title: Novel GRP78 molecular chaperone expression down-regulators JBIR-04 and -05 isolated from Streptomyces violaceoniger.
abstract: In the course of our screening program for regulators of the expression of GRP78 molecular chaperone, JBIR-04 (1) and -05 (2) were isolated from Streptomyces violaceoniger 4541-SVS3 as congeners of prunustatin A (3). The structures of 1 and 2 were determined by the analyses of the spectroscopic data. These compounds mainly consist of an amino acid and amino acid derived alpha-hydroxy acid residues. 1 and 2 inhibited the expression of GRP78 induced by 2-deoxyglucose in human fibrosarcoma HT1080 cells, but their activities were highly reduced compared with those of 3 and SW-163A.
authors.affiliation: Japan Biological Information Research Center (JBIRC), Japan Biological Informatics Consortium (JBIC), Tokyo, Japan.
authors.forename: Miho
authors.initials: M
authors.lastname: Izumikawa
authors.forename: Jun-ya
authors.initials: JY
authors.lastname: Ueda
authors.forename: Shuhei
authors.initials: S
authors.lastname: Chijiwa
authors.forename: Motoki
authors.initials: M
authors.lastname: Takagi
authors.forename: Kazuo
authors.initials: K
authors.lastname: Shin-ya
mesh_terms: D045744:Cell Line, Tumor; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D015536:Down-Regulation / Q000187:drug effects; D000091342:Endoplasmic Reticulum Chaperone BiP; D006360:Heat-Shock Proteins / Q000096:biosynthesis*; D006801:Humans; D007202:Indicators and Reagents; D018942:Macrolides / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D018832:Molecular Chaperones / Q000096:biosynthesis*; D008968:Molecular Conformation; D010456:Peptides, Cyclic / Q000302:isolation & purification / Q000494:pharmacology*; D021241:Spectrometry, Mass, Electrospray Ionization; D013055:Spectrophotometry, Infrared; D013056:Spectrophotometry, Ultraviolet; D013302:Streptomyces / Q000737:chemistry*
chemical_list: D000091342:Endoplasmic Reticulum Chaperone BiP; C000717247:HSPA5 protein, human; D006360:Heat-Shock Proteins; D007202:Indicators and Reagents; C526002:JBIR-04; C526000:JBIR-05; D018942:Macrolides; D018832:Molecular Chaperones; D010456:Peptides, Cyclic; C501241:prunustatin A