Molecular cloning of cDNA for lipopolysaccharide-binding protein from the hemolymph of the American cockroach, Periplaneta americana. Similarity of the protein with animal lectins and its acute phase expression

Abstract

A previous paper described the purification of a calcium-dependent lipopolysaccharide-binding protein from the hemolymph of Periplaneta americana (Jomori, T., Kubo, T., and Natori, S. (1990) Eur. J. Biochem. 190, 201-206). This paper describes the molecular cloning and characterization of cDNA for the LPS-binding protein. This protein was found to have a carbohydrate-recognition domain at its carboxyl terminus containing amino acid sequences that are conserved in various mammalian C-type lectins. It was also shown to contain an N-linked carbohydrate chain, and the amino acid residue carrying this chain was assigned as Asn at position 56 (23rd amino acid residue from the amino terminus). Northern blot analysis revealed the presence of multiple mRNAs that hybridized with this cDNA and transient increases in their content after injection of Escherichia coli into adult Periplaneta, suggesting that the LPS-binding protein plays a role in the acute phase response of this insect.