The domain within your query sequence starts at position 41 and ends at position 373; the E-value for the Glyco_hydro_56 domain shown below is 3e-137.

PVYQRKPFIAAWNAPTDLCLIKYNLTLNLKVFQMVGSPRLKDRGQNVVIFYANRLGYYPW
YTSEGVPINGGLPQNTSLQVHLKKAAQDINYYIPSENFSGLAVIDWEYWRPQWARNWNTK
DIYRQKSRTLISDMKENISAADIEYSAKATFEKSAKAFMEETIKLGSKSRPKGLWGYYLY
PDCHNYNVYATNYTGSCPEEEVLRNNDLSWLWNSSTALYPAVSIRKSFADSENTLHFSRF
RVRESLRISTMTSQDYALPVFVYTQLGYKEEPLLFLSKQDLISTIGESAALGAAGIVVWG
DMNLTSSEENCTKVNRFVNSDFGSYIINVTRAA

Glyco_hydro_56

Glyco_hydro_56
PFAM accession number:PF01630
Interpro abstract (IPR018155):

O-Glycosyl hydrolases ( EC 3.2.1. ) are a widespread group of enzymes that hydrolyse the glycosidic bond between two or more carbohydrates, or between a carbohydrate and a non-carbohydrate moiety. A classification system for glycosyl hydrolases, based on sequence similarity, has led to the definition of 85 different families [ (PUBMED:7624375) (PUBMED:8535779) ]. This classification is available on the CAZy (CArbohydrate-Active EnZymes) website.

Glycoside hydrolase family 56 comprises enzymes with only one known activity; hyaluronidase EC 3.2.1.35 .

The venom of Apis mellifera (Honeybee) contains several biologically-active peptides and two enzymes, one of which is a hyaluronidase [ (PUBMED:7682712) ]. The amino acid sequence of bee venom hyaluronidase contains 349 amino acids, and includes four cysteines and a number of potential glycosylation sites [ (PUBMED:7682712) ]. The sequence shows a high degree of similarity to PH-20, a membrane protein of mammalian sperm involved in sperm-egg adhesion, supporting the view that hyaluronidases play a role in fertilisation [ (PUBMED:7682712) ].

PH-20 is required for sperm adhesion to the egg zona pellucida; it is located on both the sperm plasma membrane and acrosomal membrane [ (PUBMED:2269661) ]. The amino acid sequence of the mature protein contains 468 amino acids, and includes six potential N-linked glycosylation sites and twelve cysteines, eight of which are tightly clustered near the C terminus [ (PUBMED:2269661) ].

GO process:carbohydrate metabolic process (GO:0005975)
GO function:hyalurononglucosaminidase activity (GO:0004415)

This is a PFAM domain. For full annotation and more information, please see the PFAM entry Glyco_hydro_56