Recent synthesis of thietanes

• Jiaxi Xu

Beilstein J. Org. Chem. 2020, 16, 1357–1410, doi:10.3762/bjoc.16.116

A cyclopeptide and three oligomycin-class polyketides produced by an underexplored actinomycete of the genus Pseudosporangium

• Shun Saito,
• Kota Atsumi,
• Tao Zhou,
• Keisuke Fukaya,
• Daisuke Urabe,
• Naoya Oku,
• Md. Rokon Ul Karim,
• Hisayuki Komaki and
• Yasuhiro Igarashi

Beilstein J. Org. Chem. 2020, 16, 1100–1110, doi:10.3762/bjoc.16.97

• , National Institute of Technology and Evaluation (NBRC), Kisarazu, Chiba 292-0818, Japan 10.3762/bjoc.16.97 Abstract Aside from the well-studied conventional actinomycetes such as Streptomyces, the less investigated genera of actinomycetes also represent a promising source of natural products. Genome

• widely used as an indicator of the taxonomic position of prokaryotes. It was believed that a high similarity of the 16S rRNA gene sequence implied the closeness or even the identity in other sets of genes including secondary metabolite biosynthetic genes. However, our recent analysis of Streptomyces

• actinomycetes” refers to non-Streptomyces actinomycetes [12] and the representative genera, such as Micromonospora, Actinomadura, Nocardia, Actinoplanes, and Saccharothrix, which are no longer rare in terms of difficulties in isolation, already provided thousands of new metabolites [13][14]. Meanwhile, the

Understanding the role of active site residues in CotB2 catalysis using a cluster model

• Keren Raz,
• Ronja Driller,
• Thomas Brück,
• Bernhard Loll and
• Dan T. Major

Beilstein J. Org. Chem. 2020, 16, 50–59, doi:10.3762/bjoc.16.7

• , Dept. of Chemistry, Technical University of Munich (TUM), Lichtenbergstr. 4, 85748 Garching, Germany 10.3762/bjoc.16.7 Abstract Terpene cyclases are responsible for the initial cyclization cascade in the multistep synthesis of a large number of terpenes. CotB2 is a diterpene cyclase from Streptomyces

Bacterial terpene biosynthesis: challenges and opportunities for pathway engineering

• Eric J. N. Helfrich,
• Geng-Min Lin,
• Christopher A. Voigt and
• Jon Clardy

Beilstein J. Org. Chem. 2019, 15, 2889–2906, doi:10.3762/bjoc.15.283

• expression is the most widely used method to study complex terpenoid biosyntheses. Since many bacterial terpenoid BGCs are actinomycete-derived, terpene BGCs are often expressed in model Streptomyces hosts, such as Streptomyces albus, Streptomyces avermitilis, Streptomyces coelicolor, and Streptomyces

• lividans, under the control of exogenous promoters [92][93][94]. To minimize the cellular resource competition and facilitate cleaner analysis, many of these hosts have been engineered to remove native secondary-metabolite BGCs and for optimized terpene precursor supply [1][95][96][97]. Like Streptomyces

Current understanding and biotechnological application of the bacterial diterpene synthase CotB2

• Ronja Driller,
• Daniel Garbe,
• Norbert Mehlmer,
• Monika Fuchs,
• Keren Raz,
• Dan Thomas Major,
• Thomas Brück and
• Bernhard Loll

Beilstein J. Org. Chem. 2019, 15, 2355–2368, doi:10.3762/bjoc.15.228

• , Technical University of Munich (TUM), Lichtenbergstr. 4, 85748 Garching, Germany Department of Chemistry, Bar-Ilan University, Ramat-Gan 52900, Israel 10.3762/bjoc.15.228 Abstract CotB2 catalyzes the first committed step in cyclooctatin biosynthesis of the soil bacterium Streptomyces melanosporofaciens. To

• exclusively belong to class I TPSs. A few exceptions exist, for example the terpentedienyl-diphosphate synthase from Kitasatospora griseola [19], which belongs to class II, and PtmT1 from Streptomyces platensis in the platensimycin gene cluster [20], which is neither characteristic for class I nor class II

• cyclooctatin biosynthetic gene cluster in particular the TPS CotB2 from the soil bacterium Streptomyces melanosporofaciens MI614-43F2 (Figure 1) [31]. Cyclooctatin 5, with its distinct 5–8–5 ring motif, belongs to the fusicoccane diterpenoids that encompass a wide range of bioactivities, such as bacteriostatic

Phylogenomic analyses and distribution of terpene synthases among Streptomyces

• Lara Martín-Sánchez,
• Kumar Saurabh Singh,
• Mariana Avalos,
• Gilles P. van Wezel,
• Jeroen S. Dickschat and
• Paolina Garbeva

Beilstein J. Org. Chem. 2019, 15, 1181–1193, doi:10.3762/bjoc.15.115

• /bjoc.15.115 Abstract Terpene synthases are widely distributed among microorganisms and have been mainly studied in members of the genus Streptomyces. However, little is known about the distribution and evolution of the genes for terpene synthases. Here, we performed whole-genome based phylogenetic

• analysis of Streptomyces species, and compared the distribution of terpene synthase genes among them. Overall, our study revealed that ten major types of terpene synthases are present within the genus Streptomyces, namely those for geosmin, 2-methylisoborneol, epi-isozizaene, 7-epi-α-eudesmol, epi-cubenol

• , caryolan-1-ol, cyclooctat-9-en-7-ol, isoafricanol, pentalenene and α-amorphene. The Streptomyces species divide in three phylogenetic groups based on their whole genomes for which the distribution of the ten terpene synthases was analysed. Geosmin synthases were the most widely distributed and were found

Multicomponent reactions (MCRs): a useful access to the synthesis of benzo-fused γ-lactams

• Edorta Martínez de Marigorta,
• Jesús M. de Los Santos,
• Ana M. Ochoa de Retana,
• Javier Vicario and
• Francisco Palacios

Beilstein J. Org. Chem. 2019, 15, 1065–1085, doi:10.3762/bjoc.15.104

• from Phalaris coerulescens (Figure 3). Likewise, maremycins [13] and spirotryprostatin B [14] have been isolated from marine Streptomyces and from the fermentation broth of Aspergillus fumigatus. Among benzo-fused γ-lactam chemical entities, natural and synthetic isoindolinones are a prominent class of

Mechanistic investigations on multiproduct β-himachalene synthase from Cryptosporangium arvum

• Jan Rinkel and
• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2019, 15, 1008–1019, doi:10.3762/bjoc.15.99

• configuration of 1. For 1, C-5 was targeted by (1R)- and (1S)-(1-13C,1-2H)GPP [28], which were enzymatically elongated with isopentenyl diphosphate (IPP) by farnesyl diphosphate synthase (FPPS) from Streptomyces coelicolor [29] with a known stereochemical course [30] (Figure S4, Supporting Information File 1

Stereochemical investigations on the biosynthesis of achiral (Z)-γ-bisabolene in Cryptosporangium arvum

• Jan Rinkel and
• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2019, 15, 789–794, doi:10.3762/bjoc.15.75

• terpinyl cation has been investigated using deuterium labelling, demonstrating different stereochemical courses in the plant Salvia officinalis [8][9] and in the bacterium Streptomyces clavuligerus [10]. Also the highly unusual methylated sesquiterpene sodorifen (4) possesses a mirror plane [11] making any

Lectins of Mycobacterium tuberculosis – rarely studied proteins

• Katharina Kolbe,
• Sri Kumar Veleti,
• Norbert Reiling and
• Thisbe K. Lindhorst

Beilstein J. Org. Chem. 2019, 15, 1–15, doi:10.3762/bjoc.15.1

• Streptomyces olivaceoviridis) [77][78]. This secreted protein was crystallized in 2010 by Patra et al., however, a three-dimensional structure has yet to be resolved [79]. Recently Nogueira et al. detected high titers of IgG antibodies against sMTL-13 in sera from TB patients, a response found to be diminished

• shown as blue arrows. B) sMTL-13 (aa28-155), encoded by Rv1419, showed with 100% confidence sequence similarity to a ricin B-like lectin of Streptomyces olivaceoviridis, the sequence identity was 22%. C) Known domain structure of HBHA (Rv0475): Transmembrane domain (TM), coiled coil domain, and heparin

Protein–protein interactions in bacteria: a promising and challenging avenue towards the discovery of new antibiotics

• Laura Carro

Beilstein J. Org. Chem. 2018, 14, 2881–2896, doi:10.3762/bjoc.14.267

• of rapamycin) [34]. This natural product, isolated from Streptomyces hygroscopicus, was one of the first protein–protein interaction stabilizers reported: it first binds to its receptor (i.e., FKBP12) with high affinity, after which the FKBP12-rapamycin complex will associate with TOR resulting in

• displayed no activity [67]. Historically, natural products have been one of the most fruitful sources to obtain antibacterial lead compounds [5][68][69]. Griselimycin, a cyclic depsidecapeptide isolated from Streptomyces sp., was discovered fifty years ago, nonetheless, due to its poor pharmacokinetic

Synthesis of a leopolic acid-inspired tetramic acid with antimicrobial activity against multidrug-resistant bacteria

• Luce Mattio,
• Loana Musso,
• Leonardo Scaglioni,
• Andrea Pinto,
• Piera Anna Martino and
• Sabrina Dallavalle

Beilstein J. Org. Chem. 2018, 14, 2482–2487, doi:10.3762/bjoc.14.224

• , as they possess biologically validated structures, which could become suitable leads in drug discovery [2]. Recently, our research group reported the first total synthesis of leopolic acid A (Figure 1), a fungal metabolite from a terrestrial-derived Streptomyces sp. isolated from the rhizosphere of

Synthesis of eunicellane-type bicycles embedding a 1,3-cyclohexadiene moiety

• Alex Frichert,
• Peter G. Jones and
• Thomas Lindel

Beilstein J. Org. Chem. 2018, 14, 2461–2467, doi:10.3762/bjoc.14.222

• the plant Vellozia magdalenae [6]. Recently, prehydropyrene (6) was discovered as biosynthetic intermediate towards the diterpene hydropyrene from the Gram-positive bacterium Streptomyces clavuligerus [7]. The six- and ten-membered rings of eunicellane diterpenoids can be either cis or trans fused

Synthesis of spirocyclic scaffolds using hypervalent iodine reagents

• Fateh V. Singh,
• Priyanka B. Kole,
• Saeesh R. Mangaonkar and
• Samata E. Shetgaonkar

Beilstein J. Org. Chem. 2018, 14, 1778–1805, doi:10.3762/bjoc.14.152

• pathway for the synthesis of the naturally occurring antibiotic platensimycin (154) which is isolated from Streptomyces platensis. In this report, 6-methoxy-1,4-naphthoquinone-4-ethylene ketal (153) was synthesized by intermolecular oxidative cyclization of 7-methoxy-α-naphthol (152) with ethylene glycol

β-Hydroxy sulfides and their syntheses

• Mokgethwa B. Marakalala,
• Edwin M. Mmutlane and
• Henok H. Kinfe

Beilstein J. Org. Chem. 2018, 14, 1668–1692, doi:10.3762/bjoc.14.143

• exemplified by leukotriene E4 (8) isolated from the mast cells and extensively studied for allergy and asthma [11]. Another example is grisemycin (9) from Streptomyces griseus M268, which contains an unusual ether-bridged system and a methylsulfinyl substituent [12]. Cyclothiocurvularin (10), isolated from

Lanyamycin, a macrolide antibiotic from Sorangium cellulosum, strain Soce 481 (Myxobacteria)

• Lucky S. Mulwa,
• Rolf Jansen,
• Dimas F. Praditya,
• Kathrin I. Mohr,
• Patrick W. Okanya,
• Joachim Wink,
• Eike Steinmann and
• Marc Stadler

Beilstein J. Org. Chem. 2018, 14, 1554–1562, doi:10.3762/bjoc.14.132

• masked as a hemiketal in bafilomycins, e.g., in bafilomycin A1 [11][12][13][14]. Bafilomycins are a family of macrolide antibiotics isolated from actinobacteria such as Micromonospora and Streptomyces species [11]. They are specific inhibitors of vacuolar ATPase (V-ATPase) [15]. The most studied compound

Two new 2-alkylquinolones, inhibitory to the fish skin ulcer pathogen Tenacibaculum maritimum, produced by a rhizobacterium of the genus Burkholderia sp.

• Dandan Li,
• Naoya Oku,
• Atsumi Hasada,
• Masafumi Shimizu and
• Yasuhiro Igarashi

Beilstein J. Org. Chem. 2018, 14, 1446–1451, doi:10.3762/bjoc.14.122

• sizes of B. cepacia ATCC25416, Paraburkholderia terrae DSM 17804, and Caballeronia glathei DSM50014 are 8.61, 10.1, and 8.64 Mbp, respectively, which are comparable to 9.05 Mbp for Streptomyces coelicolor A3(2) and 9.14 Mbp for Myxococcus xanthus DK 1622, both known as representatives of prolific

An overview of recent advances in duplex DNA recognition by small molecules

• Sayantan Bhaduri,
• Nihar Ranjan and
• Dev P. Arya

Beilstein J. Org. Chem. 2018, 14, 1051–1086, doi:10.3762/bjoc.14.93

On the design principles of peptide–drug conjugates for targeted drug delivery to the malignant tumor site

• Eirinaios I. Vrettos,
• Gábor Mező and
• Andreas G. Tzakos

Beilstein J. Org. Chem. 2018, 14, 930–954, doi:10.3762/bjoc.14.80

• anthracycline discovered that was extracted from Streptomyces peucetius, a species of actinobacteria, at the beginning of the 1960s. Shortly after, the isolation of doxorubicin (Dox) from a mutated Streptomyces strain was accomplished. Anthracyclines are consisted of a tetracyclin aglycon part and a daunosamine

A Brønsted base-promoted diastereoselective dimerization of azlactones

• Danielle L. J. Pinheiro,
• Gabriel M. F. Batista,
• Pedro P. de Castro,
• Leonã S. Flores,
• Gustavo F. S. Andrade and
• Giovanni W. Amarante

Beilstein J. Org. Chem. 2017, 13, 2663–2670, doi:10.3762/bjoc.13.264

• diastereomer was assigned by X-ray analysis. Finally, one of the products was selectively reduced to provide a functionalized analogue of streptopyrrolidine, a marine natural product isolated from Streptomyces sp. As shown in Table 1, our studies started with the synthesis of dimer 2a using azlactone 1a in the

• (Scheme 3). Compound 2c was dissolved in a mixture of acetic acid and NaBH4, cooled to 0 °C to afford the highly functionalized (+/−)-streptopyrrolidine analogue 6 in 70% yield as a unique diastereomer. Streptopyrrolidine was isolated from the marine bacterium Streptomyces sp. and has exhibited a

Sulfation and amidinohydrolysis in the biosynthesis of giant linear polyenes

• Hui Hong,
• Markiyan Samborskyy,
• Katsiaryna Usachova,
• Katharina Schnatz and
• Peter F. Leadlay

Beilstein J. Org. Chem. 2017, 13, 2408–2415, doi:10.3762/bjoc.13.238

• Hui Hong Markiyan Samborskyy Katsiaryna Usachova Katharina Schnatz Peter F. Leadlay Department of Biochemistry, University of Cambridge, Cambridge CB2 1GA, UK 10.3762/bjoc.13.238 Abstract Clethramycin from Streptomyces malaysiensis DSM4137, and mediomycins (produced together with clethramycin

• from Streptomyces mediocidicus), are near-identical giant linear polyenes apparently constructed from, respectively, a 4-guanidinobutanoate or 4-aminobutanoate starter unit and 27 polyketide extender units, and bearing a specific O-sulfonate modification at the C-29 hydroxy group. We show here that

• polyene clethramycin (1a, Scheme 1), originally isolated as an antifungal and as an inhibitor of pollen tube outgrowth from a plant-associated Streptomyces hygroscopicus strain [5]. Clethramycin (together with desulfoclethramycin (1b)) is also a product of the prolific strain Streptomyces malaysiensis

Enzymatic synthesis of glycosides: from natural O- and N-glycosides to rare C- and S-glycosides

• Jihen Ati,
• Pierre Lafite and
• Richard Daniellou

Beilstein J. Org. Chem. 2017, 13, 1857–1865, doi:10.3762/bjoc.13.180

• acceptor. UGT74B1, involved in glucosinolate biosynthesis (see supra), was one of these 17 enzymes. Other studies have identified S-GT activities when assaying the catalytic promiscuity of O-GT with a wide range of aglycone acceptors (Figure 3). OleD from Streptomyces antibioticus has been the first

• [39] or Mangifera indica [40] (Figure 4). Fungi C-glycosyltransferases were also identified in Streptomyces, including UrdGT [41][42] and SsfS6 [43] that catalyse the transfer of the unusual D-olivosyl carbohydrate moiety on the aglycon acceptor. Bacterial C-GTs are the last group identified in

18-Hydroxydolabella-3,7-diene synthase – a diterpene synthase from Chitinophaga pinensis

• Jeroen S. Dickschat,
• Jan Rinkel,
• Patrick Rabe,
• Arman Beyraghdar Kashkooli and
• Harro J. Bouwmeester

Beilstein J. Org. Chem. 2017, 13, 1770–1780, doi:10.3762/bjoc.13.171

• (−)-bornyl diphosphate synthases from the plants Salvia officinalis and Tanacetum vulgare forming a more polar product by the unusual termination via reattack of diphosphate [1], the trichodiene synthase from the fungus Trichothecium roseum [2], and pentalenene synthase from Streptomyces exfoliatus [3

• reports: [7][8][9][10][11][12][13][14]). One possible method to investigate the products of terpene synthases is the expression of terpene synthase genes in a heterologous host, as was recently performed for a large number of bacterial enzymes in an engineered Streptomyces avermitilis strain from which

Cycloheximide congeners produced by Streptomyces sp. SC0581 and photoinduced interconversion between (E)- and (Z)-2,3-dehydroanhydrocycloheximides

• Li Yang,
• Ping Wu,
• Jinghua Xue,
• Huitong Tan,
• Zheng Zhang and
• Xiaoyi Wei

Beilstein J. Org. Chem. 2017, 13, 1039–1049, doi:10.3762/bjoc.13.103

• , anhydroisoheximide (4), cycloheximide (5), and isocycloheximide (6), were obtained from the cultures of Streptomyces sp. SC0581. Their structures were elucidated by extensive spectroscopic analysis in combination with theoretical conformational analysis and ECD computations. The photoinduced interconversion between

• important to the activities of cycloheximide congeners. Keywords: antifungal activity; cycloheximide derivatives; E/Z photoisomerization; Streptomyces sp; theoretical conformational analysis; Introduction The glutarimide-containing antibiotics represent a fascinating class of natural products that exhibit

• without the toxic side-effects could provide a viable lead of therapeutic drugs or agricultural pesticides. During the course of our searching for bioactive microbial metabolites [8][9], a culture extract of Streptomyces sp. SC0581 was found to show antifungal activity against the phytopathogen

Total synthesis of TMG-chitotriomycin based on an automated electrochemical assembly of a disaccharide building block

• Yuta Isoda,
• Norihiko Sasaki,
• Kei Kitamura,
• Shuji Takahashi,
• Sujit Manmode,
• Naoko Takeda-Okuda,
• Jun-ichi Tamura,
• Toshiki Nokami and
• Toshiyuki Itoh

Beilstein J. Org. Chem. 2017, 13, 919–924, doi:10.3762/bjoc.13.93

• developed. These compounds have exhibited strong inhibition activity; however, they have a broad spectrum toward enzymes of various species including animals (Figure 1). N,N,N-Trimethyl-D-glucosaminyl (TMG)-chitotriomycin (1) was isolated from Streptomyces anulatus by Kanzaki [5][6][7] and the first total