RRC ID 1531
Author Katayama H, Yokota H, Akao T, Nakamura O, Ohba M, Mekada E, Mizuki E.
Title Parasporin-1, a novel cytotoxic protein to human cells from non-insecticidal parasporal inclusions of Bacillus thuringiensis.
Journal J. Biochem.
Abstract Pro-parasporin-1 is a parasporal inclusion protein of the non-insecticidal Bacillus thuringiensis strain A1190. Cytotoxic fragments, named parasporin-1, were generated from pro-parasporin-1 by trypsin digestion. Parasporin-1 was purified by a combination of chromatography procedures based on the cytotoxic activity to HeLa cells. Two different fragments of 15-kDa and 56-kDa were detected in the purified parasporin-1 fraction. These fragments were tightly associated with each other and could not be separated by chromatography under conditions that preserve cytotoxic activity, indicating that the active form of parasporin-1 is a heterodimer of the 15- and 56-kDa fragments. Amino acid sequencing and MALDI-TOF mass spectrometric analysis revealed that parasporin-1 is generated from pro-parasporin-1 by trypsin digestion at Arg 93 and Arg 231. Of 12 human cell lines tested, parasporin-1 showed strong cytotoxicity to four cell lines derived from cancer tissues, but low to no cytotoxicity to the other cell lines. The time-courses of cytotoxicity indicated that the mode of action of parasporin-1 to sensitive cells differs from that shown for previously isolated cytotoxic proteins from Bacillus thuringiensis, Cyt proteins, and other bacterial pore-forming toxins. Thus, parasporin-1 is a novel cytotoxic protein to human cancer cells produced by B. thuringiensis, and may be useful as a tool to recognize and destroy specific cancer cells.
Volume 137(1)
Pages 17-25
Published 2005-1
DOI 10.1093/jb/mvi003
PII 137/1/17
PMID 15713879
MeSH Animals Bacillus thuringiensis / chemistry* Bacterial Proteins / chemistry Bacterial Proteins / isolation & purification Bacterial Proteins / toxicity* Bacterial Toxins / chemistry Bacterial Toxins / isolation & purification Bacterial Toxins / toxicity* Cell Line Cercopithecus aethiops Endotoxins / chemistry Endotoxins / isolation & purification Endotoxins / toxicity* Humans Mice
IF 2.35
Times Cited 38
Human and Animal Cells Jurkat Sawano Hep G2 HL60 NIH3T3-3 MOLT-4 A549 MRC-5 HeLa Vero CACO-2