title: Regulatory and metabolic network of rhamnolipid biosynthesis: traditional and advanced engineering towards biotechnological production.
abstract: During the last decade, the demand for economical and sustainable bioprocesses replacing petrochemical-derived products has significantly increased. Rhamnolipids are interesting biosurfactants that might possess a broad industrial application range. However, despite of 60 years of research in the area of rhamnolipid production, the economic feasibility of these glycolipids is pending. Although the biosynthesis and regulatory network are in a big part known, the actual incidents on the cellular and process level during bioreactor cultivation are not mastered. Traditional engineering by random and targeted genetic alteration, process design, and recombinant strategies did not succeed by now. For enhanced process development, there is an urgent need of in-depth information about the rhamnolipid production regulation during bioreactor cultivation to design knowledge-based genetic and process engineering strategies. Rhamnolipids are structurally comparable, simple secondary metabolites and thus have the potential to become instrumental in future secondary metabolite engineering by systems biotechnology. This review summarizes current knowledge about the regulatory and metabolic network of rhamnolipid synthesis and discusses traditional and advanced engineering strategies performed for rhamnolipid production improvement focusing on Pseudomonas aeruginosa. Finally, the opportunities of applying the systems biotechnology toolbox on the whole-cell biocatalyst and bioprocess level for further rhamnolipid production optimization are discussed.
authors.affiliation: Institute of Process Engineering in Life Sciences, Section II: Technical Biology, Karlsruhe Institute of Technology (KIT), Engler-Bunte-Ring 1, 76131 Karlsruhe, Germany. markus.mueller2@kit.edu
authors.forename: Markus Michael
authors.initials: MM
authors.lastname: Müller
authors.forename: Rudolf
authors.initials: R
authors.lastname: Hausmann
mesh_terms: D001709:Biotechnology / Q000379:methods*; D015964:Gene Expression Regulation, Bacterial; D005818:Genetic Engineering; D006017:Glycolipids / Q000096:biosynthesis* / Q000378:metabolism; D053858:Metabolic Networks and Pathways; D011550:Pseudomonas aeruginosa / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D013501:Surface-Active Agents / Q000378:metabolism
chemical_list: D006017:Glycolipids; D013501:Surface-Active Agents; C418382:rhamnolipid