MOESM1 of Identification and utilization of two important transporters: SgvT1 and SgvT2, for griseoviridin and viridogrisein biosynthesis in Streptomyces griseoviridis

Additional file 1: Figure S1. The multiple alignment of SgvT1/T3 with other transporters. Figure S2. The multiple alignment of SgvT2 with other transporters. Figures S3–S5. The inactivation of sgvT1-T3. Figure S6–S8. HPLC analyses of the fermentation extract of Wild-type & ΔsgvT1-T3. Figure S9. HPLC analyses of the fermentation extract of WT::sgvT1–T2. Figure S10. The HPLC standard curve of GV/ VG. Figure S11. HPLC analyses of fermentation extract of complemented mutants. Table S1. Primer pairs used for PCR-targeting of sgvT1–T3. Table S2. Primers used for PCR confirmation of double-crossover mutants. Table S3. Primer pairs used for complementation of sgvT1–T3. Table S4. Primer pairs used for RT-PCR. Table S5. Primer pairs used for qPCR. Table S6. Quantitative analysis of GV/VG production

Discovery of a New Family of Dieckmann Cyclases Essential to Tetramic Acid and Pyridone-Based Natural Products Biosynthesis

Bioinformatic analyses indicate that TrdC, SlgL, LipX₂, KirHI, and FacHI belong to a group of highly homologous proteins involved in biosynthesis of actinomycete-derived tirandamycin B, streptolydigin, α-lipomycin, kirromycin, and factumycin, respectively. However, assignment of their biosynthetic roles has remained elusive. Gene inactivation and complementation, <i>in vitro</i> biochemical assays with synthetic analogues, point mutations, and phylogenetic tree analyses reveal that these proteins represent a new family of Dieckmann cyclases that drive tetramic acid and pyridone scaffold biosynthesis

Identification of the Biosynthetic Gene Cluster for the Anti-infective Desotamides and Production of a New Analogue in a Heterologous Host

The desotamides (DSAs) are potent antibacterial cyclohexapeptides produced by <i>Streptomyces scopuliridis</i> SCSIO ZJ46. We have identified the 39-kb <i>dsa</i> biosynthetic gene cluster by whole-genome scanning. Composed of 17 open reading frames, the cluster codes for four nonribosomal peptide synthetases and associated resistance, transport, regulatory, and precursor biosynthesis proteins. Heterologous expression of the <i>dsa</i> gene cluster in <i>S. coelicolor</i> M1152 afforded desotamides A and B and the new desotamide G. Cluster identification and its demonstrated amenability to heterologous expression provide the foundation for future mechanistic studies as well as the generation of new and potentially clinically significant DSA analogues

Enzymatic Synthesis of GDP-α‑l‑fucofuranose by MtdL and Hyg20

Two mutases, MtdL and Hyg20, are reported. Both are able to functionally drive the biosynthesis of GDP-α-l-fucofuranose. Both enzymes catalyze similar functions, catalytically enabling the bidirectional reaction between GDP-β-l-fucopyranose and GDP-α-l-fucofuranose using only divalent cations as cofactors. This realization is but one of a number of important insights into fucofuranose biosynthesis presented herein

Deciphering the Biosynthetic Origin of l-<i>allo</i>-Isoleucine

The nonproteinogenic amino acid l-<i>allo</i>-isoleucine (l-<i>allo</i>-Ile) is featured in an assortment of life forms comprised of, but not limited to, bacteria, fungi, plants and mammalian systems including <i>Homo sapiens</i>. Despite its ubiquity and functional importance, the specific origins of this unique amino acid have eluded characterization. In this study, we describe the discovery and characterization of two enzyme pairs consisting of a pyridoxal 5′-phosphate (PLP)-linked aminotransferase and an unprecedented isomerase synergistically responsible for the biosynthesis of l-<i>allo</i>-Ile from l-isoleucine (l-Ile) in natural products. DsaD/DsaE from the desotamide biosynthetic pathway in <i>Streptomyces scopuliridis</i> SCSIO ZJ46, and MfnO/MfnH from the marformycin biosynthetic pathway in <i>Streptomyces drozdowiczii</i> SCSIO 10141 drive l-<i>allo</i>-Ile generation in each respective system. In vivo gene inactivations validated the importance of the DsaD/DsaE pair and MfnO/MfnH pair in l-<i>allo</i>-Ile unit biosynthesis. Inactivation of PLP-linked aminotransferases DsaD and MfnO led to significantly diminished desotamide and marformycin titers, respectively. Additionally, inactivation of the isomerase genes <i>dsaE</i> and <i>mfnH</i> completely abolished production of all l-<i>allo</i>-Ile-containing metabolites in both biosynthetic pathways. Notably, in vitro biochemical assays revealed that DsaD/DsaE and MfnO/MfnH each catalyze a bidirectional reaction between l-<i>allo</i>-Ile and l-Ile. Site-directed mutagenesis experiments revealed that the enzymatic reaction involves a PLP-linked ketimine intermediate and uses an arginine residue from the <i>C</i>-terminus of each isomerase to epimerize the amino acid β-position. Consequently, these data provide important new insight into the origins of l-<i>allo</i>-Ile in natural products with medicinal potential and illuminate new possibilities for biotool development

Biosynthesis of the Anti-infective Marformycins Featuring Pre-NRPS Assembly Line <i>N</i>‑Formylation and <i>O</i>‑Methylation and Post-Assembly Line <i>C</i>‑Hydroxylation Chemistries

The biosynthetic gene cluster governing production of anti-infective marformycins was identified from deep sea-derived <i>Streptomyces drozdowiczii</i> SCSIO 10141. The putative <i>mfn</i> gene cluster (45 kb, 20 orfs) was found to encode six NRPSs and related proteins for cyclodepsipeptide core construction (<i>mfnCDEFKL</i>), a methionyl-tRNA formyltransferase (<i>mfnA</i>), a SAM-dependent methyltransferase (<i>mfnG</i>), and a cytochrome P450 monooxygenase for piperazic acid moiety hydroxylation (<i>mfnN</i>); notably, only MfnN uses an intact cyclodepsipeptide intermediate as its substrate

Abyssomicin Monomers and Dimers from the Marine-Derived <i>Streptomyces koyangensis</i> SCSIO 5802

Three new abyssomicin monomers designated neoabyssomicins D (<b>1</b>), E (<b>2</b>), and A2 (<b>3</b>) and the two dimeric neoabyssomicins F (<b>4</b>) and G (<b>5</b>) were discovered from the marine-derived <i>Streptomyces koyangensis</i> SCSIO 5802, and their structures rigorously elucidated. Neoabyssomicin D (<b>1</b>) possesses an unprecedented 8/5/5/7 ring skeleton, the biosynthesis of which (as well as <b>2</b>) is proposed herein. Additionally, dimeric agents <b>4</b> and <b>5</b> were found to be active against methicillin-resistant <i>Staphylococcus aureus</i> and vesicular stomatitis virus, respectively

Abyssomicin Monomers and Dimers from the Marine-Derived <i>Streptomyces koyangensis</i> SCSIO 5802

Three new abyssomicin monomers designated neoabyssomicins D (<b>1</b>), E (<b>2</b>), and A2 (<b>3</b>) and the two dimeric neoabyssomicins F (<b>4</b>) and G (<b>5</b>) were discovered from the marine-derived <i>Streptomyces koyangensis</i> SCSIO 5802, and their structures rigorously elucidated. Neoabyssomicin D (<b>1</b>) possesses an unprecedented 8/5/5/7 ring skeleton, the biosynthesis of which (as well as <b>2</b>) is proposed herein. Additionally, dimeric agents <b>4</b> and <b>5</b> were found to be active against methicillin-resistant <i>Staphylococcus aureus</i> and vesicular stomatitis virus, respectively

Abyssomicin Monomers and Dimers from the Marine-Derived <i>Streptomyces koyangensis</i> SCSIO 5802

Three new abyssomicin monomers designated neoabyssomicins D (<b>1</b>), E (<b>2</b>), and A2 (<b>3</b>) and the two dimeric neoabyssomicins F (<b>4</b>) and G (<b>5</b>) were discovered from the marine-derived <i>Streptomyces koyangensis</i> SCSIO 5802, and their structures rigorously elucidated. Neoabyssomicin D (<b>1</b>) possesses an unprecedented 8/5/5/7 ring skeleton, the biosynthesis of which (as well as <b>2</b>) is proposed herein. Additionally, dimeric agents <b>4</b> and <b>5</b> were found to be active against methicillin-resistant <i>Staphylococcus aureus</i> and vesicular stomatitis virus, respectively

Abyssomicin Monomers and Dimers from the Marine-Derived <i>Streptomyces koyangensis</i> SCSIO 5802

Three new abyssomicin monomers designated neoabyssomicins D (<b>1</b>), E (<b>2</b>), and A2 (<b>3</b>) and the two dimeric neoabyssomicins F (<b>4</b>) and G (<b>5</b>) were discovered from the marine-derived <i>Streptomyces koyangensis</i> SCSIO 5802, and their structures rigorously elucidated. Neoabyssomicin D (<b>1</b>) possesses an unprecedented 8/5/5/7 ring skeleton, the biosynthesis of which (as well as <b>2</b>) is proposed herein. Additionally, dimeric agents <b>4</b> and <b>5</b> were found to be active against methicillin-resistant <i>Staphylococcus aureus</i> and vesicular stomatitis virus, respectively