Table 1 |.

Genetically encoded fluorescent sensors for lactate

Sensor	Binding protein	Species sensed	Affinity (Kd)	Dynamic range	Molecular size (kDa)	FP	Sensor type	Validated in subcellular compartments	Validated in vivo	Validated in clinical samples
FiLa	E. coli LLdR protein	Lactate	~130 μM	~1,500%	47.3	cpYFP	Ratiometric	Cytosol/nucleus/mitochondria	Yes	Human plasma/serum
FiLa-H	E. coli LLdR protein	Lactate	~20 μM	~2,600%	47.3	cpYFP	Ratiometric	Cytosol/nucleus	No	Human plasma/serum/urine
FiLa-La	E. coli LLdR protein	Lactate	~800 μM	~700%	47.3	cpYFP	Ratiometric	Cytosol/nucleus/mitochondria	No	No
Laconic51	E. coli LLdR protein	Lactate; citrate	~8 μM; ~830 μM	~19%	83.9	mTFP/Venus	Ratiometric	Cytosol/nucleus	Yes	No
Green Lindoblum52	E. coli LLdR protein	Lactate	~30 μM	~420%	48.5	GFP	Intensiometric	Cytosol/plasma membrane	No	Mouse pLasma
GEM-IL54	E. coli LLdR protein	Lactate	~661 μM	~87.5%	48.7	sfCFP(1-10)/sfGFP11	Intensiometric	Cytosol	No	No
eLACCO1.1 (ref. 53)	T. thermophilus TTHA0766 protein	Lactate; Ca2+	~3.9 μM	~400%	66.3	cpGFP	Intensiometric	Cytosol/cell surface	No	No
CanlonicSF56	T. thermophilus TTHA0766 protein	Lactate; Ca2+	~300 μM	~190%	65.8	cpGFP	Intensiometric	Cytosol/endoplasmic reticulum	No	No
LiLac55	H. pylori TlpC protein	Lactate	~0.62 mM; ~2.68 mMb	~1 ns (Ax)	57.3	mTurquoise2	Fluorescence lifetime	Cytosol	No	No

Bold indicates desired properties of the sensor.

^aFiLa-L is mutant of FiLa of Low affinity.

^bThe apparent K_d of LiLac is ~0.62 μM at 24 °C and ~2.68 μM at 34 °C.