Table 1 E. faecium strains and plasmids used in this work

Strains

E. faecium

TX16 (DO)

Sequenced endocarditis clinical isolate, Em^r, Sm^r. ST-16^a http://www.hgsc.bcm.tmc.edu

TX1330RF

Fs^r and Rf^r derivative of TX1330, a faecal colonizing strain from a healthy human volunteer

TX1330RF (pHyl_EfmTX16)

Derivative of TX1330RF to which the hyl _Efm -containing plasmid (pHyl_EfmTX16) was transferred by conjugation from TX16 (DO) (~250 kb)

TX1330RF (pHyl_{EfmTX16Δ7,534})

Mutant with deletion of part or all of 6 genes of the hyl _Efm region of TX1330RF(pHyl_EfmTX16)

TX1330RF (pHyl_{EfmTX16Δ4genes})

Non-polar deletion of 4 genes of the hyl _Efm region of TX1330RF(pHyl_EfmTX16)

TX1330RF (pHyl_{EfmTX16Δ hyl} )

Non-polar deletion mutant of hyl _Efm of TX1330RF(pHyl_EfmTX16)

TX1330RF (pHyl_{EfmTX16Δ hyl-down} )

Non-polar deletion of hyl _Efm plus its downstream gene of TX1330RF(pHyl_EfmTX16)

TX1330RF (pHyl_{EfmTX16Δ down} )

Non-polar deletion of the gene downstream of hyl _Efm of TX1330RF(pHyl_EfmTX16)

E. faecalis

CK111

OG1Sp upp4::P₂₃ repA4

Plasmids

pHyl_EfmTX16

Conjugative and transferable megaplasmid (ca. 250 kb) of TX16 (DO) containing hyl _Efm

pCJK47

Conjugative donor plasmid for markerless mutagenesis; oriT_pCF10 and pheS* pORI280 derivative; confers Em^r

pHOU1

Derivative of pCJK47 in which the erm(C) gene was replaced by aph-2'-ID; confers Gm^r

pHOU2

Derivative of pCJK47 in which the erm(C) gene was replaced by aph-2'-ID and cat was incorporated in the cloning site for allelic replacements; confers Gm^r.

pTEX5501ts

E. coli-enterococcal shuttle plasmid for mutagenesis using a temperature-sensitive replicon

pAT392

oriR_pAMβ1, oriR_pUC oriT_RK2 spc lacZα P2 aac(6')-aph(2")

pAT392::hyl _Efm

Derivative of pAT392 containing hyl _Efm (cloned with SacI and SmaI) under the control of the P2 promoter

pAT392::hyl _Efm- down

Derivative of pAT392 containing both the hyl _Efm plus downstream genes (cloned with SacI and SmaI) under the control of the P2 promoter