This paper reports the optimized electro-transformation parameters of Bacillus thuringiensis plasmid-free mutant strain BMB171 by electroporation, and expressing effect of several cry genes introduced in this recipient. It showed that a highest electro-transformation frequency could be obtained, when SG solution was used as the buffer, and a 10.0V/cm of field strength, one time of pulse as well as a growth phase of recipient cells at the exponential phase (OD650nm value was 0.2~0.3) were selected. The highest of electro-transformation frequency with pHT3101 could reach at 8 ?107 hansformants/?g DNA. The transformation frequencies increased at linear velocity as the concentration increase of pHT3101 from 54.69pg/ml to 3.50?g/mL, then reached saturation afterwards. All plasmids introduced in BMB171 could produce characteristic insecticidal crystal proteins through expression of relevent cry genes carried by them. Meanwhile, these insecticidal crystal proteins could form parasporal crystals, which have characteristic geometric shapes.

Sup35 in its native state is a translation termination factor in Saccharomyces cerevisiae. The prion domain of Sup35p can form amyloid-like proteinaceous fibrils in vitro and in vivo. Furthermore, the in-register cross beta-sheet structure of Sup35p amyloid fibrils is similar to those formed in other species. Therefore, studies on mechanism of Sup35p self-assembly can be an appropriate model to study protein misfolding-related diseases and prion biology. Because of its ability to self-assemble into nanowires, the prion domain of Sup35p has been widely used in biotechnology and nanotechnology.
Amino Acid Sequence ; Amyloid ; chemistry ; metabolism ; Molecular Sequence Data ; Peptide Termination Factors ; chemistry ; Prions ; chemistry ; Protein Conformation ; Saccharomyces cerevisiae ; genetics ; metabolism ; Saccharomyces cerevisiae Proteins ; chemistry