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Long S, Su M, Chen X, Hu A, Yu F, Zou Q, Cheng G. Proteomic and Mutant Analysis of Hydrogenase Maturation Protein Gene hypE in Symbiotic Nitrogen Fixation of Mesorhizobium huakuii. Int J Mol Sci 2023; 24:12534. [PMID: 37628715 PMCID: PMC10454058 DOI: 10.3390/ijms241612534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 08/01/2023] [Accepted: 08/04/2023] [Indexed: 08/27/2023] Open
Abstract
Hydrogenases catalyze the simple yet important redox reaction between protons and electrons and H2, thus mediating symbiotic interactions. The contribution of hydrogenase to this symbiosis and anti-oxidative damage was investigated using the M. huakuii hypE (encoding hydrogenase maturation protein) mutant. The hypE mutant grew a little faster than its parental 7653R and displayed decreased antioxidative capacity under H2O2-induced oxidative damage. Real-time quantitative PCR showed that hypE gene expression is significantly up-regulated in all the detected stages of nodule development. Although the hypE mutant can form nodules, the symbiotic ability was severely impaired, which led to an abnormal nodulation phenotype coupled to a 47% reduction in nitrogen fixation capacity. This phenotype was linked to the formation of smaller abnormal nodules containing disintegrating and prematurely senescent bacteroids. Proteomics analysis allowed a total of ninety differentially expressed proteins (fold change > 1.5 or <0.67, p < 0.05) to be identified. Of these proteins, 21 are related to stress response and virulence, 21 are involved in transporter activity, and 18 are involved in energy and nitrogen metabolism. Overall, the HypE protein is essential for symbiotic nitrogen fixation, playing independent roles in supplying energy and electrons, in bacterial detoxification, and in the control of bacteroid differentiation and senescence.
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Affiliation(s)
| | | | | | | | | | | | - Guojun Cheng
- Hubei Provincial Engineering and Technology Research Center for Resources and Utilization of Microbiology, College of Life Sciences, South-Central Minzu University, Wuhan 430074, China
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Hu A, Chen X, Luo S, Zou Q, Xie J, He D, Li X, Cheng G. Rhizobium leguminosarum Glutathione Peroxidase Is Essential for Oxidative Stress Resistance and Efficient Nodulation. Front Microbiol 2021; 12:627562. [PMID: 33633710 PMCID: PMC7900000 DOI: 10.3389/fmicb.2021.627562] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 01/04/2021] [Indexed: 11/30/2022] Open
Abstract
Glutathione (GSH) plays a key role in regulating the cellular Redox Homeostasis, and appears to be essential for initiation and development of root nodules. Glutathione peroxidase (Gpx) catalyzes the reduction of H2O2 and organic hydroperoxides by oxidation of GSH to oxidized GSH (GSSG), which in turn is reduced by glutathione reductase (GR). However, it has not been determined whether the Rhizobium leguminosarum Gpx or GR is required during symbiotic interactions with pea. To characterize the role of glutathione-dependent enzymes in the symbiotic process, single and double mutants were made in gpxA (encoding glutathione peroxidase) and gshR (encoding glutathione reductase) genes. All the mutations did not affect the rhizobial growth, but they increased the sensitivity of R. leguminosarum strains to H2O2. Mutant in GpxA had no effect on intracellular GSH levels, but can increase the expression of the catalase genes. The gshR mutant can induce the formation of normal nodules, while the gpxA single and double mutants exhibited a nodulation phenotype coupled to more than 50% reduction in the nitrogen fixation capacity, these defects in nodulation were characterized by the formation of ineffective nodules. In addition, the gpxA and gshR double mutant was severely impaired in rhizosphere colonization and competition. Quantitative proteomics using the TMT labeling method was applied to study the differential expression of proteins in bacteroids isolated from pea root nodules. A total of 27 differentially expressed proteins were identified in these root bacteroids including twenty down-regulated and seven up-regulated proteins. By sorting the down-regulated proteins, eight are transporter proteins, seven are dehydrogenase, deoxygenase, oxidase, and hydrolase. Moreover, three down-regulating proteins are directly involved in nodule process.
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Affiliation(s)
- Aiqi Hu
- Hubei Provincial Engineering and Technology Research Center for Resources and Utilization of Microbiology, College of Life Sciences, South-Central University for Nationalities, Wuhan, China
| | - Xiaohong Chen
- Hubei Provincial Engineering and Technology Research Center for Resources and Utilization of Microbiology, College of Life Sciences, South-Central University for Nationalities, Wuhan, China
| | - Sha Luo
- Hubei Provincial Engineering and Technology Research Center for Resources and Utilization of Microbiology, College of Life Sciences, South-Central University for Nationalities, Wuhan, China
| | - Qian Zou
- Hubei Provincial Engineering and Technology Research Center for Resources and Utilization of Microbiology, College of Life Sciences, South-Central University for Nationalities, Wuhan, China
| | - Jing Xie
- Hubei Provincial Engineering and Technology Research Center for Resources and Utilization of Microbiology, College of Life Sciences, South-Central University for Nationalities, Wuhan, China
| | - Donglan He
- Hubei Provincial Engineering and Technology Research Center for Resources and Utilization of Microbiology, College of Life Sciences, South-Central University for Nationalities, Wuhan, China
| | - Xiaohua Li
- Hubei Provincial Engineering and Technology Research Center for Resources and Utilization of Microbiology, College of Life Sciences, South-Central University for Nationalities, Wuhan, China
| | - Guojun Cheng
- Hubei Provincial Engineering and Technology Research Center for Resources and Utilization of Microbiology, College of Life Sciences, South-Central University for Nationalities, Wuhan, China
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Antioxidant ability of glutaredoxins and their role in symbiotic nitrogen fixation in Rhizobium leguminosarum bv. viciae 3841. Appl Environ Microbiol 2021; 87:AEM.01956-20. [PMID: 33277272 PMCID: PMC7851698 DOI: 10.1128/aem.01956-20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Glutaredoxins (Grx) are redoxin family proteins that reduce disulfides and mixed disulfides between glutathione and proteins. Rhizobium leguminosarum bv. Viciae 3841 contains three genes coding for glutaredoxins: RL4289 (grxA) codes for a dithiolic glutaredoxin, RL2615 (grxB) codes for a monothiol glutaredoxin, while RL4261 (grxC) codes for a glutaredoxin-like NrdH protein. We generated mutants interrupted in one, two, or three glutaredoxin genes. These mutants had no obvious differences in growth phenotypes from the wild type RL3841. However, while a mutant of grxC did not affect the antioxidant or symbiotic capacities of R. leguminosarum, grxA-derived or grxB mutants decreased antioxidant and nitrogen fixation capacities. Furthermore, grxA mutants were severely impaired in rhizosphere colonization, and formed smaller nodules with defects of bacteroid differentiation, whereas nodules induced by grxB mutants contained abnormally thick cortices and prematurely senescent bacteroids. The grx triple mutant had the greatest defect in antioxidant and symbiotic capacities of R. leguminosarum and quantitative proteomics revealed it had 56 up-regulated and 81 down-regulated proteins relative to wildtype. Of these proteins, twenty-eight are involved in transporter activity, twenty are related to stress response and virulence, and sixteen are involved in amino acid metabolism. Overall, R. leguminosarum glutaredoxins behave as antioxidant proteins mediating root nodule symbiosis.IMPORTANCE Glutaredoxin catalyzes glutathionylation/deglutathionylation reactions, protects SH-groups from oxidation and restores functionally active thiols. Three glutaredoxins exist in R. leguminosarum and their properties were investigated in free-living bacteria and during nitrogen-fixing symbiosis. All the glutaredoxins were necessary for oxidative stress defense. Dithiol GrxA affects nodulation and nitrogen fixation of bacteroids by altering deglutathionylation reactions, monothiol GrxB is involved in symbiotic nitrogen fixation by regulating Fe-S cluster biogenesis, and GrxC may participate in symbiosis by an unknown mechanism. Proteome analysis provides clues to explain the differences between the grx triple mutant and wild-type nodules.
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Zou Q, Luo S, Wu H, He D, Li X, Cheng G. A GMC Oxidoreductase GmcA Is Required for Symbiotic Nitrogen Fixation in Rhizobium leguminosarum bv. viciae. Front Microbiol 2020; 11:394. [PMID: 32265862 PMCID: PMC7105596 DOI: 10.3389/fmicb.2020.00394] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 02/26/2020] [Indexed: 11/13/2022] Open
Abstract
GmcA is a FAD-containing enzyme belonging to the GMC (glucose-methanol-choline oxidase) family of oxidoreductases. A mutation in the Rhizobium leguminosarum gmcA gene was generated by homologous recombination. The mutation in gmcA did not affect the growth of R. leguminosarum, but it displayed decreased antioxidative capacity at H2O2 conditions higher than 5 mM. The gmcA mutant strain displayed no difference of glutathione reductase activity, but significantly lower level of the glutathione peroxidase activity than the wild type. Although the gmcA mutant was able to induce the formation of nodules, the symbiotic ability was severely impaired, which led to an abnormal nodulation phenotype coupled to a 30% reduction in the nitrogen fixation capacity. The observation on ultrastructure of 4-week pea nodules showed that the mutant bacteroids tended to start senescence earlier and accumulate poly-β-hydroxybutyrate (PHB) granules. In addition, the gmcA mutant was severely impaired in rhizosphere colonization. Real-time quantitative PCR showed that the gmcA gene expression was significantly up-regulated in all the detected stages of nodule development, and statistically significant decreases in the expression of the redoxin genes katG, katE, and ohrB were found in gmcA mutant bacteroids. LC-MS/MS analysis quantitative proteomics techniques were employed to compare differential gmcA mutant root bacteroids in response to the wild type infection. Sixty differentially expressed proteins were identified including 33 up-regulated and 27 down-regulated proteins. By sorting the identified proteins according to metabolic function, 15 proteins were transporter protein, 12 proteins were related to stress response and virulence, and 9 proteins were related to transcription factor activity. Moreover, nine proteins related to amino acid metabolism were over-expressed.
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Affiliation(s)
- Qian Zou
- Hubei Provincial Engineering and Technology Research Center for Resources and Utilization of Microbiology, College of Life Sciences, South-Central University for Nationalities, Wuhan, China
| | - Sha Luo
- Hubei Provincial Engineering and Technology Research Center for Resources and Utilization of Microbiology, College of Life Sciences, South-Central University for Nationalities, Wuhan, China
| | - Hetao Wu
- Hubei Provincial Engineering and Technology Research Center for Resources and Utilization of Microbiology, College of Life Sciences, South-Central University for Nationalities, Wuhan, China
| | - Donglan He
- Hubei Provincial Engineering and Technology Research Center for Resources and Utilization of Microbiology, College of Life Sciences, South-Central University for Nationalities, Wuhan, China
| | - Xiaohua Li
- Hubei Provincial Engineering and Technology Research Center for Resources and Utilization of Microbiology, College of Life Sciences, South-Central University for Nationalities, Wuhan, China
| | - Guojun Cheng
- Hubei Provincial Engineering and Technology Research Center for Resources and Utilization of Microbiology, College of Life Sciences, South-Central University for Nationalities, Wuhan, China
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Luo S, Yin J, Peng Y, Xie J, Wu H, He D, Li X, Cheng G. Glutathione is Involved in Detoxification of Peroxide and Root Nodule Symbiosis of Mesorhizobium huakuii. Curr Microbiol 2019; 77:1-10. [PMID: 31624868 DOI: 10.1007/s00284-019-01784-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Accepted: 09/30/2019] [Indexed: 02/07/2023]
Abstract
Legumes interact with symbiotic rhizobia to produce nitrogen-fixation root nodules under nitrogen-limiting conditions. The contribution of glutathione (GSH) to this symbiosis and anti-oxidative damage was investigated using the M. huakuii gshB (encoding GSH synthetase) mutant. The gshB mutant grew poorly with different monosaccharides, including glucose, sucrose, fructose, maltose, or mannitol, as sole sources of carbon. The antioxidative capacity of gshB mutant was significantly decreased by these treatments with H2O2 under the lower concentrations and cumene hydroperoxide (CUOOH) under the higher concentrations, indicating that GSH plays different roles in response to organic peroxide and inorganic peroxide. The gshB mutant strain displayed no difference in catalase activity, but significantly lower levels of the peroxidase activity and the glutathione reductase activity than the wild type. The same level of catalase activity could be associated with upregulation of the transcriptional activity of the catalase genes under H2O2-induced conditions. The nodules infected by the gshB mutant were severely impaired in abnormal nodules, and showed a nodulation phenotype coupled to a 60% reduction in the nitrogen fixation capacity. A 20-fold decrease in the expression of two nitrogenase genes, nifH and nifD, is observed in the nodules induced by gshB mutant strain. The symbiotic deficiencies were linked to bacteroid early senescence.
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Affiliation(s)
- Sha Luo
- Hubei Provincial Engineering and Technology Research Center for Resources and Utilization of Microbiology, College of Life Sciences, South-Central University for Nationalities, Wuhan, 430074, Hubei, China
| | - Jie Yin
- Hubei Provincial Engineering and Technology Research Center for Resources and Utilization of Microbiology, College of Life Sciences, South-Central University for Nationalities, Wuhan, 430074, Hubei, China
| | - Yang Peng
- Hubei Provincial Engineering and Technology Research Center for Resources and Utilization of Microbiology, College of Life Sciences, South-Central University for Nationalities, Wuhan, 430074, Hubei, China
| | - Jing Xie
- Hubei Provincial Engineering and Technology Research Center for Resources and Utilization of Microbiology, College of Life Sciences, South-Central University for Nationalities, Wuhan, 430074, Hubei, China
| | - Hetao Wu
- Hubei Provincial Engineering and Technology Research Center for Resources and Utilization of Microbiology, College of Life Sciences, South-Central University for Nationalities, Wuhan, 430074, Hubei, China
| | - Donglan He
- Hubei Provincial Engineering and Technology Research Center for Resources and Utilization of Microbiology, College of Life Sciences, South-Central University for Nationalities, Wuhan, 430074, Hubei, China
| | - Xiaohua Li
- Hubei Provincial Engineering and Technology Research Center for Resources and Utilization of Microbiology, College of Life Sciences, South-Central University for Nationalities, Wuhan, 430074, Hubei, China
| | - Guojun Cheng
- Hubei Provincial Engineering and Technology Research Center for Resources and Utilization of Microbiology, College of Life Sciences, South-Central University for Nationalities, Wuhan, 430074, Hubei, China.
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Wang S, Lu T, Xue Q, Xu K, Cheng G. Antioxidation and symbiotic nitrogen fixation function of prxA gene in Mesorhizobium huakuii. Microbiologyopen 2019; 8:e889. [PMID: 31177643 PMCID: PMC6813433 DOI: 10.1002/mbo3.889] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2019] [Revised: 05/20/2019] [Accepted: 05/20/2019] [Indexed: 02/06/2023] Open
Abstract
Peroxiredoxins (Prxs) play an essential role in the antioxidant activity and symbiotic capacity of Mesorhizobium huakuii. A mutation in the M. huakuii prxA gene (encoding a Prx5‐like peroxiredoxin) was generated by homologous recombination. The mutation of prxA did not affect M. huakuii growth, but the strain displayed decreased antioxidative capacity under organic cumene hydroperoxide (CUOOH) conditions. The higher resistance of the prxA mutant strain compared with the wild‐type strain to more than 1 mmol/L H2O2 was associated with a significantly higher level of glutathione reductase activity and a significantly lower level of intracellular hydrogen peroxide content. Real‐time quantitative PCR showed that under 1 mmol/L H2O2 conditions, expression of the stress‐responsive genes katG and katE was significantly upregulated in the prxA mutant. Although the prxA mutant can form nodules, the symbiotic ability was severely impaired, which led to an abnormal nodulation phenotype coupled to a 53.25% reduction in nitrogen fixation capacity. This phenotype was linked to an absence of bacteroid differentiation and deregulation of the transcription of the symbiotic genes nifH, nifD, and fdxN. Expression of the prxA gene was induced during symbiosis. Thus, the PrxA protein is essential for antioxidant capacity and symbiotic nitrogen fixation, playing independent roles in bacterial differentiation and cellular antioxidative systems.
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Affiliation(s)
- Sanjiao Wang
- College of Life Sciences, South-Central University for Nationalities, Wuhan, Hubei, China
| | - Tiantian Lu
- College of Life Sciences, South-Central University for Nationalities, Wuhan, Hubei, China
| | - Qiang Xue
- College of Life Sciences, South-Central University for Nationalities, Wuhan, Hubei, China
| | - Ke Xu
- College of Life Sciences, South-Central University for Nationalities, Wuhan, Hubei, China
| | - Guojun Cheng
- College of Life Sciences, South-Central University for Nationalities, Wuhan, Hubei, China.,Hubei Provincial Engineering and Technology Research Center for Resources and Utilization of Microbiology, College of Life Sciences, South-Central University for Nationalities, Wuhan, Hubei, China
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Pooyan S, George MLC, Borthakur D. Characterization of a Rhizobium etli chromosomal gene required for nodule development on Phaseolus vulgaris L. World J Microbiol Biotechnol 2014; 10:583-9. [DOI: 10.1007/bf00367673] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 05/27/1994] [Accepted: 06/01/1994] [Indexed: 11/30/2022]
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PAIN AN. Symbiotic Properties of Antibiotic-Resistant and Auxotrophic Mutants ofRhizobium leguminosarum. ACTA ACUST UNITED AC 2008. [DOI: 10.1111/j.1365-2672.1979.tb01169.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Quandt J, Clark RG, Venter AP, Clark SRD, Twelker S, Hynes MF. Modified RP4 and Tn5-Mob derivatives for facilitated manipulation of large plasmids in Gram-negative bacteria. Plasmid 2004; 52:1-12. [PMID: 15212888 DOI: 10.1016/j.plasmid.2004.04.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2003] [Revised: 04/07/2004] [Indexed: 11/23/2022]
Abstract
We have constructed a set of RP4 (NmS/TcS) and Tn5-Mob derivatives which have applications in experiments involving mobilization of replicons in many Gram-negative organisms. The different selection markers of the RP4 and Tn5-Mob derivatives include streptomycin, chloramphenicol, gentamicin, and spectinomycin resistance as well as mercury resistance, and a constitutively expressed lacZ gene. This choice of markers allows the use of these derivatives in bacteria which are naturally resistant to many antibiotics, and in strains which contain pre-existing resistance plasmids, transposons, or antibiotic cassette insertions. In addition, a RP4 derivative carrying the sacB gene of Bacillus subtilis was constructed. This allows the selection for the loss of RP4 after it has been used to mobilize other plasmids. A Tn5-Mob-sacB derivative with a new marker (Gm) was also developed, as were vectors which take advantage of the sacB gene to facilitate replacement of existing Tn5 inserts with other Tn5 derivatives. As an example of the use of these tools, three Rhizobium leguminosarum bv. viciae VF39 plasmids which have been shown to be involved in symbiosis were differentially tagged and mobilized (individually and in various combinations) to the plasmid-free Agrobacterium tumefaciens strain UBAPF2. None of the resultant Agrobacterium strains was able to fix nitrogen in symbiosis with peas.
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Affiliation(s)
- Jürgen Quandt
- Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary AB, Canada T2N 1N4
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Evidence for two uptake systems in Rhizobium leguminosarum for hydroxy-aromatic compounds metabolized by the 3-oxoadipate pathway. Arch Microbiol 1991. [DOI: 10.1007/bf00248715] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Abstract
Iron acquisition by symbiotic Rhizobium spp. is essential for nitrogen fixation in the legume root nodule symbiosis. Rhizobium leguminosarum 116, an ineffective mutant strain with a defect in iron acquisition, was isolated after nitrosoguanidine mutagenesis of the effective strain 1062. The pop-1 mutation in strain 116 imparted to it a complex phenotype, characteristic of iron deficiency: the accumulation of porphyrins (precursors of hemes) so that colonies emitted a characteristic pinkish-red fluorescence when excited by UV light, reduced levels of cytochromes b and c, and wild-type growth on high-iron media but low or no growth in low-iron broth and on solid media supplemented with the iron scavenger dipyridyl. Several iron(III)-solubilizing agents, such as citrate, hydroxyquinoline, and dihydroxybenzoate, stimulated growth of 116 on low-iron solid medium; anthranilic acid, the R. leguminosarum siderophore, inhibited low-iron growth of 116. The initial rate of 55Fe uptake by suspensions of iron-starved 116 cells was 10-fold less than that of iron-starved wild-type cells. Electron microscopic observations revealed no morphological abnormalities in the small, white nodules induced by 116. Nodule cortical cells were filled with vesicles containing apparently normal bacteroids. No premature degeneration of bacteroids or of plant cell organelles was evident. We mapped pop-1 by R plasmid-mediated conjugation and recombination to the ade-27-rib-2 region of the R. leguminosarum chromosome. No segregation of pop-1 and the symbiotic defect was observed among the recombinants from these crosses. Cosmid pKN1, a pLAFR1 derivative containing a 24-kilobase-pair fragment of R. leguminosarum DNA, conferred on 116 the ability to grow on dipyridyl medium and to fix nitrogen symbiotically. These results indicate that the insert cloned in pKN1 encodes an element of the iron acquisition system of R. leguminosarum that is essential for symbiotic nitrogen fixation.
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Mapping of some genes involved in C-1 metabolism in the facultative methylotroph Methylobacterium sp strain AM1 (Pseudomonas AM1). Arch Microbiol 1985. [DOI: 10.1007/bf00411043] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Simon R. High frequency mobilization of gram-negative bacterial replicons by the in vitro constructed Tn5-Mob transposon. MOLECULAR & GENERAL GENETICS : MGG 1984; 196:413-20. [PMID: 6094969 DOI: 10.1007/bf00436188] [Citation(s) in RCA: 325] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
A DNA fragment of the broad host range plasmid RP4 carrying the cis-acting DNA recognition site for conjugative DNA transfer between bacterial cells (Mobsite) was cloned into the kanamycin-neomycin resistance transposon Tn5. Using conventional transposon mutagenesis techniques the new transposon, called Tn5-Mob, can easily be inserted into the host DNA of gram-negative bacteria. A host replicon carrying Tn5-Mob is then mobilizable into any other gram-negative species if the transfer functions of plasmid RP4 are provided in trans. The potential of Tn5-Mob was demonstrated by mobilizing Rhizobium meliloti plasmids as well as the E. coli chromosome at high frequencies.
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Finan TM, Hartweig E, LeMieux K, Bergman K, Walker GC, Signer ER. General transduction in Rhizobium meliloti. J Bacteriol 1984; 159:120-4. [PMID: 6330024 PMCID: PMC215601 DOI: 10.1128/jb.159.1.120-124.1984] [Citation(s) in RCA: 231] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
General transduction by phage phi M12 in Rhizobium meliloti SU47 and its derivatives is described. Cotransduction and selection for Tn5 insertions which are closely linked to specific loci were demonstrated. A derivative of SU47 carrying the recA::Tn5 allele of R. meliloti 102F34 could be transduced for plasmid R68.45 but not for chromosomally located alleles. Phage phi M12 is morphologically similar to Escherichia coli phage T4, and restriction endonuclease analysis indicated that the phage DNA was ca. 160 kilobases in size.
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Lejeune P, Mergeay M, Van Gijsegem F, Faelen M, Gerits J, Toussaint A. Chromosome transfer and R-prime plasmid formation mediated by plasmid pULB113 (RP4::mini-Mu) in Alcaligenes eutrophus CH34 and Pseudomonas fluorescens 6.2. J Bacteriol 1983; 155:1015-26. [PMID: 6411681 PMCID: PMC217794 DOI: 10.1128/jb.155.3.1015-1026.1983] [Citation(s) in RCA: 76] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Plasmid pULB113 (RP4::mini-Mu), which contains the mini-Mu transposon, promoted both homologous and heterologous gene transfer from Pseudomonas fluorescens 6.2 and Alcaligenes eutrophus CH34. Homologous gene transfer in P. fluorescens 6.2 and A. eutrophus CH34 occurred at a frequency of 10(-4) to 10(-5), and recombinants inherited unselected recessive markers, suggesting a process of chromosome mobilization. Loci involved in autotrophic growth were among those transferred in A. eutrophus. In heterospecific matings, markers were transferred from P. fluorescens to A. eutrophus, Salmonella typhimurium LT2, and Escherichia coli, from A. eutrophus to P. fluorescens, and from Erwinia carotovora subsp. chrysanthemi to A. eutrophus. Heterospecific matings resulted in the formation of R-prime plasmids at frequencies of 10(-7) to 10(-4) per transferred plasmid. When S. typhimurium was the recipient, we observed R-prime plasmids with both restriction-proficient and restriction-deficient strains, although restriction markedly affected the frequency of transfer of pULB113. R-prime plasmids were quite stable, but lost the transposed marker more easily in a rec+ background than in a recA background, suggesting excision of transposed material by reciprocal recombination between flanking copies of mini-Mu. R-prime plasmids could be transferred easily into different recipients and were used in complementation studies. PstI restriction digests of four R-prime plasmids carrying P. fluorescens 6.2 DNA showed a number of additional bands, suggesting that several genes were transposed together with the selected marker on the plasmid.
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Barrett JT, Rhodes CS, Ferber DM, Jenkins B, Kuhl SA, Ely B. Construction of a genetic map for Caulobacter crescentus. J Bacteriol 1982; 149:889-96. [PMID: 6949897 PMCID: PMC216475 DOI: 10.1128/jb.149.3.889-896.1982] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
RP4-mediated conjugation has been used to transfer large fragments of chromosomal material in Caulobacter crescentus. In this system, conjugation proceeds from multiple origins, and haploid recombinants are recovered at frequencies of 10(-6) and 10(-7) per donor cell. The data from five-factor crosses were subjected to computer-assisted crossover analyses as a rapid method to determine marker order. Using this information and data from additional two- and three-factor crosses mediated by RP4 or the generalized transducing bacteriophage phi Cr30, we constructed the first genetic map for C. crescentus.
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Megias M, Caviedes MA, Palomares AJ, Perezsilva J. Use of plasmid R68.45 for constructing a circular linkage map of the Rhizobium trifolii chromosome. J Bacteriol 1982; 149:59-64. [PMID: 6947977 PMCID: PMC216592 DOI: 10.1128/jb.149.1.59-64.1982] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Plasmid R68.45 was used to promote conjugal transfer of chromosomal markers in Rhizobium trifolii RS55. Analysis of two-factor and three-factor crosses among R. trifolii strains enabled construction of a circular linkage map of the R. trifolii chromosome, containing 17 nutritional and resistance markers.
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Currier TC, Morgan MK. Restriction endonuclease analyses of the incompatibility group P-1 plasmids RK2, RP1, RP4, R68, and R68.45. Curr Microbiol 1981. [DOI: 10.1007/bf01566742] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Thomson JA, Hendson M, Magnes RM. Mutagenesis by insertion of drug resistance transposon Tn7 into a vibrio species. J Bacteriol 1981; 148:374-8. [PMID: 6270064 PMCID: PMC216204 DOI: 10.1128/jb.148.1.374-378.1981] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
A halotolerant, collagenolytic strain of Vibrio sp. was conjugated with an Escherichia coli strain carrying plasmid RP4. The plasmid was transferred to and maintained in the Vibrio and could be subsequently transferred in matings to suitably marked stains of the same species. After conjugation with an E. coli carrying the cointegrate plasmid RP4::Mu cts61::Tn7, Vibrio transconjugants were selected that carried Tn7 inserted into the bacterial chromosome. A large proportion of these transconjugants were auxotrophic, showing that plasmid suicide by Mu can be used to isolate Tn7-derived mutants in Vibrio. Approximately half of the auxotrophs isolate Tn7-derived mutants in Vibrio. Approximately half of the auxotrophs isolated were ilv mutants, all of which exhibited the same phenotype. Thus, although Tn7 insertion can induce auxotrophy, including trp, thy, his and ura, in Vibrio, there does appear to be a hot spot for integration in the ilv operon.
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21
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Grinter NJ. Analysis of chromosome mobilization using hybrids between plasmid RP4 and a fragment of bacteriophage lambda carrying IS1. Plasmid 1981; 5:267-76. [PMID: 6267631 DOI: 10.1016/0147-619x(81)90004-4] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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22
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Pilacinski WP, Schmidt EL. Plasmid transfer within and between serologically distinct strains of Rhizobium japonicum, using antibiotic resistance mutants and auxotrophs. J Bacteriol 1981; 145:1025-30. [PMID: 7007335 PMCID: PMC217213 DOI: 10.1128/jb.145.2.1025-1030.1981] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Methionine-requiring and pantothenic acid-requiring auxotrophs of Rhizobium japanicum USDA 31, as well as highly antibiotic-resistant mutants of R. japonicum strains USDA 31, USDA 110, USDA 138, and Webster 48, were isolated. These mutants were used to transfer the P-1 group plasmids R68.45 and RP4 within and between strains USDA 31, USDA 110, and Webster 48. Attempts to demonstrate transfer of either plasmid to strain USDA 138 were unsuccessful.
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23
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24
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The genetic analysis of Rhizobium in relation to symbiotic nitrogen fixation. Heredity (Edinb) 1980. [DOI: 10.1038/hdy.1980.59] [Citation(s) in RCA: 64] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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25
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Abstract
Conjugal transfer of three IncP1 plasmids and one IncFII plasmid into strains of the ethanol-producing bacterium
Zymomonas mobilis
was obtained. These plasmids were transferred at high frequencies from
Escherichia coli
and
Pseudomonas aeruginosa
into
Z. mobilis
and also between different
Z. mobilis
strains, using the membrane filter mating technique. Most of the plasmids were stably maintained in
Z. mobilis
, although there was some evidence of delayed marker expression. A low level of chromosomal gene transfer, mediated by plasmid R68.45, was detected between
Z. mobilis
strains. Genetic evidence suggesting that
Z. mobilis
may be more closely related to
E. coli
than to
Pseudomonas
or
Rhizobium
is discussed.
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Affiliation(s)
- M L Skotnicki
- School of Biological Technology, University of New South Wales, Kensington, New South Wales 2033, Australia
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26
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Kondorosi A, Vincze E, Johnston AWB, Beringer JE. A comparison of three Rhizobium linkage maps. ACTA ACUST UNITED AC 1980. [DOI: 10.1007/bf00270491] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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27
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Ludwig RA, Johansen E. DnaG-suppressing variants of R68.45 with enhanced chromosome donating ability in Rhizobium. Plasmid 1980; 3:359-61. [PMID: 6100901 DOI: 10.1016/0147-619x(80)90049-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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28
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Buchanan-Wollaston AV, Beringer JE, Brewin NJ, Hirsch PR, Johnston AWB. Isolation of symbiotically defective mutants in Rhizobium leguminosarum by insertion of the transposon Tn5 into a transmissible plasmid. ACTA ACUST UNITED AC 1980. [DOI: 10.1007/bf00267228] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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29
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Paraskeva C. Transfer of kanamycin resistance mediated by plasmid R68.45 in Paracoccus denitrificans. J Bacteriol 1979; 139:1062-4. [PMID: 479105 PMCID: PMC218057 DOI: 10.1128/jb.139.3.1062-1064.1979] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Plasmid R68.45 mediates the transfer of kanamycin resistance from Pseudomonas aeruginosa to Paracoccus denitrificans. Kanamycin resistance could be transferred from one strain of P. denitrificans to another, thus opening up the possibility of using R68.45 as a sex factor in P. denitrificans.
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30
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Jeyaseelan K, Guest J. Transfer of antibiotic resistance to facultative methylotrophs with plasmid R68.45. FEMS Microbiol Lett 1979. [DOI: 10.1111/j.1574-6968.1979.tb04283.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
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31
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Casadesús J, Olivares J. Rough and fine linkage mapping of the Rhizobium meliloti chromosome. MOLECULAR & GENERAL GENETICS : MGG 1979; 174:203-9. [PMID: 290852 DOI: 10.1007/bf00268356] [Citation(s) in RCA: 65] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
A circular linkage map of the Rhizobium meliloti chromosome, obtained from R68.45-mediated crosses, has been revised by cotransductional analysis, after general transduction by DF2 phage. Three short chromosomal regions have been mapped by cotransduction. Comparison between conjugal and cotransductional data suggests that R68.45-mediated linkage measures are indeed rough. Cotransduction seems to be a useful tool for improving the linkage map of R. meliloti.
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32
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Hamada SE, Luckey JP, Farrand SK. R-plasmid-mediated chromosomal gene transfer in Agrobacterium tumefaciens. J Bacteriol 1979; 139:280-6. [PMID: 457601 PMCID: PMC216856 DOI: 10.1128/jb.139.1.280-286.1979] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Although several techniques are available for transferring the Ti plasmids from one strain of agrobacterium tumefaciens to another, there are no reproducible methods for analysis of chromosomal markers in this phytopathogen. The R plasmid, R68.45, is known to show chromosomal mobilizing ability in several bacterial genera including the closely related Rhizobia. R68.45 was transferred into the prototrophic A. tumefaciens strain 15955. Ten kanamycin-resistant transconjugant clones were tested for chromosomal mobilizing ability by mating with strain SA10, rifampin- and streptomycin-resistant histidine auxotroph of strain 15955. Of the 10 donor clones, 2 showed high chromosomal mobilizing ability. Between 1,000 and 2,000 His+ colony-forming units per ml were obtained, a value 10 to 20 times greater than can be accounted for by spontaneous reversion. Sequential recloning and matings resulted in the isolation of relatively stable donor cultures. Chromosome gene transfer is dependent upon the presence in the donor of R68.45. Donors lacking an R plasmid or harboring the closely related plasmid RP4 failed to yield His+ transconjugants. With strain SA11, a methionine auxotroph of strain SA10, coinheritance of histidine and methionine independence could be demonstrated. Approximately half of the transconjugants also inherited R68.45. These results indicate that A. tumefaciens 15955 is capable of undergoing host chromosomal genetic exchange.
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33
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Tucker W, Pemberton J. Conjugation and chromosome transfer inRhodopseudomonas sphaeroidesmediated by W and P group plasmids. FEMS Microbiol Lett 1979. [DOI: 10.1111/j.1574-6968.1979.tb03273.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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34
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35
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Montoya AL, Moore LW, Gordon MP, Nester EW. Multiple genes coding for octopine-degrading enzymes in Agrobacterium. J Bacteriol 1978; 136:909-15. [PMID: 721779 PMCID: PMC218524 DOI: 10.1128/jb.136.3.909-915.1978] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Most biotype 2 strains of Agrobacterium tumefaciens and A. radiobacter which utilize nopaline also degrade octopine. In all such strains studied, the ability to degrade octopine did not appear to be transferred to plasmidless recipient cells under conditions of plasmid transfer in which the ability to utilize nopaline was transferred. An octopine-degrading mutant was isolated in a strain cured of its plasmid, suggesting that genes of octopine degradation may have a chromosomal location in some strains. In strains in which octopine utilization is coded by plasmid genes, octopine degradation was always inducible, whereas in strains which degrade both octopine and nopaline, octopine utilization was constitutive although nopaline degradation was inducible. When plasmids coding for octopine-utilizing ability were transformed into a strain containing either a nopaline- or null-type plasmid, transformants able to degrade octopine were either not observed or were unstable upon purification. All of these data suggest that plasmids associated with virulence are incompatible with one another, and therefore imply that the major groups of plasmids associated with virulence have a common origin.
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36
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Abstract
The IncP-1 plasmid R68 and variants R68.45 and R68.185 were tested for their chromosome donor ability in a selected recipient of Pseudomonas glycinea PGR12. It was found that variants did not express their selected characteristic of increased donor ability over that of R68 or R68.5, our commonly used donor plasmids. Coinheritance analysis of a variety of crosses provides evidence of a linkage group comprising 11 loci.
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37
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Johnston AW, Bibb MJ, Beringer JE. Tryptophan genes in Rhizobium--their organization and their transfer to other bacterial genera. MOLECULAR & GENERAL GENETICS : MGG 1978; 165:323-30. [PMID: 105238 DOI: 10.1007/bf00332533] [Citation(s) in RCA: 41] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
R. leguminosarum trp alleles mapped by R68.45-mediated recombination were located in three distinct chromosomal regions. We isolated three derivatives of R68.45 that carried different trp genes of R. meliloti. Each of the plasmids suppressed all of the R. leguminosarum trp alleles in a particular region. The R-primes were transferred to strains of P. aeruginosa carrying mutations in different trp genes. The plasmid pAJ24JI suppressed trpA, B and F mutants, pAJ73JI suppressed trpC and D and pAJ88JI suppressed a trpE mutant. When the R-primes were transferred to E. coli trp strains they failed to suppress any trp mutants. A derivative of pAJ24JI was isolated which was able to suppress trpA and F mutants of E. coli.
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38
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39
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Abstract
Various F' plasmids of Escherichia coli K-12 could be transferred into mutants of the soil strain 6.2, classified herein as a Pseudomonas fluorescens biotype IV. This strain was previously found to receive Flac plasmid (N. Datta and R.W. Hedges, J. Gen Microbiol. 70:453-460, 1972). ilv, leu, met, arg, and his auxotrophs were complemented by plasmids carrying isofunctional genes; trp mutants were not complemented or were very poorly complemented. The frequency of transfer was 10(-5). Subsequent transfer into other P. fluorescens recipients was of the same order of magnitude. Some transconjugants were unable to act as donors, and these did not lose the received information if subcultured on nonselective media. Use of F' plasmids helped to discriminate metabolic blocks in P. fluorescens. In particular, metA, metB, and argH mutants were so distinguished. In addition, F131 plasmid carrying the his operon and a supD mutation could partially relieve the auxotrophy of thr, ilv, and metA13 mutants, suggesting functional expression of E. coli tRNA in P. fluorescens. In P. fluorescens metA Rifr mutants carrying the F110 plasmid, which carried the E. coli metA gene and the E. coli rifs allele, sensitivity to rifampin was found to be dominant at least temporarily over resistance. This suggests interaction of E. coli and P. fluorescens subunits of RNA polymerase. his mutations were also complemented by composite P plasmids containing the his-nif region of Klebsiella pneumoniae (plasmids FN68 and RP41). nif expression could be detected by acetylene reduction in some his+ transconjugants. The frequency of transfer of these P plasmids was 5 X 10(-4).
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40
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Abstract
An R' plasmid, R'PA1, carrying a 3- to 4-min segment of the Pseudomonas aeruginosa chromosome has been derived from the incP-1 plasmid R68.45. The chromosomal segment includes the markers argA, argB, argH, and lys-12. The plasmid retains all the properties of R68.45, including chromosome mobilization ability and wide bacterial host range. R'PA1 reverts to R68.45 in rec+ strains of P. aeruginosa, but it can be maintained in a recA strain.
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41
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Haas D, Holloway BW. Chromosome mobilization by the R plasmid R68.45: a tool in Pseudomonas genetics. MOLECULAR & GENERAL GENETICS : MGG 1978; 158:229-37. [PMID: 415223 DOI: 10.1007/bf00267194] [Citation(s) in RCA: 109] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The conjugative plasmid R68.45 mobilizes the chromosome of Pseudomonas aeruginosa strain PAO from multiple sites located in different chromosome regions. In interrupted matings on the plate, selection for any single marker tested resulted in entry times of 3-5 min. When selection was imposed for two markers linked in R68.45-mediated conjugation, double recombinants appeared after a delay which corresponded approximately to the map distance between the two markers as measured by the sex factor FP2. Thus, R68.45 and FP2 appear to promote chromosome transfer at similar rates, but R68.45, unlike FP2, seems to give non-polarized transfer. R68.45 may be used to estimate map distances between linked markers located in those chromosome regions where other sex factors do not produce enough recombinants to permit accurate measurement of entry times. In R68.45 matings on the plate, most recombinants inherited short donor chromosome fragments (usually less than 10 min long) and lost the R plasmid during purification. Used like a "large" generalized transducing phage, R68.45 has proved valuable in construction of PAO strains with desired genotypes.
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42
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Dommergues YR, Belser LW, Schmidt EL. Limiting Factors for Microbial Growth and Activity in Soil. ADVANCES IN MICROBIAL ECOLOGY 1978. [DOI: 10.1007/978-1-4615-8222-9_2] [Citation(s) in RCA: 38] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
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43
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44
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Hedges R, Jacob A. In vivo translocation of genes ofPseudomonas aeruginosaonto a promiscuously transmissible plasmid. FEMS Microbiol Lett 1977. [DOI: 10.1111/j.1574-6968.1977.tb00898.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
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45
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46
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Hedges RW, Jacob AE, Crawford IP. Wide ranging plasmid bearing the Pseudomonas aeruginosa tryptophan synthase genes. Nature 1977; 267:283-4. [PMID: 405620 DOI: 10.1038/267283a0] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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47
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Johnston AW, Beringer JE. Genetic hydridization of root-nodule bacteria (Rhizobium). BASIC LIFE SCIENCES 1977; 9:81-90. [PMID: 921702 DOI: 10.1007/978-1-4684-0880-5_7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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