[Expression of mutant horse cytochrome c genes in Escherichia coli]

Here we describe genetically engineered constructs for the expression in Escherichia coli of genes for horse cytochrome c mutants. These constructs allow the expression of the cytochrome c genes together with hemeligase, an enzyme which covalently links heme to cytochrome. Careful selection of producer strains and the adjustment of the conditions of expression provided for expression levels of 10-15 mg of protein per liter of culture. This is by an order of magnitude greater than the expression previously achieved in yeast. A series of horse cytochrome c mutants were obtained in this way.