title: GE3, a novel hexadepsipeptide antitumor antibiotic, produced by Streptomyces sp. I. Taxonomy, production, isolation, physico-chemical properties, and biological activities.
abstract: GE3, a novel cyclic hexadepsipeptide antibiotic, was isolated from the culture broth of Streptomyces sp. GE3. GE3 was weakly active against some Gram-positive and Gram-negative bacteria and showed potent cytotoxicity against human tumor cell lines. GE3 also exhibited antitumor activity against human pancreatic carcinoma, PSN-1, in vivo. GE3B, a linear peptide form of GE3, which was isolated from the same culture broth with GE3, showed no antibiotic and cytotoxic activities, suggesting the necessity of the cyclic structure of GE3 for its biological activities.
authors.affiliation: Tokyo Research Laboratories, Kyowa Hakko Kogyo Co., Ltd., Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Sakai
authors.forename: T
authors.initials: T
authors.lastname: Yoshida
authors.forename: T
authors.initials: T
authors.lastname: Tsujita
authors.forename: K
authors.initials: K
authors.lastname: Ochiai
authors.forename: T
authors.initials: T
authors.lastname: Agatsuma
authors.forename: Y
authors.initials: Y
authors.lastname: Saitoh
authors.forename: F
authors.initials: F
authors.lastname: Tanaka
authors.forename: T
authors.initials: T
authors.lastname: Akiyama
authors.forename: S
authors.initials: S
authors.lastname: Akinaga
authors.forename: T
authors.initials: T
authors.lastname: Mizukami
mesh_terms: D000818:Animals; D000903:Antibiotics, Antineoplastic / Q000737:chemistry / Q000302:isolation & purification* / Q000627:therapeutic use*; D047630:Depsipeptides; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D009368:Neoplasm Transplantation; D010190:Pancreatic Neoplasms / Q000188:drug therapy*; D010456:Peptides, Cyclic / Q000737:chemistry / Q000302:isolation & purification* / Q000627:therapeutic use*; D013302:Streptomyces; D013329:Structure-Activity Relationship; D014407:Tumor Cells, Cultured / Q000187:drug effects
chemical_list: D000903:Antibiotics, Antineoplastic; D047630:Depsipeptides; C108551:GE3 compound; C108552:GE3B compound; D010456:Peptides, Cyclic