Evolutionary engineering and chemical mutagenesis of Propionibacterium acidipropionici for improved propionic acid production from sugarcane-derived saccharides

• Published in: Process biochemistry (1991) Vol. 130; pp. 584 - 594
• Main Authors: Hoffmam, Zaira Bruna, Soares, Lauren Bergmann, de Morais, Edvaldo Rodrigo, Souza, Jaqueline Matsusato, de Andrade, Ana Luisa David, de Jesus, Charles Dayan Farias, Martins, Bianca, Bonomi, Antonio, Ruller, Roberto, Ward, Richard John, Ienczak, Jaciane Lutz
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-07-2023
• Subjects: Ethyl methanesulfonate; Propionibacterium acidipropionici; Propionic fermentation; Strain improvement; Sugarcane; Propionibacterium acidipropionici; Strain improvement; Ethyl methanesulfonate; Sugarcane; Propionic fermentation
• ISSN: 1359-5113; 1873-3298
• DOI: 10.1016/j.procbio.2023.05.022

Propionic acid (PA) is a 3-carbon carboxylic acid widely used in the chemical, food and pharmaceutical industries. Current production of PA is primarily via petrochemical routes and alternative sources using renewable feedstocks are desirable. The goal of the present study was to develop bacterial strains for efficient PA production by fermentation of sugarcane-derived saccharides in inverted sugarcane syrup. Adaptive evolution and random chemical mutagenesis of Propionibacterium acidipropionici were individually evaluated. Although evolutionary engineering proved to be a suitable strategy for producing strains tolerant to acid stress, chemical mutagenesis coupled with a novel screening methodology proved to be a superior strategy for strain improvement. The selected strain presented high PA productivity (0.55 g L−1 h−1) and titer (40 g L−1) in relation to the parental strain (0.38 g L−1 h−1 and 27 g L−1, respectively), in fermentations using inverted sugarcane syrup.
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•P. acidipropionici is more tolerant to propionate than other propionibacteria.•Acid tolerance did not correlate with higher propionate production.•Random mutagenesis coupled to rounds of selection results in improved strains.•The M8 strain ferments high test molasses with a 60% production rate improvement.