Characterization of Highly Ferulate-Tolerant Acinetobacter baylyi ADP1 Isolates by a Rapid Reverse Engineering Method
Jin Luo, Emily A. McIntyre, Stacy R. Bedore, Ville Santala, Ellen L. Neidle, Suvi Santala
Abstract
Microbial conversion of lignin-enriched streams is a promising approach for lignin valorization. However, the lignin-derived aromatic compounds are toxic to cells at relevant concentrations. Although adaptive laboratory evolution (ALE) is a powerful approach to develop more tolerant strains, it is typically laborious to identify the mechanisms underlying phenotypic improvement. We employed Acinetobacter baylyi ADP1, an aromatic-compound-degrading strain that may be useful for biotechnology. The natural competence and high recombination efficiency of this strain can be exploited for critical applications, such as the breakdown of lignin and plastics and abundant polymers composed of aromatic subunits. The natural transformability of this bacterium enabled us to develop a novel approach for rapid screening of advantageous mutations from ALE-derived, aromatic-tolerant, ADP1-derived strains. We clarified the mechanisms and genetic targets for improved tolerance toward common lignin-derived aromatic compounds. This study facilitates metabolic engineering for lignin valorization.