Development of a new host strain by deletion of biofilm-related genes in Escherichia coli

Abstract

Bacteria can adhere to biotic or abiotic surfaces and form sessile communities called biofilms. Biofilms are problematic in industrial settings, because they shorten lifetime of modules in industrial settings and retard diffusion of nutrients, antibiotics or some other solutes. There are some suggestions for inhibition of biofilm formation, but those method, treatment of biofilm inhibition chemicals and development of new surfaces for protection from biofilm formation, have environmental or cost problems. To overcome those problems in industrial or laboratorial settings, we have developed new host strain, Δ(cur+col+pil), by deletion of biofilm structure-related genes were deleted from the Escherichia coli genome. In Δ(cur+col+pil) mutant strain curli-related genes, type I pili-related genes, and colanic-acid-related genes were deleted. Δ(cur+col+pil) strain has lower adherence property than wildtype MG1655. And its cell concentration is little bit lower than wildtype MG1655 but its planktonic cell concentration is higher than wildtype. And it has higher antibiotic sensitivity to ampicilin, streptomycin, and rifampicin. And we can get higher yield for Pseudomonas flouroscens lipase secretion with Δ(cur+col+pil) mutant strain.