Streptomyces are Gram-positive, filamentous bacteria belonging to the group
actinomycetes. This bacterium is important to the modern industrial world because of
the presence of 20-50 biosynthetic gene clusters (BGCs). BGCs contain the genes for
the production of industrially important natural products (NP), which includes
antibiotics, anti-tumor drugs, anti-depressants, etc., naturally originated from this
microorganism. Strain improvement is required to enhance the production of these NP
in Streptomyces. Different methods have been used to enhance NP production and
strain improvement. In this chapter, we will be discussing strain improvement of
Streptomyces species by different genome editing tools. The information, which is put
together, includes the basic techniques used for genome editing to the most advanced
CRISPR/Cas system associated genome editing in Streptomyces (PCR targeting
system, Cre-loxP recombination system, I SceI meganuclease promoted recombination
system and CRISPR/Cas system). The authors have discussed about multiplex
automated genome editing (MAGE) tool associated with CRISPR/Cas system.
Keywords: Bacterial gene clusters, CRISPR/Cas, Genetic manipulations, Metabolic engineering, Recombination system, Streptomyces.
