Linked Life Data

10561541

Source:http://linkedlifedata.com/resource/pubmed/id/10561541

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
2000-1-11
pubmed:abstractText
The complete amino acid sequence of the Megathura crenulata hemocyanin functional unit KLH2-c was determined by direct sequencing and matrix-assisted laser desorption ionization mass spectrometry of the protein, and of peptides obtained by cleavage with EndoLysC proteinase, chymotrypsin and cyanogen bromide. This is the first complete primary structure of a functional unit c from a gastropod hemocyanin. KLH2-c consists of 420 amino acid residues. Circular dichroism spectra indicated approx. 31% beta-sheet and 29% alpha-helix contents. A multiple sequence alignment with other molluscan hemocyanin functional units revealed average identities between 41 and 49%, but 55% in case of Octopus hemocyanin functional unit c which is the structural equivalent to KLH2-c. KLH2-c has a molecular mass of approx. 48 kDa as calculated from its sequence and a measured mass of approx. 56 kDa; the mass difference is attributed to the sugar side chains usually decorating molluscan hemocyanin. However, inspection of the sequence of KLH2-c revealed no potential N-linked carbohydrate attachment sites, and this was supported by its inability to bind concanavalin A. Also KLH1-c was unreactive, whereas most, if not all, other functional units of KLH1 and KLH2 reacted positively to this lectin. On the other hand, peanut agglutinin specifically binds KLH2-c, indicating the presence of O-glycosidically linked carbohydrates in this functional unit. This contrasts to all other KLH functional units (including KLH1-c), which lack O-linked glycosides. The present results are discussed in view of the recent X-ray structure of the functional unit g from Octopus hemocyanin, and a published record of the Thomsen Friedenreich tumor antigenic epitope in KLH.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:day
16
pubmed:volume
1435
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
94-109
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
Primary structure and unusual carbohydrate moiety of functional unit 2-c of keyhole limpet hemocyanin (KLH).
pubmed:affiliation
Abteilung für Physikalische Biochemie, Physiologisch-chemisches Institut der Universität Tübingen, Hoppe-Seyler-Str. 4, D-72076, Tübingen, Germany. stanka.stoeva@unij-tuebingen.de
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't