| single independent operator sites are involved in the genetic switch of the lactobacillus delbrueckii bacteriophage mv4. | the lysogeny region of the lactobacillus delbrueckii bacteriophage mv4 contains two divergently oriented orfs coding for the rep (221 aa) and tec (64 aa) proteins. the transcription of these two genes was analysed by primer extension and northern blot experiments on lysogenic strains. the location of the transcription initiation sites of rep and tec in the intergenic region allowed the identification of the divergently oriented non overlapping promoters p(rep) and p(tec). transcriptional fusions ... | 2007 | 17412387 |
| molecular taxonomy of lactobacillus phages. | forty-eight strains of lactobacilli used as starter strains in the dairy industry were examined for lysogeny after treatment with mitomycin c. two strains of l. delbrueckii subsp. bulgaricus were able to produce active phages. these temperate phages as well as 4 virulent phages isolated during abnormal fermentations were compared to a previously characterized phage mv4 which is temperate. all these phages were shown to be partially homologous by dna-dna hybridization. genes that code for viral p ... | 1988 | 3139062 |
| integrative recombination of lactobacillus delbrueckii bacteriophage mv4: functional analysis of the reaction and structure of the attp site. | the integrase of the temperate bacteriophage mv4 catalyzes site-specific recombination between the phage attp site and the attb site of the host during lysogenization of lactobaccillus delbrueckii subsp. bulgaricus. the mv4 integrase also functions in a wide variety of gram-positive bacteria and in escherichia coli. in this report, in vitro and in vivo recombination assays were developed and the integrase was purified in order to study in greater detail the mv4 attp x attb recombination event. i ... | 1999 | 10517333 |
| plasmid integration in a wide range of bacteria mediated by the integrase of lactobacillus delbrueckii bacteriophage mv4. | bacteriophage mv4 is a temperate phage infecting lactobacillus delbrueckii subsp. bulgaricus. during lysogenization, the phage integrates its genome into the host chromosome at the 3' end of a trna(ser) gene through a site-specific recombination process (l. dupont et al., j. bacteriol., 177:586-595, 1995). a nonreplicative vector (pmc1) based on the mv4 integrative elements (attp site and integrase-coding int gene) is able to integrate into the chromosome of a wide range of bacterial hosts, incl ... | 1997 | 9068626 |
| molecular comparison of the structural proteins encoding gene clusters of two related lactobacillus delbrueckii bacteriophages. | virulent phage ll-h and temperate phage mv4 are two related bacteriophages of lactobacillus delbrueckii. the gene clusters encoding structural proteins of these two phages have been sequenced and further analyzed. six open reading frames (orf-1 to orf-6) were detected. protein sequencing and western immunoblotting experiments confirmed that orf-3 (g34) encoded the main capsid protein gp34. the presence of a putative late promoter in front of the phage ll-h g34 gene was suggested by primer extens ... | 1993 | 8497043 |
| primary structure and functional analysis of the lysis genes of lactobacillus gasseri bacteriophage phi adh. | the lysis genes of the lactobacillus gasseri bacteriophage phi adh were isolated by complementation of a lambda sam mutation in escherichia coli. nucleotide sequencing of a 1,735-bp dna fragment revealed two adjacent coding regions of 342 bp (hol) and 951 bp (lys) in the same reading frame which appear to belong to a common transcriptional unit. proteins corresponding to the predicted gene products, holin (12.9 kda) and lysin (34.7 kda), were identified by in vitro and in vivo expression of the ... | 1995 | 7836307 |
| control of directionality in bacteriophage mv4 site-specific recombination: functional analysis of the xis factor. | the integrase of the temperate bacteriophage mv4 catalyzes site-specific recombination between the phage attp site and the host attb site during lactobacillus delbrueckii lysogenization. the mv4 prophage is excised during the induction of lytic growth. excisive site-specific recombination between the attr and attl sites is also catalyzed by the phage-encoded recombinase, but the directionality of the recombination is determined by a second phage-encoded protein, the recombination directionality ... | 2010 | 19948798 |
| characterization of genetic elements required for site-specific integration of lactobacillus delbrueckii subsp. bulgaricus bacteriophage mv4 and construction of an integration-proficient vector for lactobacillus plantarum. | temperate phage mv4 integrates its dna into the chromosome of lactobacillus delbrueckii subsp. bulgaricus strains via site-specific recombination. nucleotide sequencing of a 2.2-kb attp-containing phage fragment revealed the presence of four open reading frames. the larger open reading frame, close to the attp site, encoded a 427-amino-acid polypeptide with similarity in its c-terminal domain to site-specific recombinases of the integrase family. comparison of the sequences of attp, bacterial at ... | 1995 | 7836291 |
| defective site-specific integration elements are present in the genome of virulent bacteriophage ll-h of lactobacillus delbrueckii. | the phage attachment site, attp, and the integrase-encoding gene, int, are sufficient to promote site-specific integration of the temperate phage mv4 genome into the chromosome of the lactobacillus delbrueckii host (l. dupont, b. boizet-bonhoure, m. coddeville, f. auvray, and p. ritzenthaler, j. bacteriol. 177:586--595, 1995). the mv4 genome region containing these elements was compared at the nucleotide and amino acid levels with that of the closely related virulent phage ll-h. complex dna rear ... | 1996 | 8633887 |
| unusual structure of the attb site of the site-specific recombination system of lactobacillus delbrueckii bacteriophage mv4. | the temperate phage mv4 integrates its genome into the chromosome of lactobacillus delbrueckii subsp. bulgaricus by site-specific recombination within the 3' end of a trna(ser) gene. recombination is catalyzed by the phage-encoded integrase and occurs between the phage attp site and the bacterial attb site. in this study, we show that the mv4 integrase functions in vivo in escherichia coli and we characterize the bacterial attb site with a site-specific recombination test involving compatible pl ... | 1999 | 10572145 |
| genome homology and superinfection immunity between temperate and virulent lactobacillus delbrueckii bacteriophages. | the presence of short homologous dna segments along the genomes of the temperate phage mv4 and the virulent phages ll-h, ll-k and jcl1032 of lactobacillus delbrueckii was demonstrated with southern hybridizations. one of these segments, the 2,817 nt mis element of phage mv4, was further characterized by nucleotide sequence analysis and by superinfection immunity studies. | 1995 | 8572946 |