Chemical structure metagenomics of microbial natural products: surveying nonribosomal peptides and beyond

• Thomas Ma and
• John Chu

Beilstein J. Org. Chem. 2024, 20, 3050–3060, doi:10.3762/bjoc.20.253

• may also benefit from bioinformatic studies of adenylating enzymes in general; the discovery of a novel β-lactone biosynthesis pathway in Nocardia species is a good case in point [78]. Future directions 2: Understanding thioesterase function No algorithm is currently capable of predicting the topology

Methodology for awakening the potential secondary metabolic capacity in actinomycetes

• Shun Saito and
• Midori A. Arai

Beilstein J. Org. Chem. 2024, 20, 753–766, doi:10.3762/bjoc.20.69

• defensive compounds as a countermeasure. Therefore, the pathogenic actinomycetes were co-cultured with J774.1 mouse macrophage-like cells (Figure 5b). The first compound isolated was nocarjamide (52), a cyclic nonapeptide, discovered by co-culturing Nocardia tenerifensis IFM 10554T with J774.1 cells [121

• A and B (54, 55), which were discovered by co-culturing Nocardia uniformis IFM0856T and J774.1 cells [124][125]. Uniformides were shown to suppress the production of nitric oxide, IL-6, and IL-1β by inhibiting the NF-κB pathway. Because NF-κB signaling plays a central role in the immune response

Functions of enzyme domains in 2-methylisoborneol biosynthesis and enzymatic synthesis of non-natural analogs

• Binbin Gu,
• Lin-Fu Liang and
• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2023, 19, 1452–1459, doi:10.3762/bjoc.19.104

• different organisms can have a variable lengths ranging from ca. 330 amino acids (e.g., in Longispora albida DSM 44784, accession number WP_018349754, 329 amino acids) to more than 550 amino acids (e.g., in Nocardia amikacinitolerans DSM 45535, accession number WP_253814817, 580 amino acids). The long

Functional characterisation of twelve terpene synthases from actinobacteria

• Anuj K. Chhalodia,
• Houchao Xu,
• Georges B. Tabekoueng,
• Binbin Gu,
• Kizerbo A. Taizoumbe,
• Lukas Lauterbach and
• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2023, 19, 1386–1398, doi:10.3762/bjoc.19.100

• identifying the investigated enzyme as Nocardia brevicatena epi-isozizaene synthase (NbEIZS). GGPP was not converted, but the incubation with GPP resulted in the production of a complex mixture of monoterpenes including myrcene (14), sylvestrene (15), γ-terpinene (16), cis-sabinene hydrate (17), terpinolene

• sufficiently distant to expect novel functions, were shown to still form the same products as the previously characterised enzymes. However, the epi-isozizaene synthase from Nocardia brevifolia exhibited in contrast to the known enzyme from Streptomyces bungoensis [45] a substantial monoterpene synthase

Amamistatins isolated from Nocardia altamirensis

• Till Steinmetz,
• Wolf Hiller and
• Markus Nett

Beilstein J. Org. Chem. 2022, 18, 360–367, doi:10.3762/bjoc.18.40

• Abstract Four new phenolic siderophores were isolated from the actinomycete Nocardia altamirensis along with the known natural product amamistatin B and a putative biosynthetic shunt product. The structures of all compounds were elucidated through 1D and 2D NMR analyses as well as mass spectrometry. The

• iron-chelating properties of the retrieved metabolites were evaluated in a chrome azurol S assay. Keywords: actinomycete; amamistatin; Nocardia; siderophore; structure elucidation; Introduction Iron is known to easily interconvert between a reduced ferrous (Fe2+) and an oxidized ferric state (Fe3

• featuring ligand groups with nitrogen or sulfur as donor atoms [4]. The siderophore–iron complexes are recognized by highly selective microbial transporters. Following their translocation into the cell, the bound iron is released via a reductive or hydrolytic mechanism [2] Members of the genus Nocardia are

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

• 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

Strategies in megasynthase engineering – fatty acid synthases (FAS) as model proteins

• Manuel Fischer and
• Martin Grininger

Beilstein J. Org. Chem. 2017, 13, 1204–1211, doi:10.3762/bjoc.13.119

• both in FAS as well as PKS systems, but it is differing in its specific structural manifestation. In fungal FAS (and bacterial type I FAS occurring in Corynebacterium, Mycobacterium and Nocardia of the genus Actinomycetales), nature evolved a D3-symmetric barrel-shaped structure of 2.6 MDa, which

Enantioconvergent catalysis

• Justin T. Mohr,
• Jared T. Moore and
• Brian M. Stoltz

Beilstein J. Org. Chem. 2016, 12, 2038–2045, doi:10.3762/bjoc.12.192

• % ee [36]. An especially remarkable example of type III enantioconvergent catalysis utilizes a single enzymatic catalyst. Faber observed that Nocardia EH1 is capable of catalyzing the hydrolysis of racemic epoxide 33 to the corresponding diol (2R,3R)-34 in 79% chemical yield with 91% ee (Scheme 8) [37

• protonation (dba = dibenzylideneacetone). Enantioconvergent allylic alkylation with two racemic starting materials. Enantioconvergent parallel kinetic resolution by two complementary biocatalysts. Enantioconvergent PKR by Nocardia EH1. Acknowledgements This publication is supported in part by the NIH-NIGMS

Biosynthesis of α-pyrones

• Till F. Schäberle

Beilstein J. Org. Chem. 2016, 12, 571–588, doi:10.3762/bjoc.12.56

• residue – indicating a mechanism distinct from the ketoacyl–ketoacyl-connecting KSs – and were identified in different bacterial genera, i.e., Burkholderia, Legionella, Nocardia, Microcystis and Streptomyces, therewith also in clinically relevant pathogens [63]. Future work will reveal which natural

Synthesis of α,β-unsaturated esters via a chemo-enzymatic chain elongation approach by combining carboxylic acid reduction and Wittig reaction

• Yitao Duan,
• Peiyuan Yao,
• Yuncheng Du,
• Jinhui Feng,
• Qiaqing Wu and
• Dunming Zhu

Beilstein J. Org. Chem. 2015, 11, 2245–2251, doi:10.3762/bjoc.11.243

• high identity with the carboxylic acid reductase (CAR) gene from Nocardia iowensis. These two putative CAR genes were cloned, overexpressed in E. coli and one of two proteins could reduce 1a. The recombinant CAR was purified and characterized. The enzyme exhibited high activity toward a variety of

• been identified, a known Nocardia PPTase (accession number ABI83656.1) was selected for the post-translational phosphopantetheinylation in the current study [27][28]. The gene (Gene ID 17912504) was cloned into pET30b(+) and expressed in E. coli. The recombinant enzyme (Mycobacterium CAR) showed

• observations for the reaction with the carboxylic acid reductases from Nocardia [29][35] and Segniliparus [28]. The optimal pH and temperature for the enzymatic reduction of 1a with Mycobacterium CAR were pH 9 and 25 °C, respectively. The apparent Km and catalytic efficiencies (kcat/Km) of Mycobacterium CAR

A novel and widespread class of ketosynthase is responsible for the head-to-head condensation of two acyl moieties in bacterial pyrone biosynthesis

• Darko Kresovic,
• Florence Schempp,
• Zakaria Cheikh-Ali and
• Helge B. Bode

Beilstein J. Org. Chem. 2015, 11, 1412–1417, doi:10.3762/bjoc.11.152

• . The biosynthetic importance of the second group including PpyS homologues from Burkholderia, Legionella, Nocardia, Microcystis and Streptomyces needs to be determined in future work. In contrary, MxnB and CorB are located within the FabH clade, showing that not only the reaction mechanism of these two

The volatiles of pathogenic and nonpathogenic mycobacteria and related bacteria

• Thorben Nawrath,
• Georgies F. Mgode,
• Bart Weetjens,
• Stefan H. E. Kaufmann and
• Stefan Schulz

Beilstein J. Org. Chem. 2012, 8, 290–299, doi:10.3762/bjoc.8.31

• mycobacteria, as well as by mycobacteria-related Nocardia spp., were analyzed. Bacteria were cultivated on solid and in liquid media, and headspace samples were collected at various times during the bacterial lifecycle to elucidate the conditions giving optimal volatile emission. Emitted volatiles were

• fatty-acid derivatives were released by pathogenic/nonpathogenic mycobacteria, while the two Nocardia spp. (N. asteroides and N. africana) emitted the sesquiterpene aciphyllene. Pathogenic Mycobacterium tuberculosis strains grown on agar plates produced a distinct bouquet with different volatiles, while

• -recognition methods, such as electronic noses and trained Cricetomys rats. We report here on the identification of volatiles produced by different strains of M. tuberculosis, as well as of M. smegmatis, M. aurum, M. neoaurum, M. aichiense, M. scrofulaceum, M. avium spp. avium, M. vaccae, Nocardia africana