title: Smilaxin, a novel protein with immunostimulatory, antiproliferative, and HIV-1-reverse transcriptase inhibitory activities from fresh Smilax glabra rhizomes.
abstract: A protein, with a novel N-terminal amino acid sequence and a molecular mass of 30 kDa, was purified from fresh Smilax glabra rhizomes by adsorption on DEAE-cellulose, CM-cellulose, Con A-Sepharose, and Mono S, and by fast protein liquid chromatography-gel filtration on Superdex 75. The protein, designated as smilaxin, stimulated uptake of [methyl-3H]thymidine by murine splenocytes, peritoneal macrophages, and bone marrow cells, and production of nitric oxide by peritoneal macrophages. It inhibited uptake of [methyl-3H]thymidine by MBL2 and PU5 tumor cells but not uptake by S180 and L1210 cells. Smilaxin augmented glucose uptake into rat adipose tissue. It attenuated the activity of HIV-1-reverse transcriptase with an IC50 of 5.6 microM. However, it did not display hemagglutinating, antifungal or translation-inhibitory activities, indicating that it is not a lectin, an antifungal protein, or a ribosome-inactivating protein.
authors.affiliation: Department of Biochemistry, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, China.
authors.forename: K T
authors.initials: KT
authors.lastname: Chu
authors.forename: T B
authors.initials: TB
authors.lastname: Ng
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents; D001854:Bone Marrow Cells / Q000187:drug effects*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D054303:HIV Reverse Transcriptase / Q000037:antagonists & inhibitors*; D006801:Humans; D007155:Immunologic Factors / Q000008:administration & dosage*; D008297:Male; D051379:Mice; D009369:Neoplasms / Q000473:pathology*; D010936:Plant Extracts / Q000008:administration & dosage; D010940:Plant Proteins / Q000008:administration & dosage* / Q000032:analysis / Q000737:chemistry*; D018517:Plant Roots / Q000378:metabolism; D051381:Rats; D032281:Smilax / Q000378:metabolism*; D013154:Spleen / Q000187:drug effects*
chemical_list: D000970:Antineoplastic Agents; D007155:Immunologic Factors; D010936:Plant Extracts; D010940:Plant Proteins; C508102:smilaxin protein, Smilax glabra; D054303:HIV Reverse Transcriptase