The name of this superfamily has been modified since the most recent official CATH+ release (v4_4_0). At the point of the last release, this superfamily was named:

"
Periplasmic binding protein-like II
".

Functional Families

Overview of the Structural Clusters (SC) and Functional Families within this CATH Superfamily. Clusters with a representative structure are represented by a filled circle.
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FunFam 757: Hydroxymethylbilane synthase (Porphobilinogen deam...

There are 1 EC terms in this cluster

Please note: EC annotations are assigned to the full protein sequence rather than individual protein domains. Since a given protein can contain multiple domains, it is possible that some of the annotations below come from additional domains that occur in the same protein, but have been classified elsewhere in CATH.

Note: The search results have been sorted with the annotations that are found most frequently at the top of the list. The results can be filtered by typing text into the search box at the top of the table.

EC Term Annotations Evidence
Hydroxymethylbilane synthase. [EC: 2.5.1.61]
4 porphobilinogen + H(2)O = hydroxymethylbilane + 4 NH(3).
  • The enzyme works by stepwise addition of pyrrolylmethyl groups until a hexapyrrole is present at the active center.
  • The terminal tetrapyrrole is then hydrolyzed to yield the product, leaving a cysteine-bound dipyrrole on which assembly continues.
  • In the presence of a second enzyme, EC 4.2.1.75, which is often called cosynthase, the product is cyclized to form uroporphyrinogen III.
  • If EC 4.2.1.75 is absent, the hydroxymethylbilane cyclizes spontaneously to form uroporphyrinogen I.
  • Formerly EC 4.3.1.8.
4 B0R7M2 B0R7M2 Q9HMY5 Q9HMY5
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