TABLE 1.

Kinetic parameters of tyrosine-adenylating enzymes in the presence of MbtH-like proteins

Unless indicated otherwise, proteins were expressed in an E. coli strain in which the mbtH-like gene ybdZ has been deleted. Tyrosine-adenylating enzymes and MbtH-like proteins were mixed in a molar ratio of 1:1.2. The reaction velocities determined at different tyrosine concentrations and the statistical variation of the parameters are depicted in supplemental Fig. S3.

	Km for l-Tyr	kcat	kcat/Km
	μm	s−1	s−1m−1
NovH alone	275	0.079	290
NovH alone, expressed in ybdZ+E. coli strain	1278	0.120	94
NovH + CloY	277	0.438	1580
CloH + CloY	186	0.497	2670
SimH + SimY	164	1.01	6180
Pcza361.18 + Orf1van	85	1.91	22,200