TLN-05220, TLN-05223, new Echinosporamicin-type antibiotics, and proposed revision of the structure of bravomicins(*).
The deposited strain of the hazimicin producer, Micromonospora echinospora ssp. challisensis NRRL 12255 has considerable biosynthetic capabilities as revealed by genome scanning. Among these is a locus containing both type I and type II PKS genes. The presumed products of this locus, TLN-05220 (1) and TLN-05223 (2), bear a core backbone composed of six fused rings starting with a 2-pyridone moiety. The structures were confirmed by conventional spectral analyses including MS, and 1D and 2D NMR experiments. Comparison of both the 1H and 13C NMR data of the newly isolated compound with those of echinosporamicin and bravomicin A led us to propose a revision of the structure of the latter to include a 2-pyridone instead of the pyran originally postulated. Both compounds (1 and 2) possessed strong antibacterial activity against a series of gram-positive pathogens including several strains of methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococci (VRE), and cytotoxic activities against several human tumor cell lines. The TLN compounds are the first of this group with reported anticancer activity.
Banskota
Arjun H
AH
Institute for Marine Biosciences, National Research Council, Halifax, Nova Scotia, Canada.
Aouidate
Mustapha
M
Sørensen
Dan
D
Ibrahim
Ashraf
A
Piraee
Mahmood
M
Zazopoulos
Emmanuel
E
Alarco
Anne-Marie
AM
Gourdeau
Henriette
H
Mellon
Christophe
C
Farnet
Chris M
CM
Falardeau
Pierre
P
McAlpine
James B
JB
D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D000903:Antibiotics, Antineoplastic / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D002277:Carcinoma / Q000188:drug therapy*; D045744:Cell Line, Tumor; D016983:Enterococcus / Q000187:drug effects; D006094:Gram-Positive Bacteria / Q000187:drug effects*; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D013058:Mass Spectrometry; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects; D051379:Mice; D008819:Mice, Nude; D008826:Microbial Sensitivity Tests; D008847:Micromonospora / Q000145:classification / Q000254:growth & development / Q000378:metabolism*; D008969:Molecular Sequence Data; D011084:Polycyclic Aromatic Hydrocarbons / Q000737:chemistry* / Q000378:metabolism* / Q000494:pharmacology*; D011471:Prostatic Neoplasms / Q000188:drug therapy*; D013329:Structure-Activity Relationship; D020713:Vancomycin Resistance / Q000187:drug effects
D000900:Anti-Bacterial Agents; D000903:Antibiotics, Antineoplastic; D011084:Polycyclic Aromatic Hydrocarbons; C545190:TLN 05220; C545191:TLN 05223