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Twenty Years of Collaboration to Sort out Phage Mu Replication and Its Dependence on the Mu Central Gyrase Binding Site. Viruses 2023; 15:v15030637. [PMID: 36992345 PMCID: PMC10052514 DOI: 10.3390/v15030637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 02/23/2023] [Accepted: 02/24/2023] [Indexed: 03/02/2023] Open
Abstract
For 20 years, the intricacies in bacteriophage Mu replication and its regulation were elucidated in collaboration between Ariane Toussaint and her co-workers in the Laboratory of Genetics at the Université Libre de Bruxelles, and the groups of Martin Pato and N. Patrick Higgins in the US. Here, to honor Martin Pato’s scientific passion and rigor, we tell the history of this long-term sharing of results, ideas and experiments between the three groups, and Martin’s final discovery of a very unexpected step in the initiation of Mu replication, the joining of Mu DNA ends separated by 38 kB with the assistance of the host DNA gyrase.
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Abstract
Phage Mu is the paradigm of a growing family of bacteriophages that infect a wide range of bacterial species and replicate their genome by replicative transposition. This molecular process, which is used by other mobile genetic elements to move within genomes, involves the profound rearrangement of the host genome [chromosome(s) and plasmid(s)] and can be exploited for the genetic analysis of the host bacteria and the in vivo cloning of host genes. In this chapter we review Mu-derived constructs that optimize the phage as a series of genetic tools that could inspire the development of similarly efficient tools from other transposable phages for a large spectrum of bacteria.
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Affiliation(s)
- Ariane Toussaint
- Université Libre de Bruxelles; Génétique et physiologie bactérienne (LGPB) ; Campus de Gosselies - CP300 ; Charleroi (Gosselies), Belgium
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Forbes KJ, Pérombelon MC. Chromosomal mapping in Erwinia carotovora subsp. carotovora with the IncP plasmid R68::Mu. J Bacteriol 1985; 164:1110-6. [PMID: 2933392 PMCID: PMC219304 DOI: 10.1128/jb.164.3.1110-1116.1985] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Conjugational gene transfer was established in Erwinia carotovora subsp. carotovora SCRI193 by using plasmid R68::Mu c+ to mobilize the chromosome into multiply mutant recipients. It was observed that although the plasmid alone mobilized markers randomly at a frequency of ca. 10(-5) chromosomal recombinants per donor, the presence of a Mu prophage on the chromosome of the donor increased the frequency of mobilization of markers adjacent to the prophage by up to 10-fold. Using this system it was possible to order 17 chromosomal mutations. The behavior of Mu in E. carotovora subsp. carotovora was also studied.
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Piruzian ES, Koretskaya NG. A genetic study of Escherichia coli strains carrying Mu-lambda-Mu structures. MOLECULAR & GENERAL GENETICS : MGG 1983; 190:133-8. [PMID: 6222245 DOI: 10.1007/bf00330335] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
We have studied the interaction of bacteriophages Mu and lambda after their simultaneous induction and the influence of lambda on Mu-dependent mobilization of the E. coli chromosome by the RP4 plasmid. Heterolysogenic E. coli strains carrying Mu-lambda-Mu structures were constructed (Faelen et al. 1975). The Mu and lambda prophages are linked in such structures, and the functions of some lambda genes are disturbed depending on the integration site. A study of the inhibition of Mu growth by lambda after their simultaneous induction was performed and the region of the lambda genome (R-H) which contains the gene(s) responsible for the inhibitory effect of lambda on Mu was identified. The efficiency of Mu-dependent mobilization of the bacterial chromosome by RP4 is shown to be an order of magnitude lower in strains with unlinked Mu and lambda and an order of magnitude higher in strains with some permutations of the lambda prophage than in the control Mu-monolysogenic E. coli strain. Thus the effect of Mu on mobilization depends on the localization of the lambda prophage and on the functioning of its genome within a Mu-lambda-Mu structure. It is presumed that the mobilization of the bacterial chromosome is stimulated by effective replication of the Mu genome starting from the ori site (origin of replication) of the lambda prophage within the Mu-lambda-Mu structure. We propose a model to explain the interaction of Mu and lambda in E. coli strains carrying Mu-lambda-Mu structures.
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Phage Mu: Transposition as a Life-Style. Mob Genet Elements 1983. [DOI: 10.1016/b978-0-12-638680-6.50007-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] Open
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Chaconas G, Harshey RM, Sarvetnick N, Bukhari AI. Predominant end-products of prophage Mu DNA transposition during the lytic cycle are replicon fusions. J Mol Biol 1981; 150:341-59. [PMID: 6271975 DOI: 10.1016/0022-2836(81)90551-9] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Abstract
Several derivatives of phages Mu and D108 have been isolated that carry an internal deletion generated by one of the IS1 components of a Tn9 transposon located in the A, B, or S gene of the prenatal phage. The deletions remove most of the lytic functions of the phage but leave intact either genes A and B or gene A and the left and the right end of the phages. These deleted derivatives, called mini-Mu and mini-D108, were physically characterized by electron microscopy and digestion with restriction enzymes. Mini-Mu and mini-D108, which carry an antibiotic resistance marker, are described and some of their genetic properties are summarized in the paper by Toussaint et al. (1981).
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Toussaint A, Faelen M, Résibois A. Chromosomal rearrangements induced by mini-Mu and mini-D108: mini review and new data. Gene 1981; 14:115-9. [PMID: 6455331 DOI: 10.1016/0378-1119(81)90153-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Toussaint A, Desmet L, van Gijsegem F, Faelen M. Genetic analysis of mu or mini-mu containing F' pro lac episomes after prophage induction. MOLECULAR & GENERAL GENETICS : MGG 1981; 181:201-6. [PMID: 6456399 DOI: 10.1007/bf00268427] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
We have investigated the fate of different F pro lac episomes carrying a Mu or mini-Mu, after induction of the Mu or mini-Mu prophage, by looking at the frequencies of transfer of the episome and of one chromosomal marker. During the first 10 min after induction the frequency of chromosome mobilization increases while the frequency of episome transfer decreases. This suggests that the F interacts with the chromosome through some kind of Mu mediated process. Later the transfer of both the episome and chromosomal markers is inhibited. Possible reasons for this inhibition are discussed.
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Bialy H, Waggoner BT, Pato ML. Fate of plasmids containing Mu DNA: chromosome association and mobilization. MOLECULAR & GENERAL GENETICS : MGG 1980; 180:377-83. [PMID: 6450874 DOI: 10.1007/bf00425851] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The fluorescent dye, diamidinophenylindole-dihydrochloride (DAPI) can be added to CsCl gradients to enhance the density resolution of DNA species, independent of their topological configurations. When Proteus mirabilis and Escherichia coli strains carrying an RP4::Mucts plasmid were examined with the use of such a technique, it was found that after thermal induction of the prophage essentially al of the plasmid DNA became associated with the chromosome. This quantitative association is detergent-RNase- and pronase-resistant and dependent on the expression of Mu genes. The association is temporally, and probably functionally, correlated with the onset of Mu DNA replication. Genetic studies with F'::mini Mu plasmids indicate that some of the association results in stable Hfr formation, and does not require the product of Mu gene B.
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Faelen M, Toussaint A. Inversion induced by temperature bacteriophage mu-1 in the chromosome of Escherichia coli K-12. J Bacteriol 1980; 142:391-9. [PMID: 6445891 PMCID: PMC293983 DOI: 10.1128/jb.142.2.391-399.1980] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Induction of the Mu prophage of a lysogenic HfrP4X strongly stimulates the early transfer of the purE gene, which is located far from the origin of transfer. By using a rec- Mu cts62 X lysogenic donor, it was established that this process reflects the inversion of the origin of transfer in part of the Hfr population. Hfr's with inverted polarity of gene transfer were isolated; their analysis suggests that two Mu genomes in opposite orientation surround the inverted DNA fragment. Due to the presence of the Mu genome of the invertible G segment, homologous regions in the same orientation can appear in Mu genomes in opposite orientation. In a Rec+ background, Hfr's with inverted polarity (i) return to their original polarity of transfer by recomination between the two inverted Mu and (ii) produce new F' strains by recombination between the two similarly oriented G segments.
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Schumann W, Bade EG. In vitro constructed plasmids containing both ends of bacteriophage Mu DNA express phage functions. MOLECULAR & GENERAL GENETICS : MGG 1979; 169:97-105. [PMID: 286147 DOI: 10.1007/bf00267550] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The construction of a plasmid carrying the right end PstI . B fragment of bacteriophage Mu DNA and of plasmids containing in addition the left end EcoRI.C fragment of Mu DNA into the vector pBR322 is described. Inversion of the G segment still occurs in all these plasmids. By marker rescue and complementation experiments the right PstI cleavage site was located to the left of gene Q. The composite plasmids inheriting also the left end EcoRI fragment of Mu DNA express both the immunity and killing functions of Mu and direct the in vitro synthesis of presumably Mu-specific polypeptides. These results demonstrates that Mu-specific functions can be analyzed from cloned fragments.
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Abstract
Nucleotide sequences were analyzed across the two ends of lysogenic Mu DNA. These ends were cloned separately in lambdapMu hybrid particles that derived from a single Mu lysogen in the lac Z part of lambdaplac5. The obtained data imply that Mu lysogenization was associated with the duplication of 5 base pairs present in lac DNA at the Mu insertion site. As a result of this duplication, Mu DNA is flanked by two copies of five identical base pairs oriented as direct repeats. A similar conclusion has been obtained independently by other investigators with the use of a different Mu lysogen (D. Kamp and R. Kahmann, personal communication). Thus Mu insertion seems to have a striking similarity to typical IS-mediated insertions that were found to be associated with a short DNA duplication at the target site.
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Faelen M, Toussaint A. Stimulation of deletions in the Escherichia coli chromosome by partially induced Mucts62 prophages. J Bacteriol 1978; 136:477-83. [PMID: 361710 PMCID: PMC218569 DOI: 10.1128/jb.136.2.477-483.1978] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Deletion of bacterial DNA fragments is stimulated in induced Mucts62 lysogens. The host genes located proximally to the prophage are more frequently lost than those which are unlinked to the Mu genome. Genes located on either side of a Mu genome are deleted in the same manner. Like the other Mu-induced rearrangements, this process is recA independent and requires the participation of Mu DNA, as indicated by the fact that a phage genome always replaces the deleted genes. Data are presented which strongly suggest that both ends of the Mu genome are involved in deletion formation.
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Giphart-Gassler M, van de Putte P. Early gene products of bacteriophage Mu. Identification of the B gene product. J Mol Biol 1978; 120:1-12. [PMID: 347088 DOI: 10.1016/0022-2836(78)90292-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Faelen M, Huisman O, Toussaint A. Involvement of phage Mu-1 early functions in Mu-mediated chromosomal rearrangements. Nature 1978; 271:580-2. [PMID: 340966 DOI: 10.1038/271580a0] [Citation(s) in RCA: 69] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Wijffelman C, Lotterman B. Kinetics of Mu DNA synthesis. MOLECULAR & GENERAL GENETICS : MGG 1977; 151:169-74. [PMID: 876022 DOI: 10.1007/bf00338691] [Citation(s) in RCA: 64] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Mu specific DNA synthesis starts at 10 min after infection. All essentail amber mutants of Mu were tested for the ability to replicate in a non permissive host. Except for the amber mutants A and B, which were already known to be blocked in Mu DNA synthesis (Wijffelman et al., 1974), all the other mutants showed normal Mu DNA replication. Using mitomycin C-treated cells Mu DNA synthesis was found to start at about 20 min after induction. However using the much more sensitive method of DNA-RNA hybridization, it was found that the DNA synthesis starts already at 10 min after induction, and that at 20 min after induction about 7 copies of the Mu DNA are present per cell.
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Faelen M, Toussaint A. Bacteriophage Mu-1: a tool to transpose and to localize bacterial genes. J Mol Biol 1976; 104:525-39. [PMID: 781292 DOI: 10.1016/0022-2836(76)90118-2] [Citation(s) in RCA: 73] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Westmaas GC, van der Maas WL, van de Putte P. Defective prophages of bacteriophage Mu. MOLECULAR & GENERAL GENETICS : MGG 1976; 145:81-7. [PMID: 775313 DOI: 10.1007/bf00331561] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
A method is described for the isolation of thermoinducible defective Mu lysogens. Four of these defective lysogens were studied more extensively. By marker-rescue experiments it was shown that the strain harbouring the smallest defective prophage contains the immunity gene cts and the genes A and B; the strain with the largest defective prophage still contains all the known essential genes of Mu, A to S (see Fig. 1). After induction at 43 degrees C all the defective lysogens are killed, whereas no lysis occurs. Although in all the thermoinducible defective lysogens the A and B gene products could be demonstrated by complementation, these gene products are not responsible for the killing of the host, suggesting the presence of another unknown early gene product of Mu. The level of complementation of a mutation in gene A is reduced by the presence in the cell of another defective Mu prophage containing the "G" beta part of Mu. This effect on A gene complementation is markedly enhanced when the defective prophage, containing the "G" beta part, is located on an episome instead of on the chromosome. Complementation of late genes by a defective prophage located on the chromosome, is extremely low or undetectable. A stimulation of complementation by a factor of 10 to 40 was found when the same defective prophage was situated on a F' factor. A possible explanation for this "episome" effect will be discussed.
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Rao RN, Pereira MG. Behavior of a hybrid F' ts114 lac+, his+ factor (F42-400) in Klebsiella pneumoniae M5a1. J Bacteriol 1975; 123:792-805. [PMID: 1099077 PMCID: PMC235799 DOI: 10.1128/jb.123.3.792-805.1975] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Episome F' ts114 lac+, his+ (F42-400) was transferred from Salmonella typhimurium to Klebsiella pneumoniae. From the progeny, a strain of K. pneumoniae able to retransfer the episome was obtained. The His+ phenotype in this strain is temperature sensitive. Escherichia coli female-specific phages phiII, W31, and T3 were shown to plate on K. pneumoniae. From phiII we obtained two derivatives; phiIIK, which plates only on K. pneumoniae, and phiIIE, which plates only on E. coli. Growth of phages T3 and phiIIK was inhibited by F42-400 in K. pneumoniae. Growth in presence of acridine orange in a defined medium at 40 C resulted in a high level of curing. The frequency of His+ cells after growth in acridine orange at 40 C was 0.001%. An extensive search to detect chromosome mobilization by F42-400 in K. pneumoniae, under different experimental conditions, was negative. We cannot exclude the possibility that the low transfer efficiencies prevented our detection of chromosome mobilization. A search among temperature-resistant, acridine orange-curing-resistant, or galactose-resistant derivatives of the K. pneumoniae donor strain failed to reveal any chromosome transfer. Our failure to detect Hfr's may be a result of: (i) the peculiarity of episome F42-400, (ii) the peculiarity of K. pneumoniae chromosome, or (iii) low transfer efficiency. K. pneumoniae-modified F42-400 and phage 424 were restricted by E. Coli K-12. E. coli K-12-modified episome F42-400 and phage 424 were restricted by K. pneumoniae. E. coli C failed to restrict F42-400 modified with K. pneumoniae specificity. The ability of K. pneumoniae to accept F42-400 is less, by about a factor of 50, than that of E. coli C. As an explanation for the differences in the behavior of E. coli C and K. pneumoniae in ability to receive F42-400 it was suggested that recipient bacteria have specific sites for interaction with the F-pilus tip; these are present in E. Coli C, leading to high transfer efficiency, whereas they may not be present (or if present, are not accessible) in K. pneumoniae, leading to low transfer efficiency.
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Faelen M, Toussaint A, De Lafonteyne J. Model for the enchancement of lambde-gal integration into partially induced Mu-1 lysogens. J Bacteriol 1975; 121:873-82. [PMID: 1090605 PMCID: PMC246014 DOI: 10.1128/jb.121.3.873-882.1975] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Temperate phage Mu-1, which is able to integrate at random in its host chromosome, is also able to mediate integration of other circular deoxyribonucleic acid, as a lambda-gal mutant unable to integrate by itself. After mixed infection with lambda-gal and Mucplus, galplus transductants are recovered that have the lambda-gal integrated in any circular permutation, sandwiched between two complete Mu genomes in the same orientation, the whole Mu-lambda-gal-Mu structure being found at any location in the bacterial chromosome. Here we show that such a lambda-gal can integrate in an induced Mu lysogen. In this case the lambda-gal is again in any circular permutation, between two Mu in the same orientation, but it is always located at the site of the original Mu prophage, and the two surrounding Mu have always the same genotype as the original Mu prophage. Active Mu replication functions are not essential for that process to occur. This suggests that bacterial replication may generate two Mu copies that in some way can regenerate a Mu attachment site that recombines with the lambda-gal. A model is presented that accounts for these observations, may be helpful for understanding some complex features of Mu development, and may possibly offer a basis for explaining spontaneous duplications.
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Wijffelman C, van de Putte P. Transcription of bacteriophage mu. An analysis of the transcription pattern in the early phase of phage development. MOLECULAR & GENERAL GENETICS : MGG 1974; 135:327-37. [PMID: 4464448 DOI: 10.1007/bf00271147] [Citation(s) in RCA: 44] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
It has previously been shown that the transcription of Mu is asymmetric and takes place on the heavy DNA strand (Bade, 1972; Wijffelman et al., 1974). The direction of transcription of Mu has now been determined by RNA-DNA hybridizations between purified Mu-RNA and the separated strands of lambda-Mu hybrid phages. The direction of transcription is from the c-gene (immunity gene) end of the heavy strand to the beta-end (immunity distal end) (Fig. 1). Thermo-inducible, defective Mu lysogens, in which the prophage is deleted from the beta-end, have a normal early transcription pattern, but the increase of RNA at later times is absent. A defective lysogen, which contains only the immunity gene c and the genes A and B, still has an early transcription pattern similar to that of the wild-type. Therefore, we conclude that the early RNA is transcribed from that region of the Mu genome. The early Mu-RNA synthesis is negatively regulated with a minimum rate of transcription at 9 minutes after induction. Before the onset of the late RNA synthesis, at about 22 minutes there is a rather long period in which the rate of Mu-RNA synthesis slowly increases. Using DNA strands of lambda-Mu hybrids which contain only that part of the Mu-DNA on which the early RNA synthesis takes place, we have determined that during the first half in the intermediate phase only early genes are transcribed. The amount of Mu-RNA synthesized by a Mu prophage carrying the X-mutation, which influences the excision of Mu, is greatly reduced. Negative regulation of early transcription occurs normally in this mutant.
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Wijffelman C, Gassler M, Stevens WF, van de Putte P. On the control of transcription of bacteriophage Mu. MOLECULAR & GENERAL GENETICS : MGG 1974; 131:85-96. [PMID: 4420740 DOI: 10.1007/bf00266145] [Citation(s) in RCA: 77] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Abstract
Genetic engineering has quite rightly an image of science fiction. The time when new species with any wanted combination of genetic properties can be ordered from an animal or plant breeding factory seems far away. The layman's view that the science fiction of today is the reality of tomorrow is certainly an insufficient argument to justify optimism. If this were so, we should by now be able to produce hybrids between members of the animal and plant kingdom as was foreseen by a nineteenth-century equivalent of Fred Hoyle (see Fig. I). Despite the scepsis expressed by the prominent scientist Si.r Macfarlane Burnet in his bookGenes, Dreams and Realities(1971), recent advances in molecular genetics have raised new enthusiasm (and uneasiness) which make people speak of genetic engineering as something to aim at as an approach to correct inborn errors of metabolism. This will, however, not be our principal dish if we restrict ourselves to a vegetarian menu. We view genetic engineering of plants not only as a future method to improve species, but also as a fundamental approach to the study of gene expression, especially with respect to cell differentiation. If we consider the term literally, the definition of genetic engineering might be any intentional genetic manipulation to alter species or to make new ones. In this sense genetic engineering was practised long before Mendel presented his laws (1865). In the seventeenth century the bulb growers of the Low Countries produced new varieties of tulips for which prices of a thousand forms each were paid (at the 1636 price index!). We notice here already a strong impact of genetic engineering on society; the so-called crazy tulip trade caused a financial disaster on the Amsterdam stock-exchange comparable to the Wall Street crash in the 1930s.
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de Graaff J, Kreuning PC, van de Putte P. Host controlled restriction and modification of bacteriophage Mu and Mu-promoted chromosome mobilization in Citrobacter freundii. MOLECULAR & GENERAL GENETICS : MGG 1973; 123:283-8. [PMID: 4581370 DOI: 10.1007/bf00271245] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Faelen M, Toussaint A. Isolation of conditional defective mutants of temperate phage Mu-1 and deletion mapping of the Mu-1 prophage. Virology 1973; 54:117-24. [PMID: 4576742 DOI: 10.1016/0042-6822(73)90121-9] [Citation(s) in RCA: 45] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Wijffelman CA, Westmaas GC, van de Putte P. Similarity of vegetative map and prophage map of bacteriophage Mu-1. Virology 1973; 54:125-34. [PMID: 4576743 DOI: 10.1016/0042-6822(73)90122-0] [Citation(s) in RCA: 39] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Toussaint A, Faelen M. Connecting two unrelated DNA sequences with a Mu dimer. NATURE: NEW BIOLOGY 1973; 242:1-4. [PMID: 4571104 DOI: 10.1038/newbio242001a0] [Citation(s) in RCA: 36] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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