Linked Life Data

2517477

Source:http://linkedlifedata.com/resource/pubmed/id/2517477

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11-12
pubmed:dateCreated
1990-6-7
pubmed:abstractText
Biotinidase was purified from human breast milk (4,000-fold), and was compared with human serum biotinidase (enriched 30,000-fold). The molecular weight of milk enzyme was 68,000 Da as determined by SDS-PAGE. It was definitely smaller than that of serum biotinidase (Mr = 76,000). Isoelectric point of milk biotinidase was 4.6, whereas that of serum biotinidase was 4.3. Sialic acid content in milk biotinidase was less than that found in serum enzyme. N-Acetyl-galactosamine was present in milk enzyme, whereas it was absent in serum enzyme. Milk biotinidase is O-glycosylated, whereas serum biotinidase is N-glycosylated. These differences in glycosylation suggest the existence of different types of excretion mechanisms between milk and serum biotinidase. Both biotinidases were found to be thiol-type enzyme, however, the extent of activation of the enzyme by 2-mercaptoethanol was 13-fold in milk, whilst the serum enzyme was activated only 1.5-fold. Km for biotinyl-4-amino-benzoate was 22 microM in milk enzyme and 50 microM in serum enzyme. Competitive inhibition by biotin (Ki) of milk enzyme was 43 microM and 1.3 mM for serum enzyme. These results suggest the structural differences at or near the active site of the each enzyme.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0300-9084
pubmed:author
pubmed:issnType
Print
pubmed:volume
71
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1163-9
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:articleTitle
Comparative study on human milk and serum biotinidase.
pubmed:affiliation
National Children's Medical Research Center, Division of Metabolism, Tokyo, Japan.
pubmed:publicationType
Journal Article, Comparative Study