285 As this enzyme subfamily is involved in the biosynthesis of several important thiopeptides and antibiotics, advances are likely to be significant in differentiating the role that the cobalamin serves in Class B methyltransferases to the role served by the HemN-like domain.
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The sentences
2 Four years later the same group reported the primary structures of PFL and PFL-AE, and noted “a cluster of three cysteines...which may be significant for the putative Fe-binding and redox-functional properties of this enzyme.” 61 This cysteine “cluster” was, of course, the canonical radical SAM superfamily CX 3 CX 2 C motif.