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  2. Porphobilinogen - Wikipedia

    en.wikipedia.org/wiki/Porphobilinogen

    Porphobilinogen (PBG) is an organic compound that occurs in living organisms as an intermediate in the biosynthesis of porphyrins, which include critical substances like hemoglobin and chlorophyll. [1] The structure of the molecule can be described as molecule of pyrrole with sidechains substituted for hydrogen atoms at positions 2, 3 and 4 in ...

  3. Hemoglobin - Wikipedia

    en.wikipedia.org/wiki/Hemoglobin

    [16] [17] From the known atomic mass of iron, he calculated the molecular mass of hemoglobin to n × 16000 (n=number of iron atoms per hemoglobin molecule, now known to be 4), the first determination of a protein's molecular mass. This "hasty conclusion" drew ridicule from colleagues who could not believe that any molecule could be so large.

  4. Tetrapyrrole - Wikipedia

    en.wikipedia.org/wiki/Tetrapyrrole

    Some tetrapyrroles form the active core of compounds with crucial biochemical roles in living systems, such as hemoglobin and chlorophyll. In these two molecules, in particular, the pyrrole macrocycle ring frames a metal atom, that forms a coordination compound with the pyrroles and plays a central role in the biochemical function of those ...

  5. Chlorophyll - Wikipedia

    en.wikipedia.org/wiki/Chlorophyll

    Chlorophyll f was announced to be present in cyanobacteria and other oxygenic microorganisms that form stromatolites in 2010; [13] [14] a molecular formula of C 55 H 70 O 6 N 4 Mg and a structure of (2-formyl)-chlorophyll a were deduced based on NMR, optical and mass spectra. [15]

  6. Metalloprotein - Wikipedia

    en.wikipedia.org/wiki/Metalloprotein

    There are only three major structural differences; a magnesium atom (Mg) in chlorophyll, as opposed to iron (Fe) in hemoglobin. Additionally, chlorophyll has an extended isoprenoid tail and an additional aliphatic cyclic structure off the macrocycle. Chlorophyll plays a crucial role in photosynthesis. It contains a magnesium enclosed in a ...

  7. Protoporphyrin IX - Wikipedia

    en.wikipedia.org/wiki/Protoporphyrin_IX

    Protoporphyrin IX is an organic compound, classified as a porphyrin, that plays an important role in living organisms as a precursor to other critical compounds like heme and chlorophyll. It is a deeply colored solid that is not soluble in water.

  8. Biological pigment - Wikipedia

    en.wikipedia.org/wiki/Biological_pigment

    Chlorophyll is the primary pigment in plants; it is a chlorin that absorbs blue and red wavelengths of light while reflecting a majority of green. It is the presence and relative abundance of chlorophyll that gives plants their green color. All land plants and green algae possess two forms of this pigment: chlorophyll a and chlorophyll b.

  9. Chromophore - Wikipedia

    en.wikipedia.org/wiki/Chromophore

    Examples are chlorophyll, which is used by plants for photosynthesis and hemoglobin, the oxygen transporter in the blood of vertebrate animals. In these two examples, a metal is complexed at the center of a tetrapyrrole macrocycle ring: the metal being iron in the heme group (iron in a porphyrin ring) of hemoglobin, or magnesium complexed in a ...