The biochemistry of iron

It is impossible to cover adequately the chemistry of various elements in biological systems in a single chapter. Before discussing the salient points of other essential and trace elements, Ihe biochemistry of iron will be discussed briefly. Iron is the most 

Note added in proof The slraciure of Ihe Fe-Mo cofactor died in Footnote 97 has led those authors to suggest that the molybdenum docs not directly participate in binding Ihe dinilrogen molecule. The Mo is already six-coordinate with three S atoms, two O uioms from a hamocitnuc anion, and one N atom from a histidine in the protein chain. Therefore, in Eq. 19.38 the N, is probably bound to an Fc—S duster in place of Mo. 

100 Crichton, R. R. Inorganic Biochemistry of Iron Metabolism Ellis Horwood New York, 1991. 

102 Sugiura. Y. Nomoto, K. Struct. Bonding (BerlinJ t984. 58. 107. 

The presence of organic chelates of iron in surface waters has been related to the red tide. an explosive Hoorn of algae (Gymnodium breve) that results in mass mortality of fish. It is possible to correlate the occurrence of these outbreaks with the volume of stream flow and the concentrations of iron and humic acid.1 3 At least one of the dinoflagellates in the red tide possesses an iron-binding siderophone (see below), to  

CrkMon, R. R. laorgaidc Kothemairjtiflmn MetaboSan-, Elis Horwood New Ymk. 1991. 

The question of iron chelation as an antibacterial defense is receiving increasing attention. It appeals lo be far more general than had previously been supposed. o An interesting sidelight is that the fever that often accompanies infection enhances the bacteriostatic action of the body s liansferrins. 

An interesting side effect of the pre.sence of ovatransfeirin in egg whites b the custom, long established before any rational explanation, of beating egg whiles in copper bowls lo stabilize the foam (as in meringues, etc) The copper complex of ovalransferrin stabilizes the protein of egg white against denaluralion and thus stabilizes the foam.  

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General reference W. Schneider, Iron Hydrolysis and the Biochemistry of Iron -The Interplay of Hydroxide and Biogenic Ligands, Chimia 42, 9-20 (1988). 

The biochemistry of iron has just been discussed in some detail including the biochemical species involved, bioaccumulation, transport, storage, and toxicity- Space does not permit an extensive discussion of other elements of importance. However, a brief discussion will be presented here with a table summarizing what is currently known. 

THE BIOCHEMISTRY OF IRON —A SURVEY OF IRON-CONTAINING ACTIVE SITES 614... 

Nature uses many different t5rpes of metalloproteins for the binding, transportation, and controlled activation of oxygen (10,13). An extremely versatile catalyst system is present in the biochemistry of iron-containing heme enz5unes (Fig. 21). 

Schneider, W. Iron hydrolysis and the biochemistry of iron The interplay of hydroxide and biogenic ligands. Chimia 42 (1988), 9-20. 

In order to accommodate new material, several changes have been made. The first four chapters have been modified so as to eliminate the more elementary aspects of atomic structure and give more coverage of symmetry and molecular structure. Various rearrangements of chapters and of material within sections have been made. One new chapter, on selected aspects of homogeneous catalysis by transition metal organometallic compounds has been added while some information on the biochemistry of iron, copper, cobalt, zinc and molybdenum is now provided. 

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