Copro, proto-porphyrin

In the normal human the excretion of porphyrins in the urine per day (Table X) may amount to 100 /tg of which COPRO-I isomer is the main component lesser amounts of COPRO-III and only traces of URO are excreted (SffO). In the feces about 0.5 mg of a mixture of COPRO, PROTO, and deuteroporphyrin are excreted per day. The traces of deuteroporphyiin (Fig. 1) are assumed to be formed by the action of the intestinal bacteria on the excreted porphyrins and heme fecal porphsrrin is due miunly to syntheffls by intestinal flora as well as to chlorophyll derivatives (e.g. phylloerythrin) from ingested vegetable material (4). 

Table 1 provides a fairly comprehensive listing of trivial names still in regular use in the porphyrin and chlorophyll area. The uro-, copro- and etio-porphyrins are examples of primary type isomer systems, while proto-, meso-, deutero- and hemato-porphyrins derive from the situation where 15 isomers exist. Phyllo-, pyrro- and rhodo-porphyrins, all being chlorophyll degradation products, are examples of the situation where there are four different kinds of porphyrin substituent. It transpires that, in biologically important porphyrin derivatives, the isomer chosen by Nature is Type-Ill (for the primary system), Type-IX (with three types of substituent) and Type-XV (with four). As can be seen in Schemes 1 and 2, primary type-III is related to type-IX in Scheme 2, and type-IX is in turn related to type-XV in the yet more complicated four-substituent system. 

VP PBG > ALA Copro III, uroporphyrin from PBG Proto IX > Copro III, X-porphyrin Not increased 624-628 nm... 

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