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Volokhina I, Gusev Y, Mazilov S, Moiseeva Y, Chumakov M. Computer evaluation of VirE2 protein complexes for ssDNA transfer ability. Comput Biol Chem 2017; 68:64-70. [DOI: 10.1016/j.compbiolchem.2017.01.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Revised: 01/23/2017] [Accepted: 01/23/2017] [Indexed: 11/16/2022]
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2
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Chumakov MI. Protein apparatus for horizontal transfer of agrobacterial T-DNA to eukaryotic cells. BIOCHEMISTRY (MOSCOW) 2013; 78:1321-32. [DOI: 10.1134/s000629791312002x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Baughn AD, Malamy MH. The essential role of fumarate reductase in haem-dependent growth stimulation of Bacteroides fragilis. MICROBIOLOGY (READING, ENGLAND) 2003; 149:1551-1558. [PMID: 12777495 DOI: 10.1099/mic.0.26247-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Haem is required for optimal growth of the bacterial anaerobe Bacteroides fragilis. Previous studies have shown that growth in the presence of haem is coincident with increased yields of ATP from glucose, expression of b-type cytochromes and expression of fumarate reductase activity. This paper describes the identification of the genes that encode the cytochrome, iron-sulfur cluster protein and flavoprotein of the B. fragilis fumarate reductase. These genes, frdC, frdA and frdB, respectively, are organized in an operon. Nonpolar, in-frame deletions of frdC and frdB were constructed in the B. fragilis chromosome. These mutant strains had no detectable fumarate reductase or succinate dehydrogenase activity. In addition, the frd mutant strains showed a threefold increase in generation time, relative to the wild-type strain. Growth of these mutant strains was fully restored to the wild-type rate by the introduction of a B. fragilis replicon containing the entire frd operon. Growth of the frd mutant strains was partially restored by supplementing the growth medium with succinate, indicating that the frd gene products function as a fumarate reductase. During growth on glucose, the frd mutant strains showed a threefold decrease in cell mass yield, relative to the wild-type strain. These data indicate that fumarate reductase is important for both energy metabolism and succinate biosynthesis in B. fragilis.
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Affiliation(s)
- Anthony D Baughn
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, 136 Harrison Avenue, Boston, MA 02111, USA
| | - Michael H Malamy
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, 136 Harrison Avenue, Boston, MA 02111, USA
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Bergquist PL, Saadi S, Maas WK. Distribution of basic replicons having homology with RepFIA, RepFIB, and RepFIC among IncF group plasmids. Plasmid 1986; 15:19-34. [PMID: 2869535 DOI: 10.1016/0147-619x(86)90011-9] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Plasmids encoding F-like pili have been divided into groups on the basis of their incompatibility behavior. Three basic replicons have been recognized previously in the IncFI plasmid group and we have now examined their distribution in representative plasmids from 22 of the currently recognized incompatibility groups. The occurrence of these basic replicons was found to be rare outside of the IncF group, and significant hybridization was shown only for RepFIA to IncH1 and I group plasmids. Homology to the RepFIC basic replicon was found in all but one of the IncF group plasmids examined but RepFIA and RepFIB have a more restricted distribution. It appears likely that some plasmids carry vestiges of replicons which still express incompatibility but are incapable of replication. We suggest that evolutionary divergence among the plasmids of the IncF group has resulted from various genetic rearrangements among these basic replicons.
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Rotman GS, Cooney R, Malamy MH. Cloning of the pif region of the F sex factor and identification of a pif protein product. J Bacteriol 1983; 155:254-64. [PMID: 6305912 PMCID: PMC217676 DOI: 10.1128/jb.155.1.254-264.1983] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
This paper reports a detailed investigation of the pif region of the F factor responsible for inhibition of development of T7 and related "female-specific" phages. We have mapped a series of pif::Tn5 insertions to a region between 39.6 and 42.8 kilobases on the physical map of F. All pif::Tn5 insertions plated T7 at full efficiency; most were clustered in a 1.8-kilobase interval on both sides of the EcoRI site located at F coordinate 40.3 kilobases. A 5.2-kilobase Pst-I fragment with F coordinates 38.9 to 44.1 has been cloned into a pSC101 vector to create the Pif+ plasmid pGS103. A series of Pif- deletion mutants and nonsense mutants were isolated from pGS103. Using minicells carrying pGS103 or its derivatives, we have identified a 70,000-dalton pif protein.
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Abstract
Several F' plasmids encoding resistance to tetracycline have been derived from a trg::Tn10 Hfr B7 strain of Escherichia coli K-12. One of these plasmids, JGF312, was analyzed by restriction endonuclease digestion and Southern blot hybridization to cloned chromosomal fragments. This analysis revealed that JGF312 was formed by Tn10-promoted deletion from the Tn10 insertion (31.4 min) to within the prophage rac at 30.1 min. Hfr B7 was shown to result from recombination between IS2 of F delta (33-43) and a chromosomal IS2 located within the rac-man region at 30.9 min on the genetic map.
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Kilbane JJ, Malamy MH. F factor mobilization of non-conjugative chimeric plasmids in Escherichia coli: general mechanisms and a role for site-specific recA-independent recombination at orV1. J Mol Biol 1980; 143:73-93. [PMID: 7003164 DOI: 10.1016/0022-2836(80)90125-4] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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Gardner RC, Caughey PA, Lane D, Bergquist PL. Replication mutants of the F-plasmid of Escherichia coli. II. Cloned replication regions of temperature-sensitive mutants. Plasmid 1980; 3:179-92. [PMID: 6765557 DOI: 10.1016/0147-619x(80)90108-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Abstract
Eight new F' plasmids derived from Hfr strains in which F is integrated at the chromosomal element alpha 3 beta 3 have been isolated and subjected to restriction enzyme, hybridization, and electron microscope heteroduplex analysis. Plasmids carrying extensive amounts of bacterial deoxyribonucleic acid were produced even though they were obtained by selection for transfer of lac, which is closely linked to F in the parental Hfr strains. Seven plasmids were type II Flac+ proC+ purE+ plasmids, and one was a type I Flac+ proC+ plasmid. Five of the Flac+ proC+ purE+ plasmids contain approximately 284 kilobases of bacterial deoxyribonucleic acid, which is identical for all five within the resolution of the restriction enzyme analysis. Theses results indicate that type II F' plasmids are the predominant tra+ F' type from this region of the Escherichia coli K-12 chromosome and that the recombination events leading to formation of these plasmids exhibit site specificity.
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Krüger DH, Hansen S, Presber W, Rudolph M, Scholz D, Rosenthal HA. [Host range relationship of bacteriophages T3 and T7 with Escherichia coli K 12 strains]. ZEITSCHRIFT FUR ALLGEMEINE MIKROBIOLOGIE 1979; 19:473-80. [PMID: 94721 DOI: 10.1002/jobm.3630190704] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The closely related phages T3 and T7 exhibit different growth patterns on Escherichia coli W hosts cells (E. coli K12 derivatives). T7 grows normally while T3 does not adsorb. T3hw mutants displaying a T7-like host range were isolated and described.
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Carrigan JM, Helman ZM, Krishnapillai V. Transfer-deficient mutants of the narrow-host-range plasmid R91-5 of Pseudomonas aeruginosa. J Bacteriol 1978; 135:911-9. [PMID: 99439 PMCID: PMC222464 DOI: 10.1128/jb.135.3.911-919.1978] [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: 12/13/2022] Open
Abstract
Three methods have been successful in the isolation of transfer-deficient mutants of the narrow-host-range R plasmid R91-5 of Pseudomonas aeruginosa: (i) selection for donor-specific phage resistance; (ii) direct screening after mutagenic treatment with either ethyl methane sulfonate or N-methyl-N'-nitro-N-nitrosoguanidine; (iii) in vitro mutagenesis of plasmid DNA by hydroxylamine followed by transformation and direct screening. The majority of transfer-deficient mutants were donor-specific phage resistant, supporting the view that sex pili and other surface components are essential for conjugal transfer (since the phages PRD1 and PR4 adsorb to these sites). Some of the transfer-deficient mutants were also unable to inhibit the replication of phage G101 or lost entry exclusion or both phenotypes. The ability to revert these pleiotropic mutants to wild type implicates the latter two functions in R91-5 transfer. Suppressor mutations in P. aeruginosa enabled the detection of suppressor-sensitive, transfer-deficient mutants. Such mutants should prove useful in conjugational complementation tests for the identification of the transfer cistrons of R91-5.
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Achtman M, Skurray RA, Thompson R, Helmuth R, Hall S, Beutin L, Clark AJ. Assignment of tra cistrons to EcoRI fragments of F sex factor DNA. J Bacteriol 1978; 133:1383-92. [PMID: 346570 PMCID: PMC222176 DOI: 10.1128/jb.133.3.1383-1392.1978] [Citation(s) in RCA: 79] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
We describe here the cloning of single EcoRI fragments from the tra region of F DNA using ColE1::Tn3 as vector. These plasmids, as well as the series of Skurray et al. (Proc. Natl. Acad. Sci. U.S.A. 73:64-68, 1976), have been used to refine the map positions of tra cistrons on the F factor as well as to define a new DNA transfer cistron, traM. The current map of the tra cistrons is presented. None of the known tra cistrons, with the exception of traG, straddles an EcoRI site. The EcoRI site at 82 kilobases splits the traG cistron into two portions, an operator-proximal portion necessary for F pilus synthesis and an operator distal portion involved in conjugation itself. The operon structure of the tra cistrons was reevaluated, and we found that traI is at least partially independent of transcription of the traA to traD operon.
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Rowbury RJ. Bacterial plasmids with particular reference to their replication and transfer properties. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 1978; 31:271-317. [PMID: 323920 DOI: 10.1016/0079-6107(78)90011-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Guyer MS, Davidson N, Clark AJ. Heteroduplex analysis of tra delta f' plasmids and the mechanism of their formation. J Bacteriol 1977; 131:970-80. [PMID: 330507 PMCID: PMC235555 DOI: 10.1128/jb.131.3.970-980.1977] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Four tra delta FargG+ plasmids, derived from matings between Hfr AB312 and a recA recipient, have been shown to have deletions of at least 50% of the F genome, including the region in which the tra genes map. The mutant plasmids do contain the F genes required for plasmid maintenance. Correlations can be made between, on the one hand, the F genes present on the tradelta F' plasmids and the F genes transferred early by an Hfr donor, and, on the other hand, the F genes deleted from the tradelta F' plasmids and the F genes transferred late by an Hfr donor. A biased representation of proximally and distally transferred chromosomal markers among the tradelta F' elements was also demonstrated. Taken Taken together, the asymmetrical representation of Hfr genes and the cis dominance of the Tra phenotype of these mutants can best be explained by the hypothesis that the tradelta F' plasmids are formed by repliconation of the transferred exogenote in a recA recipient.
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Deonier RC, Davidson N. The sequence organization of the integrated F plasmid in two Hfr strains of Escherichia coli. J Mol Biol 1976; 107:207-22. [PMID: 794483 DOI: 10.1016/s0022-2836(76)80002-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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18
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Guyer MS, Figurski D, Davidson N. Electron microscope study of a plasmid chimera containing the replication region of the Escherichia coli F plasmid. J Bacteriol 1976; 127:988-97. [PMID: 783125 PMCID: PMC233009 DOI: 10.1128/jb.127.2.988-997.1976] [Citation(s) in RCA: 37] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
pML31, a plasmid chimera constructed to contain the replication genes of an Flac plasmid, has been studied by electron microscope methods. Heteroduplex analysis shows that the only F sequence present in pML31 is that with corrdinates 40.3-49.3F. This region has previously been identified as essential for plasmid maintenance. The sequence of pML31, which was derived originally from R6-5, carries the km gene(s) and an inverted duplication of a 1.0-kilobase sequence. On the basis of length measurements, the repeated sequence is different from IS1, IS2, IS3, and an inverted repeat associated with the km gene(s) of plasmid JR67.
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Guyer MS, Clark AJ. cis-Dominant, transfer-deficient mutants of the Escherichia coli K-12 F sex factor. J Bacteriol 1976; 125:233-47. [PMID: 1107307 PMCID: PMC233357 DOI: 10.1128/jb.125.1.233-247.1976] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Rare conjugational progeny formed by crossing each of five Hfr strains with a recA-F- strain have been characterized. Selection was made for a proximal Hfr marker, taking strict precautions to prevent transfer of recA+ to the zygotes. Most of the progeny were found to be F' strains containing deletion mutant plasmids. With two exceptions, these mutant plasmids have lost all of the tra genes, which are required to confer conjugational donor ability upon a host. In addition, all but the exceptional mutant plasmids were found to be very poorly transmissible from transient heterozygotes which also contain a wild-type F' plasmid. The poor transmissibility is a cis-dominant transfer-defective phenotype which may result from deletion of all or part of the origin of transfer replication (ori), or of a gene determining a cis-acting protein. The two exceptional mutant plasmids may carry short deletions of some of the tra genes or polar tra mutations. The remaining progeny were nonmutant F' strains and F- strains. The frequency with which the F- strains were recovered permits us to estimate that the maximum amount of recombination possible in a recA56 zygote is 10(-6) that of a recA+ zygote.
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Skurray RA, Nagaishi H, Clark AJ. Molecular cloning of DNA from F sex factor of Escherichia coli K-12. Proc Natl Acad Sci U S A 1976; 73:64-8. [PMID: 1108020 PMCID: PMC335839 DOI: 10.1073/pnas.73.1.64] [Citation(s) in RCA: 85] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
We describe the molecular cloning of various DNA segments generated by partial EcoRI endonuclease digestion of the sex factor F. These segments have been analyzed by agarose gel electrophoresis of EcoRI digests and were arranged in a series of overlapping fragments using the EcoRI fragment map of F established by H. Ohtsubo and E. Ohtsubo. The clones isolated demonstrate one or more of the following F-specified functions: inhibition of female-specific phage (T7) multiplication, formation of F pili, surface exclusion, or immunity to lethal zygosis. These properties are discussed in terms of the EcoRI fragments of F that specify them.
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22
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Santos DS, Palchaudhuri S, Maas WK. Genetic and physical characteristics of an enterotoxin plasmid. J Bacteriol 1975; 124:1240-7. [PMID: 1104580 PMCID: PMC236033 DOI: 10.1128/jb.124.3.1240-1247.1975] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
We are engaged in the genetic and physical characterization of an enterotoxin (Ent) plasmid, Ent P307, which contains genes for the production of a hear-labile and a heat-stable enterotoxin. We are using an Escherichia coli K-12 strain, 711 (P307), constructed by S. Falkow, which contains no other plasmids besides Ent P307. Our genetic studies have shown that the plasmid is incompatible with the sex factor F, both in the integrated (Hfr) and the autonomous (F-prime) state. Ent P307 can thus be assigned to incompatibility group FI. An R factor, R386, which belongs to the same incompatibility group, was also found to be incompatibile with Ent P307, whereas five other R factors belonging to different incompatibility groups were compatible with Ent P307. In the presence of Ent P307, conjugal transfer and sensitivity to a male-specific phage of a derepressed F-like R factor, R1drd19, were repressed. Ent P307 is, thus, finO+. Presumably, it also causes repression of its own transfer genes since conjugal transfer of Ent P307 could not be demonstrated. Unlike F, it does not restrict the growth of female-specific phage phiII. From physical studies on extracted deoxyribonucleic acid, the molecular weight of Ent P307 was determined to be 54 X 10(6). By electron microscope heteroduplex analysis, the plasmid was found to be homologous with F in four regions, encompassing about half of its length. One long region and two short ones contain genes for conjugal transfer; the other short region carries genes for replication and incompatibility.
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Ponta H, Pon CL, Herrlich P, Gualerzi C, Hirsch-Kauffmann M, Pfennig-Yeh ML, rahmsdorf HJ, Schweiger M. The sex-factor-dependent exclusion of coli virus T7. EUROPEAN JOURNAL OF BIOCHEMISTRY 1975; 59:261-70. [PMID: 1204611 DOI: 10.1111/j.1432-1033.1975.tb02450.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The cause of T7 exclusion by the F episome was investigated. Extracts from neither normal nor infected F+ cells contained an inhibitor of gene expression in vitro. The protein synthesizing systems prepared in vitro from these cells supported T7 early and late protein synthesis with normal efficiency. The content of translational initiation factors in F- and F+ cells, both noninfected and infected, was almost identical. The episome-dependent block of T7 gene expression was observed only in intact cells and detailed kinetics of gene expression in vivo revealed a stop of all transcription and translation at or just before 11 min after T7 infection. The mechanism of F+-dependent T7 exclusion involves both episomal and viral gene products. The data indicate that a T7-induced membrane alteration of the F+ cell membrane leads to cessation of T7 development as well as to the death of the host cell ('suicide').
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Condit RC. F factor-mediated inhibition of bacteriophage T7 growth: increased membrane permeability and decreased ATP levels following T7 infection of male Escherichia coli. J Mol Biol 1975; 98:45-59. [PMID: 1104868 DOI: 10.1016/s0022-2836(75)80100-8] [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: 12/25/2022]
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Britton JR, Haselkorn R. Permeability lesions in male Escherichia coli infected with bacteriophage T7. Proc Natl Acad Sci U S A 1975; 72:2222-6. [PMID: 1094459 PMCID: PMC432729 DOI: 10.1073/pnas.72.6.2222] [Citation(s) in RCA: 44] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The abortive development of bacteriophage T7 in E. coli cells carrying F factors has previously been attributed to a lack of virus-directed modification of ribosomes in such cells. We find it unnecessary to postulate such translational control to explain the failure of T7 development. Instead, there is a general cessation of macromolecular syntheses around 8 min after T7 infection of F' cells. This cessation is correlated with a sudden outflow of the entire acid-soluble pool of phosphorus-containing compounds and loss of the ability to accumulate amino acids. Manifestation of these defects requires expression of at least one T7 gene and one episomal gene.
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Hu S, Ohtsubo E, Davidson N. Electron microscopic heteroduplex studies of sequence relations among plasmids of Escherichia coli: structure of F13 and related F-primes. J Bacteriol 1975; 122:749-63. [PMID: 1092667 PMCID: PMC246114 DOI: 10.1128/jb.122.2.749-763.1975] [Citation(s) in RCA: 85] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The structure of F13, a plasmid containing lac, purE, and proC, has been determined by heteroduplex analysis. As expected for an F-prime formed by a type II excision event, it contains all the sequences of F plus a large segment of Escherichia coli chromosomal deoxyribonucleic acid. There is a sequence of F with coordinates 16.3-17.6F which has been shown in other studies to be the insertion sequence IS2. This IS2 occurs twice on F13, once at each of the two junctions of F deoxyribonucleic acid with chromosomal deoxyribonucleic acid. The sequence alpha beta which occurs twice on F with coordinates 93.2-94.5/OF and 13.7-15.0F occurs an additional three times, twice in an inverted order relative to the alpha beta sequences of F, on the chromosomal sequences of F13. The structures of the plasmids F13-4 and F210 have been determined. The common sequences of F13 with F152-1 (a derivative of F152, the classical F2gal) and with F13-4 and F210 have been mapped. These results partially map lac, proC, tsx, and purE on F13. On the basis of all of these results, it is proposed that Hfr 13 (the parent of F13) was formed by recirpocal recombination between IS2 on F and an IS2 resident at a point between lac and proC on the chromosome of the F+ parent of Hfr 13. It is proposed that this IS2 and the several alpha beta sequences on the chromosomal part of F13 are hot spots for recombination with F, i.e., for Hfr formation. The point of origin and direction of transfer of many Hfr's can be explained by this hypothesis. In particular, the sequence relations of F42-1 (Flac) and of F152-1 (F 2gal) with F13 are completely consistent with this model.
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Otsubo E, Lee HJ, Deonier RC, Davidson N. Electron microscope heteroduplex studies of sequence relations among plasmids of Escherichia coli. VI. Mapping of F14 sequences homologous to phi 80dmetBJF and phi 80dargECBH bacteriophages. J Mol Biol 1974; 89:599-618. [PMID: 4615161 DOI: 10.1016/0022-2836(74)90038-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Otsubo E, Deonier RC, Lee HJ, Davidson N. Electron microscope heteroduplex studies of sequence relations among plasmids of Escherichia coli. IV. The F sequences in F14. J Mol Biol 1974; 89:565-84. [PMID: 4615159 DOI: 10.1016/0022-2836(74)90036-9] [Citation(s) in RCA: 66] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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29
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Lee HJ, Otsubo E, Deonier RC, Davidson N. Electron microscope heteroduplex studies of sequence relations among plasmids of Escherichia coli. V. ilv+ Deletion mutants of F14. J Mol Biol 1974; 89:585-97. [PMID: 4615160 DOI: 10.1016/0022-2836(74)90037-0] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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30
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Thompson R, Hughes SG, Broda P. Plasmid identification using specific endonucleases. MOLECULAR & GENERAL GENETICS : MGG 1974; 133:141-9. [PMID: 4614064 DOI: 10.1007/bf00264835] [Citation(s) in RCA: 78] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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