Table 1. Bacterial strains and plasmid used in this work.

Strains		Genotype or description	Reference or source
C.crescentus	NA1000	Synchronizable derivative of CB15	20
	PC2179	CB15N dnaC303 temperature sensitive	33
E.coli	S17-1	294::RP4-2 (Tc::Mu) (Km::Tn7); conjugation strain	40
	DH10B	F– mcrA Δ(mrr-hsdRMS-mcrBC) φ80dlacZΔM15 ΔlacX74 endA1 recA1 deoR Δ(ara,leu)7697 araD139 galU galK nupG rpsL	Gibco BRL
	DH5α	F′ /endA1 hsdR17(rk–mk+) supE44 thi-1 recA1 gyrA (NaIr) relA1 Δ(lacIZYA-argF)U169 deoR [φ80dlacΔ(lacZ)M15]	Dr Michael S. DuBow
Plasmids	pBluescriptII	ApR; SK(+) or KS(+) cloning sites	Stratagene
	pGM1497	DH10B BluescriptII pSK(+) BamHI fragment C2 (includes dnaA)	This study
	pGM1499	DH10B BluescriptII pSK(+) BamHI fragment D	22
	pGM1500	DH10B BluescriptII pSK(+) BamHI fragment E (includes Cori)	22
	pGM1728	DH10B BluescriptII pSK(+) BamHI fragment C1	This study
	pGM1519	DH10B BluescriptII pKS(+) HindIII fragment B	This study
	pGM1542	DH10B BluescriptII pKS(+) EcoRI fragment A	This study
	PGM948	DH10B BluescriptII pSK(+) 810 bp XbaI to SalI C.crescentus dnaA	35
	pGM2526	DH5α BluescriptII pKS (+) 2.2 kb HincII/SacI fragment (containing Cori) of pGM1500	This study