title: Two novel cyclic hexapeptides from the genetically engineered Actinosynnema pretiosum.
abstract: Two novel cyclic hexapeptides designated actinosynneptides A (1) and B (2), together with three tryptophan containing diketopiperazines, namely cyclo(L-Trp-L-Trp) (3), cyclo(L-Trp-N-MeL-Trp) (4), and cyclo(N-MeL-Trp-N-MeL-Trp) (5), were isolated from the culture of the genetically engineered strain HGF052::asm18 derived from Actinosynnema pretiosum ATCC31565. Their structures were elucidated on the basis of spectroscopic analyses and single-crystal X-ray diffractions. Compound 1 is the first example of 3-amino-6-hydroxy-2-piperidone-containing cyclic peptides, and 1 and 2 showed moderate cytotoxic activities against HeLa and PC3 cell lines.
authors.affiliation: Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, Jinan, Shandong, 250012, People's Republic of China.
authors.forename: Chunhua
authors.initials: C
authors.lastname: Lu
authors.affiliation: Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, Jinan, Shandong, 250012, People's Republic of China.
authors.forename: Fei
authors.initials: F
authors.lastname: Xie
authors.affiliation: School of Chemistry and Chemical Engineering|, Shandong University, Jinan, Shandong, 250100, People's Republic of China.
authors.forename: Chuan
authors.initials: C
authors.lastname: Shan
authors.affiliation: Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, Jinan, Shandong, 250012, People's Republic of China. yshen@sdu.edu.cn.
authors.forename: Yuemao
authors.initials: Y
authors.lastname: Shen
mesh_terms: D000192:Actinomycetales / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D003603:Cytotoxins / Q000096:biosynthesis* / Q000737:chemistry / Q000494:pharmacology; D054659:Diketopiperazines / Q000737:chemistry / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D005285:Fermentation; D015964:Gene Expression Regulation, Bacterial; D005818:Genetic Engineering; D006367:HeLa Cells; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D010456:Peptides, Cyclic / Q000096:biosynthesis* / Q000737:chemistry / Q000494:pharmacology
chemical_list: D001426:Bacterial Proteins; D003603:Cytotoxins; D054659:Diketopiperazines; D010456:Peptides, Cyclic; C000614749:actinosynneptide A; C000614750:actinosynneptide B
keywords: Actinosynnema pretiosum; Cyclic hexapeptide; Diketopiperazine