Crystallization and preliminary X-ray crystallographic analysis of the functional form of BinB binary toxin fromBacillus sphaericus

Abstract

The binary toxin from Bacillus sphaericus consists of two proteins, BinA and BinB, which work together to exert toxicity against mosquito larvae. BinB is proposed to be a receptor-binding domain and internalizes BinA into the midgut cells, resulting in toxicity via an unknown mechanism. The functional form of BinB has been successfully crystallized. The crystals of BinB diffracted to a resolution of 1.75 Å and belong to space group P6 2 22, with unit-cell parameters a = b = 95.2, c = 154.9 Å . Selenomethionine-substituted BinB (SeMetBinB) was prepared and crystallized for experimental phasing. The SeMetBinB crystal data were collected at a wavelength of 0.979 Å and diffracted to a resolution of 1.85 Å .

Crystal structure of BinB: A receptor binding component of the binary toxin from Lysinibacillus sphaericus

“…Briefly, BinB was cloned and expressed as a soluble protein. To produce the 45‐kDa activated BinB, purified BinB was digested by trypsin at a trypsin:protoxin ratio of 1:20 (w:w) at 37°C for 2 h. The crystallization of BinB has been previously described …”