Promoted evolution of a shortened variant of heme A synthase in the membrane of Bacillus subtilis.
Bacillus subtilis heme A synthase is a membrane protein with 8 transmembrane segments. By using a two-step mutagenesis approach we have generated and selected a fully functional enzyme protein variant with a seven residue internal deletion. The biochemical properties of the shortened variant are similar to those of the normal enzyme. This could indicate that residue H209 in the mutant protein substitutes for the missing H216 as an axial ligand to the heme iron. Our results provide insight in routes of membrane protein evolution and the structure of heme A synthases.
Lewin
Anna
A
Department of Cell and Organism Biology, Lund University, Sölvegatan 35, SE 22362 Lund, Sweden.
Hederstedt
Lars
L
D000595:Amino Acid Sequence; D001412:Bacillus subtilis / Q000201:enzymology* / Q000235:genetics; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D005075:Biological Evolution; D002462:Cell Membrane / Q000201:enzymology; D003573:Cytochrome b Group / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017931:DNA Primers; D004591:Electrophoresis, Polyacrylamide Gel; D017353:Gene Deletion; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data
D001426:Bacterial Proteins; C090098:CtaA protein, bacteria; D003573:Cytochrome b Group; D017931:DNA Primers; D008565:Membrane Proteins