Table 1 Strains and plasmids used in this study

E. coli DH5α

Host for plasmid cloning

Invitrogen

ATCC 13032

C. glutamicum wild type

Biotin auxotrophic

ATCC^a

CGR6

ATCC13032∆pta∆ackA∆ldh∆butA∆nagD, ∆ackA::P_tuf -alsSD

[9]

CGS1

CGR6 ∆ppc

This study

CGS2

CGR6 ∆pyc

This study

CGS3

CGR6 ∆ppc∆pyc

This study

CGS4

CGS3 ICD^A94D

This study

CGS5

CGS3 ICD^G407S

This study

CGS6

CGS3 ICD^R453S

This study

CGS7

CGR6 P₁-gltA

This study

CGS8

CGS1 P₁-gltA

This study

CGS9

CGS8 ∆butA::P_tuf -alsSD, ∆nagD::P_tuf -alsSD

This study

CGS11

CGS9 pEC-XK99E-alsSD-∆lacIq

This study

Plasmids

 pD-sacB

Kan^R; vector for in-frame deletion (sacB_B.sub.; lacZα; OriV_E.c.)

[56]

 pD-sacB-ppc

pD-sacB carrying the flanking sequences of the ppc gene

This study

 pD-sacB-pyc

pD-sacB carrying the flanking sequences of the pyc gene

This study

 pD-sacB-butA

pD-sacB carrying the flanking sequences of the butA gene

[41]

 pD-sacB-nagD

pD-sacB carrying the flanking sequences of the nagD gene

[9]

 pD-sacB-icd-mut-1

Kan^R, containing the nucleotide sequence for ICD amino acid exchange A94D

This study

 pD-sacB-icd-mut-2

Kan^R, containing the nucleotide sequence for ICD amino acid exchange G407S

This study

 pD-sacB-icd-mut-3

Kan^R, containing the nucleotide sequence for ICD amino acid exchange R453S

This study

 pD-sacB-P₁-gltA

Kan^R, containing P₁ promoter and gltA flanks

Unpublished work

 pD-sacB-butA-alsSD

Kan^R, containing P_tuf -alsSD flanks

This study

 pD-sacB-nagD-alsSD

Kan^R, containing P_tuf -alsSD flanks

This study

 pEC-XK99E

Kan^R; C. glutamicum/E. coli shuttle vector (P_trc, lacIq; pGA1, OriV_C.g., OriV_E.c.)

[57]

 pEC-XK99E-alsSD-ΔlacIq

Derived from pEC-XK99E, for the overexpression of alsS and alsD under promoter P_trc

[9]