Two-dimensional electrophoresis analysis of proteins from the colleterial gland of silkworm (Bombyx mori L.) / 生物工程学报

In silkworm moth the colleterial gland markedly enlarged due to the secretion and accumulation of glue like substances before adult emergence. However, the Ng mutant female moth only secreted little glue-like substance and laid loose eggs naturally. In the present experiment, it was extracted the proteins of secretory part of the variety E981 and its Ng mutant line and analyzed by two-dimensional electrophoresis. More than 700 protein spots were resolved both in two samples and most of the proteins were distributed in the area from 30 kD to 70 kD and pH 4 - 8. Through the comparison and analysis, it was found that 4 proteins were only expressed in E981 and 2 proteins were only expressed in Ng mutant. Furthermore, there are about 29 proteins were expressed higher in 981 and about 15 proteins expressed volume were higher in Ng mutant. These differential proteins may be have some relations with the Ng mutant form and directly lead to the Ng mutant can't secret the glue-like substance.

Cloning and expression of the cecropin B-thanatin hybrid antimicrobial peptide in Escherichia coli / 生物工程学报

A 44-residue hybrid peptide (CB (1-24)-Arg-Ser-Tyr-Tan (4-21)) incorporating 1-24 residues of cecropin B (CB) and 4-21 residues of thanatin (Tan) was designed and constructed. The CB-Tan gene was cloned into expression plasmid pGEX-3X and expressed in E. coli BL21. The fusion protein was purified by affinity chromatography. After digested with enterokinase the gene product released with antibacterial activity and gave one band in Tricine-SDS-PAGE.