Previous Article | Next Article ![]()
Applied and Environmental Microbiology, May 2008, p. 2834-2840, Vol. 74, No. 9
0099-2240/08/$08.00+0 doi:10.1128/AEM.02800-07
Copyright © 2008, American Society for Microbiology. All Rights Reserved.
,
National Food Research Institute, Tsukuba, Ibaraki 305-8642, Japan
Received 11 December 2007/ Accepted 23 February 2008
We recently described a new method to activate antibiotic production in bacteria by introducing a mutation conferring resistance to a drug such as streptomycin, rifampin, paromomycin, or gentamicin. This method, however, enhanced antibiotic production by only up to an order of magnitude. Working with Streptomyces coelicolor A3(2), we established a method for the dramatic activation of antibiotic production by the sequential introduction of multiple drug resistance mutations. Septuple and octuple mutants, C7 and C8, thus obtained by screening for resistance to seven or eight drugs, produced huge amounts (1.63 g/liter) of the polyketide antibiotic actinorhodin, 180-fold higher than the level produced by the wild type. This dramatic overproduction was due to the acquisition of mutant ribosomes, with aberrant protein and ppGpp synthesis activity, as demonstrated by in vitro protein synthesis assays and by the abolition of antibiotic overproduction with relA disruption. This new approach, called "ribosome engineering," requires less time, cost, and labor than other methods and may be widely utilized for bacterial strain improvement.
Published ahead of print on 29 February 2008.
Supplemental material for this article may be found at http://aem.asm.org/.
This article has been cited by other articles:
Copyright © 2009 by the American Society for Microbiology. For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»