Chemistry:Rebeccamycin

From HandWiki

Rebeccamycin (NSC 655649) is a weak topoisomerase I inhibitor isolated from Nocardia bacteria.[1][2] It is structurally similar to staurosporine, but does not show any inhibitory activity against protein kinases. It shows significant antitumor properties in vitro (IC50=480nM against mouse B16 melanoma cells and IC50=500nM against P388 leukemia cells). It is an antineoplastic antibiotic and an intercalating agent.

Becatecarin (BMS-181176) is a synthetic analog of rebeccamycin.[3]

Rebeccamycin and becatecarin have been tested in phase II clinical trials for the treatment of lung cancer, liver cancer, breast cancer, lymphoma, retinoblastoma, kidney cancer, and ovarian cancer.[4]

Biosynthesis

An early step in the biosynthesis is the reaction of 7-chloro-L-tryptophan with oxygen catalysed by 7-chloro-L-tryptophan oxidase (RebO):[5][6]

Template:Chemrxn

Dichlorochromopyrrolate synthase (RebD) couples two molecules of the intermediate 2-iminio-3-(7-chloroindol-3-yl)propionate to give dichlorochromopyrrolic acid:[7]

Template:Chemrxn

The enzyme dichloroarcyriaflavin A synthase is responsible for forming the new aromatic bond between the indole components of dichlorochromopyrrolic acid, making a six-membered ring.[8]

Template:Chemrxn

The reaction proceeds in two stages. A protein component, called RebP, is an oxidase which contains heme and uses oxygen and nicotinamide adenine dinucleotide (NADH) to link the rings. Then it acts with a flavin-dependent partner called RebC to remove the two carboxylic acid groups by oxidative decarboxylation.[9]

The penultimate step in rebeccamycin's biosynthesis is the addition of a sugar group to one of the indole nitrogens by 4'-demethylrebeccamycin synthase (RebG).[7]

Template:Chemrxn

The final methylation is carried out by demethylrebeccamycin-D-glucose O-methyltransferase (RebM) using S-adenosyl methionine as cofactor.[7]

References

  1. "Isolation and structure of rebeccamycin-a new antitumor antibiotic from Nocardia aerocoligenes.". Tetrahedron Letters 26 (34): 4011–4014. January 1985. doi:10.1016/S0040-4039(00)89280-1. 
  2. "Production and biological activity of rebeccamycin, a novel antitumor agent". The Journal of Antibiotics 40 (5): 668–78. May 1987. doi:10.7164/antibiotics.40.668. PMID 3112080. 
  3. Clinical trial number NCT00006017 at ClinicalTrials.gov
  4. "2 Studies found for: BRN 4732638". Clinical Trials Gov. https://clinicaltrials.gov/ct2/results?term=BRN+4732638. 
  5. "Molecular analysis of the rebeccamycin L-amino acid oxidase from Lechevalieria aerocolonigenes ATCC 39243". Journal of Bacteriology 187 (6): 2084–92. March 2005. doi:10.1128/JB.187.6.2084-2092.2005. PMID 15743957. 
  6. "Enzymatic genеration of the chromopyrrolic acid scaffold of rebeccamycin by the tandem action of RebO and RebD". Biochemistry 44 (48): 15652–63. December 2005. doi:10.1021/bi051706e. PMID 16313168. 
  7. 7.0 7.1 7.2 Pommerehne, Kathrin; Walisko, Jana; Ebersbach, Anna; Krull, Rainer (2019). "The antitumor antibiotic rebeccamycin—challenges and advanced approaches in production processes". Applied Microbiology and Biotechnology 103 (9): 3627–3636. doi:10.1007/s00253-019-09741-y. PMID 30888461. 
  8. "Crystal structures and catalytic mechanism of cytochrome P450 StaP that produces the indolocarbazole skeleton". Proceedings of the National Academy of Sciences of the United States of America 104 (28): 11591–6. July 2007. doi:10.1073/pnas.0702946104. PMID 17606921. Bibcode2007PNAS..10411591M. 
  9. "Staurosporine and rebeccamycin aglycones are assembled by the oxidative action of StaP, StaC, and RebC on chromopyrrolic acid". Journal of the American Chemical Society 128 (37): 12289–98. September 2006. doi:10.1021/ja063898m. PMID 16967980. Bibcode2006JAChS.12812289H. 

Further reading

  • "Syntheses and biological activities (topoisomerase inhibition and antitumor and antimicrobial properties) of rebeccamycin analogues bearing modified sugar moieties and substituted on the imide nitrogen with a methyl group". Journal of Medicinal Chemistry 40 (21): 3456–65. October 1997. doi:10.1021/jm9702084. PMID 9341921. 
  • "DNA cleavage by topoisomerase I in the presence of indolocarbazole derivatives of rebeccamycin". Biochemistry 36 (13): 3917–29. April 1997. doi:10.1021/bi9624898. PMID 9092822. 
  • "Calories from carbohydrates: energetic contribution of the carbohydrate moiety of rebeccamycin to DNA binding and the effect of its orientation on topoisomerase I inhibition". Chemistry & Biology 6 (5): 277–86. May 1999. doi:10.1016/S1074-5521(99)80073-8. PMID 10322124.