• 제목/요약/키워드: labeling of small peptide

검색결과 2건 처리시간 0.016초

Expression and Purification of Delta Sleep-Inducing Peptide in Escherichia coli

  • Oh, Kwang-Seok;Na, Do-Kyung;Kweon, Mee-Hyang;Sung, Ha-Chin
    • Journal of Microbiology and Biotechnology
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    • 제13권4호
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    • pp.620-623
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    • 2003
  • The delta sleep-inducing peptides (DSIP, Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu) is an important regulatory hormone, controlling hypothalamus and pituitary functions. In the current study, an expression system was designed for the rapid and economic expression oi recombinant DSIP for biophysical studies. Artificially synthesized oligonucleotides encoding DSIP were cloned into a pGEX-KG vector and expressed in E. coli (BL21). The recombinant GST-DSIP was then readily purified using a GST affinity column. To obtain intact DSIP from the GST-DSIP, thrombin cleavage and a CNBr reaction were successively carried out. The DSIP in the CNBr reaction mixture was subjected to RP-HPLC purification to yield 1.2 mg DSIP from a 1 liter culture of E. coli. Identification of the DSIP was peformed using MALDI-MS and an amino acid composition analysis.

암세포 내로의 약물 전달 증진 목적의 신규 소마토스타틴 수용체 타겟리간드 합성 및 평가 (Synthesis and Evaluation of a Ligand Targeting the Somatostatin Receptor for Drug Delivery to Tumor Cell)

  • 최선주;홍영돈;이소영;정성희
    • 방사선산업학회지
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    • 제9권4호
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    • pp.193-198
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    • 2015
  • Most of targeted therapies block the action of certain enzymes, proteins, or other molecules involved in the growth and spread of cancer cells to produce its cytotoxic effect. Either small molecule drugs or monoclonal antibodies are mostly used in targeted therapies. Unfortunately, targeted therapy has a certain degree of unwanted side effect like other cytotoxicity inducing chemotherapies. To overcome and to reduce unwanted side effects during a cancer therapy, recently radiopeptide therapies has got the worlds' attraction for the tumor targeting modalities due to its beneficial effect on less side effect compared to cytotoxic chemotherapies. Among radiopeptide therapies, $^{177}Lu$-DOTATATE is a major modality as an effective one invented so far in treating neuroendocrine tumor (NET) and it has been in clinical trials at least one decade. Although it does have rather effective therapeutic effect on NET, it has less effective in rather large solid tumor. There are many ways to improve or increase therapeutic effect of radiopeptide are a finding the potent small molecules to target the tumor site selectively, or a labeling with radioisotope of emitting high energy, or an improving its biological half-life by introducing different moieties to increase lipophilicity. Present study was focus to increase a biological half-life of radio somatostatin which will target the somatostatin receptor by altering the bifunctional chelator (BFCA) by introducing lipophilic moiety to the somatostatin, which would make the labeled peptide stay longer in the tumor site and thus it can intensify the therapeutic effect on tumor cell itself and around tissues.