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Li P, Zhang J, Deng Z, Gao F, Ou HY. Identification and characterization of a central replication origin of the mega-plasmid pSCATT of Streptomyces cattleya. Microbiol Res 2022; 257:126975. [DOI: 10.1016/j.micres.2022.126975] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 01/17/2022] [Accepted: 01/20/2022] [Indexed: 11/25/2022]
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2
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Harris L, van Zyl LJ, Kirby-McCullough BM, Damelin LH, Tiemessen CT, Trindade M. Identification and sequence analysis of two novel cryptic plasmids isolated from the vaginal mucosa of South African women. Plasmid 2018; 98:56-62. [PMID: 30240699 DOI: 10.1016/j.plasmid.2018.09.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 09/13/2018] [Accepted: 09/16/2018] [Indexed: 10/28/2022]
Abstract
The vaginal mucosa is dominated by Gram positive, rod shaped lactobacilli which serve as a natural barrier against infection. In both healthy- and bacterial vaginosis (BV)-infected women Lactobacillus crispatus and Lactobacillus jensenii have been found to be the predominant Lactobacillus species. Many studies have been conducted to assess factors influencing lactobacilli dominance in the vaginal microbiome. In the present study two plasmids, pLc4 and pLc17, isolated from vaginal Lactobacillus strains of both healthy and BV-infected women were characterized. The smaller plasmid, pLc4 (4224 bp), was detected in both L. crispatus and L. jensenii strains, while pLc17 was only detected in L. crispatus. Based on its nucleotide sequence pLc4 appears highly novel, with its replication protein having 44% identity to the replication initiation protein of pSMQ173b_03. Phylogenetic analysis with other Rolling Circle Replication plasmids confirmed that pLc4 shows a low degree of similarity to these plasmids. Plasmid pLc17 (16,663 bp) appears to carry both a RCR replicon and a theta replicon, which is rare in naturally occurring plasmids. pLc4 was maintained at a high copy number of 29, while pLc17 appears to be a medium copy number plasmid maintained at 11 copies per chromosome. While sequence analysis is a valuable tool to study cryptic plasmids, further function-based analysis will be required in order to fully elucidate the role of these plasmids within the vaginal milieu.
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Affiliation(s)
- Lyle Harris
- Institute for Microbial Biotechnology and Metagenomics, University of the Western Cape, Cape Town, South Africa
| | - Leonardo J van Zyl
- Institute for Microbial Biotechnology and Metagenomics, University of the Western Cape, Cape Town, South Africa
| | - Bronwyn M Kirby-McCullough
- Institute for Microbial Biotechnology and Metagenomics, University of the Western Cape, Cape Town, South Africa
| | - Leonard H Damelin
- Centre for HIV & STIs, National Institute of Communicable Diseases, Sandringham, Johannesburg, South Africa; Faculty of Health Sciences, University of the Witwatersrand, South Africa
| | - Caroline T Tiemessen
- Centre for HIV & STIs, National Institute of Communicable Diseases, Sandringham, Johannesburg, South Africa; Faculty of Health Sciences, University of the Witwatersrand, South Africa
| | - Marla Trindade
- Institute for Microbial Biotechnology and Metagenomics, University of the Western Cape, Cape Town, South Africa.
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3
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Peng S, Zeng A, Zhong L, Zhang R, Zhou M, Cheng Q, Zhao L, Wang T, Tan H, Qin Z. Three functional replication origins of the linear and artificially circularized plasmid SCP1 of Streptomyces coelicolor. Microbiology (Reading) 2013; 159:2127-2140. [DOI: 10.1099/mic.0.067363-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Affiliation(s)
- Shiyuan Peng
- Key Laboratory of Synthetic Biology, Shanghai Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, PR China
| | - Ana Zeng
- Key Laboratory of Synthetic Biology, Shanghai Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, PR China
| | - Li Zhong
- Key Laboratory of Synthetic Biology, Shanghai Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, PR China
| | - Ran Zhang
- Key Laboratory of Synthetic Biology, Shanghai Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, PR China
| | - Min Zhou
- Key Laboratory of Synthetic Biology, Shanghai Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, PR China
| | - Qiuxiang Cheng
- Key Laboratory of Synthetic Biology, Shanghai Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, PR China
| | - Liqian Zhao
- Key Laboratory of Synthetic Biology, Shanghai Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, PR China
| | - Tao Wang
- Key Laboratory of Synthetic Biology, Shanghai Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, PR China
| | - Huarong Tan
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China
| | - Zhongjun Qin
- Key Laboratory of Synthetic Biology, Shanghai Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, PR China
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4
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Characterization of pMRI 5.2, a rolling-circle-type plasmid from Lactobacillus plantarum BFE 5092 which harbours two different replication initiation genes. Plasmid 2013; 69:160-71. [DOI: 10.1016/j.plasmid.2012.11.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2012] [Revised: 11/28/2012] [Accepted: 11/29/2012] [Indexed: 12/11/2022]
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5
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Development of an efficient in vivo system (Pjunc-TpaseIS1223) for random transposon mutagenesis of Lactobacillus casei. Appl Environ Microbiol 2012; 78:5417-23. [PMID: 22610425 DOI: 10.1128/aem.00531-12] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
The random transposon mutagenesis system P(junc)-TpaseIS(1223) is composed of plasmids pVI129, expressing IS1223 transposase, and pVI110, a suicide transposon plasmid carrying the P(junc) sequence, the substrate of the IS1223 transposase. This system is particularly efficient in Lactobacillus casei, as more than 10,000 stable, random mutants were routinely obtained via electroporation.
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6
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Two internal origins of replication in Streptomyces linear plasmid pFRL1. Appl Environ Microbiol 2010; 76:5676-83. [PMID: 20601502 DOI: 10.1128/aem.02905-09] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Previous reports showed that Streptomyces linear plasmids usually contain one internal replication locus. Here, we identified two new replication loci on pFRL1, one (rep1A-ncs1) next to a telomere and another (rep2A-ncs2) approximately 10 kb from it. The rep1A-ncs1 locus was able to direct replication independently in both linear and circular modes, whereas rep2A-ncs2 required an additional locus, rlrA-rorA, in order to direct propagation in linear mode. Rep1A protein bound to ncs1 in vitro. By quantitative reverse transcription-PCR and Northern hybridization, we showed that transcription of rep1A and rep2A varied during development and that each dominated at different time points. pFRL1-derived linear plasmids were inherited through spores more stably than circular plasmids and were more stable with pSLA2 telomeres than with pFRL1 telomeres in Streptomyces lividans.
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7
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Weihofen WA, Cicek A, Pratto F, Alonso JC, Saenger W. Structures of omega repressors bound to direct and inverted DNA repeats explain modulation of transcription. Nucleic Acids Res 2006; 34:1450-8. [PMID: 16528102 PMCID: PMC1401508 DOI: 10.1093/nar/gkl015] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Repressor omega regulates transcription of genes required for copy number control, accurate segregation and stable maintenance of inc18 plasmids hosted by Gram-positive bacteria. omega belongs to homodimeric ribbon-helix-helix (RHH2) repressors typified by a central, antiparallel beta-sheet for DNA major groove binding. Homodimeric omega2 binds cooperatively to promotors with 7 to 10 consecutive non-palindromic DNA heptad repeats (5'-(A)/(T)ATCAC(A)/(T)-3', symbolized by -->) in palindromic inverted, converging (--><--) or diverging (<---->) orientation and also, unique to omega2 and contrasting other RHH2 repressors, to non-palindromic direct (-->-->) repeats. Here we investigate with crystal structures how omega2 binds specifically to heptads in minimal operators with (-->-->) and (--><--) repeats. Since the pseudo-2-fold axis relating the monomers in omega(2) passes the central C-G base pair of each heptad with approximately 0.3 A downstream offset, the separation between the pseudo-2-fold axes is exactly 7 bp in (-->-->), approximately 0.6 A shorter in (--><--) but would be approximately 0.6 A longer in (<---->). These variations grade interactions between adjacent omega2 and explain modulations in cooperative binding affinity of omega2 to operators with different heptad orientations.
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Affiliation(s)
| | | | - Florencia Pratto
- Departamento de Biotecnología Microbiana, Centro Nacional de BiotecnologíaCSIC, 28049 Madrid, Spain
| | - Juan Carlos Alonso
- Departamento de Biotecnología Microbiana, Centro Nacional de BiotecnologíaCSIC, 28049 Madrid, Spain
| | - Wolfram Saenger
- To whom correspondence should be addressed. Tel: +49 30 838 53412; Fax: +49 30 838 56702;
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8
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Bruand C, Velten M, McGovern S, Marsin S, Sérèna C, Ehrlich SD, Polard P. Functional interplay between the Bacillus subtilis DnaD and DnaB proteins essential for initiation and re-initiation of DNA replication. Mol Microbiol 2005; 55:1138-50. [PMID: 15686560 DOI: 10.1111/j.1365-2958.2004.04451.x] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Initiation and re-initiation of chromosomal DNA replication in bacteria rely on divergent multiprotein assemblies, which direct the functional delivery of the replicative helicase on single-stranded DNA (ssDNA) at specific sites. These two processes are triggered either at the single chromosomal origin oriC or at arrested forks by the conserved DnaA and PriA proteins respectively. In Bacillus subtilis, these two pathways further require the three essential proteins DnaB, DnaD and DnaI, restrictively encoded in Gram positive bacteria of low GC content. We have recently shown that DnaI and DnaB act as a pair of loaders of the DnaC replicative helicase. The role of DnaD appeared more enigmatic. It was previously shown to interact with DnaA and to display weak ssDNA binding activity. Here, we report that purified DnaD can interact physically with PriA and with DnaB. We show that the lethality of the temperature-sensitive dnaD23 mutant can be suppressed by different DnaB point mutants, which were found to be identical to the suppressors of priA null mutants. The DnaD23 protein displays lower ssDNA binding activity than DnaD. Conversely, the DnaB75 protein, the main dnaD23 suppressor, has gained affinity for ssDNA. Finally, we observed that this interplay between DnaD and DnaB is crucial for their concerted interaction with SSB-coated ssDNA, which is the expected substrate for the loading of the replicative helicase in vivo. Altogether, these results highlight the need for both DnaD and DnaB to interact individually and together with ssDNA during the early stages of initiation and re-initiation of chromosomal DNA replication. They also point at a main structural role of DnaD in the multiprotein assemblies built during these two essential processes.
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Affiliation(s)
- Claude Bruand
- Laboratoire de Génétique Microbienne, INRA, Domaine de Vilvert, 78352 Jouy-en-Josas, France
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9
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Davis IJ, Roberts AP, Ready D, Richards H, Wilson M, Mullany P. Linkage of a novel mercury resistance operon with streptomycin resistance on a conjugative plasmid in Enterococcus faecium. Plasmid 2004; 54:26-38. [PMID: 15907536 DOI: 10.1016/j.plasmid.2004.10.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2004] [Revised: 10/15/2004] [Accepted: 10/24/2004] [Indexed: 11/17/2022]
Abstract
It has been shown that the mercury in dental amalgam and other environmental sources can select for mercury resistant bacteria and that this can lead to an increase in resistance to antibiotics. To understand more about this linkage we have investigated the genetic basis for mercury and antibiotic resistance in a variety of oral bacteria. In this study we have cloned and sequenced the mer operon from an Enterococcus faecium strain which was resistant to mercury, tetracycline, and streptomycin. This strain was isolated, in a previous investigation, from a cynomolgus monkey post-installation of amalgam fillings. The mer operon was contained within a putative transposon (Tnmer1) of the ISL3 family. This element was located on a streptomycin resistant plasmid, pPPM1000, which shares homology with pRE25.
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Affiliation(s)
- Ian J Davis
- Division of Microbial Diseases, Eastman Dental Institute, University College London, 256 Gray's Inn Road, London, WC1X 8LD, UK
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10
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Thompson JK, Collins MA. Completed sequence of plasmid pIP501 and origin of spontaneous deletion derivatives. Plasmid 2003; 50:28-35. [PMID: 12826055 DOI: 10.1016/s0147-619x(03)00042-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The sequence of plasmid pIP501 (30,603 bp) was completed using previously published and newly acquired data. The sites at which two spontaneous deletions had occurred were identified. One was between tracts of repeated heptamers and the other between regions of secondary structure associated with plasmid replication. A high level of identity ( >95%) between plasmid pIP501 and part of plasmid pRE25, which had been isolated from Enterococcus faecalis associated with a food source, was confirmed.
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Affiliation(s)
- J K Thompson
- Department of Food Science (Food Microbiology), Department of Agriculture and Rural Development for Northern Ireland, Newforge Lane, Belfast BT9 5PX, Northern Ireland, UK.
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11
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Serror P, Ilami G, Chouayekh H, Ehrlich SD, Maguin E. Transposition in Lactobacillus delbrueckii subsp. bulgaricus: identification of two thermosensitive replicons and two functional insertion sequences. MICROBIOLOGY (READING, ENGLAND) 2003; 149:1503-1511. [PMID: 12777490 DOI: 10.1099/mic.0.25827-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
In this report, it is shown that the rolling circle replicon pG(+)host and the theta replicon pIP501 are thermosensitive in Lactobacillus delbrueckii subsp. bulgaricus (Lactobacillus bulgaricus). Using a pIP501 derivative as a delivery vector for six insertion sequences originating from lactic acid bacteria, it is shown that IS1223 and IS1201 transpose in L. bulgaricus.
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Affiliation(s)
- Pascale Serror
- Unité Recherche Laitière et Génétique Appliquée, INRA, Domaine de Vilvert, 78352 Jouy-en-Josas Cedex, France
| | - Golnar Ilami
- Génétique Microbienne, INRA, Domaine de Vilvert, 78352 Jouy-en-Josas Cedex, France
| | - Hichem Chouayekh
- Génétique Microbienne, INRA, Domaine de Vilvert, 78352 Jouy-en-Josas Cedex, France
| | - S Dusko Ehrlich
- Génétique Microbienne, INRA, Domaine de Vilvert, 78352 Jouy-en-Josas Cedex, France
| | - Emmanuelle Maguin
- Génétique Microbienne, INRA, Domaine de Vilvert, 78352 Jouy-en-Josas Cedex, France
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12
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Polard P, Marsin S, McGovern S, Velten M, Wigley DB, Ehrlich SD, Bruand C. Restart of DNA replication in Gram-positive bacteria: functional characterisation of the Bacillus subtilis PriA initiator. Nucleic Acids Res 2002; 30:1593-605. [PMID: 11917020 PMCID: PMC101839 DOI: 10.1093/nar/30.7.1593] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The PriA protein was identified in Escherichia coli as a factor involved in the replication of extrachromosomal elements such as bacteriophage phiX174 and plasmid pBR322. Recent data show that PriA plays an important role in chromosomal replication, by promoting reassembly of the replication machinery during reinitiation of inactivated forks. A gene encoding a product 32% identical to the E.coli PriA protein has been identified in Bacillus subtilis. To characterise this protein, designated PriA(Bs), we constructed priA(Bs) mutants. These mutants are poorly viable, filamentous and sensitive to rich medium and UV irradiation. Replication of pAMbeta1-type plasmids, which is initiated through the formation of a D-loop structure, and the activity of the primosome assembly site ssiA of plasmid pAMbeta1 are strongly affected in the mutants. The purified PriA(Bs) protein binds preferentially to the active strand of ssiA, even in the presence of B.subtilis SSB protein (SSB(Bs)). PriA(Bs) also binds stably and specifically to an artificial D-loop structure in vitro. These data show that PriA(Bs) recognises two specific substrates, ssiA and D-loops, and suggest that it triggers primosome assembly on them. PriA(Bs) also displays a single-stranded DNA-dependent ATPase activity, which is reduced in the presence of SSB(Bs), unless the ssiA sequence is present on the ssDNA substrate. Finally, PriA(Bs) is shown to be an active helicase. Altogether, these results demonstrate a clear functional identity between PriA(Ec) and PriA(Bs). However, PriA(Bs) does not complement an E.coli priA null mutant strain. This host specificity may be due to the divergence between the proteins composing the E.coli and B.subtilis PriA-dependent primosomes.
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Affiliation(s)
- Patrice Polard
- Laboratoire de Génétique Microbienne, INRA, Domaine de Vilvert, 78352 Jouy en Josas cedex, France
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13
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Thompson JK, McConville KJ, Nicholson C, Collins MA. DNA cloning in Lactobacillus helveticus by the exconjugation of recombinant mob-containing plasmid constructs from strains of transformable lactic acid bacteria. Plasmid 2001; 46:188-201. [PMID: 11735368 DOI: 10.1006/plas.2001.1540] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A system developed for the genetic transfer of plasmids between strains of nontransformable bacteria (P. Langella, Y. le Loir, S. D. Ehrlich and A. Gruss, 1993, J. Bacteriol., 175, 5806-5813) by the specific inclusion of a mobilization (mob) region into a nonconjugative shuttle vector was used successfully to deliver the genetic determinants for beta-glucanase, beta-glucuronidase, and green fluorescent protein to Lactobacillus helveticus. Expression of two of the genes could be detected in the new host. Data suggested that resolution of cointegrates into components could release the original recombinant plasmid or generate a cointegrate deletion. All the recombinant plasmids were segregationally unstable in Lb. helveticus and there was some evidence for structural instability. Intrinsic instability in the mob-containing vector was reduced by replacing the duplicated pBluescript polylinker with that from pUC19. Sites at which cointegrate formation could occur were localized at two distinct tracts close to the D-loop that forms at the primosome during plasmid replication.
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Affiliation(s)
- J K Thompson
- Department of Food Science (Food Microbiology), Rural Development for Northern Ireland, UK.
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14
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Schwarz FV, Perreten V, Teuber M. Sequence of the 50-kb conjugative multiresistance plasmid pRE25 from Enterococcus faecalis RE25. Plasmid 2001; 46:170-87. [PMID: 11735367 DOI: 10.1006/plas.2001.1544] [Citation(s) in RCA: 124] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The complete 50,237-bp DNA sequence of the conjugative and mobilizing multiresistance plasmid pRE25 from Enterococcus faecalis RE25 was determined. The plasmid had 58 putative open reading frames, 5 of which encode resistance to 12 antimicrobials. Chloramphenicol acetyltransferase and the 23S RNA methylase are identical to gene products of the broad-host-range plasmid pIP501 from Streptococcus agalactiae. In addition, a 30.5-kb segment is almost identical to pIP501. Genes encoding an aminoglycoside 6-adenylyltransferase, a streptothricin acetyltransferase, and an aminoglycoside phosphotransferase are arranged in tandem on a 7.4-kb fragment as previously reported in Tn5405 from Staphylococcus aureus and in pJH1 from E. faecalis. One interrupted and five complete IS elements as well as three replication genes were also identified. pRE25 was transferred by conjugation to E. faecalis, Listeria innocua, and Lactococcus lactis by means of a transfer region that appears similar to that of pIP501. It is concluded that pRE25 may contribute to the further spread of antibiotic-resistant microorganisms via food into the human community.
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Affiliation(s)
- F V Schwarz
- Laboratory for Food Microbiology, Swiss Federal Institute of Technology of Zurich, Zurich, CH-8092, Switzerland
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15
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Bruand C, Farache M, McGovern S, Ehrlich SD, Polard P. DnaB, DnaD and DnaI proteins are components of the Bacillus subtilis replication restart primosome. Mol Microbiol 2001; 42:245-55. [PMID: 11679082 DOI: 10.1046/j.1365-2958.2001.02631.x] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Phenotypes of Bacillus subtilis priA mutants suggest that they are deficient in the restart of stalled chromosomal replication forks. The presumed activity of PriA in the restart process is to promote the assembly of a multiprotein complex, the primosome, which functions to recruit the replication fork helicase onto the DNA. We have proposed previously that three proteins involved in the initiation of replication at oriC in B. subtilis, DnaB, DnaD and DnaI, are components of the PriA primosome in this bacterium. However, the involvement of these proteins in replication restart has not yet been studied. Here, we describe dnaB mutations that suppress the phenotypes of B. subtilis priA mutants. In a representative mutant, the DnaC helicase is loaded onto single-stranded DNA in a PriA-independent, DnaD- and DnaI-dependent manner. These observations confirm that DnaB, DnaD and DnaI are primosomal proteins in B. subtilis. Moreover, their involvement in the suppression of priA phenotypes shows that they participate in replication fork restart in B. subtilis.
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Affiliation(s)
- C Bruand
- Laboratoire de Génétique Microbienne, INRA, Domaine de Vilvert, 78352 Jouy-en-Josas cedex, France.
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16
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de la Hoz AB, Ayora S, Sitkiewicz I, Fernández S, Pankiewicz R, Alonso JC, Ceglowski P. Plasmid copy-number control and better-than-random segregation genes of pSM19035 share a common regulator. Proc Natl Acad Sci U S A 2000; 97:728-33. [PMID: 10639147 PMCID: PMC15398 DOI: 10.1073/pnas.97.2.728] [Citation(s) in RCA: 113] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Transcription initiation of the copy-number control and better-than-random segregation genes of the broad-host-range and low-copy-number plasmid pSM19035 are subjected to repression by the autoregulated pSM19035-encoded omega product in Bacillus subtilis cells. The promoters of the copS (Pcop1 and Pcop2), delta (Pdelta), and omega (Pomega) genes have been mapped. These promoters are embedded in a set of either seven copies of a 7-bp direct repeat or in a block consisting of two 7-bp direct repeats and one 7-bp inverted repeat; the blocks are present either two or three times. The cooperative binding of omega protein to the repeats on the Pcop1, Pcop2, Pdelta, and Pomega promoters represses transcription initiation by a mechanism that does not exclude sigma(A)RNAP from the promoters. These results indicate that omega protein regulates plasmid maintenance by controlling the copy number on the one hand and by regulating the amount of proteins required for better-than-random segregation on the other hand.
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Affiliation(s)
- A B de la Hoz
- Department of Microbial Biotechnology, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, 28049 Madrid, Spain
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17
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Pujol CJ, Kado CI. Characterization of pUCD5000 involved in pink disease color formation by Pantoea citrea. Plasmid 1998; 40:169-73. [PMID: 9735319 DOI: 10.1006/plas.1998.1355] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Pantoea citrea, the causal agent of pink disease of pineapple, harbors a cryptic plasmid of 5229 bp. designated pUCD5000. On the basis of nucleotide and amino acid sequence analyses, pUCD5000 contains both replication and mobilization loci (bom and mobCABD) that are similar to those in plasmids pSW100 and pSW200 in Pantoea stewartii and pEC3 in Erwinia carotovora subsp. carotovora. The survival of P. citrea on pineapple does not depend on pUCD5000. However, full pink coloration development, which is characteristic of the pink disease, appears to require this plasmid.
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Affiliation(s)
- C J Pujol
- Department of Plant Pathology, University of California, Davis 95616, USA
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