60 results about "Ribosome-inactivating protein" patented technology

The invention discloses a Cucurbita moschata protein 2 and a preparation method and application thereof, which relates to the field of biochemistry. The invention discloses a new ribosome inactivated protein extracted from flesh of Cucurbita moschata, namely the Cucurbita moschata protein 2 (type 2 Cucurbita moschata ribosome inactivated protein cucurmosin 2). The molecular weight of the Cucurbita moschata protein 2 is determined as 2, 7183Da by ESI-MS. The Cucurbita moschata protein 2 is put into phosphate buffer, citric acid buffer and Tris-HCl buffer in advance, and a single crystal for the diffraction of X-ray is produced taking carbowax as a precipitator. Through preliminary analysis, the crystal structure shows that the crystal is a type 1 ribosome inactivated protein with the functions of tumor and virus resistance, in particular human immunodeficiency virus resistance, thereby laying a material foundation for obtaining a protein for medicine use or preparing immunotoxin.

A method for detecting ribosome inactivating protein (RIP) activity in a sample is provided that involves contacting a sample that contains an RIP with an inventive substrate that is depurinated to form product. The product is hybridized to a template and cleaved by an apurinic / apyrimidinic endonuclease such that releasing the blocked 3′ end only in a sample that contains RIP activity. The 5′ end of the product serves as a primer for extension by a polymerase reaction. The newly synthesized strand complementary to the template is detected by RT-PCR processes. A kit is provided suitable for field or laboratory use.

The invention discloses a fusion toxin (rhVEGF121KDR / Rgel30) with specificity of VEGFR2 / KDR acceptor, and coding gene thereof and application thereof to prepare antitumor medicines. The fusion toxin is obtained by connecting the amino terminal (N terminal) of gelonium multiflorum ribosome inactivating protein rGEL30 to recombinant human vascular endothelial growth factor VEGF121 mutant through a connecting peptide, and the carboxyl terminal (C terminal) of the fusion toxin possesses endoplasmic reticulum positioning sequence. VEGF121KDR taken as a carrying tool helps the fusion toxin to specifically combine with VEGFR2 / KDR through high affinity, to be internalized and to enter tumor newborn blood vessel endothelial cells, then ribosome inactivating protein rGEL30 gives a play to toxin effect and kills tumor newborn blood vessel endothelial cells and further destroys newborn blood vessels of tumor tissue for reaching the purpose of inhibiting tumor, and also an endoplasmic reticulum positioning signal at the C terminal of the fusion toxin is capable of promoting free rGEL30 toxin to be gathered on rough endoplasmic reticulum, so that the antitumor effect of the fusion toxin is further enhanced.

The invention belongs to the technical field of bioengineering and specifically discloses a method for constructing a ribosome inactivating protein gene virus vector and expressing active proteins intumor cells through the ribosome inactivated protein gene virus vector. The method comprises the following steps that first, suitable ribosome inactivated proteins are selected, and codon optimizationfor humanized expression is conducted on mature region genes of the ribosome inactivated proteins; second, an adenovirus carrier of wild type and optimized genes is constructed, and recombinant viruses are packaged; and third, recombinant adenoviruses infect the tumor cells, the recombinant adenoviruses express proteins in the tumor cells through detection, and the anti-tumor effect of the recombinant adenoviruses is detected. According to the method, an alpha-charantin gene is subjected to codon optimization, an expression vector system for the adenoviruses capable of infecting the tumor cells of mammals is constructed so as to be suitable for expressing the active proteins in the tumor cells, and the defects that in the prior art, a prokaryotic cell expression system can only be expressed in escherichia coli when being used, and a plant virus vector can only be expressed in plant cells but cannot be expressed in the tumor cells and kill tumors when being used are overcome.

The invention provides jatropha curcas L. ribosome-inactivating protein and a preparation method thereof. The jatropha curcas L. ribosome-inactivating protein is separated and purified from cotyledon and / or endosperm of jatropha curcas L. seedlings which are generated by jatropha curcas L. seeds germinating for 4 to 49 days, relative molecular weight is 31.398kDa, an isoelectric point is 7.12, and a sequence of amino acid residue of an N-terminal of the ribosome-inactivating protein is shown as SEQ ID No: 1 in a sequence table. The invention further provides application of the jatropha curcas L. ribosome-inactivating protein in preparing medicines for treating tumor. The jatropha curcas L. ribosome-inactivating protein has an obvious anti-proliferative effect on human osteosarcoma U20S, human non-small cell lung cancer A549, human non-small cell lung cancer H1975 and human colon cancer HCT116; an in-vitro proliferation inhibition effect of the jatropha curcas L. ribosome-inactivating protein on the human osteosarcoma U20S is superior to that of Curcin and taxol; furthermore, toxicity to human normal kidney cells is lower.

This invention relates to a fusion protein that possess action of selectively kill tumour rebirth blood vessel endotheliocyte, and its application. This fusion protein through connecting peptide connect VEGF121 with amido end of sponge gourd seed ribosome inactivating protein(RIP) Luffin Alpha. The vascular endothelial cell growth factor VEGF121 act as means of delivery, make this fusion toxin idiosyncratic incorporate with vascular endothelial cell growth factor receptor F1k1 / KDR, thereby optionally ingress tumour rebirth vascular endothelial cell; the polypeptide possess amphipathic molecule character, by destroy lysosome membrane to promote the release of lysosome inside dissociate toxin molecule; the toxin carboxyl terminal endoplasmic reticulum loacting signal led toxin molecule( sponge gourd seed RIP Luffin Alpha) to target site to exert toxic effect, so to destroy rebirth blood vessel of tumour organization, cut off tumour blood supply, achieve the end of restraining tumor.

A fusion protein comprising at least one Type 1 Ribosome Inactivating Protein, polypeptide B; and at least one polypeptide A capable of viral entry inhibition; and / or at least one Cationic AntiMicrobial Peptide, polypeptide C.

Stable immunogenic composition capable of eliciting a robust and durable immune response yielding a measurable increase in neutralizing antibodies at least 200 days post-administration, comprising at least one antigen consisting of a ribosome inactivating protein and at least one antigen comprising a toxin derived from bacterial spores. Method making and using a stable immunogenic composition capable of eliciting a stable immune response yielding a measurable increase in neutralizing antibodies at least 200 days post-administration, comprising providing an immunogenic composition comprising at least one antigen comprising a ribosome inactivating protein and at least one antigen comprising a toxin derived from bacterial spores and administering the immunogenic composition to an individual.

The present invention provides methods to produce toxoid vaccines, such as ricin A chain vaccines, with reduced ability to promote vascular leak syndrome (VLS) and catalytic toxicity associated with various proteinaceous toxins, such as ribosome inactivating proteins. The invention also provides toxoids which have been mutated to lack amino acid sequences which induce VLS and toxic catalytic activity.

The invention provides application of cucurmosin in preparation of drugs. A ribosome-inactivating protein, namely the cucurmosin, can be separated from pumpkin flesh; and the protein well displays the good tumor resisting activity and can be used for preparing antineoplastic drugs. The cucurmosin can strikingly restrain gastric cancer cells SGC7901 and hepatoma cells HepG2 Bel7404, tiny lung cancer cells A549, breast cancer cells MCF-7 and melanoma cells B16 which are cultured in vitro, has little inhibitory action on normal liver cells and PBLC of a person and displays obvious selection, and can strikingly restrain animal transplanted tumors, such as cervical cancer U14, melanoma cells B16, lung cancer Lewis and the like. Furthermore, the application proves that the induction apoptosis and the induction differentiation of the cucurmosin on the tumor resisting activity serve as an important mechanism.

The present invention relates to the separation process, product and encoding gene of Gynostemma pentaphylla ribosome inactivating protein (RIP) and belongs to the field of biotechnology. A fast separation and purification system is established, which has the affinity chromatography with blue dye pseudoligand Cibacron Blue 3GA as main part, stepped ammonium sulfate precipitation and cation exchange chromatography. The RIP has molecular weight of 27 KDa and the 19 amino acid sequence of DINFSLAGADGQTYNTFIA. The RIP has homology of 10-37 % with the RIP of other plant and 37-73 % with the RIPof cucurbitaceous plant; tobacco mosaic virus resisting effect of 99 % and suppression to stomach cancer cell. The RIP has homology base level to RIP of cucurbitaceous plant 47-61 % and amino acid level 37-49 %, and has wide medicinal and agricultural application.