Methyltransferases acquired by lactococcal 936-type phage provide protection against restriction endonuclease activity

Table 1 Bacteria, phages, plasmids and primers used in this study

Bacteria	Features	Source
L. lactis NZ9000	Host strain for expression	[53]
L. lactis SM M	Host strain for Phi93	[23]
L. lactis SM E	Host strain for Phi145	[23]
L. lactis SM 13	Host strain for Phi15	[23]
L. lactis SM 11	2^nd propagating strain for Phi15	[23]
E. coli EC101_pPTPi	Strain carrying low-copy plasmid pPTPi	[23]
E. coli EC101	Host strain for cloning	[54]
E. coli K12	Competent, DAM^-/DCM^- Strain for pPiM.93DAM cloning	NEB
Phage	Features	Source
Phi15	Methylase positive^a	[23]
Phi93	Methylase positive	[23]
Phi145	Methylase positive	[23]
Plasmids	Features	Source
pPTPi	Tetracycline resistant, Nisin inducible, ^bTet^r	[52]
pPiM.93DAM	pPTPi derivative encoding mtPhi93-DAM, ^bTet^r	This study
pPiM.145I	pPTPi derivative encoding mtPhi145-1, ^bTet^r	This study
pPiM.145II	pPTPi derivative encoding mtPhi145-2, ^bTet^r	This study
Primers	Sequence (5'-3') ^c	Source
93DAMMTaseF	agcagcGGATCCAGGAGGCACTCACATGCACCATCATCATCATCATTCTTCTGGTAATAATGAATTAATG	This study
93DAMMTaseR	gctgctCCCGGGTTAATGATGATGATGATGGTGACCAGAAGTTCAAATATCACGACCATG	This study
Phi145.M1F	agcagcGGATCCaggaggcactcacATGCACCATCATCATCATCATTCTTCTGGTATTGAATTAAATAAA	This study
Phi145.M1R	agcagcCCCGGGTTACTATTCGTTTTCAGATAT	This study
Phi145.M2F	agcagcGGATCCaggaggcactcacATGCACCATCATCATCATCATTCTTCTGGTCTTAAGTTAGACGAG	This study
Phi145.M2R	agcagcCCCGGGTTAACTGTTTTTAACCATAAA
mcsPTPiFwd	CTGAGGTTCTTATGGCTC	[51]
mcsPTPiRev	TTCGCTTTTAAAGTCGATTTCAT	[51]

^aPredicted from BlastP and REBASE.
^bTet^r?=?Tetracycline resistant.
^cRestriction sites incorporated into oligonucleotide primer sequences are indicated in bold.

ISSN: 1471-2164