Table 1.

Strains and plasmids used

Strain or plasmidRelevant characteristicsReference and/or source
E. coli
 JM83F ara Δ(lac-proAB) rpsL (Strr) [φ80dlacΔ(lacZ)M15]thi 52
 XL1-Blue MRF′Δ(mcrA)183Δ(mcrCB-hsdSMR-mrr)173 endA1 supE44 thi-1 recA1 gyrA96 relA1 lac[F′ proAB lacI q ZΔM15 Tn10(Tetr)]Stratagene
 XLOLRΔ(mcrA)183Δ(mcrCB-hsdSMR-mrr)173 endA1 thi-1 recA1 gyrA96 relA1 lac[F′ proAB lacI q ZΔM15Tn10 (Tetr)] Suλr Stratagene
S. mutans
 LT11 45
 LT11regM regM::Tet Tetr This study
 LT11 pepQ pepQ::pVA8912 Ermr This study
 GS-5Laboratory strain
 GS-5 regM regM::pVA8912 Ermr This study
 GS-5pepQ pepQ::pVA8912 Ermr This study
 Pro-1GS-5 Tn916, Tetr, proline auxotroph of GS-5 28
 Pro-1 regM regM::pVA8912 Tetr Ermr This study
pepQ::pVA8912 TetrErmr This study
Vectors
 Lambda Zap ExpressKanr Stratagene
 pGEM-TApr, 3′ T overhangsPromega
 pUC19Apr 52
 pVA8912pVA8911 without 412-bp PvuII fragment, Ermr H. Malke (23)
 pLN2Apr Tetr 27
Plasmids
 pOB208 pepQ regM amy(N-terminus) Kanr This study
 pOB209 regM amy Kanr This study
 pOB210 regM(C-terminus) amy Kanr This study
 pOB215 pepQ regM amy (N-terminus) Kanr This study