Fig. 5: The effect of programmed lysis system on butyrate production.
From: Reprogramming microbial populations using a programmed lysis system to improve chemical production
a Schematic of the butyrate biosynthetic from fatty acid pathway and process in the fermentation of engineered population POP8. Each gene encodes the following: FadL, long-chain fatty acid outer membrane porin; FadD, fatty acyl-CoA synthetase; FadK, short chain acyl-CoA synthetase; FadE, acyl-CoA dehydrogenase; FadB, α component of the fatty acid oxidation complex; FadJ, α component of the anaerobic fatty acid oxidation complex; FadA, β component of the fatty acid oxidation complex; atoB, acetoacetyl-CoA thiolase; hbd, 3-hydroxybutyryl-CoA dehydrogenase; crt, 3-hydroxybutyryl-CoA dehydratase; ter, trans-enoyl-CoA reductase; tesB, acyl-CoA thioesterase II. b The effect of programmed lysis system on producing butyrate. POP6 consists of strain BUT001; POP7 consists of strain BUT002 and strain BUT004; POP8 consists of strain BUT003 and strain BUT004; POP9 consists of strain BUT004. Plus (+) indicates that the corresponding gene or system was introduced. Minus (−) indicates that the corresponding gene was knocked out. Wave (~) indicates that the corresponding gene remained the same. FadR, GntR family transcriptional regulator, a negative regulator for fad regulon and positive regulator of fabA; PTA, phosphate acetyltransferase; ACK phosphate acetyltransferase; ACS, medium-chain acyl-CoA synthetase. (P values = 0.000425; 0.000168; 0.000057; 0.000185; 0.002112;0.000254.) c pH-stat fed-batch culture of POP8 in a 5-L bioreactor. Stages I, II, III were multiple stages during fermentation. (P value = 0.000002). d PI staining was used to detect mortality ratios in fermentation broth at different times. The percentage of fluorescence intensity represented the mortality ratio. The fluorescence intensity of living cells was less than 103, and that of dead cells was more than 103. For each sample, at least 20,000 counts were recorded using a 0.5 mL/s flow rate. Values are shown as mean ± s.d. from three (n = 3) biological replicates. Two-tailed t tests were used to determine statistical significance. Statistical significance was indicated as *P < 0.05, ** for P < 0.01 and *** for P < 0.001, respectively. Source data are provided as a Source Data file.
