Table 2.

reporter genes for Borrelia

REPORTER	APPLICATION(S)	LIMITATION(S)	REFERENCE(S)
Borrelia burgdorferi
cat (chloramphenicol acetyl transferase)	in vitro gene expression	requires radioactivity or ELISA	(Sohaskey et al., 1997; Alverson et al., 2003)
lacZ (β-galactosidase)	in vitro gene expression; colorimetric detection in liquid and solid medium; easy blue/white screening	requires X-gal substrate	(Hayes et al., 2010)
FLUORESCENT REPORTERS (listed below)	in vitro and in vivo gene expression; cellular localization of fusion proteins; in vivo imaging of individual spirochetes in ticks and mice	fluorescence parameters vary among reporters and alleles; not all reporters tested for in vivo applications
GFP, mEGFP. msfGFP (Green Fluorescent Protein)			(Carroll et al., 2003; Eggers et al., 2004; Moriarty et al., 2008; Dunham-Ems et al., 2009; Takacs et al., 2018)
YFP, mCitrine, msfYFP (Yellow Fluorescent Protein)			(Eggers et al., 2002; Takacs et al., 2018)
CFP, mCerulean, msfCFP (Cyan Fluorescent Protein)			(Eggers et al., 2002; Takacs et al., 2018)
mRFP, mCherry (Red Fluorescent Protein)			(Schulze and Zuckert, 2006; Takacs et al., 2018)
dTomato (Orange Fluorescent Protein)			(Lee et al., 2010)