Fig. 6: Acs is required for morphological development of S. roseosporus.

a Acs is required for Streptomyces morphological development. The wild type (WT), the Δacs mutant and the acs-overexpression strain (WT + ermEp*-acs) were patched on the R5 medium, incubated for 7 days and photographed. b Acs is required for intracellular crotonyl-CoA production. The crotonyl-CoA was examined on HPLC-MS from the cell lysate of WT and the Δacs mutant, which have been fermented for 24 and 48 h, respectively. The data were from three independent repeats and the significant difference was presented. Statistical significance was determined by Student’s t test, n = 3. In all panels error bars show SEM, and *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001. c Crotonylation mimic mutation of Acs abolished its enzymatic activity. Both wild type Acs protein and the Acs variant with six mutations of Lys to Asn were purified from E. coli, and their activity of acetyl-CoA synthetase was quantitatively examined. The data were from three independent repeats and significant difference was shown. Statistical significance was determined by Student’s t test, n = 6. In all panels error bars show SEM, and *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001.