Reducing the variability of antibiotic production in Streptomyces by cultivation in 24-square deepwell plates

Transcriptional regulation of the novobiocin biosynthetic gene cluster

“…Only traces of novobiocin were detected within the first 48 h after inoculation, while the highest novobiocin production rate was observed between 72 and 96 h after inoculation. In contrast, dry cell weight increased between 24 and 72 h after inoculation (Siebenberg et al, 2009), confirming the earlier observation that novobiocin production starts at the transition from growth phase to stationary phase (Kominek, 1972).…”

Two Pathways for Pyrrole Formation in Coumermycin A1 Biosynthesis: The Central Pyrrole Moiety Is Formed From L‐Threonine

“…[13] The culture supernatant was analyzed by HPLC-MS in comparison to cultures without feeding of labeled threonine (Figure 3). The CPM monoamide formed in the feeding experiment showed a strong MS signal with m/z 362 [MÀH] À , in addition to the regular molecular ion (MÀH À = 357, Figure 3).…”

“…The CPM monoamide formed in the feeding experiment showed a strong MS signal with m/z 362 [MÀH] À , in addition to the regular molecular ion (MÀH À = 357, Figure 3). This fragment [MÀH+5] indicated that the four 13 C carbons and the 15 N nitrogen of the labeled lthreonine had been incorporated into the CPM monoamide. The fragmentation pattern of the m/z 362 ion showed m/z 206, that is, the unlabeled aminocoumarin ring, as the most abundant fragment; this demonstrates that the label had been incorporated into the pyrrole rather than into the aminocoumarin moiety.…”

“…One of these genes shows similarity to l-threonine kinase genes. Feeding of [U- 13 C, 15 N]l-threonine and 13 C NMR analysis of the resulting compound unequivocally proved that threonine was incorporated intact into the central pyrrole (19 % enrichment) to provide the heterocyclic nitrogen as well as four of the seven carbons of this moiety. Therefore, this pyrrole is formed via a new, hitherto unknown biosynthetic pathway.…”

Three pathway-specific regulators control streptolydigin biosynthesis in Streptomyces lydicus

“…Streptolydigin production in S. lydicus wild-type or mutant strains grown on R5A medium was analysed by UPLC (Acquity UPLC equipment with a BEH C18 Waters column of 2.16100 mm) and LC-MS (Alliance chromatographic system coupled to a ZQ4000 mass spectrometer and a Symmetry C18 Waters column of 2.16150 mm) (Waters Cromatografía) using procedures previously described (Olano et al, 2009). Cultures in liquid medium were performed using square deepwell plates consisting of 24 wells of 3 ml culture volume each (Siebenberg et al, 2010). Precultures of S. lydicus were prepared in 250 ml baffled Erlenmeyer flasks containing 50 ml TSB medium.…”