We measured pigment concentration to verify the absence of biliverdin and protoporphyrin.

The resulting anemia is believed to be the result of a disturbance in the synthesis of the protoporphyrins.

It is based on the breakthrough for the photodynamic cancer therapy of the photosensitizer protoporphyrin IX (PPIX).

The sunlight activates the protoporphyrin molecules, which damage the surrounding tissue.

Complexed with zinc-ions (Zn 2+) it forms Zinc protoporphyrin.

A model of the Fe-protoporphyrin IX subunit of the Heme B cofactor.

Until recently, the test of choice for screening asymptomatic populations at risk was erythrocyte protoporphyrin (EP), commonly assayed as zinc protoporphyrin (ZPP).

Once inside these cells, it is enzymatically converted to protoporphyrin IX, a potent photosensitizer.

Until recently, the test of choice for screening asymptomatic populations at risk was erythrocyte protoporphyrin (EP), commonly assayed as zinc protoporphyrin (ZPP).

Examination of the eggshells revealed the presence of biliverdin and protoporphyrin.

ALA is converted in vivo to protoporphyrin IX, which is the active photosensitizer.

Doctors test blood to look for elevated levels of protoporphyrin.

Ferrochelatase, which catalyzes the insertion of iron into protoporphyrin IX, is quite sensitive to lead.

The enzyme ferrochelatase inserts iron into the ring structure of protoporphyrin IX to produce heme.

Some doctors will also ask for a stool sample to measure the level of protoporphyrin in the faeces.