Fig. 3: Selection of efficient enzymes for biosynthesis of 3HP in H. bluephagenesis.

a Construction of the plasmids to express enzymes from different species. Following plasmids were constructed: plasmid p90 expressing adhP gene with a His-tag on C-terminal, p91 expressing aldD_Hb gene with a His-tag on C-terminal, p92 expressing dhaT_Pp gene with a His-tag on C-terminal and p98 expressing aldD_Pp gene with a His-tag on N-terminal. The aldH gene, with a His-tag on N-terminal, was amplified via PCR using E. coli genomic DNA as a template and cloned into the p58 by replacing the aldD_Hb gene. This plasmid is labeled as p99. The dhaT_Kp or puuC gene, with a His-tag, was amplified via PCR using K. pneumoniae DSMZ 2026 genomic DNA as a template and cloned into the p58 by replacing the adhP or aldD_Hb gene. These plasmids were labeled as p95 and p100. 3HP production of different alcohol dehydrogenases (b), and different aldehyde dehydrogenases (c). Cells were grown in the defined minimal medium containing 20 g L⁻¹ glucose, 20 g L⁻¹ 1,3-propanediol, and 3 g L⁻¹ acetic acid. All titers were obtained after 48 h cultivation at 200 r.p.m. and 37 °C. The initial pH of all shake-flask studies was 9. All data represent the mean of n = 2 biologically independent. The comparation of the various alcohol dehydrogenases oxidative activities (d), and various aldehyde dehydrogenases activities (e) in a purified enzyme. All data represent the mean of n = 3 biologically independent samples and error bars show s.d.