In situ mutagenesis and chemotactic selection of microorganisms in a diffusion gradient chamber

• Published in: Applied biochemistry and biotechnology Vol. 70-72; no. 1; pp. 905 - 918
• Main Authors: MIKOLA, M. R, WIDMAN, M. T, WORDEN, R. M
• Format: Conference Proceeding Journal Article
• Language: English
• Published: Heidelberg Springer 01-03-1998; Springer Nature B.V
• Subjects: 3-Deoxy-7-Phosphoheptulonate Synthase - analysis; Biological and medical sciences; Biotechnology; Chemotaxis; Diffusion Chambers, Culture; Escherichia coli - enzymology; Escherichia coli - genetics; Escherichia coli - radiation effects; Fundamental and applied biological sciences. Psychology; Genetic technics; Glucose - chemistry; Mathematical models; Methods. Procedures. Technologies; Microorganisms; Models, Theoretical; Mutagenesis; Mutagenesis, Site-Directed; Mutant screening; Prokaryotes; Ultraviolet Rays; Resistance; Tyrosine; Mutagenesis; Escherichia coli; Selection; Bacteria; Inhibitor; Mutation; Method; Mathematical model; Chemotaxis; Enterobacteriaceae
• ISSN: 0273-2289; 1559-0291
• DOI: 10.1007/BF02920201

A new method has been developed to rapidly generate and select microbial strains having increased resistance to an inhibitory compound. The method combines in situ mutagenesis with use of a continuous gradient of the inhibitor to sort cells according to their resistance levels. Microbial chemotaxis is induced to accelerate the selection process. The method was used to develop a strain of E. coli having a feedback-resistant DAHP synthase enzyme. An unsteady-state mathematical model of the process has been developed. The model, that can reproduce key trends observed experimentally, was used to explore the effects of chemotaxis on the efficiency of the selection process.