Formation of sulphmyoglobin during expression of horse heart myoglobin in Escherichia coli

AbstractExpression of recombinant horse heart myoglobin in Escherichia coli has been found to result in the production of both native and variable amounts (~ 16–17% total) of two sulphmyoglobin isomers. The recombinant sulphmyoglobin produced consists primarily of the A and B isomers as identified by 1H NMR spectroscopy with no evidence for production of the C isomer. Conversion of recombinant sulphmyoglobin to the native protein can be achieved by reconstitution with protohaem IX. The possible relationship of this observation to recombinant expression of other heme proteins is discussed