Morphogenesis of bacteriophage T4 in extracts of mutant-infected cells.

Edgar, R. S.; Wood, William B.

doi:10.1073/pnas.55.3.498

Cited by 202 publications

(85 citation statements)

References 4 publications

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“…In the assembly pathway, the head, tail and tail fibers are assembled indepen-dently. A head and tail are associated, and then the six tail fibers attach to the baseplate (250).…”

Section: T4 Particle Infection and Lysismentioning

confidence: 99%

Bacteriophage T4 Genome

Miller

Kutter

Mosig

et al. 2003

Microbiol Mol Biol Rev

704

801

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SUMMARY Phage T4 has provided countless contributions to the paradigms of genetics and biochemistry. Its complete genome sequence of 168,903 bp encodes about 300 gene products. T4 biology and its genomic sequence provide the best-understood model for modern functional genomics and proteomics. Variations on gene expression, including overlapping genes, internal translation initiation, spliced genes, translational bypassing, and RNA processing, alert us to the caveats of purely computational methods. The T4 transcriptional pattern reflects its dependence on the host RNA polymerase and the use of phage-encoded proteins that sequentially modify RNA polymerase; transcriptional activator proteins, a phage sigma factor, anti-sigma, and sigma decoy proteins also act to specify early, middle, and late promoter recognition. Posttranscriptional controls by T4 provide excellent systems for the study of RNA-dependent processes, particularly at the structural level. The redundancy of DNA replication and recombination systems of T4 reveals how phage and other genomes are stably replicated and repaired in different environments, providing insight into genome evolution and adaptations to new hosts and growth environments. Moreover, genomic sequence analysis has provided new insights into tail fiber variation, lysis, gene duplications, and membrane localization of proteins, while high-resolution structural determination of the “cell-puncturing device,” combined with the three-dimensional image reconstruction of the baseplate, has revealed the mechanism of penetration during infection. Despite these advances, nearly 130 potential T4 genes remain uncharacterized. Current phage-sequencing initiatives are now revealing the similarities and differences among members of the T4 family, including those that infect bacteria other than Escherichia coli. T4 functional genomics will aid in the interpretation of these newly sequenced T4-related genomes and in broadening our understanding of the complex evolution and ecology of phages—the most abundant and among the most ancient biological entities on Earth.

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“…In the assembly pathway, the head, tail and tail fibers are assembled indepen-dently. A head and tail are associated, and then the six tail fibers attach to the baseplate (250).…”

Section: T4 Particle Infection and Lysismentioning

confidence: 99%

Bacteriophage T4 Genome

Miller

Kutter

Mosig

et al. 2003

Microbiol Mol Biol Rev

704

801

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Section: Introductionmentioning

confidence: 99%

“…Thus, for bacteriophage T4, we know a great deal about the pathways of assembly of tail fibers (1-4), baseplates, sheaths, and cores of the tail (5-9) and assembly of the head (10). These advances have been aided greatly by the development by Edgar and Wood of methods for performing these reactions in cell-free extracts (11,12).The DNA of several bacteriophages (T4, T7, X, and P22) has been shown to replicate as molecules that are several times longer than the DNA found inside the head of the mature virus (13)(14)(15)(16)(17). It is also known that maturation of these long chains of DNA to monomeric units is closely coupled to the formation of the phage head, since cells infected with mutants that are defective in head formation accumulate these long molecules of immature DNA (18-21).…”

mentioning

confidence: 99%

Packaging and Maturation of DNA of Bacteriophage T7 In Vitro

Kerr¹,

Sadowski²

1974

Proc. Natl. Acad. Sci. U.S.A.

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We have developed an in vitro complementation assay to demonstrate packaging and maturation of DNA of phageT7. Cells of Escherichia coli B infected with an appropriate T7 amber mutant are concentrated 200-fold and iysed by freezing and thawing. Two extracts from cells infected with different amber mutants are mixed and incubated at 300. Positive complementation results in a 100-fold increase in phage titer.Using this assay we have demonstrated the packaging of phage DNA from an extract that contains no phage heads (gene 9-, 10-), within head structures present in an extract that contains no phage DNA (gene 5-). We have also demonstrated an activity in extracts that contain no phage DNA or heads (gene 5-,9, 10-), which complements gene 19-infected cells. We have proven that this activity is due to the gene-19 product by showing that the activity is temperature-sensitive if the extract is made from cells infected with a mutant having a temperature-sensitive mutation in gene 19. This assay should be useful in elucidating the mechanism of packaging and maturation of DNA of phage T7.In recent years there has been rapid progress in our understanding of the mechanisms by which complex bacteriophages are assembled. Thus, for bacteriophage T4, we know a great deal about the pathways of assembly of tail fibers (1-4), baseplates, sheaths, and cores of the tail (5-9) and assembly of the head (10). These advances have been aided greatly by the development by Edgar and Wood of methods for performing these reactions in cell-free extracts (11,12).The DNA of several bacteriophages (T4, T7, X, and P22) has been shown to replicate as molecules that are several times longer than the DNA found inside the head of the mature virus (13)(14)(15)(16)(17). It is also known that maturation of these long chains of DNA to monomeric units is closely coupled to the formation of the phage head, since cells infected with mutants that are defective in head formation accumulate these long molecules of immature DNA (18-21).However, our knowledge of the molecular mechanisms whereby the immature phage DNA enters the head ("DNA packaging") and is cleaved to monomeric length ("DNA maturation") has been limited, in part, by the inability to perform these reactions in vitro. Recently, however, assays have been developed to demonstrate packaging of phage DNA in vitro. Kaiser and Masuda (22) showed that exogenous lambda DNA could be packaged by extracts from induced lysogens and Hohn and Hohn (23) have demonstrated that head-related particles containing no DNA ("petit lambda") can be filled with DNA in vitro. Finally, the experiments of Pruss, Goldstein, and Calendar (24) showed that the size of the head of phage P2 is determined solely by the proteins involved and not by the phage DNA.Bacteriophage T7 may be a convenient system in which to study DNA packaging and maturation because it is a 3545 relatively simple virus for which there is a great deal of information about its genetics and physiology (25). The DNA of phage T7 is a unique, terminall...

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“…In bacteriophage T4D+, these mutants have allowed the role of specific structures in the assembly pathway to be determined (4,5). Several potential intermediates in head morphogenesis (6)(7)(8)(9) that are found at the terminal steps of head maturation have been isolated.…”

mentioning

confidence: 99%

Bacteriophage T4 Head Morphogenesis. Isolation, Partial Characterization, and Fate of Gene 21-Defective Tau-Particles

Luftig

Lundh

1973

Proc. Natl. Acad. Sci. U.S.A.

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A lysozyme-detergent procedure was developed for isolation of tau-particles from cells infected by gene-21 mutants of T4 bacteriophage. These particles have a sedimentation coefficient of 440 h 10 S. They contain less than 1% detectable nuclease-resistant DNA, are smaller (650 X 850 A) than normal bacteriophage heads (800 X 1100 A), and exhibit two major bands on 7.5% Na dodecyl sulfate-acrylamide gels. The more prominent band (55,000 daltons) corresponds to the uncleaved, major capsid polypeptide (P23); the other band (32,000 daltons) corresponds to the gene-22 product (P22). Temperatureshift experiments with cells infected with tsN8 (gene 21) mutants were used to study the fate of tau-particles accumulated under nonpermissive conditions. 50 Min after ts N8-infected cells were shifted from the nonpermissive (41.50) to the permissive (250) temperature, a phage burst occurred that was 75% of that observed with wild-type phage. However, in "pulse-chase" temperature-shift experiments, the radioactive tau-particle peak only slightly decreased (by 10-14%) by 50 min after the shift, whereas an increased amount of radioactivity (about four times as much as the tau-particle decrease) appeared in phage particles. The results suggest that at least two pools of head polypeptides coexist in cells infected with gene-21 mutants. One pool is composed of head subunits assembled into tau-particles, which are mostly aberrant structures; the second pool is composed of head subunits that are incorporated into mature phage when the gene-21 product becomes functional.

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Morphogenesis of bacteriophage T4 in extracts of mutant-infected cells.

Cited by 202 publications

References 4 publications

Bacteriophage T4 Genome

Bacteriophage T4 Genome

Packaging and Maturation of DNA of Bacteriophage T7 In Vitro

Bacteriophage T4 Head Morphogenesis. Isolation, Partial Characterization, and Fate of Gene 21-Defective Tau-Particles

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