Purification and molecular cloning of an inducible Gram-negative bacteria-binding protein from the silkworm, Bombyx mori

摘要

A 50-kDa hemolymph protein, having strong affinity to the cell wall of Gram(-) bacteria, was purified from the hemolymph of the silkworm, Bombyx mori. The cDNA encoding this Gram( - ) bacteria-binding protein (GNBP) was isolated from an immunized silkworm fat body cDNA library and sequenced. Comparison of the deduced amino acid se- quence with known sequences revealed that GNBP contained a region displaying significant homology to the putative catalytic region of a group of bacterial β-1,3 glucanases and β-1,3-1,4 glucanases.