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T X Dong

Publications and source records attributed to T X Dong.

7 recordsLinked to original sources

Isolation and characterization of a novel ribosome-inactivating protein, beta-kirilowin, from the seeds of Trichosanthes kirilowii.

A novel ribosome-inactivating protein designated beta-kirilowin was isolated from the seeds of Trichosanthes kirilowii. The proteins exhibited strong abortifacient activity in pregnant mice and produced a single band after SDS-polyacrylamide gel electrophoresis with an apparent mol. wt. of 27,500 daltons. It was active in inhibiting the cell-free translation system with an ID50 of about 1.8 ng/ml. No cross-reactivity with trichosanthin could be detected by immunodiffusion. Sequence comparison of the first 10 residues of beta-kirilowin with ribosome-inactivating proteins isolated from T. kirilowii such as trichosanthin, trichokirin and karasurin indicated 70%, 60% and 70% identity, respectively.

Abortifacient Agents↗

Characterization of Mirabilis antiviral protein--a ribosome inactivating protein from Mirabilis jalapa L.

A protein was purified from root tubers of Mirabilis jalapa to homogeneity by ion-exchange chromatography on CM-Sepharose CL-6B and FPLC on Mono-S column. The purified protein was confirmed to be Mirabilis antiviral protein (MAP). However, in addition to its antiviral property, the MAP was demonstrated to possess abortifacient activity in pregnant mice, inhibitory effect on cell-free protein synthesis and antiproliferative effect on tumor cells. As judged from its biological and physiochemical properties, MAP is a type I ribosome-inactivating protein.

Abortifacient Agents↗

alpha-Kirilowin, a novel ribosome-inactivating protein from seeds of Trichosanthes kirilowii (family Cucurbitaceae): a comparison with beta-kirilowin and other related proteins.

A novel ribosome-inactivating protein (RIP) designated alpha-kirilowin was isolated from the seeds of Trichosanthes kirilowii. The molecular weight of alpha-kirilowin was estimated by SDS-polyacrylamide gel electrophoresis to be 28 800 Da, which is slightly larger than another previously characterized ribosome-inactivating protein, beta-kirilowin. The amino-acid composition of alpha-kirilowin grossly resembled beta-kirilowin and other ribosome-inactivating proteins isolated from T. kirilowii tissues, including trichokirin, trichosanthin and karasurin. Intense immunological cross-reactivity between the two kirilowins was detected by immunodiffusion. The N-terminal sequence of alpha-kirilowin was identical to that of beta-kirilowin, at least in the first ten residues. Peptide fingerprinting indicated both kirilowins were closely related. Biological activities as determined by inhibition of protein synthesis in a cell-free system, suppression of [3H]-thymidine incorporation into mouse melanoma cells and induction of abortion in mice were very similar for both kirilowins. We propose that the size difference between alpha- and beta-kirilowin is either due to a C-terminal extension in alpha-kirilowin or differences in glycosylation, or a combination of both.

Abortifacient Agents↗