[Key aromatic amino acids of anti-hepatoma activity on Parasporin-2].
Nine mutants (P2M1-9) were obtained using PCR with 5-BU based on DNA template (P2Y) encoding the active region of Parasporin-2. Mutant proteins were purified after expressing in E. coli BL21 cells, followed by assayed against hepatoma cells and normal liver cells by MTT. They showed diverse anti-hepatoma activities, in which two mutant proteins, P2M1 and P2M8, exhibited high cytotoxicity against hepatoma cell lines SMMC7721 and Be17402, meanwhile leaving normal liver cells Chang-liver unaffected. Structural comparison among P2Y, P2M1 and P2M8 showed that the length of beta-sheet or beta-fold, and the amount of alpha helix greatly affected the anti-hepatoma activity of Parasporin-2. Results based on amino acid alignment, molecular docking between P2Y, P2M1 or P2M8 and receptor, and mimic mutation demonstrated that amino acid residues at the sites of 52, 56, 58 and 208 on P2Y, especially the aromatic amino acids such as Trp, Phe, and Tyr were involved in the interactions.
Department of Bioengineering and Biotechnology, College of Chemical Engineering, Huaqiao University, Xiamen 361021, Fujian, China.
Limin
L
Liao
Shufang
S
Lin
Ling
L
Tian
Aiming
A
Chen
Yi
Y
Lin
D000595:Amino Acid Sequence; D024322:Amino Acids, Aromatic / Q000096:biosynthesis / Q000235:genetics* / Q000494:pharmacology; D000970:Antineoplastic Agents / Q000494:pharmacology*; D006528:Carcinoma, Hepatocellular / Q000473:pathology; D045744:Cell Line, Tumor; D004731:Endotoxins / Q000737:chemistry* / Q000494:pharmacology*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D006801:Humans; D008113:Liver Neoplasms / Q000473:pathology; D008969:Molecular Sequence Data; D050505:Mutant Proteins / Q000494:pharmacology*; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000235:genetics / Q000494:pharmacology
D024322:Amino Acids, Aromatic; D000970:Antineoplastic Agents; D004731:Endotoxins; D050505:Mutant Proteins; D011994:Recombinant Proteins; C515506:parasporin-2, Bacillus thuringiensis