Biomaterial Database

Conformation of abortifacient proteins: trichosanthin, alpha-momorcharin and beta-momorcharin. 1986

S Kubota, and H W Yeung, and J T Yang

The conformations of three abortifacient proteins, trichosanthin from the Chinese herb Tianhuafen and alpha- and beta-momorcharin from the Chinese herb Kuguazi, were studied by circular dichroism. Their spectra in the ultraviolet region (188-250 nm) were similar to each other and also pH-independent (between pH 5 and 9). All three proteins contained about 30% helix, as compared with 39% for trichosanthin by X-ray diffraction study, and 40-60% beta-sheets, but had no beta-turns, suggesting a structural homology among the proteins. The addition of 20 mM sodium dodecyl sulfate nearly doubled the helicity of beta-momorcharin at the expense of beta-sheets but had a small effect on the conformation of alpha-momorcharin, whereas the corresponding change in conformation for trichosanthin was in between the two momorcharins. This implies a marked difference in stability of the three proteins against the surfactant.

UI	MeSH Term	Description	Entries
D010940	Plant Proteins	Proteins found in plants (flowers, herbs, shrubs, trees, etc.). The concept does not include proteins found in vegetables for which PLANT PROTEINS, DIETARY is available.	Plant Protein,Protein, Plant,Proteins, Plant
D011487	Protein Conformation	The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).	Conformation, Protein,Conformations, Protein,Protein Conformations
D002942	Circular Dichroism	A change from planar to elliptic polarization when an initially plane-polarized light wave traverses an optically active medium. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Circular Dichroism, Vibrational,Dichroism, Circular,Vibrational Circular Dichroism
D000019	Abortifacient Agents	Chemical substances that interrupt pregnancy after implantation.	Abortifacient Effect,Abortifacient Effects,Abortifacients,Contraceptive Agents, Postconception,Agents, Abortifacient,Agents, Postconception Contraceptive,Effect, Abortifacient,Effects, Abortifacient,Postconception Contraceptive Agents
D000020	Abortifacient Agents, Nonsteroidal	Non-steroidal chemical compounds with abortifacient activity.	Abortifacient Agents, Non-Steroidal,Abortifacient Agents, Non Steroidal,Agents, Non-Steroidal Abortifacient,Agents, Nonsteroidal Abortifacient,Non-Steroidal Abortifacient Agents,Nonsteroidal Abortifacient Agents
D000596	Amino Acids	Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.	Amino Acid,Acid, Amino,Acids, Amino
D012269	Ribosomal Proteins	Proteins found in ribosomes. They are believed to have a catalytic function in reconstituting biologically active ribosomal subunits.	Proteins, Ribosomal,Ribosomal Protein,Protein, Ribosomal
D015978	Trichosanthin	Plant-derived ribosome-inactivating protein (RIP) purified from the Chinese medicinal herb tian-hua-fen which is obtained from the root tubers of Trichosanthes kirilowii. It has been used as an abortifacient and in the treatment of trophoblastic tumors. GLQ223 (Compound Q), a highly purified form of trichosanthin, has been proposed as antiviral treatment for AIDS.	Compound Q,alpha-Trichosanthin,GLQ-223,GLQ223,T'ien-hua-fen,Tian-hua-fen,GLQ 223,alpha Trichosanthin
D054788	Ribosome Inactivating Proteins	N-Glycosidases that remove adenines from RIBOSOMAL RNA, depurinating the conserved alpha-sarcin loop of 28S RIBOSOMAL RNA. They often consist of a toxic A subunit and a binding lectin B subunit. They may be considered as PROTEIN SYNTHESIS INHIBITORS. They are found in many PLANTS and have cytotoxic and antiviral activity.	RIP Ribosome Inactivating Proteins,RNA N-Glycosidase,Polynucleotide Adenosine Glycosidase,RIP (Ribosome Inactivating Proteins),RNA Glycosylase,rRNA N-Glycosylases,Adenosine Glycosidase, Polynucleotide,Glycosidase, Polynucleotide Adenosine,Glycosylase, RNA,Inactivating Proteins, Ribosome,N-Glycosidase, RNA,N-Glycosylases, rRNA,Proteins, Ribosome Inactivating,RNA N Glycosidase,rRNA N Glycosylases