Enzymes - Heme

Heme-using

Enzymes, which use Heme as a cofactor

Distribution of Heme over enzyme reaction space (E.C.)

The E.C. tree highlights the enzymes that use the cofactor on a tree of all known E.C. numbers. Thus, it illustrates how frequently the cofactor is used in enzyme reactions and where these reactions are located withing the E.C. classification hierarchy.

In addition to the E.C. numbers extracted from primary literature, this graph also incudes the E.C. numbers that have been automatically extracted from several data resources.

E.C. tree

Profile of Heme-containing reactions

The E.C. wheel is a pie chart-based representation of the enzyme reactions this cofactor is involved in. The reactions are identified by E.C. number. The colouring is performed by E.C. class. The figure has four levels of circles which correspond to the four levels of the E.C. classification hierarchy. Partial and full E.C. numbers are displayed where space suffices. Each area within the outer two rings corresponds to one full E.C. serial number.

In addition to the E.C. numbers extracted from primary literature, this graph also incudes the E.C. numbers that have been automatically extracted from several data resources.

E.C. wheel	Legend

Heme-synthesising

Enzymes involved in Heme biosynthesis

Further information

In mammals, 8 enzymes are involved in heme biosynthesis [4].

The first enzyme in mammal heme biosynthesis (5-aminolevulinate synthase) uses PLP as a cofactor [IntEnz:2.3.1.7].

Hydroxymethylbilane synthase uses dipyrromethane, a cofactor that exclusively serves as a seed for the meta-ring in heme molecules. [ref?]

Heme also regulates ion channels (K+) [4].

Heme-recycling

Enzymes involved in Heme recycling

Heme-binding

Enzymes binding to Heme (mode unknown)

PROCOGNATE: proteins and cognate ligands

Protein domains that bind to this molecule

References

[1]	pubmed:20544970
[2]	pubmed:17898892
[3]	pubmed:18237198
[4]	pubmed:17785948
[5]	pubmed:20037471
[6]	pubmed:11293549