1
|
Maekawa M, Oda T, Hanai R. Biochemical analysis of the replication initiator protein of staphylococcal plasmid pC194. Biochimie 2022; 202:85-93. [PMID: 35988842 DOI: 10.1016/j.biochi.2022.08.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 08/07/2022] [Accepted: 08/15/2022] [Indexed: 11/26/2022]
Abstract
The staphylococcal plasmid pC194 is replicated through the rolling-circle mechanism. Its replication protein RepA has been proposed to initiate replication by making a bond between Y214 and DNA phosphate via transesterification and to terminate it by hydrolyzing DNA with E210 and carrying out strand transfer. We tested this model by examining the catalytic functions of the protein with purified RepA proteins and single-stranded DNA oligomers. The wild-type RepA formed a covalent bond with the DNA phosphate at the predicted initiation site. It hydrolyzed the phosphodiester bond at the site, which activity was found to depend on the presence of a large pseudopalindrome contained in the replication origin. The protein carried out a strand-transfer reaction which mimicked the termination step of replication. A Y214F and an E210A mutant respectively lacked the transesterification and the hydrolytic activity. These results are consistent with the previously proposed model, which was based solely on molecular genetics results. In addition, an E142A mutant was found to lack both activities, suggesting that the residue may coordinate the divalent cation necessary for them. A possible role of the pseudopalindrome in controlling the two activities of RepA during a replication cycle is also discussed.
Collapse
Affiliation(s)
- Michinari Maekawa
- Department of Life Science and Research Center for Life Science, College of Science, Rikkyo University, Tokyo, Japan
| | - Takashi Oda
- Department of Life Science and Research Center for Life Science, College of Science, Rikkyo University, Tokyo, Japan
| | - Ryo Hanai
- Department of Life Science and Research Center for Life Science, College of Science, Rikkyo University, Tokyo, Japan.
| |
Collapse
|
2
|
Abstract
Viruses are the most abundant biological entities on Earth. In addition to their impact on animal and plant health, viruses have important roles in ecosystem dynamics as well as in the evolution of the biosphere. Circular Rep-encoding single-stranded (CRESS) DNA viruses are ubiquitous in nature, many are agriculturally important, and they appear to have multiple origins from prokaryotic plasmids. A subset of CRESS-DNA viruses, the cruciviruses, have homologues of capsid proteins encoded by RNA viruses. The genetic structure of cruciviruses attests to the transfer of capsid genes between disparate groups of viruses. However, the evolutionary history of cruciviruses is still unclear. By collecting and analyzing cruciviral sequence data, we provide a deeper insight into the evolutionary intricacies of cruciviruses. Our results reveal an unexpected diversity of this virus group, with frequent recombination as an important determinant of variability. The discovery of cruciviruses revealed the most explicit example of a common protein homologue between DNA and RNA viruses to date. Cruciviruses are a novel group of circular Rep-encoding single-stranded DNA (ssDNA) (CRESS-DNA) viruses that encode capsid proteins that are most closely related to those encoded by RNA viruses in the family Tombusviridae. The apparent chimeric nature of the two core proteins encoded by crucivirus genomes suggests horizontal gene transfer of capsid genes between DNA and RNA viruses. Here, we identified and characterized 451 new crucivirus genomes and 10 capsid-encoding circular genetic elements through de novo assembly and mining of metagenomic data. These genomes are highly diverse, as demonstrated by sequence comparisons and phylogenetic analysis of subsets of the protein sequences they encode. Most of the variation is reflected in the replication-associated protein (Rep) sequences, and much of the sequence diversity appears to be due to recombination. Our results suggest that recombination tends to occur more frequently among groups of cruciviruses with relatively similar capsid proteins and that the exchange of Rep protein domains between cruciviruses is rarer than intergenic recombination. Additionally, we suggest members of the stramenopiles/alveolates/Rhizaria supergroup as possible crucivirus hosts. Altogether, we provide a comprehensive and descriptive characterization of cruciviruses.
Collapse
|
3
|
Abstract
HUH endonucleases are numerous and widespread in all three domains of life. The major function of these enzymes is processing a range of mobile genetic elements by catalysing cleavage and rejoining of single-stranded DNA using an active-site Tyr residue to make a transient 5'-phosphotyrosine bond with the DNA substrate. These enzymes have a key role in rolling-circle replication of plasmids and bacteriophages, in plasmid transfer, in the replication of several eukaryotic viruses and in various types of transposition. They have also been appropriated for cellular processes such as intron homing and the processing of bacterial repeated extragenic palindromes. Here, we provide an overview of these fascinating enzymes and their functions, using well-characterized examples of Rep proteins, relaxases and transposases, and we explore the molecular mechanisms used in their diverse activities.
Collapse
|
4
|
Freire MA. The Zea mays glycine-rich RNA-binding protein MA16 is bound to a ribonucleotide(s) by a stable linkage. JOURNAL OF PLANT RESEARCH 2012; 125:653-660. [PMID: 22270696 DOI: 10.1007/s10265-012-0476-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2011] [Accepted: 01/03/2012] [Indexed: 05/31/2023]
Abstract
Expression of the gene encoding the maize glycine-rich RNA-binding protein MA16 is developmentally regulated and it is involved in environmental stress responses. The MA16 protein shows a wide spectrum of RNA-binding activities. On the basis of in vivo labelling, where a [³²P]phosphate label was linked to the MA16 protein, Freire and Pages (Plant Mol Biol 29:797-807, 1995) suggested that the protein may be post-translationally modified by phosphorylation. However, further analysis showed that the [³²P]phosphate label was sensitive to different treatments, suggesting that modification distinct from protein phosphorylation might occur in the MA16 protein. Biochemical analysis revealed that this [³²P]phosphate labelling was resistant to phenol extraction and denaturing SDS-PAGE but sensitive to micrococcal nuclease, RNase A and RNase T1 treatments. The mobility of [³⁵S] labelled MA16 protein on SDS-PAGE did not significantly changed after the nuclease treatments suggesting that the [³²P]phosphate label associated to MA16 protein could be a ribonucleotide or a very short ribonucleotide chain. In addition, immunoprecipitation of labelled extracts showed that the ribonucleotide(s) linked to the MA16 protein was removed by phosphorolytic activity. This activity could be catalysed by a phosphate-dependent ribonuclease. The C-terminus of MA16 protein harbouring a glycine-rich domain was predicted to be an intrinsically disordered region.
Collapse
Affiliation(s)
- Miguel Angel Freire
- Facultad de Ciencias Exactas, Físicas y Naturales, Instituto Multidisciplinario de Biología Vegetal, CONICET, Universidad Nacional de Córdoba, Edificio de Investigaciones Biológicas y Tecnológicas, 5000 Córdoba, Argentina.
| |
Collapse
|
5
|
Organization, Replication, Transposition, and Repair of DNA. Biochemistry 2001. [DOI: 10.1016/b978-012492543-4/50030-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
6
|
Männistö RH, Kivelä HM, Paulin L, Bamford DH, Bamford JK. The complete genome sequence of PM2, the first lipid-containing bacterial virus To Be isolated. Virology 1999; 262:355-63. [PMID: 10502514 DOI: 10.1006/viro.1999.9837] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Bacteriophage PM2 was isolated from the Pacific Ocean off the coast of Chile in the late 1960s. It was a new virus type, later classified as Corticoviridae, and also the first bacterial virus for which it was demonstrated that lipids are part of the virion structure. Here we report the determination and analysis of the 10, 079-bp circular dsDNA genome sequence. Noteworthy discoveries are the replication initiation system, which is related to the rolling circle mechanism described for phages such as φX174 and P2, and a 1.2-kb sequence that is similar to the maintenance region of a plasmid found in a marine Pseudoalteromonas sp. strain A28.
Collapse
Affiliation(s)
- R H Männistö
- Department of Biosciences and Institute of Biotechnology, Viikki Biocenter, Helsinki, FIN-00014, Finland
| | | | | | | | | |
Collapse
|
7
|
Asano S, Higashitani A, Horiuchi K. Filamentous phage replication initiator protein gpII forms a covalent complex with the 5' end of the nick it introduced. Nucleic Acids Res 1999; 27:1882-9. [PMID: 10101197 PMCID: PMC148397 DOI: 10.1093/nar/27.8.1882] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Rolling circle type DNA replication is initiated by introduction of a nick in the leading strand of the origin by the initiator protein, which in most cases binds covalently to the 5' end of the nick. In filamentous phage, however, such a covalent complex has not been detected. Using a suitable substrate and short reaction time, we show that filamentous phage initiator gpII forms a covalent complex with nicked DNA, which rapidly dissociates unless gpII is inactivated. A peptide-DNA complex was isolated from trypsin digest of the complex by ion-exchange column chromatography and gel filtration, and its peptide sequence was determined. The result indicated that gpII was linked to DNA by the tyrosine residue at position 197 from the N-terminus. The mutant protein in which this tyrosine was replaced by phenylalanine did not show any detectable activity to complement gene II amber mutant phage in vivo. In vitro, the mutant protein recognized the origin and bent DNA as well as the wild-type does, but failed to introduce a nick and to relax the superhelicity of cognate DNA.
Collapse
Affiliation(s)
- S Asano
- Division of Microbial Genetics, National Institute of Genetics, Mishima 411-8540, Japan
| | | | | |
Collapse
|
8
|
Wittschieben J, Petersen BO, Shuman S. Replacement of the active site tyrosine of vaccinia DNA topoisomerase by glutamate, cysteine or histidine converts the enzyme into a site-specific endonuclease. Nucleic Acids Res 1998; 26:490-6. [PMID: 9421505 PMCID: PMC147276 DOI: 10.1093/nar/26.2.490] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Vaccinia topoisomerase forms a covalent protein-DNA intermediate at 5'-CCCTT downward arrow sites in duplex DNA. The T downward arrow nucleotide is linked via a 3'-phosphodiester bond to Tyr-274 of the enzyme. Here, we report that mutant enzymes containing glutamate, cysteine or histidine in lieu of Tyr-274 catalyze endonucleolytic cleavage of a 60 bp duplex DNA at the CCCTT downward arrow site to yield a 3' phosphate-terminated product. The Cys-274 mutant forms trace levels of a covalent protein-DNA complex, suggesting that the DNA cleavage reaction may proceed through a cysteinyl-phosphate intermediate. However, the His-274 and Glu-274 mutants evince no detectable accumulation of a covalent protein-DNA adduct. Glu-274 is the most active of the mutants tested. The pH dependence of the endonuclease activity of Glu-274 (optimum pH = 6.5) is distinct from that of the wild-type enzyme in hydrolysis of the covalent adduct (optimum pH = 9.5). At pH 6.5, the Glu-274 endonuclease reaction is slower by 5-6 orders of magnitude than the rate of covalent adduct formation by the wild-type topoisomerase, but is approximately 20 times faster than the rate of hydrolysis by the wild-type covalent adduct. We discuss two potential mechanisms to account for the apparent conversion of a topoisomerase into an endonuclease.
Collapse
Affiliation(s)
- J Wittschieben
- Molecular Biology Program, Sloan-Kettering Institute, New York, NY 10021, USA
| | | | | |
Collapse
|
9
|
Abstract
The RepA protein of plasmid pC194 initiates and terminates rolling circle replication. At initiation, it forms a 5'-phosphotyrosyl DNA link, whereas at termination, a glutamate residue directs hydrolytic cleavage of the newly synthesized origin, and the resulting 3'-hydroxyl group undergoes transesterification with the phosphotyrosine link. The protein is thus released from DNA, and the termination is uncoupled from reinitiation of replication. Replacement of the glutamate with tyrosine in RepA altered this mechanism, so that termination occurred by two successive transesterifications and became coupled to reinitiation. This result suggests that various enzymes involved in DNA cleavage and rejoining may have similar mechanistic and evolutionary roots.
Collapse
Affiliation(s)
- M F Noirot-Gros
- Génétique Microbienne, Institut National de la Recherche Agronomique, Domaine de Vilvert, 78352 Jouy en Josas Cedex, France
| | | |
Collapse
|
10
|
Leschziner AE, Boocock MR, Grindley ND. The tyrosine-6 hydroxyl of gamma delta resolvase is not required for the DNA cleavage and rejoining reactions. Mol Microbiol 1995; 15:865-70. [PMID: 7596288 DOI: 10.1111/j.1365-2958.1995.tb02356.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Site-specific recombinases of the resolvase and DNA invertase family all contain a tyrosine residue close to the N-terminus, and four residues away from a serine that has been implicated in catalysis of DNA strand breakage and reunion. To examine the role of this tyrosine in recombination, we have constructed a mutant of gamma delta resolvase in which the tyrosine (residue 6) is replaced by phenylalanine. Characterization of the Y6F mutant protein in vitro indicated that although it was highly defective in recombination, it could cleave DNA at the cross-over site, form a covalent resolvase-DNA complex and rejoin the cleaved cross-over site (usually restoring the parental site). These data rule out a direct role of the Tyr-6 hydroxyl as the nucleophile in the DNA cleavage reaction and strengthen the conclusion that this nucleophile is the nearby invariant serine residue, Ser-10. We conclude that Tyr-6 is essential for fully co-ordinated strand cleavage and exchange, but is dispensable for individual strand cleavage and religation reactions.
Collapse
Affiliation(s)
- A E Leschziner
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, USA
| | | | | |
Collapse
|
11
|
Christiansen K, Knudsen B, Westergaard O. The covalent eukaryotic topoisomerase I-DNA intermediate catalyzes pH-dependent hydrolysis and alcoholysis. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(19)78134-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
12
|
Hanai R, Wang J. The mechanism of sequence-specific DNA cleavage and strand transfer by phi X174 gene A* protein. J Biol Chem 1993. [DOI: 10.1016/s0021-9258(20)80460-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
13
|
Affiliation(s)
- C Seeger
- Department of Microbiology, Immunology and Parasitology, New York State College of Veterinary Medicine, Cornell University, Ithaca 14853
| | | | | |
Collapse
|
14
|
Ballester S, Lopez P, Espinosa M, Alonso JC, Lacks SA. Plasmid structural instability associated with pC194 replication functions. J Bacteriol 1989; 171:2271-7. [PMID: 2708307 PMCID: PMC209898 DOI: 10.1128/jb.171.5.2271-2277.1989] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The hybrid plasmid pJS37 is composed of the streptococcal plasmid pLS1, which confers tetracycline resistance, and the staphylococcal plasmid pC194, which confers chloramphenicol resistance. When gram-positive bacteria containing pJS37 were grown in the presence of chloramphenicol, four different deleted derivatives accumulated. The deletions in the plasmid enhanced resistance to chloramphenicol by placing the cat gene of pC194 near promoters of pLS1. All four deletions shared a common endpoint that corresponded to the putative target site for DNA strand nicking by the pC194 replication protein, RepH. At the other, variable endpoint, the DNA sequence was similar to the putative RepH target sequence. Alteration of the RepH protein, by in vitro modification of the gene encoding it, eliminated this class of deletions. By extending a previously proposed model for the generation of a different but related class of deletions (B. Michel and S.D. Ehrlich, EMBO J. 5:3691-3696, 1986), a comprehensive model that could generate both classes of deletions is suggested. It proposes that a nicking-closing activity of the plasmid replication protein at its normal target site and, aberrantly, at sites with similar sequence can generate deletions either proximal or distal to the aberrant site during rolling-circle replication of the plasmid.
Collapse
Affiliation(s)
- S Ballester
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | | | | | | | | |
Collapse
|
15
|
Goetz GS, Hurwitz J. Studies on the role of the phi X174 gene A protein in phi X viral strand synthesis. I. Replication of DNA containing an alteration in position 1 of the 30-nucleotide icosahedral bacteriophage origin. J Biol Chem 1988. [DOI: 10.1016/s0021-9258(18)37610-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
16
|
Goetz GS, Hurwitz J. Studies on the role of the phi X174 gene A protein in phi X174 viral strand synthesis. III. Replication of DNA containing two viral replication origins. J Biol Chem 1988. [DOI: 10.1016/s0021-9258(18)37612-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
|
17
|
Drygin YF, Zuklys KL, Terskich AV, Bogdanov AA. A protein covalently bound to ColE1 DNA. EUROPEAN JOURNAL OF BIOCHEMISTRY 1988; 175:57-63. [PMID: 3042396 DOI: 10.1111/j.1432-1033.1988.tb14166.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
ColE1 DNA was isolated from Escherichia coli as a relaxation complex of supercoiled DNA and proteins. Treatment of the complex with either protein-denaturing agents (SDS, phenol etc.) or proteolytic enzymes converted the supercoiled DNA to an open-circular form (relaxation). The relaxation complex was separately labelled in vivo with [3H]Leu or [14C]Leu, [35S]Met or (32P)phosphate and extensively purified. Complete hydrolysis of the relaxed complex with DNase I and P1 nuclease produced a 36-kDa protein which, we believe, is covalently bound to ColE1 DNA. On the other hand, the relaxed complex was treated with tosylphenylalanylchloromethane-treated-trypsin and the DNA-peptide(s) produced was (were) isolated and digested with the nucleases as above. The resulting nucleotidylpeptide(s) was (were) isolated by DEAE-Sephadex chromatography. The only 5'-dCMP was released from the nucleotidylpeptide(s) by snake venom phosphodiesterase treatment. O-Phosphoserine was found in acid hydrolysates of the DNA-peptide(s). We suggest that in the relaxation event the 36-kDa protein becomes covalently linked to ColE1 DNA via a phosphodiester bond between dC and the serine residue.
Collapse
Affiliation(s)
- Y F Drygin
- A. N. Belozersky Laboratory of Molecular Biology and Bioorganic Chemistry, Moscow State University, U.S.S.R
| | | | | | | |
Collapse
|
18
|
|
19
|
Vartapetian AB, Bogdanov AA. Proteins covalently linked to viral genomes. PROGRESS IN NUCLEIC ACID RESEARCH AND MOLECULAR BIOLOGY 1987; 34:209-51. [PMID: 3326040 DOI: 10.1016/s0079-6603(08)60497-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
|
20
|
Fluit AC, Baas PD, Jansz HS. Termination and reinitiation signals of bacteriophage phi X174 rolling circle DNA replication. Virology 1986; 154:357-68. [PMID: 2945311 DOI: 10.1016/0042-6822(86)90461-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The nucleotide sequence requirements for termination and reinitiation of rolling circle DNA replication within the 30-bp phi X174 origin region were studied. Plasmids were constructed which contained a complete and a partial phi X174 origin region in the same orientation. The partial origin consisted of the first 16, 24, 25, 26, 27, or 28 bp of the origin region. Plasmids harboring a complete origin region are subject to rolling circle DNA replication and packaging of single-stranded plasmid DNA into phage coats in phi X174 or G4 phage infected cells. The plasmids with a complete and partial origin region were tested in these in vivo transduction systems. The results lead to the following conclusions: The phi X174 and G4 in vivo transduction systems are useful in studying termination and reinitiation of rolling circle DNA replication. The first 24 bp of the origin region are sufficient for termination of a round of rolling circle DNA replication coupled to DNA packaging. The first 16 bp, however, are not recognized as a termination signal. Reinitiation of rolling circle DNA replication coupled to DNA packaging on a partial origin region occurs with low frequency.
Collapse
|
21
|
Baas PD. DNA replication of single-stranded Escherichia coli DNA phages. BIOCHIMICA ET BIOPHYSICA ACTA 1985; 825:111-39. [PMID: 3890949 DOI: 10.1016/0167-4781(85)90096-x] [Citation(s) in RCA: 70] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
|
22
|
Fluit AC, Baas PD, Jansz HS. The complete 30-base-pair origin region of bacteriophage phi X174 in a plasmid is both required and sufficient for in vivo rolling-circle DNA replication and packaging. EUROPEAN JOURNAL OF BIOCHEMISTRY 1985; 149:579-84. [PMID: 2988951 DOI: 10.1111/j.1432-1033.1985.tb08964.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The origin of replication of the isometric single-stranded DNA bacteriophages is located in a specific sequence of 30 nucleotides, the origin region, which is highly conserved in these phage genomes. Plasmids harboring this origin region are subject to rolling-circle DNA replication and packaging of single-stranded (ss) plasmid DNA into phage coats in phi X174 or G4-phage-infected cells. This system was used to study the nucleotide sequence requirements for rolling-circle DNA replication and DNA packaging employing plasmids which contain the first 24, 25, 26, 27, 28 and the complete 30-base-pair (bp) origin region of phi X174. No difference in plasmid ss DNA packaging was observed for plasmids carrying only the 30-bp origin region and plasmids carrying the 30-bp origin region plus surrounding sequences (i.e. plasmids carrying the HaeIII restriction fragment Z6B of phi X174 replicative-form DNA). This indicates that all signals for DNA replication and phage morphogenesis are contained in the 30-bp origin region and that no contribution is made by sequences which immediately surround the origin region in the phi X174 genome. The efficiency of packaging of plasmid ssDNA for plasmids containing deletions in the right part of the origin region decreases drastically when compared with the plasmid containing the complete 30-bp origin region (for a plasmid carrying the first 28 bp of the origin region to approximately 5% and 0.5% in the phi X174 and G4 systems respectively). Previous studies [Fluit, A.C., Baas, P.D., van Boom, J.H., Veeneman, G.H. and Jansz, H.S. (1984) Nucleic Acids Res. 12, 6443--6454] have shown that the presence of the first 27 bp of the origin region is necessary as well as sufficient for cleavage of the viral strand in the origin region by phi X174 gene A protein. Moreover, Brown et al. [Brown, D.R., Schmidt-Glenewinkel, T., Reinberg, D. and Hurwitz, J. (1983) J. Biol. Chem. 258, 8402--8412] have shown that omission of the last 2 bp of the origin region does not interfere with phi X174 rolling-circle DNA replication in vitro. Our results therefore suggest that for optimal phage development in vivo, signals in the origin region are utilized which have not yet been noticed by the in vitro systems for phi X174 phage DNA replication and morphogenesis.
Collapse
|
23
|
Sanhueza S, Eisenberg S. Bacteriophage phi X174 A protein cleaves single-stranded DNA and binds to it covalently through a tyrosyl-dAMP phosphodiester bond. J Virol 1985; 53:695-7. [PMID: 3155802 PMCID: PMC254688 DOI: 10.1128/jvi.53.2.695-697.1985] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The phi X174 A protein cleaves single-stranded DNA and binds covalently to the 5'-phosphorylated end. To determine the nature of the covalent linkage and the amino acid involved, we used the A protein to cleave DNA synthesized in vitro with [alpha-32P]dATP to form the complex of A protein covalently linked to single-stranded DNA. The complex was then digested with DNase I, and the 32P-labeled A protein was isolated by electrophoresis on polyacrylamide gels. The isolated complex was treated extensively with trypsin, and the released peptide-oligonucleotide complexes were incubated with formic acid and diphenylamine (Burton reaction). The Burton reaction caused a transfer of the labeled phosphate from dAMP to the peptide. The labeled phosphopeptides were isolated and hydrolyzed, revealing a linkage of the phosphate to a tyrosine. These results indicate that the A protein cleaves single-stranded DNA and binds covalently to the 5'-phosphorylated terminus by a tyrosyl-dAMP phosphodiester bond.
Collapse
|
24
|
Brown DR, Roth MJ, Reinberg D, Hurwitz J. Analysis of bacteriophage phi X174 gene A protein-mediated termination and reinitiation of phi X DNA synthesis. I. Characterization of the termination and reinitiation reactions. J Biol Chem 1984. [DOI: 10.1016/s0021-9258(18)90998-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
25
|
Marians KJ. Enzymology of DNA in replication in prokaryotes. CRC CRITICAL REVIEWS IN BIOCHEMISTRY 1984; 17:153-215. [PMID: 6097404 DOI: 10.3109/10409238409113604] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
This review stresses recent developments in the in vitro study of DNA replication in prokaryotes. New insights into the enzymological mechanisms of initiation and elongation of leading and lagging strand DNA synthesis in ongoing studies are emphasized. Data from newly developed systems, such as those replicating oriC containing DNA or which are dependent on the lambda, O, and P proteins, are presented and the information compared to existing mechanisms. Evidence bearing on the coupling of DNA synthesis on both parental strands through protein-protein interactions and on the turnover of the elongation systems are analyzed. The structure of replication origins, and how their tertiary structure affects recognition and interaction with the various replication proteins is discussed.
Collapse
|