Table 3 Strains and plasmids used in this study

Strains

 L. plantarum

  NC8

Host strain, plasmid-free, silage isolate

[55]

  NC8/Δalr

d-Alanine auxotroph

This work

 E. coli

  χ6212

asd auxotroph, cloning host

[51]

  TOP10

Cloning host

Takara (Dalian, China)

Plasmids

 pNZ5319

Cm^r,erm^r, containing lox66-P32-cat-lox71 fragment

[53]

 pNZ5348

erm^r,Cre-recombinase expression

[53]

 pLp_1261Inv

erm^r; pLp_2588sAmyA derivative where the Lp_2588-AmyA cassette has been replaced by the lp_1261 and Inv fusion gene fragment

[54]

 pLp-S

erm^r, pLp_1261Inv derivative, where lp_1261 and Inv fusion gene has been replaced by the SP-linker-S_anchoring sequence of SlpA gene containing MCS1

This work

 pLp-pgsA′

erm^r, pLp_1261Inv derivative, where lp_1261 inv gene has been replaced by pgsA′ gene containing MCS2.

This work

 pLP-pgsA′-EGFP

erm^r, pLP-pgsA′, derivative, EGFP was cloned in XbaI/Hind III sites, containing a truncated pgsA gene, pgsA′ (567 bp)

This work

 pLp-EGFP-S

erm^r, pLp-S derivative, EGFP was cloned into SalI/XhoI sites

This work

 pYA3342

Containing asd fragment

[57]

 pLQa-pgsA′

pLP-pgsA′ derivative, the erm was replaced by the asd-alr

This work

 pLQa-pgsA′-EGFP

pLp-pgsA′-EGFP derivative, the erm was replaced by the asd-alr

This work

 pLQa-S

pLp-S derivative, the erm was replaced by the asd-alr

This work

 pLQa-EGFP-S

pLp-EGFP-S derivative, the erm was replaced by the asd-alr

This work

 pLQa-p′mCherry

pLQa-pgsA′ derivative, mCherry inserted into XbaI/HindIII-digested sites

This work

 pLQa-p′m-ES

pLQa-p′mCherry derivative, SP-linker-EGFP-S_anchoring fusion gene inserted into HindIII-digested sites with introduction of the SD sequence

This work

 pLQa-ES-p′m

pLQa-EGFP-S derivative, pgsA′-mCherry-His tag fusion gene inserted into HindIII sites with introduction of the SD sequence

This work

 pLQa-AMA1S-p′EtMIC2

pLQa-ES-P′m derivative, AMA1 gene inserted into SalI/XhoI sites, EtMIC2 gene inserted into XbaI/HindIII-digested sites

This work