TABLE 1.

Bacterial strains used in this study

Sinorhizobium meliloti strain	Relevant characteristicsa	Source or reference(s)
Sm1021	Wild-type derivative of SU47; Strepr	45
chvID52E strain (EC220)	Succinoglycan gain-of-function allele in Sm1021 wild-type background, chvlD52E-chvI+; Strepr Hygr	25
chvIK214T strain (DW570)	Succinoglycan partial-loss-of-function allele, chvIK214T; Strepr Neor	46
exoS96 strain	Sm1021 exoS96::Tn5 Strepr Neor	26
exoY strain	Sm1021 exoY210::Tn5 Strepr Neor	47
exoA strain	Sm1021 exoA32::Tn233 Strepr Gentr	7
exoS96-exoA strain	exoS96 exoA double mutant; Strepr Gentr Neor	This study
chvID52E-exoY strain	chvlD52E exoY double mutant; Strepr Hygr	This study
exoV strain	Sm1021 exoV::Tn5 (exoV2) Strepr Neor	37
exoH strain	Sm1021 exoH::Tn5 Strepr Neor	34, 48
exoZ strain	Sm1021 exoZ::Tn5 Strepr Neor Rm8431	48

^aStrep^r, streptomycin resistant; Neo^r, neomycin resistant; Gent^r, gentamycin resistant; Hyg^r, hygromycin resistant.