1
|
Deciphering the Regulatory Circuits of RA3 Replication Module - Mechanisms of the Copy Number Control. Int J Mol Sci 2022; 23:ijms23179964. [PMID: 36077372 PMCID: PMC9455977 DOI: 10.3390/ijms23179964] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2022] [Revised: 08/26/2022] [Accepted: 08/26/2022] [Indexed: 12/03/2022] Open
Abstract
The RA3 plasmid, the archetype of IncU incompatibility group, represents a mosaic-modular genome of 45.9 kb. The replication module encompasses repA and repB (initiator) surrounded by two long repetitive sequences DR1 and DR2 of unknown function. Here, we mapped the origin of replication oriV to the 3′ end of repB and showed that oriV was activated by the transcription coming from orf02revp in the adjacent stability module. Using various in vivo and in vitro methods we demonstrated that the repB expression proceeded either from repBp located in the intergenic repA-repB region or from the upstream strong repAp that was autoregulated by RepA. Additionally, the repBp activity was modulated by the transcription from the overlapping, divergently oriented repXp. Both repXmRNA (antisense for repAmRNA) and its small polypeptide product, RepX, were strong incompatibility determinants. Hence, we showed that the sophisticated RA3 copy number control combined the multivalent regulation of repB expression, RepB titration by DR1, and transcriptional activation of oriV, dependent on the RA3 global regulatory network. Similarly organized replicons have been found in diverse bacterial species confirming the significance of these mechanisms in establishing the IncU plasmids in a broad spectrum of hosts.
Collapse
|
2
|
Mitura M, Lewicka E, Godziszewska J, Adamczyk M, Jagura-Burdzy G. Alpha-Helical Protein KfrC Acts as a Switch between the Lateral and Vertical Modes of Dissemination of Broad-Host-Range RA3 Plasmid from IncU (IncP-6) Incompatibility Group. Int J Mol Sci 2021; 22:4880. [PMID: 34063039 PMCID: PMC8124265 DOI: 10.3390/ijms22094880] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 04/27/2021] [Accepted: 05/03/2021] [Indexed: 12/24/2022] Open
Abstract
KfrC proteins are encoded by the conjugative broad-host-range plasmids that also encode alpha-helical filament-forming KfrA proteins as exemplified by the RA3 plasmid from the IncU incompatibility group. The RA3 variants impaired in kfrA, kfrC, or both affected the host's growth and demonstrated the altered stability in a species-specific manner. In a search for partners of the alpha-helical KfrC protein, the host's membrane proteins and four RA3-encoded proteins were found, including the filamentous KfrA protein, segrosome protein KorB, and the T4SS proteins, the coupling protein VirD4 and ATPase VirB4. The C-terminal, 112-residue dimerization domain of KfrC was involved in the interactions with KorB, the master player of the active partition, and VirD4, a key component of the conjugative transfer process. In Pseudomonas putida, but not in Escherichia coli, the lack of KfrC decreased the stability but improved the transfer ability. We showed that KfrC and KfrA were involved in the plasmid maintenance and conjugative transfer and that KfrC may play a species-dependent role of a switch between vertical and horizontal modes of RA3 spreading.
Collapse
Affiliation(s)
- Monika Mitura
- Laboratory of DNA Segregation and Cell Cycle of Proteobacteria, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland; (M.M.); (E.L.); (J.G.)
| | - Ewa Lewicka
- Laboratory of DNA Segregation and Cell Cycle of Proteobacteria, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland; (M.M.); (E.L.); (J.G.)
| | - Jolanta Godziszewska
- Laboratory of DNA Segregation and Cell Cycle of Proteobacteria, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland; (M.M.); (E.L.); (J.G.)
| | - Malgorzata Adamczyk
- Faculty of Chemistry, Chair of Drug and Cosmetics Biotechnology, Warsaw University of Technology, 00-664 Warsaw, Poland;
| | - Grazyna Jagura-Burdzy
- Laboratory of DNA Segregation and Cell Cycle of Proteobacteria, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland; (M.M.); (E.L.); (J.G.)
| |
Collapse
|
3
|
Adamczyk M, Lewicka E, Szatkowska R, Nieznanska H, Ludwiczak J, Jasiński M, Dunin-Horkawicz S, Sitkiewicz E, Swiderska B, Goch G, Jagura-Burdzy G. Revealing biophysical properties of KfrA-type proteins as a novel class of cytoskeletal, coiled-coil plasmid-encoded proteins. BMC Microbiol 2021; 21:32. [PMID: 33482722 PMCID: PMC7821693 DOI: 10.1186/s12866-020-02079-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 12/20/2020] [Indexed: 01/22/2023] Open
Abstract
Background DNA binding KfrA-type proteins of broad-host-range bacterial plasmids belonging to IncP-1 and IncU incompatibility groups are characterized by globular N-terminal head domains and long alpha-helical coiled-coil tails. They have been shown to act as transcriptional auto-regulators. Results This study was focused on two members of the growing family of KfrA-type proteins encoded by the broad-host-range plasmids, R751 of IncP-1β and RA3 of IncU groups. Comparative in vitro and in silico studies on KfrAR751 and KfrARA3 confirmed their similar biophysical properties despite low conservation of the amino acid sequences. They form a wide range of oligomeric forms in vitro and, in the presence of their cognate DNA binding sites, they polymerize into the higher order filaments visualized as “threads” by negative staining electron microscopy. The studies revealed also temperature-dependent changes in the coiled-coil segment of KfrA proteins that is involved in the stabilization of dimers required for DNA interactions. Conclusion KfrAR751 and KfrARA3 are structural homologues. We postulate that KfrA type proteins have moonlighting activity. They not only act as transcriptional auto-regulators but form cytoskeletal structures, which might facilitate plasmid DNA delivery and positioning in the cells before cell division, involving thermal energy. Supplementary Information The online version contains supplementary material available at 10.1186/s12866-020-02079-w.
Collapse
Affiliation(s)
- M Adamczyk
- Warsaw University of Technology, Faculty of Chemistry, Chair of Drug and Cosmetics Biotechnology, Noakowskiego 3, 00-664, Warsaw, Poland.
| | - E Lewicka
- Department of Microbial Biochemistry, Institute of Biochemistry and Biophysics PAS, Pawinskiego 5a, 02-106, Warsaw, Poland
| | - R Szatkowska
- Warsaw University of Technology, Faculty of Chemistry, Chair of Drug and Cosmetics Biotechnology, Noakowskiego 3, 00-664, Warsaw, Poland
| | - H Nieznanska
- Nencki Institute of Experimental Biology PAS, Laboratory of Electron Microscopy, Pasteura 3, 02-093, Warsaw, Poland
| | - J Ludwiczak
- University of Warsaw, Centre of New Technologies, Laboratory of Structural Bioinformatics, 02-097, Warsaw, Poland.,Nencki Institute of Experimental Biology, Laboratory of Bioinformatics, Pasteura 3, 02-093, Warsaw, Poland
| | - M Jasiński
- University of Warsaw, Centre of New Technologies, Laboratory of Structural Bioinformatics, 02-097, Warsaw, Poland
| | - S Dunin-Horkawicz
- University of Warsaw, Centre of New Technologies, Laboratory of Structural Bioinformatics, 02-097, Warsaw, Poland
| | - E Sitkiewicz
- Mass Spectrometry Laboratory, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5a, 02-106, Warsaw, Poland
| | - B Swiderska
- Mass Spectrometry Laboratory, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5a, 02-106, Warsaw, Poland
| | - G Goch
- Department of Microbial Biochemistry, Institute of Biochemistry and Biophysics PAS, Pawinskiego 5a, 02-106, Warsaw, Poland
| | - G Jagura-Burdzy
- Department of Microbial Biochemistry, Institute of Biochemistry and Biophysics PAS, Pawinskiego 5a, 02-106, Warsaw, Poland
| |
Collapse
|
4
|
Lewicka E, Mitura M, Steczkiewicz K, Kieracinska J, Skrzynska K, Adamczyk M, Jagura-Burdzy G. Unique Properties of the Alpha-Helical DNA-Binding Protein KfrA Encoded by the IncU Incompatibility Group Plasmid RA3 and Its Host-Dependent Role in Plasmid Maintenance. Appl Environ Microbiol 2021; 87:e01771-20. [PMID: 33097508 PMCID: PMC7783346 DOI: 10.1128/aem.01771-20] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 10/18/2020] [Indexed: 01/15/2023] Open
Abstract
KfrA, encoded on the broad-host-range RA3 plasmid, is an alpha-helical DNA-binding protein that acts as a transcriptional autoregulator. The KfrARA3 operator site overlaps the kfrA promoter and is composed of five 9-bp direct repeats (DRs). Here, the biological properties of KfrA were studied using both in vivo and in vitro approaches. Localization of the DNA-binding helix-turn-helix motif (HTH) was mapped to the N29-R52 region by protein structure modeling and confirmed by alanine scanning. KfrA repressor ability depended on the number and orientation of DRs in the operator, as well as the ability of the protein to oligomerize. The long alpha-helical tail from residues 54 to 355 was shown to be involved in self-interactions, whereas the region from residue 54 to 177 was involved in heterodimerization with KfrC, another RA3-encoded alpha-helical protein. KfrA also interacted with the segrosome proteins IncC (ParA) and KorB (ParB), representatives of the class Ia active partition systems. Deletion of the kfr genes from the RA3 stability module decreased the plasmid retention in diverse hosts in a species-dependent manner. The specific interactions of KfrA with DNA are essential not only for the transcriptional regulatory function but also for the accessory role of KfrA in stable plasmid maintenance.IMPORTANCE Alpha-helical coiled-coil KfrA-type proteins are encoded by various broad-host-range low-copy-number conjugative plasmids. The DNA-binding protein KfrA encoded on the RA3 plasmid, a member of the IncU incompatibility group, oligomerizes, forms a complex with another plasmid-encoded, alpha-helical protein, KfrC, and interacts with the segrosome proteins IncC and KorB. The unique mode of KfrA dimer binding to the repetitive operator is required for a KfrA role in the stable maintenance of RA3 plasmid in distinct hosts.
Collapse
Affiliation(s)
- Ewa Lewicka
- Institute of Biochemistry and Biophysics, Department of Microbial Biochemistry, PAS, Warsaw, Poland
| | - Monika Mitura
- Institute of Biochemistry and Biophysics, Department of Microbial Biochemistry, PAS, Warsaw, Poland
| | - Kamil Steczkiewicz
- Institute of Biochemistry and Biophysics, Department of Bioinformatics, PAS, Warsaw, Poland
| | - Justyna Kieracinska
- Institute of Biochemistry and Biophysics, Department of Microbial Biochemistry, PAS, Warsaw, Poland
- Warsaw University of Technology, Faculty of Chemistry, Chair of Drug and Cosmetics Biotechnology, Warsaw, Poland
| | - Kamila Skrzynska
- Warsaw University of Technology, Faculty of Chemistry, Chair of Drug and Cosmetics Biotechnology, Warsaw, Poland
| | - Malgorzata Adamczyk
- Warsaw University of Technology, Faculty of Chemistry, Chair of Drug and Cosmetics Biotechnology, Warsaw, Poland
| | - Grazyna Jagura-Burdzy
- Institute of Biochemistry and Biophysics, Department of Microbial Biochemistry, PAS, Warsaw, Poland
| |
Collapse
|
5
|
Lewicka E, Dolowy P, Godziszewska J, Litwin E, Ludwiczak M, Jagura-Burdzy G. Transcriptional Organization of the Stability Module of Broad-Host-Range Plasmid RA3, from the IncU Group. Appl Environ Microbiol 2020; 86:e00847-20. [PMID: 32532870 PMCID: PMC7414963 DOI: 10.1128/aem.00847-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 06/06/2020] [Indexed: 02/06/2023] Open
Abstract
The broad-host-range (BHR) conjugative plasmids have developed diverse adaptive mechanisms defining the range of their promiscuity. The BHR conjugative RA3 plasmid, the archetype of the IncU group, can transfer between, replicate in, and be maintained in representatives of Alpha-, Beta-, and Gammaproteobacteria Its stability module encompasses ten open reading frames (ORFs) apparently organized into five operons, all transcribed in the same direction from several strong promoters that are tightly regulated either by autorepressors or by global plasmid-encoded regulators. In this paper, we demonstrate that owing to an efficient RNA polymerase (RNAP) read-through, the transcription from the first promoter, orf02p, may continue through the whole module. Moreover, an analysis of mRNA produced from the wild-type (WT) stability module and its deletion variants deprived of particular internal transcription initiation sites reveals that in fact each operon may be transcribed from any upstream promoter, giving rise to multicistronic transcripts of variable length and creating an additional level of gene expression control by transcript dosage adjustment. The gene expression patterns differ among various hosts, indicating that promoter recognition, regulation, and the RNAP read-through mechanisms are modulated in a species-specific manner.IMPORTANCE The efficiently disseminating conjugative or mobilizable BHR plasmids play key roles in the horizontal spread of genetic information between closely related and phylogenetically distant species, which can be harmful from the medical, veterinary, or industrial point of view. Understanding the mechanisms determining the plasmid's ability to function in diverse hosts is essential to help limit the spread of undesirable plasmid-encoded traits, e.g., antibiotic resistance. The range of a plasmid's promiscuity depends on the adaptations of its transfer, replication, and stability functions to the various hosts. IncU plasmids, with the archetype plasmid RA3, are considered to constitute a reservoir of antibiotic resistance genes in aquatic environments; however, the molecular mechanisms determining their adaptability to a broad range of hosts are rather poorly characterized. Here, we present the transcriptional organization of the stability module and show that the gene transcript dosage effect is an important determinant of the stable maintenance of RA3 in different hosts.
Collapse
Affiliation(s)
- Ewa Lewicka
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Patrycja Dolowy
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Jolanta Godziszewska
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Emilia Litwin
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Marta Ludwiczak
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Grazyna Jagura-Burdzy
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| |
Collapse
|
6
|
Dang B, Xu Y, Mao D, Luo Y. Complete nucleotide sequence of plasmid pNA6 reveals the high plasticity of IncU family plasmids. Gene 2016; 591:74-79. [PMID: 27374151 DOI: 10.1016/j.gene.2016.06.060] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Revised: 06/21/2016] [Accepted: 06/29/2016] [Indexed: 12/27/2022]
Abstract
Antibiotic resistance is a serious problem in health care and is of widespread public concern. Conjugative plasmids are the most important vectors in the dissemination of antibiotic resistance genes. In this study, we determined the complete sequence of plasmid pNA6, a plasmid which was isolated from the sediments of Haihe River. This plasmid confers reduced susceptibility to ampicillin, erythromycin and sulfamethoxazole. The complete sequence of plasmid pNA6 was 52,210bp in length with an average G+C content of 52.70%. Plasmid pNA6 belongs to the IncU group by sequence queries against the GenBank database. This plasmid has a typical IncU backbone and shows the highest similarities with plasmid RA3 and plasmid pFBAOT6. Plasmid pNA6 carries a class 1 integron consisting of aacA4, ereA and dfrA1 genes. Moreover, plasmid pNA6 also harbors a blaTEM-1-containing complex structure which inserted into the replication region and maintenance region. This insertion site has never been found on other IncU plasmids. The sequencing of plasmid pNA6 will add new sequence information to IncU family plasmids and enhance our understanding of the plasticity of IncU family plasmids.
Collapse
Affiliation(s)
- Bingjun Dang
- School of Environmental Science and Engineering, Tianjin University, Tianjin, China; Ministry of Education Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin, China
| | - Yan Xu
- School of Environmental Science and Engineering, Tianjin University, Tianjin, China; Ministry of Education Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin, China
| | - Daqing Mao
- School of Environmental Science and Engineering, Tianjin University, Tianjin, China.
| | - Yi Luo
- Ministry of Education Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin, China.
| |
Collapse
|
7
|
Godziszewska J, Moncalián G, Cabezas M, Bartosik AA, de la Cruz F, Jagura-Burdzy G. Concerted action of NIC relaxase and auxiliary protein MobC in RA3 plasmid conjugation. Mol Microbiol 2016; 101:439-56. [PMID: 27101775 DOI: 10.1111/mmi.13401] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/19/2016] [Indexed: 11/29/2022]
Abstract
Conjugative transfer of the broad-host-range RA3 plasmid, the archetype of the IncU group, relies on the relaxase NIC that belongs to the as yet uncharacterized MOBP4 subfamily. NIC contains the signature motifs of HUH relaxases involved in Tyr nucleophilic attack. However, it differs in the residue involved in His activation for cation coordination and was shown here to have altered divalent cation requirements. NIC is encoded in the mobC-nic operon preceded directly by oriT, where mobC encodes an auxiliary transfer protein with a dual function: autorepressor and stimulator of conjugative transfer. Here an interplay between MobC and NIC was demonstrated. MobC is required for efficient NIC cleavage of oriT in supercoiled DNA whereas NIC assists MobC in repression of the mobC-nic operon. A 7-bp arm of IR3 (IR3a) was identified as the binding site for NIC and the crucial nucleotides in IR3a for NIC recognition were defined. Fully active oriTRA3 was delineated to a 47-bp DNA segment encompassing a conserved cleavage site sequence, the NIC binding site IR3a and the MobC binding site OM . This highly efficient RA3 conjugative system with defined requirements for minimal oriT could find ample applications in biotechnology and computational biology where simple conjugative systems are needed.
Collapse
Affiliation(s)
- Jolanta Godziszewska
- Institute of Biochemistry and Biophysics PAS, Department of Microbial Biochemistry, 02-106 Warsaw, Poland.,Warsaw University of Life Sciences (WULS-SGGW), Faculty of Human Nutrition and Consumer Sciences, Laboratory of Food Chemistry, 02-776, Warsaw, Poland
| | - Gabriel Moncalián
- Departamento de Biología Molecular and Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), Universidad de Cantabria-CSIC, C/Albert Einstein 22, 39011, Santander, Spain
| | - Matilde Cabezas
- Departamento de Biología Molecular and Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), Universidad de Cantabria-CSIC, C/Albert Einstein 22, 39011, Santander, Spain
| | - Aneta A Bartosik
- Institute of Biochemistry and Biophysics PAS, Department of Microbial Biochemistry, 02-106 Warsaw, Poland
| | - Fernando de la Cruz
- Departamento de Biología Molecular and Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), Universidad de Cantabria-CSIC, C/Albert Einstein 22, 39011, Santander, Spain
| | - Grazyna Jagura-Burdzy
- Institute of Biochemistry and Biophysics PAS, Department of Microbial Biochemistry, 02-106 Warsaw, Poland
| |
Collapse
|
8
|
Dmowski M, Kern-Zdanowicz I. Omega (ParB) binding sites together with the RNA polymerase-recognized sequence are essential for centromeric functions of the Pωregion in the partition system of pSM19035. MICROBIOLOGY-SGM 2016; 162:1114-1124. [PMID: 27177883 DOI: 10.1099/mic.0.000308] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Partition systems contribute to stable plasmid inheritance in bacteria through the active separation of DNA molecules to daughter cells, and the centromeric sequence located either upstream or downstream of canonical partition operons plays an important role in this process. A specific DNA-binding protein binds to this sequence and interacts with the motor NTPase protein to form a nucleoprotein complex. The inc18-family plasmid pSM19035 is partitioned by products of δ and ω genes, with δ encoding a Walker-type ATPase and ω encoding a DNA-binding protein. As the two genes are transcribed separately, this system differs from others in its organization; nonetheless, expression of these genes is regulated by Omega, which also regulates the copy number of the plasmid (by controlling copS gene expression). Protein Omega specifically recognizes WATCACW heptad repeats. In this study, we constructed a synthetic δω operon to enable an analysis of the centromeric functions of Omega-binding sites Pδ, Pω and PcopS, discrete from their promoter functions. Our results show that these three regions do not support plasmid stabilization equally. We demonstrate that the Pω site alone can simultaneously drive the expression of partition genes from the synthetic δω operon and act as a unique centromeric sequence to promote the most efficient plasmid partitioning. Moreover, Pω can support the centromeric function in concert with the synthetic δω operon expressed from a heterologous promoter demonstrating that Pω is the main centromeric sequence of the δ-ω partition system. Additionally, the RNA polymerase-recognized sequence in Pω is essential for its centromeric function.
Collapse
Affiliation(s)
- Michał Dmowski
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5a, 02-106 Warsaw, Poland
| | - Izabela Kern-Zdanowicz
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5a, 02-106 Warsaw, Poland
| |
Collapse
|
9
|
Bartosik AA, Glabski K, Kulinska A, Lewicka E, Godziszewska J, Markowska A, Jagura-Burdzy G. Convenient broad-host-range unstable vectors for studying stabilization cassettes in diverse bacteria. BMC Microbiol 2016; 16:59. [PMID: 27044351 PMCID: PMC4820964 DOI: 10.1186/s12866-016-0674-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Accepted: 03/17/2016] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND Low-copy-number vectors of potential wide application in biotechnology need to encode stabilization modules ensuring their stable inheritance. The efficiency of stabilization may vary depending on the plasmid host so a thorough analysis of stabilization functions is required before use. RESULTS To facilitate such analysis highly unstable, mobilizable, broad-host-range (BHR) vectors based on RK2 replicon were constructed. The vectors are suitable for testing of various stabilization functions, including plasmid and chromosomal partitioning cassettes encoding ParB homologues capable of spreading on DNA. The xylE or lacZ reporter systems facilitate easy monitoring of plasmid segregation. CONCLUSION The range of BHR vectors with different reporter cassettes and alternative mobilization systems expands their application in diverse bacterial species.
Collapse
Affiliation(s)
- Aneta A. Bartosik
- />Department of Microbial Biochemistry, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5A, 02-106 Warsaw, Poland
| | - Krzysztof Glabski
- />Department of Microbial Biochemistry, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5A, 02-106 Warsaw, Poland
| | - Anna Kulinska
- />Department of Microbial Biochemistry, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5A, 02-106 Warsaw, Poland
- />Present address: Faculty of Chemistry, Institute of Biotechnology, Warsaw University of Technology, Warsaw, Poland
| | - Ewa Lewicka
- />Department of Microbial Biochemistry, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5A, 02-106 Warsaw, Poland
| | - Jolanta Godziszewska
- />Department of Microbial Biochemistry, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5A, 02-106 Warsaw, Poland
- />Present address: Faculty of Human Nutrition and Consumer Sciences, Laboratory of Food Chemistry, Warsaw University of Life Sciences, Warsaw, Poland
| | - Aleksandra Markowska
- />Department of Microbial Biochemistry, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5A, 02-106 Warsaw, Poland
- />Present address: Pulawska 255A/4, 02-740 Warsaw, Poland
| | - Grazyna Jagura-Burdzy
- />Department of Microbial Biochemistry, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5A, 02-106 Warsaw, Poland
| |
Collapse
|
10
|
Global Transcriptional Regulation of Backbone Genes in Broad-Host-Range Plasmid RA3 from the IncU Group Involves Segregation Protein KorB (ParB Family). Appl Environ Microbiol 2016; 82:2320-2335. [PMID: 26850301 DOI: 10.1128/aem.03541-15] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 01/31/2016] [Indexed: 01/04/2023] Open
Abstract
The KorB protein of the broad-host-range conjugative plasmid RA3 from the IncU group belongs to the ParB family of plasmid and chromosomal segregation proteins. As a partitioning DNA-binding factor, KorB specifically recognizes a 16-bp palindrome which is an essential motif in the centromere-like sequence parSRA3, forms a segrosome, and together with its partner IncC (ParA family) participates in active DNA segregation ensuring stable plasmid maintenance. Here we show that by binding to this palindromic sequence, KorB also acts as a repressor for the adjacent mobC promoter driving expression of the mobC-nicoperon, which is involved in DNA processing during conjugation. Three other promoters, one buried in the conjugative transfer module and two divergent promoters located at the border between the replication and stability regions, are regulated by KorB binding to additional KorB operators (OBs). KorB acts as a repressor at a distance, binding to OBs separated from their cognate promoters by between 46 and 1,317 nucleotides. This repressor activity is facilitated by KorB spreading along DNA, since a polymerization-deficient KorB variant with its dimerization and DNA-binding abilities intact is inactive in transcriptional repression. KorB may act as a global regulator of RA3 plasmid functions in Escherichia coli, since its overexpression in transnegatively interferes with mini-RA3 replication and stable maintenance of RA3.
Collapse
|
11
|
Ghosh S, LaPara TM, Sadowsky MJ. Transformation of tetracycline by TetX and its subsequent degradation in a heterologous host. FEMS Microbiol Ecol 2015; 91:fiv059. [DOI: 10.1093/femsec/fiv059] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/23/2015] [Indexed: 01/15/2023] Open
|
12
|
Godziszewska J, Kulińska A, Jagura-Burdzy G. MobC of conjugative RA3 plasmid from IncU group autoregulates the expression of bicistronic mobC-nic operon and stimulates conjugative transfer. BMC Microbiol 2014; 14:235. [PMID: 25187417 PMCID: PMC4175270 DOI: 10.1186/s12866-014-0235-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Accepted: 08/19/2014] [Indexed: 11/28/2022] Open
Abstract
Background The IncU conjugative transfer module represents highly efficient promiscuous system widespread among conjugative plasmids of different incompatibility groups. Despite its frequent occurrence the mechanisms of relaxosome formation/action are far from understood. Here we analyzed the putative transfer auxiliary protein MobC of the conjugative plasmid RA3 from the IncU incompatibility group. Results MobC is a protein of 176 amino acids encoded in the bicistronic operon mobC-nic adjacent to oriT. MobC is homologous to prokaryotic transcription factors of the ribbon-helix-helix (RHH) superfamily. Conserved LxxugxNlNQiaxxLn motif clusters MobC with the clade of conjugative transfer auxilliary proteins of MobP relaxases. MobC forms dimers in solution and autoregulates the expression of mobCp by binding to an imperfect palindromic sequence (OM) located between putative -35 and -10 motifs of the promoter. Medium-copy number test plasmid containing the oriT-mobCp region is mobilized with a high frequency by the RA3 conjugative system. The mutations introduced into OM that abolished MobC binding in vitro decreased 2-3 fold the frequency of mobilization of the test plasmids. The deletion of OM within the RA3 conjugative module had no effect on transfer if the mobC-nic operon was expressed from the heterologous promoter. If only nic was expressed from the heterologous promoter (no mobC) the conjugative transfer frequency of such plasmid was 1000-fold lower. Conclusion The MobC is an auxiliary transfer protein of dual function. It autoregulates the expression of mobC-nic operon while its presence significantly stimulates transfer efficiency. Electronic supplementary material The online version of this article (doi:10.1186/s12866-014-0235-1) contains supplementary material, which is available to authorized users.
Collapse
|
13
|
Identification of three noncontiguous regions on Bacillus anthracis plasmid pXO1 that are important for its maintenance. J Bacteriol 2014; 196:2921-33. [PMID: 24914182 DOI: 10.1128/jb.01747-14] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bacillus anthracis pXO1 minireplicon (MR) plasmid consisting of open reading frames (ORFs) GBAA_pXO1_0020 to GBAA_pXO1_0023 is not stably maintained in B. anthracis, whereas the full-size parent pXO1 plasmid (having 181,677 bp and 217 ORFs) is extremely stable under the same growth conditions. Two genetic tools developed for DNA manipulation in B. anthracis (Cre-loxP and Flp-FRT systems) were used to identify pXO1 regions important for plasmid stability. We localized a large segment of pXO1 that enables stable plasmid maintenance during vegetative growth. Further genetic analysis identified three genes that are necessary for pXO1 maintenance: amsP (GBAA_pXO1_0069), minP (GBAA_pXO1_0082), and sojP (GBAA_pXO1_0084). Analysis of conserved domains in the corresponding proteins indicated that only AmsP (activator of maintenance system of pXO1) is predicted to bind DNA, due to its strong helix-turn-helix domain. Two conserved domains were found in the MinP protein (Min protein from pXO1): an N-terminal domain having some similarity to the B. anthracis septum site-determining protein MinD and a C-terminal domain that resembles a baculovirus single-stranded-DNA-binding protein. The SojP protein (Soj from pXO1) contains putative Walker box motifs and belongs to the ParA family of ATPases. No sequences encoding other components of type I plasmid partition systems, namely, cis-acting centromere parS and its binding ParB protein, were identified within the pXO1 genome. A model describing the role of the MinP protein in pXO1 distribution between daughter cells is proposed.
Collapse
|
14
|
Ludwiczak M, Dolowy P, Markowska A, Szarlak J, Kulinska A, Jagura-Burdzy G. Global transcriptional regulator KorC coordinates expression of three backbone modules of the broad-host-range RA3 plasmid from IncU incompatibility group. Plasmid 2013; 70:131-45. [PMID: 23583562 DOI: 10.1016/j.plasmid.2013.03.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Revised: 03/28/2013] [Accepted: 03/29/2013] [Indexed: 11/17/2022]
Abstract
The broad-host-range conjugative RA3 plasmid from IncU incompatibility group has been isolated from the fish pathogen Aeromonas hydrophila. DNA sequencing has revealed a mosaic modular structure of RA3 with the stabilization module showing some similarity to IncP-1 genes and the conjugative transfer module highly similar to that from PromA plasmids. The integrity of the mosaic plasmid genome seems to be specified by its regulatory network. In this paper the transcriptional regulator KorC was analyzed. KorCRA3 (98 amino acids) is encoded in the stabilization region and represses four strong promoters by binding to a conserved palindrome sequence, designated OC on the basis of homology to the KorC operator sequences in IncP-1 plasmids. Two of the KorCRA3-regulated promoters precede the first two cistrons in the stabilization module, one fires towards replication module, remaining one controls a tricistronic operon, whose products are involved in the conjugative transfer process. Despite the similarity between the binding sites in IncU and IncP-1 plasmids, no cross-reactivity between their KorC proteins has been detected. KorC emerges as a global regulator of RA3, coordinating all its backbone functions: replication, stable maintenance and conjugative transfer.
Collapse
Affiliation(s)
- M Ludwiczak
- Department of Microbial Biochemistry, Institute of Biochemistry and Biophysics, PAS, Warsaw, Poland
| | | | | | | | | | | |
Collapse
|
15
|
Bartosik AA, Markowska A, Szarlak J, Kulińska A, Jagura-Burdzy G. Novel broad-host-range vehicles for cloning and shuffling of gene cassettes. J Microbiol Methods 2011; 88:53-62. [PMID: 22056795 DOI: 10.1016/j.mimet.2011.10.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2011] [Revised: 10/17/2011] [Accepted: 10/17/2011] [Indexed: 10/15/2022]
Abstract
Novel vectors for cloning and shuffling of gene cassettes based on minireplicon of broad-host-range RA3 plasmid from IncU incompatibility group were constructed. A series of minireplicon variants were prepared with copy number ranging from low (1-2 copies per chromosome), medium (10-15 copies per chromosome) to high copy number (80-90 copies per chromosome). The new cloning vectors are relatively small in size (4.5-5.4kb) and carry various resistance determinants: kanamycin (Km(R)), tetracycline (Tc(R)) or chloramphenicol (Cm(R)). The vectors were engineered to facilitate cloning and shuffling of the functional modules with or without transcriptional terminators. Using the described strategy, a bank of functional modules, ready for exchange, has been initiated.
Collapse
Affiliation(s)
- Aneta A Bartosik
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Pawinskiego 5A, Poland
| | | | | | | | | |
Collapse
|