Table 1 Strains and plasmids used in this study

S. flexneri

51579

Serotype 6, carrying 3/4-O-acetylation on Rha^III, used for oacC gene cloning and inactivation analysis, Ap^s, Km^s

[19]

G1671, G1038

Serotype 6, carrying 3/4-O-acetylation on Rha^III.

[18]

51579ΔoacC

Strain 51579 with the oacC gene replaced by the kanamycin resistance gene (kan) from pSR551, Km^r, Ap^s

this study

51579ΔoacC _pSQZ4

51579ΔoacC transformed by plasmid pSQZ4

this study

51579ΔoacC _pSQZ5

51579ΔoacC transformed by plasmid pSQZ5

this study

Sf301ΔoacB

Strain Sf301 with the oacB gene inactive, Km^r, Ap^s

[16]

Sf301ΔoacB_ pSQZ4

Sf301ΔoacB transformed by plasmid pSQZ4

[16]

Sf301ΔoacB_ pSQZ5

Sf301ΔoacB transformed by plasmid pSQZ5

this study

E. coli

DH5α

E. coli strain used for plasmid propagation and gene cloning

TaKaRa

Plasmid

pMD20T

T-A vector, Ap^r

TaKaRa

pSR551

Km^r, used for kan gene cloning

[24]

pKOBEG

A thermosensitive replicon that carries the λ phage redγβα operon expressed under the control of the arabinose-inducible pBAD promoter

[25]

pSQZ4

pMD20T carrying the whole sequence of the oacB gene from strain Sf301, Ap^r

[16]

pSQZ5

pMD20T carrying the whole sequence of the oacC gene from strain 51579, Ap^r

This study