Porphyrin production

Attempts to exploit the reaction of the dianion with alkyl halides to produce a c/.v-dialkyl complex by using 1,2- or 1,3-dihaloalkanes did not indeed give this result. The reaction of Ru(Por) " with 1,2-dibromoethane was sucessful, but the resulting metallacyclopropane product is better formulated as a /r-complex of ethene, and will be discussed below in the section on alkenc and alkyne complexes. The corresponding reaction of the diiinion with 1,3-dichloropropane gave no evidence for a metallacyclobutane. but instead free cyclopropane was detected by GC analysis and the porphyrin product was Ru(TTP)(THF)2. ... 

Radiolytic reduction has been investigated as a means of producing transient Rh(II) porphyrin products, and as in the above study, the observed products were strongly dependent on pH and solvent. Radiolytic reduction of Rh(TMP)Cl in alcohol formed transient Rh(TMP)- which was prevented from dimerization by the bulky TMP ligand. In alkaline 2-propanol the product is [Rh(TMP)r. in weakly acidic 2-propanol the hydride Rh(TMP)H is formed, and in strongly acidic 2-propanol the alkylated rhodium(III) porphyrins Rh(TMP)CH3 and Rh(TMP) (C(CH 3)20H) are observed. The alkyl products result from reaction of Rh(TMP)-with CH3- and C(CH3)20H formed by radiolysis of the 2-propanol solvent. 

HeyerNJ, Bittner Jr AC, Echeverria D, Woods JS. 2006. A cascade analysis of the interaction of mercury and coproporphyrinogen oxidase (CPOX) polymorphism on the heme biosynthetic pathway and porphyrin production. Toxicol Lett 161 159-166. 

The above account of selectivity of inorganic plus organic chemistry in synthesis is given rather extensively to stress three points. All the four (Mg, Fe, Co and Ni) porphyrin products came from one source, the synthesis of uroporphyrin. The basis of selection is very different from that in primitive centres which use thermodynamic stability constant selectivity based on different donor atoms for different metal ions. Here, all ion complexes have the same donor atoms, nitrogen, the most constrained being the coordination of Mg2+ by five nitrogens exactly as is seen for Fe in haemoglobin. Hence, there also has to be a new control feedback to ensure that the appropriate quantities of each metal cofactor is produced in a balanced way, that is synthesis from uroporphyrin has to be divided based upon... 

TPP)Rh(L)J+C1 in the presence of an alkyl halide leads to a given (P)Rh(R) or (P)Rh(RX) complex. The yield was nearly quantitative (>80X) in most cases based on the rhodium porphyrin starting species. However, it should be noted that excess alkyl halide was used in Equation 3 in order to suppress the competing dimerization reaction shown in Equation 1. The ultimate (P)Rh(R) products generated by electrosynthesis were also characterized by H l MR, which demonstrated the formation of only one porphyrin product(lA). No reaction is observed between (P)Rh and aryl halides but this is expected from chemical reactivity studles(10,15). Table I also presents electronic absorption spectra and the reduction and oxidation potentials of the electrogenerated (P)Rh(R) complexes. 

Lee WLS, Shalita AR and Poh-Fitzpatrick MB (1978) Comparative studies of porphyrin production in Propionibacterium acnes and Propionibacterium granulo-sum. J Bacteriol 133, 811-815. 

Hb and Ni-reconstituted Hb were prepared according to reported methods (13). Mb was made by the method of Alston and Storm (14) Solutions of the proteins in 0.05 M phosphate buffer at pH 7.5 were used for obtaining spectra. The proteins are stable in air and do not photodecompose. Ni protoporphyrin IX (Ni(ProtoP)), Ni uroporphyrin I (Ni(UroP)), and Ni octaethylporphyrin (Ni(OEP)) were obtained from Porphyrin Products and used without further purification. All solvents were of highest purity obtainable from commercial sources. All materials showed the literature uv-visible absorption spectra. Absorption spectra were obtained on a Perkin-Elmer Model 330 spectrophotometer. 

All Ni(OEP) and Ni(PP) samples (obtained from Porphyrin Products) were prepared (0.2-0.5 mM) in neat, spectral grade solvent (used without further purification) and were deoxygenated by purging with oxygen-free N2 S s. No differences in the spectra were noted for aerobic and anaerobic samples. 

Another major problem associated with the extraction of DNA from archaeological specimens is that the procedure often co-extracts impurities that can later complicate, or prevent, the study of the extracted DNA by inhibiting PCR amplification (reviewed by 5). Commonly encountered inhibitory substances found in aDNA extracted from teeth, bones, mummified tissue, and coprolites include humic acids, ftilvic acids, tannins, porphyrin products, phenolic compounds, hematin, and collagen type I (37—42). The formation of Maillard products, commonly encountered in coprolite samples, can also prevent PCR amplification by causing DNA to become inaccessibly trapped in these sugar-derived condensation products (12). As the negative results in many aDNA studies are attributed to the presence of PCR inhibitors, our extraction method outlined below pays particular attention to the problem and offers a simple test for the presence of PCR inhibitors in DNA extracts. 

Treatment of TPPFe(III)Cl or raeso-tetra-o-tolylporphinato-iron(III) chloride [TTPFe(III)Cl (10)] with iodosylbenzene caused rapid oxidation of the porphyrin and loss of catalytic activity for hydrocarbon oxidation. Figure 1 shows changes in the visible absorption spectrum upon treatment of 10 with iodosylbenzene. These data indicate that shortly after the addition of iodosylbenzene (Scan b, Figure 1) a new porphyrin species (11) is formed, which then rapidly decays to oxidized porphyrin products. The kinetics of this decay process are approximately first order (Figure 2). 

The general properties of siderophores have been described extensively (2), and up-to-date lists of the individual compounds, their sources from aerobic and facultative aerobic species, and their properties have been published (3,4, 5). (Porphyrin Products, P. O. Box 31, Logan, UT 84321, sell a limited number of siderophores.) The earlier literature on iron assimilation by microbes, including enteric species, may be found elsewhere (6,7). For information on the chemical constitution and physiological role of the outer membrane of enteric bacteria, the reader is referred to Nakae and Nikaido (8). 

Protoporphyrin IX dimethyl ester may be purchased (e.g., Porphyrin Products, Sigma, Strem) or prepared according to literature procedures.1 A convenient... 

The mechanism of cholestasis from cyclosporine may result due to interference with uptake and transport of bile salts. Cyclosporine also causes prerenal vasoconstriction and decreased glomerular perfusion, which is sometimes dose-dependent. Cyclosporine induces enzymes in porphyrin production, which can exacerbate the symptoms of porphyria. 

Hift R, Meissner P. Miscellaneous abnormalities in porphyrin production and disposal. In Kadish KM, Smith KM, Guilard R, eds. The porphyrin handbook, vol. 14, Medical aspects of porphyrias. Amsterdam Academic Press, 2003 151-68. 

As standard the Porphyrin acids chromatographic marker kit is used (Porphyrin products, INC., CMK-IA). 

The following standards are used Uroporphyrin fluorescence standard. Uroporphyrin I (Porphyrin products, INC. UFS-I), Uropwrphyrin III octamethyl ester (Sigma), Coproporphyrin I (Sigma), Coproporphyiin fluorescence standard. Coproporphyrin III... 

The standards used were Coproporphyrin fluorescente Standard (Porphyrin products, INC. CFS-3, Logan, UTA, USA), Protoporphyrin fluorescent Standard (Porphyrin products, INC. PFS-9, Logan, UTA, USA) and Mesoporphyiin IX (Porphyrin products, INC. M 566-9, Logan, UTA, USA). 

Protoporphyrinogen III oxidase (EC 1.3.3.4). Ferro-chelatase activity may also be decreased. Impaired feedback inhibition of 5-aminolevulinate synthase results in excessive porphyrin production. Increased urinary porphobilinogen, 5-aminolevulinate, protoporphyrin and coproporphyrin during acute attacks. Fecal protoporphyrin and coproporphyrin constantly elevated. Fecal porphyrin-peptide conjugates increased. Mild photodermatoses clinical picture otherwise similar to that of acute intermittent porphyria. Treatment as for latter. Rare, except in white South Africans, where frequency is 0.4%. Autosomal dominant. 

The compounds with X = OMe were relatively stable after reduction, but the compounds with X = CP were shown to undergo a series of chemical reactions following electron transfer. The ultimate stable porphyrin product of the reduction was proposed to contain a Sb(III) ion. The electroreduction mechanism of [(P)Sb(X)2]+ is illustrated in Sch. 14. 

One of the most active inducing compounds is Lindane. It is about 100 times as active as AIA in porphyrin induction in chick embyro liver culture as well as in the increase in ALA-synthetase activity [21]. The relative activities of isomers of hexahydrohexachlorobenzene for porphyrin production, are Lindane, the y-isomer = 1, a =0.5, P = 0.3, E =0.25, 5 =0.15. These results may in part reflect the relative stability of the isomers whose structures are given by Hornstein [67b]. The hexahydrobromo derivative had no activity [67a]. 

Studies of porphyrin production in rats treated with DDC by gastric tube (300 mg/kg) revealed a decrease in liver ATP of 50% within 2 hours, while porphyrins increased continuously between 2 and 6 hours. On the other hand, intravenous administration of high doses of ATP was found to decrease the porphyria [Gajdos and Gajdos-Torok, 4]. Studies on chick embryo liver cells suggested that the decrease in porphyrin formation may not have been due to a lowering of ALA-synthetase activity but rather to an effect on some intermediate steps of heme biosynthesis [128]. When ATP, NADPH, ascorbate, orpiperonyl butoxide was added to the culture medium, porphyrin formation was diminished but ALA-synthetase activity was not appreciably affected. 

Lee SY, Vedamuthu ER, Washam CJ and Reinbold GW (1970) Diacetyl production by Propionibacterium shermanii in milk cultures. Can J Microbiol 16 1231-1242 Lee WL, Schalita AR, Pon-Fitzpatrick MB (1978) Comparative studies of porphyrin production in Propionibacterium acnes and Propionibacterium granulosum. J Bacteriol 133 811-815... 

The porphyrias result from inherited deficiencies in one of the seven enzymes of heme biosynthetic pathway (Fig. 31.1) [1]. Heme synthesis is most prominent in two organs, in bone marrow and liver. Therefore, porphyrias are classified as hepatic porphyrias or as erythropoietic porphyrias according to the tissue of excess porphyrin production. 

The results of a recent study on the inhibition of toxin and porphyrin production caused by the addition of small amounts of iron to the medium... 

---