The highly abundant protein Ag-lbp55 from Ascaridia galli represents a novel type of lipid-binding proteins

Rositsa Jordanova, Georgi Radoslavov, Peter Fischer, Andrew Torda, Friedrich Lottspeich, Raina Boteva, Rolf D. Walter, Ilia Bankov, Eva Liebau

Research output: Contribution to journalArticlepeer-review

6 Scopus citations


Lipid-binding proteins exhibit important functions in lipid transport, cellular signaling, gene transcription, and cytoprotection. Their functional analogues in nematodes are nematode polyprotein allergens/antigens and fatty acid and retinoid-binding proteins. This work describes a novel 55-kDa protein, Ag-lbp55, purified from the parasitic nematode Ascaridia galli. By direct N-terminal sequencing, a partial amino acid sequence was obtained that allowed the design of oligonucleotide primers to obtain the full-length cDNA sequence. Sequence analysis revealed the presence of an N-terminal signal peptide of 25 amino acid residues and a FAR domain at the C terminus. Data base searches showed almost no significant homologies to other described proteins. The secondary structure of Ag-lbp55 was predominantly α-helical (65%) as shown by CD spectroscopy. It was found to bind with high affinity fatty acids (caprylic, oleic, and palmitic acid) and their fluorescent analogue dansylaminoundecanic acid. Immunolocalization showed that Ag-lbp55 is a highly abundant protein, mainly distributed in the inner hypodermis and extracellularly in the pseudocoelomatic fluid. A similar staining pattern was observed in other pathogenic nematodes, indicating the existence of similar proteins in these species.

Original languageEnglish
Pages (from-to)41429-41438
Number of pages10
JournalJournal of Biological Chemistry
Issue number50
StatePublished - Dec 16 2005


Dive into the research topics of 'The highly abundant protein Ag-lbp55 from Ascaridia galli represents a novel type of lipid-binding proteins'. Together they form a unique fingerprint.

Cite this