annotation rule: PRU00680

General rule information [?]

Accession PRU00680
Dates 18-DEC-2007 (Created)
31-MAY-2018 (Last updated, Version 5)
Data class Domain
Name Alpha-lactalbumin / lysozyme C family
Function Alpha-lactalbumin, a regulatory protein in milk, and lysozyme (EC C (chicken type), which acts as a bacteriolytic enzyme, belong to a family of proteins with eight conserved cysteines that form four disulfide bonds. Alpha-lactalbumin lacks the enzymatic activity and the corresponding Glu and Asp residues. Alpha-lactalbumin binds a calcium ion, while most lysozyme C do not bind calcium.

Propagated annotation [?]

Description [?]

case <FTGroup:1>
+ AltName: Full=lysozyme C; EC=; AltName: Full=1,4-beta-N-acetylmuramidase C;

Comments [?]

Function Lysozymes have primarily a bacteriolytic function; those in tissues and body fluids are associated with the monocyte-macrophage system and enhance the activity of immunoagents.
Catalytic activity Hydrolysis of (1->4)-beta-linkages between N-acetylmuramic acid and N-acetyl-D-glucosamine residues in a peptidoglycan and between N-acetyl-D-glucosamine residues in chitodextrins.
end case

Similarity Belongs to the glycosyl hydrolase 22 family.

Cross-references [?]


Gene Ontology [?]

case <FTGroup:1>
GO:0003824; Molecular function: catalytic activity.
GO:0019835; Biological process: cytolysis.
GO:0042742; Biological process: defense response to bacterium.
GO:0016798; Molecular function: hydrolase activity, acting on glycosyl bonds.
GO:0008152; Biological process: metabolic process.
GO:0016787; Molecular function: hydrolase activity.
end case

case <Feature:PS51348:85=D> and <Feature:PS51348:90-91=D-D>
GO:0005509; Molecular function: calcium ion binding.
end case

Keywords [?]

case <FTGroup:1>
end case

case <Feature:PS51348:85=D> and <Feature:PS51348:90-91=D-D>
end case

case <FTTag:disulf>
end case

Features [?]

From: PS51348
Key     From     To       Description   Tag   Condition   FTGroup
ACT_SITE     35     35             E   1
ACT_SITE     52     52             D   1
case <Feature:PS51348:85=D> and <Feature:PS51348:90-91=D-D>
CA_BIND     81     92                
end case

DISULFID     6     125           disulf   C-x*-C  
DISULFID     30     114           disulf   C-x*-C  
DISULFID     64     80           disulf   C-x*-C  
DISULFID     76     94           disulf   C-x*-C  

Additional information [?]

Size range 110-140 amino acids
Related rules None
Repeats 1
Topology Undefined
Example Q659U0 (LYSC_LEPWE)
Scope Eukaryota; Metazoa


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UniProtKB rule member sequences [?]