Coq7p relevant residues for protein activity and stability

Author(s)

Busso, Cleverson ^{[1, 2]} ; Ferreira-Junior, Jose Ribamar ^[3] ; Paulela, Janaina A. ^[1] ; Bleicher, Lucas ^[4] ; Demasi, Marilene ^[5] ; Barros, Mario H. ^[1]

Affiliation

^[1] Univ Sao Paulo, Dept Microbiol, Inst Ciencias Biomed, BR-05508900 Sao Paulo - Brazil

^[2] Univ Tecnol Fed Parana UTFPR, COBIO, Dois Vizinhos, Parana - Brazil

^[3] Univ Sao Paulo, Escola Artes Ciencias & Humanidades, BR-05508900 Sao Paulo - Brazil

^[4] Univ Fed Minas Gerais, Inst Ciencias Biol, Dept Bioquim & Imunol, Belo Horizonte, MG - Brazil

^[5] Inst Butantan, Lab Bioquim & Biofis, Sao Paulo - Brazil

• Document type: Journal article
• Source: Biochimie; v. 119, p. 92-102, DEC 2015.
• Web of Science Citations: 8

Abstract

Coenzyme Q (Q) is an isoprenylated benzoquinone electron carrier required for electronic transport in the mitochondrial respiratory chain, shuttling electrons from complexes I and II to complex III. Q synthesis requires proteins termed Coq (Coq1-Coq11). Coq7p is part of the multimeric complex involved in Q synthesis catalyzing the hydroxylation of demethoxy-Q(6) (DMQ(6)), the last monooxygenase step in Q synthesis with a catalytic center containing a carboxylate-bridged di-iron at the active site of the enzyme. Here we indicate a group of Coq7p residues that modulate protein activity: D53, R57, V111 and S114. R57, V111 and S114 are very conserved residues; V111 and S114 are present in separated communities of amino acid correlation analysis. The coq7 double mutant V111G/S114A and S114E show respiratory deficiency at non permissive temperature, DMQ(6) accumulation and lower content of Q. Therefore we conclude that phosphomimetic S114E inhibit Coq7p activity, and propose that S114 phosphorylation is required to move a non-structured loop of 25 amino acids between helix 2 and 3, and that affects the di-iron coordination in Coq7p catalytic center. (C) 2015 Elsevier B.V. and Societe Francaise de Biochimie et Biologie Moleculaire (SFBBM). All rights reserved. (AU)

• FAPESP's process: 11/07366-5 - Study of mitochondrial proteins of unknown function and their respective effects on cell viability
• Grantee: Mario Henrique de Barros
• Support Opportunities: Regular Research Grants
• FAPESP's process: 13/07937-8 - Redoxome - Redox Processes in Biomedicine
• Grantee: Ohara Augusto
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC