Vitelline membrane outer layer protein 1 homolog (VMO1) belongs to the VMO1 family is a 202 amino acid secreted protein. Exact function not known, component of the outer membrane of the vitelline layer of the egg. Seems to be able to synthesize N-acetylchito-oligosaccharides (n=14-15) from hexasaccharides of N-acetylglucosamine in a manner similar to the transferase activity of lysozyme.