FIELD: biotechnology, genetic engineering. SUBSTANCE: invention relates to recombinant polypeptide inhibiting adhesion and aggregation of platelets under pathological conditions (cerebrovascular and cardiovascular disorders). Recombinant polypeptide has binding region GPIb of human von Willebrand factor and definite amino acid sequence. Method of platelet aggregation inhibition is carried out by contact of platelets with effective amount of recombinant polypeptide. For expression of recombinant polypeptide the recombinant plasmid DNA pvWF-VC3 or pvWF-VCL is used. Each of DNA has a binding region of glycoprotein Ib of human von Willebrand factor. This region involves DNA-fragment encoding polypeptide amino acid sequence and has promoter system deo P1P2 or promoter Pλ of lambda phage, deo-site of ribosome binding, T1T2-terminator of transcription and gene showing resistance to ampicillin AmpR as a genetic marker. Producers of polypeptide - strain E. coli/pvWF-VC3 or /pvWF-VCL. For polypeptide preparing strain E. coli is transformed with recombinant plasmid DNA followed by selection and culturing transformants under conditions providing polypeptide accumulation. For isolation biologically active polypeptide bacterial cells are disrupted and lysate is obtained. From lysate inclusion bodies are isolated using denaturating agent or guanidine hydrochloride, or urea followed by purification of polypeptide solution by cation-exchange chromatography. Dissolved polypeptide is treated with disulfide or glutathione, or thioredoxin, or beta-mercaptoethanol, or cysteine. Prepared polypeptide is dialyzed and dialysate is subjected for cation-exchange chromatography. EFFECT: improved method of preparing. 7 cl, 4 tbl, 27 dwg
