Centered Radicals in Enzyme Reactions

Free radicals provide the only feasible means of aetivating eertain key C6C, C60 or C6N bonds in otherwise inert substrate moleeules this is aehieved by abstraction of a hydrogen atom from an unactivated carbon (Frey, 1990). The resulting unpaired electron leaves the earbon atom highly reaetive and amenable to various further reaetions. In the ease of AdoCbl, 

Corrinoid-dependent enzymes for which the cofactor-binding mode is known. Data compiied from A. Padmakumar et al, 1995 Mancia et al., 1996. B. Zelder et al, 1995 Reitzer et al., 1999. C. Drennan et al., 1994a. D. Sauer and Thauer, 1998b. E. Sauer and Thauer, 1998a. F. Abend et al., 1998 Yamanishi et al., 1998. G. Lawrence et al., 1999. H. Ragsdale et al., 1987 Jablonski et al, 1993 Grahame 

DxHxxG -methyl-H4-methanopterin Diol dehydrase Corrinoid/Fe-S 

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