title: A New Analogue of Echinomycin and a New Cyclic Dipeptide from a Marine-Derived Streptomyces sp. LS298.
abstract: Quinomycin G (1), a new analogue of echinomycin, together with a new cyclic dipeptide, cyclo-(l-Pro-4-OH-l-Leu) (2), as well as three known antibiotic compounds tirandamycin A (3), tirandamycin B (4) and staurosporine (5), were isolated from Streptomyces sp. LS298 obtained from a marine sponge Gelliodes carnosa. The planar and absolute configurations of compounds 1 and 2 were established by MS, NMR spectral data analysis and Marfey's method. Furthermore, the differences in NMR data of keto-enol tautomers in tirandamycins were discussed for the first time. Antibacterial and anti-tumor activities of compound 1 were measured against 15 drug-sensitive/resistant strains and 12 tumor cell lines. Compound 1 exhibited moderate antibacterial activities against Staphylococcuse pidermidis, S. aureus, Enterococcus faecium, and E. faecalis with the minimum inhibitory concentration (MIC) values ranged from 16 to 64 μg/mL. Moreover, it displayed remarkable anti-tumor activities; the highest activity was observed against the Jurkat cell line (human T-cell leukemia) with an IC50 value of 0.414 μM.
authors.affiliation: State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, 1 Xian Nong Tan Street, Xicheng District, Beijing 100050, China. zhenxin@imm.ac.cn.
authors.forename: Xin
authors.initials: X
authors.lastname: Zhen
authors.affiliation: State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, 1 Xian Nong Tan Street, Xicheng District, Beijing 100050, China. gongting@imm.ac.cn.
authors.forename: Ting
authors.initials: T
authors.lastname: Gong
authors.affiliation: State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, 1 Xian Nong Tan Street, Xicheng District, Beijing 100050, China. liufu@imm.ac.cn.
authors.forename: Fu
authors.initials: F
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, 1 Xian Nong Tan Street, Xicheng District, Beijing 100050, China. pczhang@imm.ac.cn.
authors.forename: Pei-Cheng
authors.initials: PC
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, 1 Xian Nong Tan Street, Xicheng District, Beijing 100050, China. zhouwanqi@imm.ac.cn.
authors.forename: Wan-Qi
authors.initials: WQ
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, 1 Xian Nong Tan Street, Xicheng District, Beijing 100050, China. liyanxiao@imm.ac.cn.
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.affiliation: State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, 1 Xian Nong Tan Street, Xicheng District, Beijing 100050, China. zhuping@imm.ac.cn.
authors.forename: Ping
authors.initials: P
authors.lastname: Zhu
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects; D045744:Cell Line, Tumor; D004151:Dipeptides / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial; D004448:Echinomycin / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000302:isolation & purification / Q000494:pharmacology; D006801:Humans; D020128:Inhibitory Concentration 50; D019169:Jurkat Cells; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008826:Microbial Sensitivity Tests; D011161:Porifera / Q000382:microbiology; D013302:Streptomyces / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D000970:Antineoplastic Agents; D004151:Dipeptides; C010777:quinomycin; D004448:Echinomycin
keywords: anti-tumor activity; antibacterial activity; marine-derived Streptomyces; secondary metabolites