Protoporphyrins are tetrapyrroles containing the following side chains: The term Side chain can have different meanings depending on the context: In chemistry and biochemistry a side chain is a part of a molecule attached to a core structure. ...

• methyl (4)
• propionic acid (2)
• vinyl (2)

In the metabolism of porphyrin, "protoporphyrin IX" is created by the enzyme protoporphyrinogen oxidase, and the enzyme ferrochelatase converts it into heme. In chemistry a methyl-group is a hydrophobic Alkyl functional group which is derived from methane (CH4). ... Propionic acid (systematically named propanoic acid) is a naturally occurring carboxylic acid with chemical formula CH3CH2COOH. In the pure state, it is a colorless, corrosive liquid with a pungent odor. ... Vinyl products (such as these records) come in many colors. ... A porphyrin is a heterocyclic macrocycle made from 3 pyrrole subunits and one pyrroline subunit, and linked on opposite sides through 4 methine bridges. ... Protoporphyrinogen oxidase (EC 1. ... Ferrochelatase is an enzyme involved in the eighth step of porphyrin metabolism, converting protoporphyrin IX into heme. ... Structure of Heme b A heme or haem is a prosthetic group that consists of an iron atom contained in the center of a large heterocyclic organic ring called a porphyrin. ...

Protoporphyrins are deposited in the shells of the eggs of some birds as a brown or red pigment, either as a ground colour or as spotting. This occurs in most passerine species, some ground-nesting non-passerines, such as waders, gulls, nightjars and sandgrouse, where it provides camouflage, and some parasitic cuckoos, which need to mimic their passerine hosts' eggs. An average Whooping Crane egg is 102 mm long, and weighs 208 grams In some animals, an egg (Latin ovum) is the zygote, resulting from fertilization of the ovum. ... Orders Many - see section below. ... Families Many, see text A passerine is a bird of the giant order Passeriformes. ... Families Charadridae Jacanidae Rostratulidae Ibidorhynchidae Recurvirostridae Haematopodidae Scolopacidae Dromadidae Burhinidae Glareolidae Thinocoridae Waders, called Shorebirds in North America (where wader is used to refer to long-legged wading birds such as storks and herons), are members of the order Charadriiformes, excluding the more marine web-footed seabird groups. ... Genera Gulls are seabirds in the family Laridae. ... Genera Nyctiprogne Podager Lurocalis Chordeiles Nyctidromus Phalaenoptilus Siphonorhis Nyctiphrynus Caprimulgus Macrodipteryx Hydropsalis Uropsalis Macropsalis Eleothreptus Eurostopodus Nightjars are medium-sized nocturnal birds with long wings, short legs and very short bills that usually nest on the ground. ... Genera Pterocles Syrrhaptes The sandgrouse are a group of 16 near passerine bird species in the order Pteroclidiformes. ... Brood parasite is a term specifically applied to birds or insects that leave their eggs in the nests of other birds or insects to be raised. ... Genera See text. ...

Protoporphyrins strengthen the egg shell, and are deposited where the shell is too thin as a result of calcium shortage. Spotting therefore tend to be heavier where the local soil is calcium-deficient, and in the eggs laid last in a clutch.

External links

• MeSH Protoporphyrins
• Pubchem - protoporphyrin IX