Markerless gene deletion system for sphingomonads

Abstract

Here, we suggest that natural streptomycin resistance of many sphingomonads resides within rpsL. We constructed a dominant, streptomycin-sensitive rpsL allele and demonstrated its use as a counterselection marker in several sphingomonads. An rpsLbased markerless gene deletion system was developed and validated by deleting four genes in Sphingomonas sp. strain Fr1. © 2012, American Society for Microbiology.