The domain within your query sequence starts at position 6 and ends at position 99; the E-value for the Pterin_4a domain shown below is 9.5e-33.

HRLSAEERDQLLPNLRAVGWNEVEGRDAIFKQFHFKDFNRAFGFMTRVALQAEKLDHHPE
WFNVYNKVHITLSTHECAGLSERDINLASFIEQV

Pterin_4a

Pterin_4a
PFAM accession number:PF01329
Interpro abstract (IPR001533):

Pterin 4 alpha carbinolamine dehydratase is also known as DCoH. DCoH is the dimerisation cofactor of hepatocyte nuclear factor 1 (HNF-1) that functions as both a transcriptional coactivator and a pterin dehydratase [ (PUBMED:8897596) ]. X-ray crystallographic studies have shown that the ligand binds at four sites per tetrameric enzyme, with little apparent conformational change in the protein.

GO process:tetrahydrobiopterin biosynthetic process (GO:0006729)
GO function:4-alpha-hydroxytetrahydrobiopterin dehydratase activity (GO:0008124)

This is a PFAM domain. For full annotation and more information, please see the PFAM entry Pterin_4a