If an enzyme name is shown in bold, there is experimental evidence for this enzymatic activity.
|Superclasses:||Biosynthesis → Secondary Metabolites Biosynthesis → Antibiotic Biosynthesis|
Some taxa known to possess this pathway include : Streptomyces coelicolor A3(2)
Expected Taxonomic Range:
The dimeric, benzoisochromanequinone antibiotic, actinorhodin, is an aromatic polyketide. Polyketides have been found to posses extensive biological activities and therefore, the actinorhodin pathway has undergone intensive genetic and biochemical studies for several years. The actinorhodin cluster is composed of 22 genes (SCO5071- SCO5092), which, in addition to the genes that encode catalytic enzymes, include genes that encode regulatory (SCO5082, SCO5085) and actinorhodin transport (SCO5083) proteins.
About This Pathway
Actinorhodin biosynthesis starts with 8 malonyl-CoAs and the minimal PKS, composed of a ketoacylsynthase, KSα, a chain-length factor, chain length factor, and an acyl carrier protein, actinorhodin polyketide synthase [acp]-like protein [McDaniel93]. The KSα and CLF form a heterodimer [FernandezMoreno92] and create a tunnel that stabilizes the growing polyketide backbone and controls chain length [Gualdi92][KeatingeClay04].
The first malonyl group is loaded onto the ACPPKS [Khosla92][Arthur06] by either the ACPPKS [Matharu98][Arthur05][Arthur06][Hitchman98] or a malonyltransferase from primary metabolism in a phenomenon termed 'cross talk' [Revill95][Khosla99] [Tang04][Carreras98]. Once loaded, it is decarboxylated to the starter acetyl group by the KSα [KeatingeClay04] and subsequently bound to KSα via a thioester bond. Once KSα is primed, a second malonyl group is transferred to ACPPKS and undergoes a KSα-catalyzed condensation with the acetyl starter group. 6 more malonyl groups are inidividually transferred to ACPPKS and condensed to the growing polyketide chain in the same manner [Sherman89][Bibb89][Meurer95][Arthur06]. The resultant chain is attached to the ACPPKS by a thioester bond.
As the chain grows into the KSα-CLF tunnel, it buckles, which is believed to initiate the first ring cyclization. Further molecular interactions complete formation of the first ring [KeatingeClay04].
Following first ring cyclization and with the carbon chain still attached to the ACPPKS, the C-9 keto-group is reduced to a hydroxyl group by ActIII [Hallam88][Bartel90] [Yu94][Teartasin04][Hadfield04][Sherman89][McDaniel93a][McDaniel93] [Fu94]. Subsequently, the first ring is aromatized by ActVII [McDaniel94] and then a second ring is formed by ActIV via an intramolecular aldol condensation [McDaniel94]. The compound is then released from ACPPKS as it was determined that a non-enzyme bound acid is the likely substrate for the next enzyme, ActVI-ORF1 [BookerMilburn05].
ActVI-ORF1 then reduces the keto-group at C-3 resulting in a chiral secondary alcohol [FernandezMoreno94] [Ichinose99][Taguchi00][Taguchi04]. A pyran ring is then formed with the assistance of ActVI-ORF3, followed by a spontaneous dehydration [FernandezMoreno94][Ichinose99] [Taguchi00]. The resulting compound, (S)-DNPA, was found to be the best trigger for actinorhodin export via a 'feed-forward' mechanism. (S)-DNPA, and to a lesser extent, actinorhodin itself, eliminates the interaction between the repressor, ActII-ORF1, and the operon, actII-ORF2-actII-ORF3 (SCO5083-SCO5084), allowing transcription of the operon. actII-ORF3 may encode an enzyme involved in the synthesis of a second actinorhodin pigment, γ-actinorhodin, while actII-ORF2 encodes the protein that exports both actinorhodins before their intracellular levels become toxic [Bystrykh96][Tahlan07].
In the next biosynthesis step, the double bond between C-14 and C-15 is reduced by ActVI-ORF2, while ActVI-ORF4 assists in formation of the chemically favored isomer [FernandezMoreno94] [Taguchi00]. ActVA-ORF6 then oxidizes the substrate to form a quinone [Sciara03][Kendrew00][Kendrew97], which is most likely dimerized at this point. Though this step has yet to be determined experimentally, basic chemistry favors dimerization before hydroxylation since the C-11 hydroxyl of the quinone substrate could easily direct coupling to the C-10 ortho position [Kendrew95].
Finally, the actinorhodin precursor is oxidized by a two-component NADH:flavin-dependent monooxygenase system, composed of ActVII and ActVA-ORF5. ActVB is the NADH:flavin reductase which reduces FMN in the presence of cofactor, NADH. ActVA-ORF5 then binds the reduced FMN along with molecular oxygen, forming an electrophillic flavin hydroperoxide intermediate. This intermediate then oxidizes the actinorhodin precursor, subsequently releasing an oxidized FMN which diffuses from ActVA-ORF5 to ActVB for another cycle [Valton06][Filisetti05][Valton04][Filisetti03][Kendrew95][Cole87].
Citations: [Shen93, Aceti98, Rudd79, He00, Wietzorrek97, Fu94a, Parro91, Leavitt94, Kang97, Sherman92, Taguchi07, Kim95a, Hillen82, Arias99, Bisang99, Crump96, FernandezMoreno91, Gramajo93, Ichinose98, Fu94b, Hopwood04, Caballero91, Omura86, McDaniel94a, Caballero91a, Tang03, Crump97, Malpartida, Malpartida86, Hopwood, Zhang90, Hesketh03, Kanehisa05, Kanehisa05a, Ichinose01, Hopwood07, Summers95]
Aceti98: Aceti DJ, Champness WC (1998). "Transcriptional regulation of Streptomyces coelicolor pathway-specific antibiotic regulators by the absA and absB loci." J Bacteriol 180(12);3100-6. PMID: 9620958
Arias99: Arias P, Fernandez-Moreno MA, Malpartida F (1999). "Characterization of the pathway-specific positive transcriptional regulator for actinorhodin biosynthesis in Streptomyces coelicolor A3(2) as a DNA-binding protein." J Bacteriol 181(22);6958-68. PMID: 10559161
Arthur05: Arthur CJ, Szafranska A, Evans SE, Findlow SC, Burston SG, Owen P, Clark-Lewis I, Simpson TJ, Crosby J, Crump MP (2005). "Self-malonylation is an intrinsic property of a chemically synthesized type II polyketide synthase acyl carrier protein." Biochemistry 44(46);15414-21. PMID: 16285746
Arthur06: Arthur CJ, Szafranska AE, Long J, Mills J, Cox RJ, Findlow SC, Simpson TJ, Crump MP, Crosby J (2006). "The malonyl transferase activity of type II polyketide synthase acyl carrier proteins." Chem Biol 13(6);587-96. PMID: 16793516
Bartel90: Bartel PL, Zhu CB, Lampel JS, Dosch DC, Connors NC, Strohl WR, Beale JM, Floss HG (1990). "Biosynthesis of anthraquinones by interspecies cloning of actinorhodin biosynthesis genes in streptomycetes: clarification of actinorhodin gene functions." J Bacteriol 172(9);4816-26. PMID: 2394677
Bibb89: Bibb MJ, Biro S, Motamedi H, Collins JF, Hutchinson CR (1989). "Analysis of the nucleotide sequence of the Streptomyces glaucescens tcmI genes provides key information about the enzymology of polyketide antibiotic biosynthesis." EMBO J 8(9);2727-36. PMID: 2684656
Bisang99: Bisang C, Long PF, Cortes J, Westcott J, Crosby J, Matharu AL, Cox RJ, Simpson TJ, Staunton J, Leadlay PF (1999). "A chain initiation factor common to both modular and aromatic polyketide synthases." Nature 401(6752);502-5. PMID: 10519556
BookerMilburn05: Booker-Milburn KI, Gillan R, Kimberley M, Taguchi T, Ichinose K, Stephenson GR, Ebizuka Y, Hopwood DA (2005). "Enantioselective reduction of beta-keto acids with engineered Streptomyces coelicolor." Angew Chem Int Ed Engl 44(7);1121-5. PMID: 15645472
Bystrykh96: Bystrykh LV, Fernandez-Moreno MA, Herrema JK, Malpartida F, Hopwood DA, Dijkhuizen L (1996). "Production of actinorhodin-related "blue pigments" by Streptomyces coelicolor A3(2)." J Bacteriol 178(8);2238-44. PMID: 8636024
Caballero91: Caballero JL, Martinez E, Malpartida F, Hopwood DA (1991). "Organisation and functions of the actVA region of the actinorhodin biosynthetic gene cluster of Streptomyces coelicolor." Mol Gen Genet 230(3);401-12. PMID: 1766437
Caballero91a: Caballero JL, Malpartida F, Hopwood DA (1991). "Transcriptional organization and regulation of an antibiotic export complex in the producing Streptomyces culture." Mol Gen Genet 228(3);372-80. PMID: 1716725
Cole87: Cole SP, Rudd BA, Hopwood DA, Chang CJ, Floss HG (1987). "Biosynthesis of the antibiotic actinorhodin. Analysis of blocked mutants of Streptomyces coelicolor." J Antibiot (Tokyo) 40(3);340-7. PMID: 3570987
Crump96: Crump MP, Crosby J, Dempsey CE, Murray M, Hopwood DA, Simpson TJ (1996). "Conserved secondary structure in the actinorhodin polyketide synthase acyl carrier protein from Streptomyces coelicolor A3(2) and the fatty acid synthase acyl carrier protein from Escherichia coli." FEBS Lett 391(3);302-6. PMID: 8764994
Crump97: Crump MP, Crosby J, Dempsey CE, Parkinson JA, Murray M, Hopwood DA, Simpson TJ (1997). "Solution structure of the actinorhodin polyketide synthase acyl carrier protein from Streptomyces coelicolor A3(2)." Biochemistry 36(20);6000-8. PMID: 9166770
FernandezMoreno91: Fernandez-Moreno MA, Caballero JL, Hopwood DA, Malpartida F (1991). "The act cluster contains regulatory and antibiotic export genes, direct targets for translational control by the bldA tRNA gene of Streptomyces." Cell 66(4);769-80. PMID: 1878971
FernandezMoreno92: Fernandez-Moreno MA, Martinez E, Boto L, Hopwood DA, Malpartida F (1992). "Nucleotide sequence and deduced functions of a set of cotranscribed genes of Streptomyces coelicolor A3(2) including the polyketide synthase for the antibiotic actinorhodin." J Biol Chem 267(27);19278-90. PMID: 1527048
FernandezMoreno94: Fernandez-Moreno MA, Martinez E, Caballero JL, Ichinose K, Hopwood DA, Malpartida F (1994). "DNA sequence and functions of the actVI region of the actinorhodin biosynthetic gene cluster of Streptomyces coelicolor A3(2)." J Biol Chem 269(40);24854-63. PMID: 7929165
Filisetti05: Filisetti L, Valton J, Fontecave M, Niviere V (2005). "The flavin reductase ActVB from Streptomyces coelicolor: characterization of the electron transferase activity of the flavoprotein form." FEBS Lett 579(13);2817-20. PMID: 15878552
Fu94: Fu, H., Ebert-Khosla, S., Hopwood, D.A., Khosla, C. (1994). "Engineered Biosynthesis of Novel Polyketides: Dissection of the Catalytic Specificity of the act Ketoreductase." J. Am. Chem. Soc. 116, 4166-4170.
Fu94a: Fu H, McDaniel R, Hopwood DA, Khosla C (1994). "Engineered biosynthesis of novel polyketides: stereochemical course of two reactions catalyzed by a polyketide synthase." Biochemistry 33(31);9321-6. PMID: 8049233
Fu94b: Fu H, Hopwood DA, Khosla C (1994). "Engineered biosynthesis of novel polyketides: evidence for temporal, but not regiospecific, control of cyclization of an aromatic polyketide precursor." Chem Biol 1(4);205-10. PMID: 9383392
Gramajo93: Gramajo HC, Takano E, Bibb MJ (1993). "Stationary-phase production of the antibiotic actinorhodin in Streptomyces coelicolor A3(2) is transcriptionally regulated." Mol Microbiol 7(6);837-45. PMID: 7683365
Gualdi92: Gualdi GF, Ceroni L, Polettini E, D'Agostino A (1992). "[Role of magnetic resonance in the evaluation of thrombosis of large thoraco-abdominal vessels]." Clin Ter 141(9);219-26. PMID: 1458809
Hadfield04: Hadfield AT, Limpkin C, Teartasin W, Simpson TJ, Crosby J, Crump MP (2004). "The crystal structure of the actIII actinorhodin polyketide reductase: proposed mechanism for ACP and polyketide binding." Structure 12(10);1865-75. PMID: 15458634
Hallam88: Hallam SE, Malpartida F, Hopwood DA (1988). "Nucleotide sequence, transcription and deduced function of a gene involved in polyketide antibiotic synthesis in Streptomyces coelicolor." Gene 74(2);305-20. PMID: 2469622
He00: He M, Varoglu M, Sherman DH (2000). "Structural modeling and site-directed mutagenesis of the actinorhodin beta-ketoacyl-acyl carrier protein synthase." J Bacteriol 182(9);2619-23. PMID: 10762267
Hesketh03: Hesketh A, Chater KF (2003). "Evidence from proteomics that some of the enzymes of actinorhodin biosynthesis have more than one form and may occupy distinctive cellular locations." J Ind Microbiol Biotechnol 30(8);523-9. PMID: 12856192
Hillen82: Hillen W, Klock G, Kaffenberger I, Wray LV, Reznikoff WS (1982). "Purification of the TET repressor and TET operator from the transposon Tn10 and characterization of their interaction." J Biol Chem 257(11);6605-13. PMID: 6281280
Hopwood07: Hopwood, D.A. (2007). "How Do Antibiotic-Producing Bacteria Ensure Their Self-Resistance Before Antibiotic Biosynthesis Incapacitates Them?." Mol. Microbiol., Postprint, doi: 10.1111/j.1365-2958.2006.05584.x.
Ichinose01: Ichinose K, Taguchi T, Bedford DJ, Ebizuka Y, Hopwood DA (2001). "Functional complementation of pyran ring formation in actinorhodin biosynthesis in Streptomyces coelicolor A3(2) by ketoreductase genes for granaticin biosynthesis." J Bacteriol 183(10);3247-50. PMID: 11325954
Ichinose98: Ichinose K, Bedford DJ, Tornus D, Bechthold A, Bibb MJ, Revill WP, Floss HG, Hopwood DA (1998). "The granaticin biosynthetic gene cluster of Streptomyces violaceoruber Tu22: sequence analysis and expression in a heterologous host." Chem Biol 5(11);647-59. PMID: 9831526
Ichinose99: Ichinose K, Surti C, Taguchi T, Malpartida F, Booker-Milburn KI, Stephenson GR, Ebizuka Y, Hopwood DA (1999). "Proof that the ACTVI genetic region of Streptomyces coelicolor A3(2) is involved in stereospecific pyran ring formation in the biosynthesis of actinorhodin." Bioorg Med Chem Lett 9(3);395-400. PMID: 10091691
Kang97: Kang JG, Hahn MY, Ishihama A, Roe JH (1997). "Identification of sigma factors for growth phase-related promoter selectivity of RNA polymerases from Streptomyces coelicolor A3(2)." Nucleic Acids Res 25(13);2566-73. PMID: 9185565
Kendrew00: Kendrew SG, Federici L, Savino C, Miele A, Marsh EN, Vallone B (2000). "Crystallization and preliminary X-ray diffraction studies of a monooxygenase from Streptomyces coelicolor A3(2) involved in the biosynthesis of the polyketide actinorhodin." Acta Crystallogr D Biol Crystallogr 56(Pt 4);481-3. PMID: 10739927
Kendrew95: Kendrew SG, Harding SE, Hopwood DA, Marsh EN (1995). "Identification of a flavin:NADH oxidoreductase involved in the biosynthesis of actinorhodin. Purification and characterization of the recombinant enzyme." J Biol Chem 270(29);17339-43. PMID: 7615536
Kendrew97: Kendrew SG, Hopwood DA, Marsh EN (1997). "Identification of a monooxygenase from Streptomyces coelicolor A3(2) involved in biosynthesis of actinorhodin: purification and characterization of the recombinant enzyme." J Bacteriol 179(13);4305-10. PMID: 9209048
Khosla92: Khosla C, Ebert-Khosla S, Hopwood DA (1992). "Targeted gene replacements in a Streptomyces polyketide synthase gene cluster: role for the acyl carrier protein." Mol Microbiol 6(21);3237-49. PMID: 1453961
Kim95a: Kim ES, Cramer KD, Shreve AL, Sherman DH (1995). "Heterologous expression of an engineered biosynthetic pathway: functional dissection of type II polyketide synthase components in Streptomyces species." J Bacteriol 177(5);1202-7. PMID: 7868592
Malpartida: Malpartida F, Hallam SE, Kieser HM, Motamedi H, Hutchinson CR, Butler MJ, Sugden DA, Warren M, McKillop C, Bailey CR "Homology between Streptomyces genes coding for synthesis of different polyketides used to clone antibiotic biosynthetic genes." Nature 325(6107);818-21. PMID: 3029594
Malpartida86: Malpartida F, Hopwood DA (1986). "Physical and genetic characterisation of the gene cluster for the antibiotic actinorhodin in Streptomyces coelicolor A3(2)." Mol Gen Genet 205(1);66-73. PMID: 3025560
Matharu98: Matharu AL, Cox RJ, Crosby J, Byrom KJ, Simpson TJ (1998). "MCAT is not required for in vitro polyketide synthesis in a minimal actinorhodin polyketide synthase from Streptomyces coelicolor." Chem Biol 5(12);699-711. PMID: 9862793
McDaniel93a: McDaniel, R., Ebert-Kosla, S., Hopwood, D.A., Khosla, C. (1993). "Engineerred Biosynthesis of Novel Polyketides: Manipulation and Analysis of an Aromatic Polyketide Synthase with Unproven Catalytic Specificities." J. Am. Chem. Soc., 115, 11671-11675.
McDaniel94: McDaniel, R., Ebert-Khosla, S., Hopwood, D.A., Khosla, C. (1994). "Engineered Biosynthesis of Novel Polyketides: actVII and actIV Genes Encode Aromatase and Cyclase Enzymes, Respectively." J. Am. Chem. Soc. 116(24): 10855-10859.
McDaniel94a: McDaniel R, Ebert-Khosla S, Fu H, Hopwood DA, Khosla C (1994). "Engineered biosynthesis of novel polyketides: influence of a downstream enzyme on the catalytic specificity of a minimal aromatic polyketide synthase." Proc Natl Acad Sci U S A 91(24);11542-6. PMID: 7972098
Meurer95: Meurer G, Hutchinson CR (1995). "Functional analysis of putative beta-ketoacyl:acyl carrier protein synthase and acyltransferase active site motifs in a type II polyketide synthase of Streptomyces glaucescens." J Bacteriol 177(2);477-81. PMID: 7814341
Omura86: Omura S, Ikeda H, Malpartida F, Kieser HM, Hopwood DA (1986). "Production of new hybrid antibiotics, mederrhodins A and B, by a genetically engineered strain." Antimicrob Agents Chemother 29(1);13-9. PMID: 3460518
Parro91: Parro V, Hopwood DA, Malpartida F, Mellado RP (1991). "Transcription of genes involved in the earliest steps of actinorhodin biosynthesis in Streptomyces coelicolor." Nucleic Acids Res 19(10);2623-7. PMID: 2041740
Revill95: Revill WP, Bibb MJ, Hopwood DA (1995). "Purification of a malonyltransferase from Streptomyces coelicolor A3(2) and analysis of its genetic determinant." J Bacteriol 177(14);3946-52. PMID: 7608065
Sciara03: Sciara G, Kendrew SG, Miele AE, Marsh NG, Federici L, Malatesta F, Schimperna G, Savino C, Vallone B (2003). "The structure of ActVA-Orf6, a novel type of monooxygenase involved in actinorhodin biosynthesis." EMBO J 22(2);205-15. PMID: 12514126
Shen93: Shen B, Hutchinson CR (1993). "Tetracenomycin F1 monooxygenase: oxidation of a naphthacenone to a naphthacenequinone in the biosynthesis of tetracenomycin C in Streptomyces glaucescens." Biochemistry 32(26);6656-63. PMID: 8329392
Sherman89: Sherman DH, Malpartida F, Bibb MJ, Kieser HM, Bibb MJ, Hopwood DA (1989). "Structure and deduced function of the granaticin-producing polyketide synthase gene cluster of Streptomyces violaceoruber Tu22." EMBO J 8(9);2717-25. PMID: 2583128
Sherman92: Sherman DH, Kim ES, Bibb MJ, Hopwood DA (1992). "Functional replacement of genes for individual polyketide synthase components in Streptomyces coelicolor A3(2) by heterologous genes from a different polyketide pathway." J Bacteriol 174(19);6184-90. PMID: 1400167
Summers95: Summers RG, Ali A, Shen B, Wessel WA, Hutchinson CR (1995). "Malonyl-coenzyme A:acyl carrier protein acyltransferase of Streptomyces glaucescens: a possible link between fatty acid and polyketide biosynthesis." Biochemistry 34(29);9389-402. PMID: 7626609
Taguchi00: Taguchi T, Itou K, Ebizuka Y, Malpartida F, Hopwood DA, Surti CM, Booker-Milburn KI, Stephenson GR, Ichinose K (2000). "Chemical characterisation of disruptants of the Streptomyces coelicolor A3(2) actVI genes involved in actinorhodin biosynthesis." J Antibiot (Tokyo) 53(2);144-52. PMID: 10805574
Taguchi04: Taguchi T, Kunieda K, Takeda-Shitaka M, Takaya D, Kawano N, Kimberley MR, Booker-Milburn KI, Stephenson GR, Umeyama H, Ebizuka Y, Ichinose K (2004). "Remarkably different structures and reaction mechanisms of ketoreductases for the opposite stereochemical control in the biosynthesis of BIQ antibiotics." Bioorg Med Chem 12(22);5917-27. PMID: 15498668
Taguchi07: Taguchi, T., et al. (2007). "Possible Involvement of ActVI-ORFA in Transcriptional Regulation of actVI Tailoring-Step Genes for Actinorhodin Biosynthesis." FEMS Microbiol. Lett., Online Early.
Teartasin04: Teartasin W, Limpkin C, Glod F, Spencer J, Cox RJ, Simpson TJ, Crosby J, Crump MP, Hadfield AT (2004). "Expression, purification and preliminary X-ray diffraction analysis of a ketoreductase from a type II polyketide synthase." Acta Crystallogr D Biol Crystallogr 60(Pt 6);1137-8. PMID: 15159580
Valton04: Valton J, Filisetti L, Fontecave M, Niviere V (2004). "A two-component flavin-dependent monooxygenase involved in actinorhodin biosynthesis in Streptomyces coelicolor." J Biol Chem 279(43);44362-9. PMID: 15297451
Valton06: Valton J, Fontecave M, Douki T, Kendrew SG, Niviere V (2006). "An aromatic hydroxylation reaction catalyzed by a two-component FMN-dependent Monooxygenase. The ActVA-ActVB system from Streptomyces coelicolor." J Biol Chem 281(1);27-35. PMID: 16267053
Wietzorrek97: Wietzorrek A, Bibb M (1997). "A novel family of proteins that regulates antibiotic production in streptomycetes appears to contain an OmpR-like DNA-binding fold." Mol Microbiol 25(6);1181-4. PMID: 9350875
Yu94: Yu TW, Bibb MJ, Revill WP, Hopwood DA (1994). "Cloning, sequencing, and analysis of the griseusin polyketide synthase gene cluster from Streptomyces griseus." J Bacteriol 176(9);2627-34. PMID: 8169211
Huang92: Huang CJ, Fwu ML (1992). "Protein insufficiency aggravates the enhanced lipid peroxidation and reduced activities of antioxidative enzymes in rats fed diets high in polyunsaturated fat." J Nutr 122(5);1182-9. PMID: 1564572
Kim94: Kim ES, Hopwood DA, Sherman DH (1994). "Analysis of type II polyketide beta-ketoacyl synthase specificity in Streptomyces coelicolor A3(2) by trans complementation of actinorhodin synthase mutants." J Bacteriol 176(6);1801-4. PMID: 8132481
Rubio06: Rubio S, Larson TR, Gonzalez-Guzman M, Alejandro S, Graham IA, Serrano R, Rodriguez PL (2006). "An Arabidopsis mutant impaired in coenzyme A biosynthesis is sugar dependent for seedling establishment." Plant Physiol 140(3);830-43. PMID: 16415216
©2015 SRI International, 333 Ravenswood Avenue, Menlo Park, CA 94025-3493