Unpleasant specimens, sensitive analytes, and a lengthy chromatographic procedure were the main reasons we implemented fecal porphyrin analysis with a laboratory robot. We describe the system in detail and compare it with the same technique performed manually. The day-to-day variation of assays of standards was lower with the robot than with the manual operation: 8% (CV) for coproporphyrin I an...

Magnesium protoporphyrin IX methyltransferase (ChlM) catalyzes the formation of magnesium protoporphyrin IX monomethylester (MgPME) from magnesium protoporphyrin IX (MgP) in the chlorophyll synthesis pathway. However, no ChlM gene has yet been identified and studied in monocotyledonous plants. In this study, a spontaneous mutant, yellow-green leaf 18 (ygl18), was isolated from rice (Oryza sativ...

Fluorescence spectroscopy with six wavelengths (369 nm, 395 nm, 400 nm, 405 nm, 410 nm, 416 nm) was performed to determine the optimal excitation wavelength of exogenously induced Protoporphyrin-IX fluorescence in esophageal adenocarcinoma cells and Barrett’s esophageal tissue, as this might improve (pre)malignant lesion identification in Barrett’s esophagus. Esophageal adenocarcinoma cell...

BACKGROUND Heme oxygenase-1 (HO-1) is a stress-response enzyme implicated in cardioprotection. To explore whether HO-1 has a role in cardiac remodeling response, the effect of its overexpression on angiotensin II (Ang II)-induced cardiac hypertrophy was examined. METHODS AND RESULTS HO-1 was induced in cultured rat neonatal cardiomyocytes by treatment with cobalt protoporphyrin IX (CoPPIX) or...

The resolution and reconstitution of the Mg-protoporphyrin IX monomethyl ester oxidative cyclase system into a supernatant and a pellet fraction was accomplished by a procedure involving salt treatment followed by osmotic shock. Recombination of pellet and supernatant fractions was required for cyclase activity. This restoration effect could be demonstrated using either Mg-protoporphyrin IX or ...

Heme enzymes are ubiquitous in nature. Although these contain the same Fe-protoporphyrin IX cofactor their active site, they exhibit different structural and functional activities. This brief review focuses on reasons for this diversity mentions some attempts to mimic activity of heme enzymes. It also briefly discusses efforts expand catalytic repertoire enable new chemical transformations.

Magnesium protoporphyrin IX methyltransferase (ChlM), an enzyme in the chlorophyll biosynthetic pathway, catalyses the transfer of a methyl group to magnesium protoporphyrin IX (MgP) to form magnesium protoporphyrin IX monomethyl ester (MgPME). S-Adenosyl-L-methionine is the other substrate, from which a methyl group is transferred to the propionate group on ring C of the porphyrin macrocycle. ...

In evaluating the autofluorescence properties of normal and diseased skin we discovered that psoriatic plaques can emit a distinct red fluorescence when illuminated with UVA or blue light. Using a macrospectrofluorometer equipped with a 442 nm excitation laser, a sharp in vivo fluorescence emission peak around 635 nm could be demonstrated within the plaques of 34 of 75 (45%) patients with psori...

Fluorescence detection may help to demarcate skin cancer from normal skin, thus to reduce the potential of incomplete treatment resulting from unawareness of tumour extension in surrounding skin. In this study we evaluated the difference between autofluorescence of basal cell carcinomas (n = 21) and the normal-appearing skin surrounding them. Referring to the difference found, a point-by-point ...

Heme was a noncompetitive inhibitor (apparent K(i) and K'(i) = 0.043 mM) of a ferrisiderophore reductase purified from Bacillus subtilis; protoporphyrin IX had no effect. The cellular level of heme may partly regulate the function of this reductase to yield a controlled flow of iron into metabolism.