5 research outputs found
1차원 나노물질의 정제와 거시적 정렬에 관한 연구
No full text학위논문(박사) - 한국과학기술원 : 생명화학공학과, 2024.2,[v, 78 p. :]Emerging 1D nanomaterials, with their unique and potentially transformative properties, hold great promise for a variety of practical applications, provided they can be obtained in a pure state. An equally crucial aspect for future applications of these 1D materials is their assembly, which must preserve their inherent unique characteristics. Our study focuses on establishing a general framework for preparing 1D materials and leveraging their macroscopic properties for practical uses. As a specific case study, we delve into boron nitride nanotubes, elaborating on various purification methods and assembly techniques to exploit their extraordinary macroscopic properties.한국과학기술원 :생명화학공학과
스트렙토마이세스 그리세우스 프로테아제와 스트렙토키나제 유전자의 발현 및 프로펩타이드의 역할
No full text학위논문(박사) - 한국과학기술원 : 생물과학과, 1998.2, [ xii, 130 p. ]Streptomyces griseus protease A (SGPA), B (SGPB) and Trypsin (SGT) are the extracellular serine proteases from Streptomyces griseus. SGPA and SGPB are chymotrypsin-like protease and SGT is a trypsin-like protease. It is such an interesting feature that prepro-sequence of SGPA and SGPB quite differ from that of SGT. SGPA, SGPB and SGT are very homologous not only to one another, but also to mammalian serine proteases. Streptokinase (SK) is an extracellular protein from several strains of streptococci that functions a plasminogen activator, a fibrinolytic agent without its protease activity. It has been proposed that these serine family proteases were related to Streptokinase in amino acid homology and molecular evolution. In our previous report, the genes encoding S. griseus protease A (sprA), B (sprB), Trypsin (sprT) were cloned from S. griseus ATCC 10137. In this study, the nucleotide sequence of SGPA and SGPB genes was determined and characterized. And several vectors for expression and secretion were constructed to develop the appropriate expression system, and the wild and mutated types of SGPA, SGPB, SGT and SK genes were expressed in E. coli, Bacillus subtilis and Streptomyces lividans. In addition the role of the propeptide of the microbial serine proteases was investigated.
The amino acid sequence deduced from the nucleotide sequence suggests that S. griseus protease A and B are produced as a precursor consisting of three portions. In the case of SGPB, an amino-terminal pre-sequence (38 amino acid residues), a pro-sequence (76 amino acid residues), and mature protease (185 amino acid residues). The first expression vectors for sprA and sprB were constructed by subcloning the gene fragments into multi-cloning site of E. coli-S. lividans shuttle vector. S. lividans 1326 transformed with the recombinant plasmids showed clear zone activity around its colony on the skim milk-YD plate. When the protease activity from culture medium was assayed using artifici...한국과학기술원 : 생물과학과
