Functional ironcontaining proteins

Haemoglobin (molecular weight = 64 500) contains four haem groups linked to four globin chains, and can bind four molecules of oxygen. Myoglobin (mol. wt = 17 000) accounts for 4-5% of body iron and has a single haem group attached to its one polypeptide chain. It has a higher affinity for oxygen than haemoglobin and behaves as an oxygen reserve in muscles. The mitochondria contain a series of haem and non-haem iron proteins (including the cytochromes a, b and c, succinate dehy-drogenase and cytochrome oxidase) that form an electron transport pathway responsible for the oxidation of intracellular

Iron-donating tissues and iron stores Macrophages 500 mg Hepatocytes 250 mg

RE stores

Ineffective erythropoiesis

Iron-donating tissues and iron stores Macrophages 500 mg Hepatocytes 250 mg

RE stores

Absorption 1 mg/day

O Plasma (transferrin) 4 mg

Loss 1 mg/day

Absorption 1 mg/day

O Plasma (transferrin) 4 mg

Loss 1 mg/day

Red cell haemoglobin 2500 mg

Bone marrow

Tissues

Erythroblasts 150 mg

Iron-containing enzymes 150 mg Myoglobin 300 mg

Iron receptor tissues and functional iron compounds

Figure 3.1 The major compartments of iron in a 70-kg man. Iron supply for erythropoiesis and release of iron from senescent red cells dominate internal iron exchange.

substrates and the simultaneous production of adenosine triphosphate. Haem is an essential component of microsomal and mitochondrial cytochrome P450, which is concerned with hydroxylation reactions (including drug detoxification by the liver), and of cyclo-oxygenase, involved in prostaglandin synthesis. Other haem proteins include the enzymes catalase and lactoperoxidase, which are concerned with peroxide breakdown, and tryptophan pyrrolase, involved in the oxidation of tryptophan to formylkynurenine. There is a smaller group of iron sulphur proteins (e.g. xanthine oxidase, reduced nicotinamide adenine dinucleotide dehydrogenase and aconitase). Iron is also necessary for the function of ribonucleotide reduc-tase, a key enzyme in DNA synthesis.

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Detoxification and Weight Loss

Detoxification and Weight Loss

Detoxification is something that is very important to the body, but it is something that isn't understood well. Centuries ago, health masters in the East understood the importance of balancing and detoxifying the body. It's something that Western medicine is only beginning to understand.

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