Table 1 Bacterial strains and plasmids used in this work

Bacterial strains

E. coli TG1

supE, hsd, Δ5, thi, Δ (lac-proAB), F'(traD36 proAB-lacZΔM15)

[50]

L. lactis NZ9000

L. lactis subsp. cremoris (derivative strain of MG1363, carrying nisRK genes on the chromosome)

[51]

Plasmids

pMal-GroEL

pMal expression vector carrying the B. abortus groEL gene

[17]

pCYT:Nuc

pWV01/Cm^r; expression vector containing the fusion rbs_{Usp 45}::nucB, under the control of P _nisA

[34]

pSEC:Nuc

pWV01/Cm^r; expression vector containing the fusion rbs_{Usp 45}::sp_{Usp 45}::nucB, under the control of P _nisA

[34]

pSEC:LEISS:Nuc

pWV01/Cm^r; expression vector containing the fusion rbs_{Usp 45}::sp_{Usp 45}::LEISS::nucB, under the control of P _nisA

[33]

pCYT:groEL

pWV01/Cm^r; plasmid containing the fusion rbs_{Usp 45}::groEL, under the control of P _nisA

This work

pSEC:groEL

pWV01/Cm^r; plasmid containing the fusion rbs_{Usp 45}::sp_{Usp 45}::groEL, under the control of P _nisA

This work

pSEC:LEISS:groEL

pWV01/Cm^r; plasmid containing the fusion rbs_{Usp 45}::sp_{Usp 45}::LEISS::groEL, under the control of P _nisA

This work