Table I.

Assay for Higher Order Oligomers

Construct	JH607	XZ980
pZ150	100% ± 0%	100% ± 0%
pKH101	34 ± 7	116 ± 44
pJH157 (tetramer)	4 ± 2	78 ± 24
pJH370 (dimer)	45 ± 21	45 ± 16
D	80 ± 44	115 ± 48
E	7 ± 5	69 ± 4
F	38 ± 17	85 ± 5
G	34 ± 10	81 ± 24

Each construct used was assayed using β-galactosidase assays (See Methods). pZ150 is the empty vector. pKH101 is the N-terminal DNA binding domain of λcI repressor. Higher order oligomerization is needed to see stronger repression of lacZ in JH607 compared to XZ980.