwang, Josephine et al. (2017) The thioreduction component CcmG confers efficiency and the heme ligation component CcmH ensures stereo-specificity during cytochrome c maturation. J Biol Chem 292:13154-13167
Trasnea, Petru-Iulian; Utz, Marcel; Khalfaoui-Hassani, Bahia et al. (2016) Cooperation between two periplasmic copper chaperones is required for full activity of the cbb3 -type cytochrome c oxidase and copper homeostasis in Rhodobacter capsulatus. Mol Microbiol 100:345-61

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