Suppression of the thermosensitive replication phenotype of the derivative plasmid of pI9789::Tn552 inStaphylococcus aureusmay involve integration of the plasmid into the host chromosome

The carbazole-degradative plasmid pCAR1 carries the class II transposon Tn4676, which contains the car and ant genes, essential for conversion of carbazole into anthranilate, and anthranilate into catechol, respectively. In our previous study, DNA rearrangements in pCAR1 were frequently detected in the host Pseudomonas fluorescens Pf0-1 in the presence of carbazole, resulting in the improvement of host survivability. Several Pf0-1 mutants harbouring pCAR1 were isolated, and deletion of DNA in the plasmid ant gene was found. Here, we compared genome sequences of the parent strain Pf0-1L(pCAR1 : : rfp) and one of its mutants, 5EP83, to assess whether other DNA rearrangements occurred in either the plasmid or the host chromosome. We found transposition of Tn4676 into the 5EP83 chromosome. In addition, ISPre1 had transposed into the car gene intergenic region on the pCAR1-derivative plasmid of 5EP83, which inhibited car transcription. As a result of these transpositions, 5EP83 was able to metabolize carbazole due to the Tn4676 on its chromosome, although the car genes on its plasmid were non-functional. We also found that one copy of duplicate carAa genes had been deleted, and that ISPre4 had transposed into both the host chromosome and the plasmid. Our findings suggest that Pf0-1 harbouring pCAR1 is subjected to DNA rearrangements not only on the plasmid but also on its chromosome in the presence of carbazole.

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Genetic Mapping by Duplication Segregation in Salmonella enterica

Genetics ◽

10.1093/genetics/157.2.491 ◽

2001 ◽

Vol 157 (2) ◽

pp. 491-502

Author(s):

Eva M Camacho ◽

Josep Casadesús

Keyword(s):

Salmonella Enterica ◽

Replication Fork ◽

Limiting Factor ◽

Multiplicity Of Infection ◽

Dominant Marker ◽

Host Chromosome ◽

Transposon Insertion ◽

Large Size ◽

Chromosomal Duplication ◽

Duplication Segregation

Abstract MudP and MudQ elements were used to induce duplications in Salmonella enterica by formation of a triple crossover between two transduced fragments and the host chromosome. The large size (36 kb) of MudP and MudQ is a favorable trait for duplication formation, probably because homology length is a limiting factor for the central crossover. Additional requirements are a multiplicity of infection of 2 or higher in the infecting phage suspensions (which reflects the need of two transduced fragments) and an exponentially growing recipient (which reflects the need of a chromosome replication fork). We describe a set of 11 strains of S. enterica, each carrying a chromosomal duplication with known endpoints. The collection covers all the Salmonella chromosome except the terminus. For mapping, a dominant marker (e.g., a transposon insertion in or near the locus to be mapped) is transduced into the 11-strain set. Several transductants from each cross are grown nonselectively, and haploid segregants are scored for the presence of the marker. If all the segregants contain the transduced marker, it maps outside the duplication interval. If the marker is found only in a fraction of the segregants, it maps within the duplicated region.

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Two type IV secretion systems with different functions in Burkholderia cenocepacia K56-2

Microbiology ◽

10.1099/mic.0.033043-0 ◽

2009 ◽

Vol 155 (12) ◽

pp. 4005-4013 ◽

Cited By ~ 13

Author(s):

Ruifu Zhang ◽

John J. LiPuma ◽

Carlos F. Gonzalez

Keyword(s):

Type Iv Secretion ◽

Burkholderia Cenocepacia ◽

Target Cells ◽

Secretion Systems ◽

Type Iv ◽

Plasmid Mobilization ◽

Type Iv Secretion Systems ◽

Derivative Plasmid ◽

Chromosome Ii ◽

Bacterial Type

Bacterial type IV secretion systems (T4SS) perform two fundamental functions related to pathogenesis: the delivery of effector molecules to eukaryotic target cells, and genetic exchange. Two T4SSs have been identified in Burkholderia cenocepacia K56-2, a representative of the ET12 lineage of the B. cepacia complex (Bcc). The plant tissue watersoaking (Ptw) T4SS encoded on a resident 92 kb plasmid is a chimera composed of VirB/D4 and F-specific subunits, and is responsible for the translocation of effector(s) that have been linked to the Ptw phenotype. The bc-VirB/D4 system located on chromosome II displays homology to the VirB/D4 T4SS of Agrobacterium tumefaciens. In contrast to the Ptw T4SS, the bc-VirB/D4 T4SS was found to be dispensable for Ptw effector(s) secretion, but was found to be involved in plasmid mobilization. The fertility inhibitor Osa did not affect the secretion of Ptw effector(s) via the Ptw system, but did disrupt the mobilization of a RSF1010 derivative plasmid.

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Chromosome transfer inPseudomonas aeruginosamediated by R factors

Genetics Research ◽

10.1017/s0016672300012179 ◽

1971 ◽

Vol 17 (2) ◽

pp. 169-172 ◽

Cited By ~ 42

Author(s):

Vilma A. Stanisich ◽

B. W. Holloway

Keyword(s):

Pseudomonas Aeruginosa ◽

Specific Resistance ◽

Host Chromosome ◽

Chromosome Transfer ◽

R Factors

SUMMARYR factors present inPseudomonas aeruginosastrains of clinical origin can be transferred to other strains ofP. aeruginosaand may act to promote host chromosome transfer. In general, their properties are similar to those R factors in Enterobacteria. The different R factors studied vary with respect to transferability, transfer of specific resistance properties, repressibility, and ability to promote chromosome transfer.

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The synthesis of coliphage T1 DNA: Degradation of the host chromosome

Virology ◽

10.1016/0042-6822(81)90445-1 ◽

1981 ◽

Vol 108 (2) ◽

pp. 373-380 ◽

Cited By ~ 4

Author(s):

J.R. Christense ◽

D.H. Figurski ◽

W.H. Schreil

Keyword(s):

Dna Degradation ◽

Host Chromosome

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Interactions between Integrase and Excisionase in the Phage Lambda Excisive Nucleoprotein Complex

Journal of Bacteriology ◽

10.1128/jb.184.18.5200-5203.2002 ◽

2002 ◽

Vol 184 (18) ◽

pp. 5200-5203 ◽

Cited By ~ 34

Author(s):

Eun Hee Cho ◽

Richard I. Gumport ◽

Jeffrey F. Gardner

Keyword(s):

Protein Interactions ◽

Protein Protein Interactions ◽

Mobility Shift ◽

Host Chromosome ◽

Amino Terminal ◽

Nucleoprotein Complex ◽

Carboxyl Terminal ◽

Α Helix ◽

Gel Mobility Shift ◽

Amino Terminal Domain

ABSTRACT Bacteriophage lambda site-specific recombination comprises two overall reactions, integration into and excision from the host chromosome. Lambda integrase (Int) carries out both reactions. During excision, excisionase (Xis) helps Int to bind DNA and introduces a bend in the DNA that facilitates formation of the proper excisive nucleoprotein complex. The carboxyl-terminal α-helix of Xis is thought to interact with Int through direct protein-protein interactions. In this study, we used gel mobility shift assays to show that the amino-terminal domain of Int maintained cooperative interactions with Xis. This finding indicates that the amino-terminal arm-type DNA binding domain of Int interacts with Xis.

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An Artificially Constructed De Novo Human Chromosome Behaves Almost Identically to Its Natural Counterpart during Metaphase and Anaphase in Living Cells

Molecular and Cellular Biology ◽

10.1128/mcb.00355-06 ◽

2006 ◽

Vol 26 (20) ◽

pp. 7682-7695 ◽

Cited By ~ 16

Author(s):

Tomohiro Tsuduki ◽

Megumi Nakano ◽

Nao Yasuoka ◽

Saeko Yamazaki ◽

Teruaki Okada ◽

...

Keyword(s):

Yeast Artificial Chromosome ◽

Fluorescent Protein ◽

De Novo ◽

Artificial Chromosome ◽

Time Lapse ◽

Living Cells ◽

Lac Repressor ◽

Host Chromosome ◽

Artificial Chromosomes ◽

Spindle Midzone

ABSTRACT Human artificial chromosomes (HACs) are promising reagents for the analysis of chromosome function. While HACs are maintained stably, the segregation mechanisms of HACs have not been investigated in detail. To analyze HACs in living cells, we integrated 256 copies of the Lac operator into a precursor yeast artificial chromosome (YAC) containing α-satellite DNA and generated green fluorescent protein (GFP)-tagged HACs in HT1080 cells expressing a GFP-Lac repressor fusion protein. Time-lapse analyses of GFP-HACs and host centromeres in living mitotic cells indicated that the HAC was properly aligned at the spindle midzone and that sister chromatids of the HAC separated with the same timing as host chromosomes and moved to the spindle poles with mobility similar to that of the host centromeres. These results indicate that a HAC composed of a multimer of input α-satellite YACs retains most of the functions of the centromeres on natural chromosomes. The only difference between the HAC and the host chromosome was that the HAC oscillated more frequently, at higher velocity, across the spindle midzone during metaphase. However, this provides important evidence that an individual HAC has the capacity to maintain tensional balance in the pole-to-pole direction, thereby stabilizing its position around the spindle midzone.

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Integrase-Specific Enhancement and Suppression of Retroviral DNA Integration by Compacted Chromatin Structure In Vitro

Journal of Virology ◽

10.1128/jvi.78.11.5848-5855.2004 ◽

2004 ◽

Vol 78 (11) ◽

pp. 5848-5855 ◽

Cited By ~ 39

Author(s):

Konstantin D. Taganov ◽

Isabel Cuesta ◽

René Daniel ◽

Lisa Ann Cirillo ◽

Richard A. Katz ◽

...

Keyword(s):

Transcription Factors ◽

Chromatin Structure ◽

Site Selection ◽

Integration Site ◽

Histone H1 ◽

Detectable Effect ◽

Host Chromosome ◽

Dna Integration ◽

Hiv 1

ABSTRACT Integration of viral DNA into the host chromosome is an obligatory step in retroviral replication and is dependent on the activity of the viral enzyme integrase. To examine the influence of chromatin structure on retroviral DNA integration in vitro, we used a model target comprising a 13-nucleosome extended array that includes binding sites for specific transcription factors and can be compacted into a higher-ordered structure. We found that the efficiency of in vitro integration catalyzed by human immunodeficiency virus type 1 (HIV-1) integrase was decreased after compaction of this target with histone H1. In contrast, integration by avian sarcoma virus (ASV) integrase was more efficient after compaction by either histone H1 or a high salt concentration, suggesting that the compacted structure enhances this reaction. Furthermore, although site-specific binding of transcription factors HNF3 and GATA4 blocked ASV DNA integration in extended nucleosome arrays, local opening of H1-compacted chromatin by HNF3 had no detectable effect on integration, underscoring the preference of ASV for compacted chromatin. Our results indicate that chromatin structure affects integration site selection of the HIV-1 and ASV integrases in opposite ways. These distinct properties of integrases may also affect target site selection in vivo, resulting in an important bias against or in favor of integration into actively transcribed host DNA.

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Transduction studies on the relation between prophage and host chromosome

Journal of Molecular Biology ◽

10.1016/s0022-2836(65)80336-9 ◽

1965 ◽

Vol 12 (3) ◽

pp. 892-912 ◽

Cited By ~ 76

Author(s):

June L. Rothman

Keyword(s):

Host Chromosome

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Isolation and Characterization of the First Temperate Virus Infecting Psychrobacillus from Marine Sediments

Viruses ◽

10.3390/v14010108 ◽

2022 ◽

Vol 14 (1) ◽

pp. 108

Author(s):

Wang Liu ◽

Xiaowei Zheng ◽

Xin Dai ◽

Zhenfeng Zhang ◽

Wenyan Zhang ◽

...

Keyword(s):

Marine Sediments ◽

Hydrothermal Vent ◽

Okinawa Trough ◽

Marine Ecosystem ◽

Genome Replication ◽

Gene Encoding ◽

Significant Similarity ◽

Host Chromosome ◽

Isolation And Characterization

Viruses are far more abundant than cellular microorganisms in the marine ecosystem. However, very few viruses have so far been isolated from marine sediments, especially hydrothermal vent sediments, hindering the understanding of the biology and ecological functions of these tiny organisms. Here, we report the isolation and characterization of a temperate bacteriophage, named PVJ1, which infects Psychrobacillus from a hydrothermal vent field in Okinawa Trough. PVJ1 belongs to the Myoviridae family of the order Caudovirales. The tailed phage possesses a 53,187 bp linear dsDNA genome, with 84 ORFs encoding structural proteins, genome replication, host lysis, etc. in a modular pattern. The phage genome is integrated into the host chromosome near the 3′-end of deoD, a gene encoding purine nucleoside phosphorylase (PNP). The phage integration does not appear to disrupt the function of PNP. The phage DNA is packaged by the headful mechanism. Release of PVJ1 from the host cell was drastically enhanced by treatment with mitomycin C. Phages encoding an MCP sharing significant similarity (≥70% identical amino acids) with that of PVJ1 are widespread in diverse environments, including marine and freshwater sediments, soils, artificial ecosystems, and animal intestines, and primarily infect Firmicutes. These results are valuable to the understanding of the lifestyle and host interactions of bacterial viruses at the bottom of the ocean.

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