TABLE 2.

PL and PN kinase specific activities in strains overexpressing the PdxY and PdxK proteins and in pdxK, pdxY, pdxY pdxK, and pdxH mutants^a

Strain	Genotype or description	PL kinase sp act (pmol of PLP formed/min/mg of protein)b	PN kinase sp act (pmol of PNP formed/min/mg of protein)b
TX3977c	JM109(pUC19)	45 ± 9	ND
TX3981c	JM109(pTX608 pdxY+)	371 ± 58	ND
TX4002c	JM109(pTX618 pdxY+)	488 ± 21	ND
NU426d	pdxB+ pdxK+ pdxY+ parent	72 ± 6	74 ± 16
NU402e	pdxB pdxK+ pdxY+	76 ± 15	75 ± 16
TX4015f	pdxB pdxK+ pdxY+	74 ± 6	86 ± 3
TX3634e	pdxB pdxK pdxY+	80 ± 5	4 ± 1
TX4022f	pdxB pdxK+ pdxY	26 ± 4	82 ± 6
TX4024f	pdxB pdxK pdxY	16 ± 1	1.5 ± 0.2
TX3636e	TX3634(pTX485 pdxK+)	270 ± 41	320 ± 13
TX4037c,f	TX3634(pTX608 pdxY+)	ND	57 ± 6
NU816g	pdxB+ pdxK+ pdxY+ pdxH+ parent	63 ± 8	ND
TX2768g	NU816 pdxH::ΩCmr	47 ± 4	ND

^aSee Materials and Methods for growth conditions and description of PL and PN kinase assays. 

^bAll values were determined by duplicate or triplicate assays of two or more independent cultures. Experimental errors are expressed as standard errors of the mean. ND, not determined. 

^cIPTG was added to a final concentration of 1 mM when the final cultures reached a density of 20 Klett (660 nm) units. 

^dGA (2 mM) or PL (2 μM) was added to overnight starter, and final cultures were assayed for both PL and PN kinase activities. 

^ePL (2 μM) was added to overnight starter, and final cultures were assayed for both PL and PN kinase activities. 

^fGA (2 mM) was added to overnight starter, and final cultures were assayed for both PL and PN kinase activities. 

^gPL (100 μM) was added to overnight starter, and final cultures were assayed for PL kinase activity.