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Thomsen E, Reitz ZL, Stow PR, Dulaney K, Butler A. Ruckerbactin Produced by Yersinia ruckeri YRB Is a Diastereomer of the Siderophore Trivanchrobactin Produced by Vibrio campbellii DS40M4. JOURNAL OF NATURAL PRODUCTS 2022; 85:264-269. [PMID: 34942075 DOI: 10.1021/acs.jnatprod.1c01047] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The Gram-negative bacterium Yersinia ruckeri is the causative agent for enteric red mouth disease in salmonids. The genome of Y. ruckeri YRB contains a biosynthetic gene cluster encoding the biosynthesis of catechol siderophores that are diastereomeric with the known vanchrobactin class of siderophores, (DHBDArgLSer)(1-3). Ruckerbactin (1), produced by Y. ruckeri YRB, was found to be the linear tris-l-serine ester composed of l-arginine and 2,3-dihydroxybenzoic acid, (DHBLArgLSer)3. The biscatechol, (DHBLArgLSer)2 (2), and monocatechol, DHBLArgLSer (3), compounds were also isolated and characterized. The macrolactone of ruckerbactin was not detected. The presence of LArg in ruckerbactin makes it the diastereomer of trivanchrobactin with DArg. The electronic circular dichroism spectra of Fe(III)-ruckerbactin and Fe(III)-trivanchrobactin reveal the opposite enantiomeric configurations at the Fe(III) sites. Fe(III)-ruckerbactin adopts the Δ configuration, and Fe(III)-trivanchrobactin adopts the Λ configuration. Y. ruckeri YRB was also found to produce the antimicrobial agent holomycin (4).
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Affiliation(s)
- Emil Thomsen
- Department of Chemistry & Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - Zachary L Reitz
- Department of Chemistry & Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - Parker R Stow
- Department of Chemistry & Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - Kalana Dulaney
- Department of Chemistry & Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - Alison Butler
- Department of Chemistry & Biochemistry, University of California, Santa Barbara, California 93106, United States
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Ünsaldı E, Kurt-Kızıldoğan A, Özcan S, Becher D, Voigt B, Aktaş C, Özcengiz G. Proteomic analysis of a hom-disrupted, cephamycin C overproducing Streptomyces clavuligerus. Protein Pept Lett 2021; 28:205-220. [PMID: 32707026 DOI: 10.2174/0929866527666200723163655] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 06/18/2020] [Accepted: 06/20/2020] [Indexed: 11/22/2022]
Abstract
BACKGROUND Streptomyces clavuligerus is prolific producer of cephamycin C, a medically important antibiotic. In our former study, cephamycin C titer was 2-fold improved by disrupting homoserine dehydrogenase (hom) gene of aspartate pahway in Streptomyces clavuligerus NRRL 3585. OBJECTIVE In this article, we aimed to provide a comprehensive understanding at the proteome level on potential complex metabolic changes as a consequence of hom disruption in Streptomyces clavuligerus AK39. METHODS A comparative proteomics study was carried out between the wild type and its hom disrupted AK39 strain by 2 Dimensional Electrophoresis-Matrix Assisted Laser Desorption and Ionization Time-Of-Flight Mass Spectrometry (2DE MALDI-TOF/MS) and Nanoscale Liquid Chromatography- Tandem Mass Spectrometry (nanoLC-MS/MS) analyses. Clusters of Orthologous Groups (COG) database was used to determine the functional categories of the proteins. The theoretical pI and Mw values of the proteins were calculated using Expasy pI/Mw tool. RESULTS "Hypothetical/Unknown" and "Secondary Metabolism" were the most prominent categories of the differentially expressed proteins. Upto 8.7-fold increased level of the positive regulator CcaR was a key finding since CcaR was shown to bind to cefF promoter thereby direcly controlling its expression. Consistently, CeaS2, the first enzyme of CA biosynthetic pathway, was 3.3- fold elevated. There were also many underrepresented proteins associated with the biosynthesis of several Non-Ribosomal Peptide Synthases (NRPSs), clavams, hybrid NRPS/Polyketide synthases (PKSs) and tunicamycin. The most conspicuously underrepresented protein of amino acid metabolism was 4-Hydroxyphenylpyruvate dioxygenase (HppD) acting in tyrosine catabolism. The levels of a Two Component System (TCS) response regulator containing a CheY-like receiver domain and an HTH DNA-binding domain as well as DNA-binding protein HU were elevated while a TetR-family transcriptional regulator was underexpressed. CONCLUSION The results obtained herein will aid in finding out new targets for further improvement of cephamycin C production in Streptomyces clavuligerus.
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Affiliation(s)
- Eser Ünsaldı
- Department of Biological Sciences, Middle East Technical University, Ankara 06800, Turkey
| | | | - Servet Özcan
- Department of Biology, Erciyes University, Kayseri 38280, Turkey
| | - Dörte Becher
- Institute of Microbiology, Ernst- Moritz-Arndt-University of Greifswald, Greifswald D-17487, Germany
| | - Birgit Voigt
- Institute of Microbiology, Ernst- Moritz-Arndt-University of Greifswald, Greifswald D-17487, Germany
| | - Caner Aktaş
- Department of Biological Sciences, Middle East Technical University, Ankara 06800, Turkey
| | - Gülay Özcengiz
- Department of Biological Sciences, Middle East Technical University, Ankara 06800, Turkey
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Maglangit F, Yu Y, Deng H. Bacterial pathogens: threat or treat (a review on bioactive natural products from bacterial pathogens). Nat Prod Rep 2021; 38:782-821. [PMID: 33119013 DOI: 10.1039/d0np00061b] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Covering: up to the second quarter of 2020 Threat or treat? While pathogenic bacteria pose significant threats, they also represent a huge reservoir of potential pharmaceuticals to treat various diseases. The alarming antimicrobial resistance crisis and the dwindling clinical pipeline urgently call for the discovery and development of new antibiotics. Pathogenic bacteria have an enormous potential for natural products drug discovery, yet they remained untapped and understudied. Herein, we review the specialised metabolites isolated from entomopathogenic, phytopathogenic, and human pathogenic bacteria with antibacterial and antifungal activities, highlighting those currently in pre-clinical trials or with potential for drug development. Selected unusual biosynthetic pathways, the key roles they play (where known) in various ecological niches are described. We also provide an overview of the mode of action (molecular target), activity, and minimum inhibitory concentration (MIC) towards bacteria and fungi. The exploitation of pathogenic bacteria as a rich source of antimicrobials, combined with the recent advances in genomics and natural products research methodology, could pave the way for a new golden age of antibiotic discovery. This review should serve as a compendium to communities of medicinal chemists, organic chemists, natural product chemists, biochemists, clinical researchers, and many others interested in the subject.
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Affiliation(s)
- Fleurdeliz Maglangit
- Department of Biology and Environmental Science, College of Science, University of the Philippines Cebu, Lahug, Cebu City, 6000, Philippines. and Department of Chemistry, University of Aberdeen, Aberdeen AB24 3UE, UK.
| | - Yi Yu
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (MOE), Hubei Province Engineering and Technology Research Centre for Fluorinated Pharmaceuticals, School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China.
| | - Hai Deng
- Department of Chemistry, University of Aberdeen, Aberdeen AB24 3UE, UK.
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Machado H, Sonnenschein EC, Melchiorsen J, Gram L. Genome mining reveals unlocked bioactive potential of marine Gram-negative bacteria. BMC Genomics 2015; 16:158. [PMID: 25879706 PMCID: PMC4359443 DOI: 10.1186/s12864-015-1365-z] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Accepted: 02/20/2015] [Indexed: 11/10/2022] Open
Abstract
Background Antibiotic resistance in bacteria spreads quickly, overtaking the pace at which new compounds are discovered and this emphasizes the immediate need to discover new compounds for control of infectious diseases. Terrestrial bacteria have for decades been investigated as a source of bioactive compounds leading to successful applications in pharmaceutical and biotech industries. Marine bacteria have so far not been exploited to the same extent; however, they are believed to harbor a multitude of novel bioactive chemistry. To explore this potential, genomes of 21 marine Alpha- and Gammaproteobacteria collected during the Galathea 3 expedition were sequenced and mined for natural product encoding gene clusters. Results Independently of genome size, bacteria of all tested genera carried a large number of clusters encoding different potential bioactivities, especially within the Vibrionaceae and Pseudoalteromonadaceae families. A very high potential was identified in pigmented pseudoalteromonads with up to 20 clusters in a single strain, mostly NRPSs and NRPS-PKS hybrids. Furthermore, regulatory elements in bioactivity-related pathways including chitin metabolism, quorum sensing and iron scavenging systems were investigated both in silico and in vitro. Genes with siderophore function were identified in 50% of the strains, however, all but one harboured the ferric-uptake-regulator gene. Genes encoding the syntethase of acylated homoserine lactones were found in Roseobacter-clade bacteria, but not in the Vibrionaceae strains and only in one Pseudoalteromonas strains. The understanding and manipulation of these elements can help in the discovery and production of new compounds never identified under regular laboratory cultivation conditions. High chitinolytic potential was demonstrated and verified for Vibrio and Pseudoalteromonas species that commonly live in close association with eukaryotic organisms in the environment. Chitin regulation by the ChiS histidine-kinase seems to be a general trait of the Vibrionaceae family, however it is absent in the Pseudomonadaceae. Hence, the degree to which chitin influences secondary metabolism in marine bacteria is not known. Conclusions Utilizing the rapidly developing sequencing technologies and software tools in combination with phenotypic in vitro assays, we demonstrated the high bioactive potential of marine bacteria in an efficient, straightforward manner – an approach that will facilitate natural product discovery in the future.
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Affiliation(s)
- Henrique Machado
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kogle Allè 6, DK-2970, Hørsholm, Denmark. .,Department of Systems Biology, Technical University of Denmark, Matematiktorvet bldg 301, DK-2800, Kgs Lyngby, Denmark.
| | - Eva C Sonnenschein
- Department of Systems Biology, Technical University of Denmark, Matematiktorvet bldg 301, DK-2800, Kgs Lyngby, Denmark.
| | - Jette Melchiorsen
- Department of Systems Biology, Technical University of Denmark, Matematiktorvet bldg 301, DK-2800, Kgs Lyngby, Denmark.
| | - Lone Gram
- Department of Systems Biology, Technical University of Denmark, Matematiktorvet bldg 301, DK-2800, Kgs Lyngby, Denmark.
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Li B, Wever WJ, Walsh CT, Bowers AA. Dithiolopyrrolones: biosynthesis, synthesis, and activity of a unique class of disulfide-containing antibiotics. Nat Prod Rep 2014; 31:905-23. [PMID: 24835149 PMCID: PMC4132845 DOI: 10.1039/c3np70106a] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Covering: up to 2014. Dithiolopyrrolone (DTP) group antibiotics were first isolated in the early half of the 20th century, but only recently has research been reawakened by insights gained from the synthesis and biosynthesis of this structurally intriguing class of molecules. DTPs are characterized by an electronically unique bicyclic structure, which contains a compact disulfide bridge between two ene-thiols. Points of diversity within the compound class occur outside of the bicyclic core, at the two amide nitrogens. Such modifications distinguish three of the most well studied members of the class, holomycin, thiolutin, and aureothricin; the DTP core has also more recently been identified in the marine antibiotic thiomarinol, in which it is linked to a marinolic acid moiety, analog of the FDA-approved topical antibiotic Bactroban® (GlaxoSmithKline). Dithiolopyrrolones exhibit relatively broad-spectrum antibiotic activity against many Gram-positive and Gram-negative bacteria, as well as strains of Mycobacterium tuberculosis. Additionally, they have been shown to exhibit potent and selective anti-cancer activity. Despite this promising profile, there is still much unknown about the mechanisms of action for DTPs. Early reports suggested that they inhibit yeast growth at the level of transcription and that this effect is largely responsible for their distinctive microbial static properties; a similar mechanism is supported in bacteria. Elucidation of biosynthetic pathways for holomycin in Streptomyces clavuligerus and Yersinia ruckeri and thiomarinol in Alteromonas rava sp. nov. SANK 73390, have contributed evidence suggesting that multiple mechanisms may be operative in the activity of these compounds. This review will comprehensively cover the history and development of dithiolopyrrolones with particular emphasis on the biosynthesis, synthesis, biological activity and mechanism of action.
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Affiliation(s)
- Bo Li
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599
| | - Walter J. Wever
- Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Christopher T. Walsh
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 200 Longwood Ave., Boston, MA, 02115
| | - Albert A. Bowers
- Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
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Leite CA, Cavallieri AP, Araujo MLGC. Enhancing effect of lysine combined with other compounds on cephamycin C production in Streptomyces clavuligerus. BMC Microbiol 2013; 13:296. [PMID: 24359569 PMCID: PMC3880171 DOI: 10.1186/1471-2180-13-296] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Accepted: 12/18/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Lysine plays an important role in Streptomyces clavuligerus metabolism; it takes part in its catabolism, via cadaverine, and in its secondary metabolism, in which lysine is converted via 1-piperideine-6-carboxylate to alpha-aminoadipic acid, a beta-lactam antibiotic precursor. The role of lysine as an enhancer of cephamycin C production, when added to production medium at concentrations above 50 mmol l(-1), has already been reported in the literature, with some studies attributing a positive influence to multifunctional diamines, among other compounds. However, there is a lack of research on the combined effect of these compounds on antibiotic production. RESULTS Results from experimental design-based tests were used to conduct response surface-based optimization studies in order to investigate the synergistic effect of combining lysine with cadaverine, putrescine, 1,3-diaminopropane, or alpha-aminoadipic acid on cephamycin C volumetric production. Lysine combined with cadaverine influenced production positively, but only at low lysine concentrations. On the whole, higher putrescine concentrations (0.4 g l(-1)) affected negatively cephamycin C volumetric production. In comparison to culture media containing only lysine as additive, combinations of this amino acid with alpha-aminoadipic acid or 1,3-diaminopropane increased cephamycin C production by more than 100%. CONCLUSION This study demonstrated that different combinations of lysine with diamines or lysine with alpha-aminoadipic acid engender significant differences with respect to antibiotic volumetric production, with emphasis on the benefits observed for lysine combined with alpha-aminoadipic acid or 1,3-diaminopropane. This increase is explained by mathematical models and demonstrated by means of bioreactor cultivations. Moreover, it is consistent with the positive influence of these compounds on lysine conversion to alpha-aminoadipic acid, a limiting step in cephamycin C production.
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Affiliation(s)
- Carla A Leite
- Department of Biochemistry and Technological Chemistry, UNESP - São Paulo State University, Institute of Chemistry, 14800-900 Araraquara, SP, Brazil
| | - André P Cavallieri
- Department of Biochemistry and Technological Chemistry, UNESP - São Paulo State University, Institute of Chemistry, 14800-900 Araraquara, SP, Brazil
| | - Maria L G C Araujo
- Department of Biochemistry and Technological Chemistry, UNESP - São Paulo State University, Institute of Chemistry, 14800-900 Araraquara, SP, Brazil
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Holomycin, a dithiolopyrrolone compound produced by Streptomyces clavuligerus. Appl Microbiol Biotechnol 2013; 98:1023-30. [DOI: 10.1007/s00253-013-5410-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Revised: 11/13/2013] [Accepted: 11/13/2013] [Indexed: 01/19/2023]
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Qin Z, Huang S, Yu Y, Deng H. Dithiolopyrrolone natural products: isolation, synthesis and biosynthesis. Mar Drugs 2013; 11:3970-97. [PMID: 24141227 PMCID: PMC3826145 DOI: 10.3390/md11103970] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Revised: 09/25/2013] [Accepted: 09/26/2013] [Indexed: 12/24/2022] Open
Abstract
Dithiolopyrrolones are a class of antibiotics that possess the unique pyrrolinonodithiole (4H-[1,2] dithiolo [4,3-b] pyrrol-5-one) skeleton linked to two variable acyl groups. To date, there are approximately 30 naturally occurring dithiolopyrrolone compounds, including holomycin, thiolutin, and aureothricin, and more recently thiomarinols, a unique class of hybrid marine bacterial natural products containing a dithiolopyrrolone framework linked by an amide bridge with an 8-hydroxyoctanoyl chain linked to a monic acid. Generally, dithiolopyrrolone antibiotics have broad-spectrum antibacterial activity against various microorganisms, including Gram-positive and Gram-negative bacteria, and even parasites. Holomycin appeared to be active against rifamycin-resistant bacteria and also inhibit the growth of the clinical pathogen methicillin-resistant Staphylococcus aureus N315. Its mode of action is believed to inhibit RNA synthesis although the exact mechanism has yet to be established in vitro. A recent work demonstrated that the fish pathogen Yersinia ruckeri employs an RNA methyltransferase for self-resistance during the holomycin production. Moreover, some dithiolopyrrolone derivatives have demonstrated promising antitumor activities. The biosynthetic gene clusters of holomycin have recently been identified in S. clavuligerus and characterized biochemically and genetically. The biosynthetic gene cluster of thiomarinol was also identified from the marine bacterium Pseudoalteromonas sp. SANK 73390, which was uniquely encoded by two independent pathways for pseudomonic acid and pyrrothine in a novel plasmid. The aim of this review is to give an overview about the isolations, characterizations, synthesis, biosynthesis, bioactivities and mode of action of this unique family of dithiolopyrrolone natural products, focusing on the period from 1940s until now.
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Affiliation(s)
- Zhiwei Qin
- Key Laboratory of Combinatory Biosynthesis and Drug Discovery (Ministry of Education), School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China; E-Mails: (Z.Q.); (S.H.)
- Marine Biodiscovery Centre, Department of Chemistry, University of Aberdeen, Aberdeen AB24 3UE, Scotland, UK
| | - Sheng Huang
- Key Laboratory of Combinatory Biosynthesis and Drug Discovery (Ministry of Education), School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China; E-Mails: (Z.Q.); (S.H.)
| | - Yi Yu
- Key Laboratory of Combinatory Biosynthesis and Drug Discovery (Ministry of Education), School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China; E-Mails: (Z.Q.); (S.H.)
| | - Hai Deng
- Marine Biodiscovery Centre, Department of Chemistry, University of Aberdeen, Aberdeen AB24 3UE, Scotland, UK
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Guo D, Zhao Y, Yang K. Coordination of glycerol utilization and clavulanic acid biosynthesis to improve clavulanic acid production in Streptomyces clavuligerus. SCIENCE CHINA-LIFE SCIENCES 2013; 56:591-600. [PMID: 23832248 DOI: 10.1007/s11427-013-4507-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2013] [Accepted: 05/28/2013] [Indexed: 11/26/2022]
Abstract
The glycerol utilization (gyl) operon is involved in clavulanic acid (CA) production by Streptomyces clavuligerus, and possibly supplies the glyceraldehyde-3-phosphate (G3P) precursor for CA biosynthesis. The gyl operon is regulated by GylR and is induced by glycerol. To enhance CA production in S. clavuligerus, an extra copy of ccaR expressed from Pgyl (the gyl promoter) was integrated into the chromosome of S. clavuligerus NRRL 3585. This construct coordinated the transcription of CA biosynthetic pathway genes with expression of the gyl operon. In the transformants carrying the Pgyl-controlled regulatory gene ccaR, CA production was enhanced 3.19-fold in glycerol-enriched batch cultures, relative to the control strain carrying an extra copy of ccaR controlled by its own promoter (PccaR). Consistent with enhanced CA production, the transcription levels of ccaR, ceas2 and claR were significantly up-regulated in the transformants containing Pgyl-controlled ccaR.
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Affiliation(s)
- Dekun Guo
- School of Life Sciences, University of Science and Technology of China, Hefei 230027, China
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Enhancement of FK506 production by engineering secondary pathways of Streptomyces tsukubaensis and exogenous feeding strategies. J Ind Microbiol Biotechnol 2013; 40:1023-37. [PMID: 23779221 DOI: 10.1007/s10295-013-1301-7] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Accepted: 05/29/2013] [Indexed: 01/13/2023]
Abstract
FK506 is a clinically important macrocyclic polyketide with immunosuppressive activity produced by Streptomyces tsukubaensis. However, the low titer at which it is produced is a bottleneck to its application and use in industrial processes. We have overexpressed five potential targets associated with FK506 production (fkbO, fkbL, fkbP, fkbM, fkbD) which were identified in our previous study, with the aim to improve FK506 production. The results of the analysis showed that the constructed strains with an additional copy of each gene increased FK506 production by approximately 10-40 % compared with the wild-type strain D852. The results of the gene expression analysis indicated that each gene was upregulated. Combinatorial overexpression of the five genes resulted in a 146 % increase in the FK506 titer to 353.2 mg/L, in comparison with the titer produced by D852. To further improve the production of FK506 by the engineered strain HT-FKBOPLMD, we supplemented the medium with various nutrients, including soybean oil, lactate, succinate, shikimate, chorismate, lysine, pipecolate, isoleucine and valine. Optimization of feeding concentrations and times resulted in HT-FKBOPLMD being able to produce approximately 70 % more FK506, thereby reaching the maximal titer of 457.5 mg/L, with lower amounts of by-products (FK520 and 37,38-dihydro-FK506). These results demonstrate that the combination of the metabolically engineered secondary pathways and the exogenous feeding strategies developed here was able to be successfully applied to improve the production of industrially and clinically important compounds.
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