Haemin, iron(III)-protoporphyrin IX complex, and parallel-quadruplexed d(TTAGGG) have been shown to form a stable coordination complex which exhibits spectroscopic properties remarkably similar to those of haemoproteins.

We report protoporphyrin IX (PpIX) encapsulated pH-responsive micelles for cancer treatment. This system showed pH-responsive micellization/demicellization transition at tumoral acidic pH and enabled in vivo tumor diagnosis and therapy simultaneously.

Complexation of iron(II) protoporphyrin IX (Fe(2+)PP) into a genetically engineered heme pocket on recombinant human serum albumin (rHSA) creates an artificial hemoprotein which can bind O(2) reversibly at room temperature. Here we highlight a crucial role of a basic amino acid triad the entrance of the heme pocket in rHSA (Arg-114, His-146, Lys-190) for O(2) and CO binding to the prosthetic Fe...

The anorectic cobalt protoporphyrin (CoPP) is known to elicit short-term hypophagia and long-term weight loss through unknown mechanisms in the brains of experimental animals. The goal of this work was to determine 1) if the prolonged duration of action of CoPP is related to its prolonged retention within the brain; and 2) with the use of immunohistochemical detection of Fos, the product of the...

Two protoporphyrin IX (PpIX) adamantane derivatives were synthesized and then metallated with zinc. The Zn-PpIX derivatives, exhibiting a high singlet oxygen quantum yield, tested for their photodynamic activity against the HT-29 cell line. In order to enhance water-solubility cellular bioavailability, these photosensitizers encapsulated into hydrophobic cavity of cyclodextrins (CD) previously ...

PURPOSE Human blood contains low levels of protoporphyrin IX (PP IX), a photoactive compound that produces reactive oxygen species when exposed to light. It has been proposed that photoactivation of PP IX and subsequent generation of potentially tissue-damaging reactive oxygen may be a mechanism of retinal injury in retinopathy of prematurity (ROP). The purpose of this study is to determine an ...

We provide in vivo genetic and in vitro biochemical evidence that RegA directly regulates bacteriochlorophyll and carotenoid biosynthesis in Rhodobacter capsulatus. beta-Galactosidase expression assays with a RegA-disrupted strain containing reporter plasmids for Mg-protoporphyrin IX monomethyl ester oxidative cyclase (bchE), Mg-protoporphyrin IX chelatase (bchD), and phytoene dehydrogenase (cr...

Magnesium-protoporphyrin IX (Mg-PPn), which is formed through chelation of protoporphyrin IX (PPn) with Mg ion by Mg chelatase, is the first intermediate for the (bacterio)chlorophyll biosynthetic pathway. Interestingly, Mg-PPn provides peroxidase activity (approximately 4 × 10(-2) units/micrometer) detoxifying H2O2 in the presence of electron donor(s). The peroxidase activity was not detected ...

Cancer cells have been reported to exhibit an enhanced capacity for protoporphyrin IX (PpIX) synthesis facilitated by the administration of 5-aminolevulinic acid (ALA). We investigated the effect of ALA-based photodynamic therapy (PDT) on human cholangiocarcinoma cells (HuCC-T1). Since protoporphyrin IX (PpIX), a metabolite of ALA, can produce reactive oxygen species (ROS) under irradiation and...