Limits...
Pleiotropic regulatory genes bldA, adpA and absB are implicated in production of phosphoglycolipid antibiotic moenomycin.

Makitrynskyy R, Ostash B, Tsypik O, Rebets Y, Doud E, Meredith T, Luzhetskyy A, Bechthold A, Walker S, Fedorenko V - Open Biol (2013)

Bottom Line: Unlike the majority of actinomycete secondary metabolic pathways, the biosynthesis of peptidoglycan glycosyltransferase inhibitor moenomycin in Streptomyces ghanaensis does not involve any cluster-situated regulators (CSRs).Our work highlights an underappreciated strategy for secondary metabolism regulation, in which the interaction between structural genes and pleiotropic regulators is not mediated by CSRs.This strategy might be relevant for a growing number of CSR-free gene clusters unearthed during actinomycete genome mining.

View Article: PubMed Central - PubMed

Affiliation: Department of Genetics and Biotechnology, Ivan Franko National University of Lviv, Hrushevskoho st. 4, Lviv 79005, Ukraine.

ABSTRACT
Unlike the majority of actinomycete secondary metabolic pathways, the biosynthesis of peptidoglycan glycosyltransferase inhibitor moenomycin in Streptomyces ghanaensis does not involve any cluster-situated regulators (CSRs). This raises questions about the regulatory signals that initiate and sustain moenomycin production. We now show that three pleiotropic regulatory genes for Streptomyces morphogenesis and antibiotic production-bldA, adpA and absB-exert multi-layered control over moenomycin biosynthesis in native and heterologous producers. The bldA gene for tRNA(Leu)UAA is required for the translation of rare UUA codons within two key moenomycin biosynthetic genes (moe), moeO5 and moeE5. It also indirectly influences moenomycin production by controlling the translation of the UUA-containing adpA and, probably, other as-yet-unknown repressor gene(s). AdpA binds key moe promoters and activates them. Furthermore, AdpA interacts with the bldA promoter, thus impacting translation of bldA-dependent mRNAs-that of adpA and several moe genes. Both adpA expression and moenomycin production are increased in an absB-deficient background, most probably because AbsB normally limits adpA mRNA abundance through ribonucleolytic cleavage. Our work highlights an underappreciated strategy for secondary metabolism regulation, in which the interaction between structural genes and pleiotropic regulators is not mediated by CSRs. This strategy might be relevant for a growing number of CSR-free gene clusters unearthed during actinomycete genome mining.

Show MeSH

Related in: MedlinePlus

Levels of nosokomycin B1 production by various streptomycetes expressing cosmid moeno38-5. Column labels: M145, J3410 and M851—wild-type, rnc (absB)-minus and bldH (adpA)-minus mutants of S. coelicolor, respectively; 1326 and J1725—wild-type and bldA  mutant of S. lividans, respectively.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3814723&req=5

RSOB130121F8: Levels of nosokomycin B1 production by various streptomycetes expressing cosmid moeno38-5. Column labels: M145, J3410 and M851—wild-type, rnc (absB)-minus and bldH (adpA)-minus mutants of S. coelicolor, respectively; 1326 and J1725—wild-type and bldA mutant of S. lividans, respectively.

Mentions: To determine the level of moenomycins biosynthesis on a ΔabsB-background, a cosmid moeno38-5 [10] carrying the main part of moe cluster 1 and directing the production of nosokomycin B2 (NoB2) was introduced into S. coelicolorΔabsB strain J3410 [41]. S. coelicolor J3410 moeno38-5+ was grown in parallel with a control strain S. coelicolor M145 moeno38-5+ and NoB2 was quantified. On average, J3410 moeno38-5+ accumulated 20% less biomass than M145 moeno38-5+ and produced three times less NoB2 compared with the control strain (figure 8). These data correlate with the results of reporter experiments, where we observed a 1.5-fold decrease in moeE5 transcription in a ΔabsBgh strain compared with a control M145 strain (data not shown). Our results suggest that the AbsB RNase III-mediated regulatory pathway is important for moenomycin production even in other streptomycete heterologous hosts.Figure 8.


Pleiotropic regulatory genes bldA, adpA and absB are implicated in production of phosphoglycolipid antibiotic moenomycin.

Makitrynskyy R, Ostash B, Tsypik O, Rebets Y, Doud E, Meredith T, Luzhetskyy A, Bechthold A, Walker S, Fedorenko V - Open Biol (2013)

Levels of nosokomycin B1 production by various streptomycetes expressing cosmid moeno38-5. Column labels: M145, J3410 and M851—wild-type, rnc (absB)-minus and bldH (adpA)-minus mutants of S. coelicolor, respectively; 1326 and J1725—wild-type and bldA  mutant of S. lividans, respectively.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3814723&req=5

RSOB130121F8: Levels of nosokomycin B1 production by various streptomycetes expressing cosmid moeno38-5. Column labels: M145, J3410 and M851—wild-type, rnc (absB)-minus and bldH (adpA)-minus mutants of S. coelicolor, respectively; 1326 and J1725—wild-type and bldA mutant of S. lividans, respectively.
Mentions: To determine the level of moenomycins biosynthesis on a ΔabsB-background, a cosmid moeno38-5 [10] carrying the main part of moe cluster 1 and directing the production of nosokomycin B2 (NoB2) was introduced into S. coelicolorΔabsB strain J3410 [41]. S. coelicolor J3410 moeno38-5+ was grown in parallel with a control strain S. coelicolor M145 moeno38-5+ and NoB2 was quantified. On average, J3410 moeno38-5+ accumulated 20% less biomass than M145 moeno38-5+ and produced three times less NoB2 compared with the control strain (figure 8). These data correlate with the results of reporter experiments, where we observed a 1.5-fold decrease in moeE5 transcription in a ΔabsBgh strain compared with a control M145 strain (data not shown). Our results suggest that the AbsB RNase III-mediated regulatory pathway is important for moenomycin production even in other streptomycete heterologous hosts.Figure 8.

Bottom Line: Unlike the majority of actinomycete secondary metabolic pathways, the biosynthesis of peptidoglycan glycosyltransferase inhibitor moenomycin in Streptomyces ghanaensis does not involve any cluster-situated regulators (CSRs).Our work highlights an underappreciated strategy for secondary metabolism regulation, in which the interaction between structural genes and pleiotropic regulators is not mediated by CSRs.This strategy might be relevant for a growing number of CSR-free gene clusters unearthed during actinomycete genome mining.

View Article: PubMed Central - PubMed

Affiliation: Department of Genetics and Biotechnology, Ivan Franko National University of Lviv, Hrushevskoho st. 4, Lviv 79005, Ukraine.

ABSTRACT
Unlike the majority of actinomycete secondary metabolic pathways, the biosynthesis of peptidoglycan glycosyltransferase inhibitor moenomycin in Streptomyces ghanaensis does not involve any cluster-situated regulators (CSRs). This raises questions about the regulatory signals that initiate and sustain moenomycin production. We now show that three pleiotropic regulatory genes for Streptomyces morphogenesis and antibiotic production-bldA, adpA and absB-exert multi-layered control over moenomycin biosynthesis in native and heterologous producers. The bldA gene for tRNA(Leu)UAA is required for the translation of rare UUA codons within two key moenomycin biosynthetic genes (moe), moeO5 and moeE5. It also indirectly influences moenomycin production by controlling the translation of the UUA-containing adpA and, probably, other as-yet-unknown repressor gene(s). AdpA binds key moe promoters and activates them. Furthermore, AdpA interacts with the bldA promoter, thus impacting translation of bldA-dependent mRNAs-that of adpA and several moe genes. Both adpA expression and moenomycin production are increased in an absB-deficient background, most probably because AbsB normally limits adpA mRNA abundance through ribonucleolytic cleavage. Our work highlights an underappreciated strategy for secondary metabolism regulation, in which the interaction between structural genes and pleiotropic regulators is not mediated by CSRs. This strategy might be relevant for a growing number of CSR-free gene clusters unearthed during actinomycete genome mining.

Show MeSH
Related in: MedlinePlus