A DNA Part Library for Reliable Engineering of the Emerging Model Nematode Symbiotic Bacterium Xenorhabdus griffiniae HGB2511.

Xenorhabdus griffiniae is a bacterium that lives inside the intestine of the entomopathogenic nematode Steinernema hermaphroditum and partners with the nematode to infect and kill insect larvae in soil. The construction of gene circuits, such as reporters, in X. griffiniae would provide tools to study and better understand the symbiotic relationship it has with its host. However, because X. griffiniae is not a model organism, information about gene circuit construction in X. griffiniae is limited. We developed and characterized a DNA part library similar to the CIDAR MoClo extension library for E. coli to allow more efficient construction of genetic circuits in X. griffiniae. TurboRFP expressing strains with different constitutive Anderson promoters and different ribosome binding sites (RBS) were constructed to quantify promoter and RBS strengths in X. griffiniae. Furthermore, two fluorescent proteins sfGFP and sfYFP as well as the bioluminescent luxCDABE operon were added to the part library and successfully expressed in X. griffiniae. We then used the characterized parts of the cell to build and characterize IPTG inducible constructs.