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

• “rare actinomycetes”, and the secondary metabolites produced by these species have thus attracted increasing attention. Indeed, an increasing proportion of newly identified antibiotics are reportedly produced by rare actinomycetes [20]. Igarashi and colleagues have also focused on various rare

• actinomycetes, analyzing their secondary metabolic activity and demonstrating the importance of studying new genera and species [21][22][23][24][25]. On the other hand, it is now thought that secondary metabolic activities remain to be analyzed in actinomycetes, including Streptomyces strains, which were

A new analog of dihydroxybenzoic acid from Saccharopolyspora sp. KR21-0001

• Rattiya Janthanom,
• Yuta Kikuchi,
• Hiroki Kanto,
• Tomoyasu Hirose,
• Arisu Tahara,
• Takahiro Ishii,
• Arinthip Thamchaipenet and
• Yuki Inahashi

Beilstein J. Org. Chem. 2024, 20, 497–503, doi:10.3762/bjoc.20.44

• important because of their beneficial health effects. Recently, the discovery of new compounds has diverted attention to rare actinomycetes, since they are rich sources of natural products. In this study, a collection of rare actinomycetes at Kitasato University has been screened for potential novel

• compound producers. Among the rare actinomycetes, Saccharopolyspora sp. KR21-0001 isolated from soil on Ōha Island, Okinawa, Japan was selected as a potential producer. The strain was cultured in 20 L of production medium in a jar fermenter and the culture broth was extracted. Further purification revealed

• but showed potent antioxidant activity. Keywords: antioxidant activity; dihydroxybenzoic acid analog; rare actinomycetes; Introduction Actinomycetes are Gram-positive bacteria with high GC content in their genome. They are well-known as the main producers of bioactive compounds such as antibiotic

Identification of the p-coumaric acid biosynthetic gene cluster in Kutzneria albida: insights into the diazotization-dependent deamination pathway

• Seiji Kawai,
• Akito Yamada,
• Yohei Katsuyama and
• Yasuo Ohnishi

Beilstein J. Org. Chem. 2024, 20, 1–11, doi:10.3762/bjoc.20.1

• product produced by K. albida [30]. Although rare actinomycetes have been expected to be a source of novel natural products, reports of natural product isolation from rare actinomycetes are limited because of the difficulty in cultivation and genetic manipulation. This study demonstrates that heterologous

• expression of BGCs combined with promoter swapping is a powerful tool for the discovery of new natural products from rare actinomycetes. Conclusion In summary, we identified a cma gene cluster for p-coumaric acid biosynthesis in the K. albida genome. We demonstrated the following two biosynthetic reactions

Unsaturated fatty acids and a prenylated tryptophan derivative from a rare actinomycete of the genus Couchioplanes

• Shun Saito,
• Kanji Indo,
• Naoya Oku,
• Hisayuki Komaki,
• Masashi Kawasaki and
• Yasuhiro Igarashi

Beilstein J. Org. Chem. 2021, 17, 2939–2949, doi:10.3762/bjoc.17.203

• .17.203 Abstract A genome mining survey combined with metabolome analysis of publicly available strains identified Couchioplanes sp. RD010705, a strain belonging to an underexplored genus of rare actinomycetes, as a producer of new metabolites. HPLC-DAD-guided fractionation of its fermentation extracts

• the genus Streptomyces [11], non-Streptomyces actinomycetes, commonly referred to as rare actinomycetes [12], are attracting considerable attention as less tapped taxa for drug discovery. Those within the family Micromonosporaceae, represented by the second most prolific genus Micromonospora following

• same approach to the different family (Pseudonocardiaceae) yielded mycetoindole, a new class of dehydrotryptophan derivative from Actinomycetospora [22]. As part of our continuing studies on the metabolites from underexplored rare actinomycetes, the genus Couchioplanes, another minor genus in

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

• discovery of new natural products. Keywords: DFT-based calculation; oligomycin; peptide; polyketides; Pseudosporangium; rare actinomycetes; Introduction Microbial secondary metabolites have been used as therapeutic drugs [1], veterinary medicines [2], agrochemicals [3], food preservatives/colorings [4][5

• maclafungin [44], the producer of which was not identified, are metabolites of Streptomyces [33][34][35][36] or conventional rare actinomycetes [37][38]. Thus, a novel skeleton and new congeners with distinct structural features were discovered from an underexplored actinomycete of the genus Pseudosporangium

• species demonstrated that the distribution of secondary metabolite biosynthetic genes was not the same even in phylogenetically close species [11]. This finding became our starting point to explore the secondary metabolism in actinomycete genera from which no secondary metabolites were described. “Rare