Heterologous expression and in vitro assembly of the transmembrane cytochrome b6.
Folding and assembly studies with alpha-helical membrane proteins are often hampered by the absence of high-level expression systems as well as by missing suitable in vitro refolding procedures. Experimental constraints and requirements for heterologous expression and in vitro assembly of cytochrome b6 have been examined and conditions for in vitro reconstitutions of the protein have been optimized. Cytochrome b6 can serve as an excellent model system for in vitro studies on the dynamic interplay of an apo-protein and heme cofactors during assembly of a transmembrane b-type cytochrome. In vitro assembled cytochrome b6 binds two hemes with different midpoint potentials and both ferri as well as ferro heme bind to the apo-cytochrome. However, the ferro cytochrome appears to be less stable than the ferri form.
Prodöhl
Alexander
A
Institut für Biochemie und Molekularbiologie, Zentrum für Biochemie und Molekulare Zellforschung, Albert-Ludwigs-Universität Freiburg, Stefan-Meier-Strasse 19, 79104 Freiburg, Germany.
Dreher
Carolin
C
Hielscher
Ruth
R
Hellwig
Petra
P
Schneider
Dirk
D
D045347:Cytochromes b6 / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D010084:Oxidation-Reduction; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D017510:Protein Folding
D045347:Cytochromes b6; D008565:Membrane Proteins; D010940:Plant Proteins