An investigation of the behavior of protoporphyrin IX, deuteroporphyrin IX, haematoporphyrin IX and coproporphyrin III in aqueous solution revealed extensive and complex aggregation processes. Protoporphyrin appears to be highly aggregated under all conditions studied. At concentrations below 4 muM, aggregation of deutero-, haemato- and coproporphyrin is probably restricted to dimerization. At ...

Gun4 has been implicated in a developmental signaling pathway between the chloroplast and the nucleus involving magnesium protoporphyrin IX (MgP(IX)), the first dedicated intermediate in the chlorophyll biosynthetic pathway. Here we present the crystal structure of Thermosynechococcus elongatus Gun4 at 1.5 A, describe the binding affinities of Gun4 for substrate and product porphyrin molecules,...

1. Iron protoporphyrin IX was required for the growth of H. influenzae. It could be replaced by protoporphyrin IX. When grown on protoporphyrin evidence was obtained for the presence of Fe porphyrin in the organism. It was concluded that the organism could insert iron into the protoporphyrin ring. 2. In the smooth strains, other porphyrins containing no iron such as deutero-, hemato-, meso-, an...

The oxidation of protoporphyrinogen IX to protoporphyrin TX in yeast cells is enzyme-dependent. The enzyme, protoporphyrinogen oxidase, associated with purified mitochondria isolated from Saccharomyces cereuisiae was solubilized by sonic treatment in the presence of detergent and partially purified. The molecular weight of the enzyme was 180,000 f 18,000. The purified preparation could be store...

Fmoc-protected amine derivatives of Protoporphyrin IX were synthesized by two original methods using solid-phase chemistry. The new compounds represent unsymmetrical scaffolds suitable for the generation of a large range of peptidic porphyrin derivatives through SPPS strategy.

In this report we describe two nonallelic Mendelian protoporphyrin accumulating mutants brs-I and bre-1. Results of experiments with these mutants lead us to postulate that porphyrin biosynthesis branches into light and dark steps between protoporphyrin-IX and magnesium protoporphyrin. We hypothesize that the br e locus controls a dark step while the br s locus either controls a step in the mai...