TABLE 4.

Residues in the C-domain basic pocket of ZapC are important for interaction with FtsZ in a yeast two-hybrid assay

BD-fused proteina	AD-fused proteina	β-Galactosidase activityb	S.D.
–c	FtsZ	20.2	4.2
ZapC	–c	16.5	4
ZapC	FtsZ	100	6
ZapC L22P	FtsZ	17.9	1.1
ZapC K37A	FtsZ	78.8	11.7
ZapC M38A	FtsZ	116.1	19.1
ZapC K89A	FtsZ	75.1	15.7
ZapC K94A	FtsZ	65.4	6.1
ZapC R150A	FtsZ	77.8	7.7
ZapC K37D	FtsZ	36.1	12.6
ZapC K89D	FtsZ	25.4	9.8
ZapC K94D	FtsZ	23.9	1.2
ZapC R150E	FtsZ	43.5	5.1

^a WT ZapC and various ZapC mutants fused to the DNA binding domain (BD) were co-expressed with FtsZ fused to activation domain (AD) in yeast cells.

^b β-Galactosidase activity is provided in Miller units ± S.D. from at least three independent experiments. Miller units were calculated based on the formula (1000 × A₄₂₀)/(time × volume × A₆₆₀) where time and volume relate to reaction time and volumes. All interactions are reported relative to the full-length ZapC/FtsZ interaction, which is normalized to 100.

^c Dash indicates unfused binding or activation domains.