Cloning and expression vectors for a Gram-positive host, Streptomyces lividans.
The choice of an expression system for the meta-genomic DNA of interest is of vital importance for the detection of any particular gene or gene cluster. Most of the screens to date have used the Gram-negative bacterium Escherichia coli as a host for the meta-genomic gene libraries. However, the use of E. coli introduces a potential host bias since only 40% of the enzymatic activities may be readily recovered by random cloning in E. coli (Gabor et al., Environ Microbiol 6:879-886, 2004). To recover some of the remaining 60%, alternative cloning hosts such as Streptomyces spp. have been used (Lorenz and Eck, Nat Rev Microbiol 3:510-516, 2005). Streptomycetes are high-GC Gram-positive bacteria that belong to the Actinomycetales, and they have been studied extensively in the last 10 years as an alternative expression system (reviewed in Vrancken and Anné, Future Microbiol 4:181-188, 2009). Streptomyces is extremely well suited for the expression of DNA from other actinomycetes and genomes of high GC content (Wang et al., Org Lett 2:2401-2404, 2000). Furthermore, due to its high innate secretion capacity, it can be a superior system than E. coli for the production of many extra-cellular proteins.
Vrancken
Kristof
K
Department of Microbiology and Immunology, Rega Institute for Medical Research, K.U. Leuven, Leuven, Belgium.
Van Mellaert
Lieve
L
Anné
Jozef
J
D003001:Cloning, Molecular / Q000379:methods; D004926:Escherichia coli / Q000235:genetics; D005822:Genetic Vectors; D056186:Metagenomics / Q000379:methods; D048170:Streptomyces lividans / Q000166:cytology / Q000235:genetics*