title: AbiV, a novel antiphage abortive infection mechanism on the chromosome of Lactococcus lactis subsp. cremoris MG1363.
abstract: Insertional mutagenesis with pGhost9::ISS1 resulted in independent insertions in a 350-bp region of the chromosome of Lactococcus lactis subsp. cremoris MG1363 that conferred phage resistance to the integrants. The orientation and location of the insertions suggested that the phage resistance phenotype was caused by a chromosomal gene turned on by a promoter from the inserted construct. Reverse transcription-PCR analysis confirmed that there were higher levels of transcription of a downstream open reading frame (ORF) in the phage-resistant integrants than in the phage-sensitive strain L. lactis MG1363. This gene was also found to confer phage resistance to L. lactis MG1363 when it was cloned into an expression vector. A subsequent frameshift mutation in the ORF completely eliminated the phage resistance phenotype, confirming that the ORF was necessary for phage resistance. This ORF provided resistance against virulent lactococcal phages belonging to the 936 and c2 species with an efficiency of plaquing of 10(-4), but it did not protect against members of the P335 species. A high level of expression of the ORF did not affect the cellular growth rate. Assays for phage adsorption, DNA ejection, restriction/modification activity, plaque size, phage DNA replication, and cell survival showed that the ORF encoded an abortive infection (Abi) mechanism. Sequence analysis revealed a deduced protein consisting of 201 amino acids which, in its native state, probably forms a dimer in the cytosol. Similarity searches revealed no homology to other phage resistance mechanisms, and thus, this novel Abi mechanism was designated AbiV. The mode of action of AbiV is unknown, but the activity of AbiV prevented cleavage of the replicated phage DNA of 936-like phages.
authors.affiliation: Center for Systems Microbiology, DTU Biosys, Technical University of Denmark, Lyngby, Denmark.
authors.forename: Jakob
authors.initials: J
authors.lastname: Haaber
authors.forename: Sylvain
authors.initials: S
authors.lastname: Moineau
authors.forename: Louis-Charles
authors.initials: LC
authors.lastname: Fortier
authors.forename: Karin
authors.initials: K
authors.lastname: Hammer
mesh_terms: D001426:Bacterial Proteins / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D001435:Bacteriophages / Q000254:growth & development* / Q000276:immunology*; D003001:Cloning, Molecular; D004251:DNA Transposable Elements; D019281:Dimerization; D016368:Frameshift Mutation; D018628:Gene Dosage; D020869:Gene Expression Profiling; D023061:Gene Order; D013294:Lactococcus lactis / Q000502:physiology* / Q000821:virology*; D016254:Mutagenesis, Insertional; D016366:Open Reading Frames; D012329:RNA, Bacterial / Q000096:biosynthesis; D012333:RNA, Messenger / Q000096:biosynthesis; D017422:Sequence Analysis, DNA; D017906:Siphoviridae / Q000254:growth & development / Q000276:immunology; D010948:Viral Plaque Assay
chemical_list: D001426:Bacterial Proteins; D004251:DNA Transposable Elements; D012329:RNA, Bacterial; D012333:RNA, Messenger
references.citation: Antonie Van Leeuwenhoek. 1999 Jul-Nov;76(1-4):89-113
references.pmid: 10532374
references.citation: J Bacteriol. 1995 Jul;177(13):3818-23
references.pmid: 7601848
references.citation: Appl Environ Microbiol. 1993 Jan;59(1):208-12
references.pmid: 16348844
references.citation: Mol Microbiol. 2000 Feb;35(3):517-28
references.pmid: 10672175
references.citation: Appl Environ Microbiol. 1991 Jan;57(1):283-8
references.pmid: 16348396
references.citation: Virology. 1978 Mar;85(1):118-28
references.pmid: 347693
references.citation: Microbiology (Reading). 2002 Apr;148(Pt 4):985-1001
references.pmid: 11932445
references.citation: Gene. 1998 May 28;212(1):5-11
references.pmid: 9661658
references.citation: Syst Appl Microbiol. 1983;4(3):413-23
references.pmid: 23194740
references.citation: Genome Res. 2001 May;11(5):731-53
references.pmid: 11337471
references.citation: Antonie Van Leeuwenhoek. 1999 Jul-Nov;76(1-4):377-82
references.pmid: 10532393
references.citation: Appl Environ Microbiol. 1996 Sep;62(9):3075-82
references.pmid: 8795193
references.citation: Appl Environ Microbiol. 1994 Jun;60(6):1832-41
references.pmid: 16349277
references.citation: J Biotechnol. 1999 Jan 22;67(2-3):135-49
references.pmid: 9990732
references.citation: Virology. 2002 May 10;296(2):308-20
references.pmid: 12069529
references.citation: Virology. 2000 Sep 30;275(2):267-77
references.pmid: 10998327
references.citation: J Bacteriol. 1992 Sep;174(17):5633-8
references.pmid: 1324906
references.citation: Appl Environ Microbiol. 1980 Sep;40(3):500-6
references.pmid: 16345629
references.citation: J Bacteriol. 1983 Apr;154(1):1-9
references.pmid: 6403500
references.citation: Virology. 2008 Apr 10;373(2):298-309
references.pmid: 18191977
references.citation: Appl Environ Microbiol. 1987 Oct;53(10):2452-7
references.pmid: 2447829
references.citation: Appl Environ Microbiol. 1991 May;57(5):1346-53
references.pmid: 16348479
references.citation: J Bacteriol. 1995 Jul;177(13):3824-9
references.pmid: 7601849
references.citation: FEMS Microbiol Lett. 2006 Aug;261(2):253-61
references.pmid: 16907729
references.citation: J Bacteriol. 1994 Nov;176(21):6457-63
references.pmid: 7961396
references.citation: J Dairy Sci. 1998 Jun;81(6):1483-5
references.pmid: 9684156
references.citation: Appl Environ Microbiol. 1995 Jun;61(6):2193-202
references.pmid: 7793939
references.citation: Appl Environ Microbiol. 2004 Oct;70(10):5825-32
references.pmid: 15466520
references.citation: Mol Microbiol. 1997 Oct;26(1):49-64
references.pmid: 9383189
references.citation: J Bacteriol. 1996 Feb;178(3):931-5
references.pmid: 8550537
references.citation: Appl Environ Microbiol. 1989 Dec;55(12):3119-23
references.pmid: 16348073
references.citation: J Bacteriol. 1998 Jun;180(12):3174-80
references.pmid: 9620968
references.citation: Proc Natl Acad Sci U S A. 1987 Jun;84(12):4171-5
references.pmid: 2438693
references.citation: Appl Environ Microbiol. 1995 Dec;61(12):4321-8
references.pmid: 8534099
references.citation: Appl Environ Microbiol. 1999 Nov;65(11):4793-8
references.pmid: 10543788
references.citation: FEMS Microbiol Lett. 1996 Sep 1;142(2-3):295-9
references.pmid: 8810513
references.citation: J Bacteriol. 2007 Feb;189(4):1482-7
references.pmid: 17041060
references.citation: Appl Environ Microbiol. 1990 Jan;56(1):202-9
references.pmid: 16348092
references.citation: Appl Environ Microbiol. 1997 Apr;63(4):1274-83
references.pmid: 9097424
references.citation: Appl Environ Microbiol. 1996 Feb;62(2):676-9
references.pmid: 16535245
references.citation: Microbiology (Reading). 2000 Feb;146 ( Pt 2):445-453
references.pmid: 10708383
references.citation: Appl Microbiol. 1975 Jun;29(6):807-13
references.pmid: 16350018
references.citation: Appl Environ Microbiol. 1991 Dec;57(12):3547-51
references.pmid: 1664711
references.citation: Appl Environ Microbiol. 1993 Dec;59(12):4363-6
references.pmid: 16349136
references.citation: Appl Environ Microbiol. 2000 Sep;66(9):3790-7
references.pmid: 10966392
references.citation: Appl Environ Microbiol. 2001 Nov;67(11):5225-32
references.pmid: 11679349
references.citation: J Bacteriol. 2004 Feb;186(3):713-21
references.pmid: 14729697
references.citation: J Dairy Sci. 2000 Jul;83(7):1448-50
references.pmid: 10908051
references.citation: FEMS Microbiol Lett. 1998 Feb 15;159(2):331-6
references.pmid: 9503629
references.citation: Nucleic Acids Res. 1997 Sep 1;25(17):3389-402
references.pmid: 9254694
references.citation: Appl Environ Microbiol. 1999 Jan;65(1):330-5
references.pmid: 9872803
references.citation: FEMS Microbiol Lett. 2002 Sep 10;214(2):283-7
references.pmid: 12351244
references.citation: J Bacteriol. 1997 May;179(9):2949-57
references.pmid: 9139913
references.citation: J Bacteriol. 2002 Nov;184(22):6325-32
references.pmid: 12399502
references.citation: J Bacteriol. 2007 Feb;189(4):1417-25
references.pmid: 17012400
references.citation: Appl Environ Microbiol. 1994 Apr;60(4):1129-36
references.pmid: 16349225
references.citation: Curr Opin Microbiol. 2005 Aug;8(4):473-9
references.pmid: 15979388
references.citation: Microbiology (Reading). 1994 Nov;140 ( Pt 11):3061-9
references.pmid: 7812447
references.citation: Appl Environ Microbiol. 1990 Jul;56(7):2255-8
references.pmid: 2389939
references.citation: J Bacteriol. 2007 Apr;189(8):3256-70
references.pmid: 17307855
references.citation: Appl Environ Microbiol. 1995 May;61(5):2023-6
references.pmid: 7646042
references.citation: Mol Gen Genet. 1996 Nov 27;253(1-2):217-24
references.pmid: 9003306
references.citation: Appl Environ Microbiol. 1998 Dec;64(12):4748-56
references.pmid: 9835558
references.citation: J Bacteriol. 1986 Sep;167(3):905-19
references.pmid: 3017919
references.citation: Antonie Van Leeuwenhoek. 2002 Aug;82(1-4):303-21
references.pmid: 12369198
references.citation: J Bacteriol. 2001 May;183(9):2785-94
references.pmid: 11292797