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1.
Mycorrhiza ; 17(3): 159-166, 2007 May.
Article in English | MEDLINE | ID: mdl-17143615

ABSTRACT

Pterocarpus officinalis (Jacq.) seedlings inoculated with the arbuscular mycorrhizal fungus, Glomus intraradices, and the strain of Bradyrhizobium sp. (UAG 11A) were grown under stem-flooded or nonflooded conditions for 13 weeks after 4 weeks of nonflooded pretreatment under greenhouse conditions. Flooding of P. officinalis seedlings induced several morphological and physiological adaptive mechanisms, including formation of hypertrophied lenticels and aerenchyma tissue and production of adventitious roots on submerged portions of the stem. Flooding also resulted in an increase in collar diameter and leaf, stem, root, and total dry weights, regardless of inoculation. Under flooding, arbuscular mycorrhizas were well developed on root systems and adventitious roots compared with inoculated root systems under nonflooding condition. Arbuscular mycorrhizas made noteworthy contributions to the flood tolerance of P. officinalis seedlings by improving plant growth and P acquisition in leaves. We report in this study the novel occurrence of nodules connected vascularly to the stem and nodule and arbuscular mycorrhizas on adventitious roots of P. officinalis seedlings. Root nodules appeared more efficient fixing N(2) than stem nodules were. Beneficial effect of nodulation in terms of total dry weight and N acquisition in leaves was particularly noted in seedlings growing under flooding conditions. There was no additive effect of arbuscular mycorrhizas and nodulation on plant growth and nutrition in either flooding treatment. The results suggest that the development of adventitious roots, aerenchyma tissue, and hypertrophied lenticels may play a major role in flooded tolerance of P. officinalis symbiosis by increasing oxygen diffusion to the submerged part of the stem and root zone, and therefore contribute to plant growth and nutrition.


Subject(s)
Mycorrhizae/growth & development , Pterocarpus/microbiology , Acclimatization , Bradyrhizobium/growth & development , Bradyrhizobium/physiology , Disasters , Mycorrhizae/physiology , Nitrogen Fixation , Pterocarpus/growth & development , Pterocarpus/physiology , Seedlings/growth & development , Seedlings/microbiology , Seedlings/physiology , Symbiosis
2.
Mycorrhiza ; 16(8): 559-565, 2006 Nov.
Article in English | MEDLINE | ID: mdl-17033816

ABSTRACT

The purpose of this study was to test the capacity of the ectomycorrhizal (ECM) fungus, Scleroderma bermudense, to alleviate saline stress in seagrape (Coccoloba uvifera L.) seedlings. Plants were grown over a range (0, 200, 350 and 500 mM) of NaCl levels for 12 weeks, after 4 weeks of non-saline pre-treatment under greenhouse conditions. Growth and mineral nutrition of the seagrape seedlings were stimulated by S. bermudense regardless of salt stress. Although ECM colonization was reduced with increasing NaCl levels, ECM dependency of seagrape seedlings increased. Tissues of ECM plants had significantly increased concentrations of P and K but lower Na and Cl concentrations than those of non-ECM plants. Higher K concentrations in the leaves of ECM plants suggested a higher osmoregulating capacity of these plants. Moreover, the water status of ECM plants was improved despite their higher evaporative leaf surface. The results suggest that the reduction in Na and Cl uptake together with a concomitant increase in P and K absorption and a higher water status in ECM plants may be important salt-alleviating mechanisms for seagrape seedlings growing in saline soils.


Subject(s)
Mycorrhizae/metabolism , Polygonaceae/drug effects , Polygonaceae/microbiology , Sodium Chloride/pharmacology , Dose-Response Relationship, Drug , Plant Leaves/drug effects , Plant Leaves/growth & development , Plant Leaves/microbiology , Plant Roots/drug effects , Plant Roots/growth & development , Plant Roots/microbiology , Plant Shoots/drug effects , Plant Shoots/growth & development , Plant Shoots/microbiology , Polygonaceae/metabolism , Seedlings/drug effects , Seedlings/metabolism , Seedlings/microbiology
3.
Mycorrhiza ; 16(1): 11-17, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16007470

ABSTRACT

Five caesalpinioid legumes, Afzelia africana, Afzelia bella, Anthonotha macrophylla, Cryptosepalum tetraphylum and Paramacrolobium coeruleum, and one Euphorbiaceae species, Uapaca somon, with a considerable range in seed sizes, exhibited different responses to inoculation by four species of ectomycorrhizal (ECM) fungi, Scleroderma dictyosporum, S. verrucosum, Pisolithus sp. and one thelephoroid sp. in greenhouse conditions. Thelephoroid sp. efficiently colonized seedlings of all of the five caesalpinioid legumes except U. somon, but provided no more growth benefit than the other fungi. Thelephoroid sp. and S. dictyosporum colonized seedlings of U. somon poorly, but stimulated plant growth more than the other fungi. The relative mycorrhizal dependency (RMD) values of the caesalpinioid legumes were never higher than 50%, whilst U. somon had RMD values ranging from 84.6 to 88.6%, irrespective of the fungal species. The RMD values were negatively related to seed mass for all plant species. Potassium concentrations in leaves were more closely related than phosphorus to the stimulation of seedling biomass production by the ECM fungi. Our data support the hypothesis that African caesalpinioid legumes and euphorbe tree species with smaller seeds show higher RMD values than those with the larger seeds.


Subject(s)
Basidiomycota/growth & development , Fabaceae/growth & development , Mycorrhizae/growth & development , Seedlings/growth & development , Trees/growth & development , Trees/microbiology , Biomass , Fabaceae/microbiology , Phosphorus/analysis , Plant Leaves/chemistry , Potassium/analysis , Seedlings/microbiology , Seeds/growth & development , Statistics as Topic
4.
Mycorrhiza ; 14(5): 313-22, 2004 Oct.
Article in English | MEDLINE | ID: mdl-14634857

ABSTRACT

This study was conducted to evaluate the competitiveness and effectiveness of Thelephoroid fungal sp. ORS.XM002 against native ectomycorrhizal fungal species colonizing potted Afzelia africana seedlings during 3 months of growth in different forest soils collected from under mature trees. Using morphotyping and restriction fragment length polymorphism (RFLP) analysis of the nuclear rDNA internal transcribed spacer (ITS), we were able to distinguish the introduced Thelephoroid fungal sp. ORS.XM002 among native ectomycorrhizal fungal species that form ectomycorrhizae in A. africana seedlings. The morphotype (MT) of the introduced fungus showed some color variation, with a shift from light- to dark-brown observed from younger to older mycorrhizal tips. We were able to differentiate the ITS type xm002 of the introduced fungus from the 14 ITS-RFLP types characterizing the 9 native MT that occurred in forest soils. The frequency of ITS type xm002 ranged from 40% to 49% depending on the forest soil used, and was always higher than those of ITS types from native dark-brown MT that occurred in inoculated seedlings 3 months after inoculation. We considered Thelephoroid fungal sp. ORS.XM002 to be responsible for stimulation of mycorrhizal colonization of inoculated A. africana seedlings when compared with control seedlings in forest soils. This fungus appeared to be more effective in increasing the root dry weight of A. africana seedlings. To identify the unknown introduced fungal species and native MT, we sequenced the ML5/ML6 region of the mitochondrial large subunit rRNA. Sequence analysis showed that these fungi belong to three ML5/ML6 groups closely related to the Cortinarioid, Thelephoroid, and Sclerodermataceous taxa. The molecular evidence for the persistence of Thelephoroid fungal sp. ORS.XM002 despite competition from native fungi argues in favor of using this fungus with A. africana in nursery soil conditions in Senegal.


Subject(s)
Fabaceae/microbiology , Mycorrhizae/physiology , Trees/microbiology , Basidiomycota/physiology , DNA, Fungal/genetics , Fabaceae/growth & development , Phylogeny , Plant Roots/microbiology , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , Seedlings/growth & development , Seedlings/microbiology , Senegal , Soil Microbiology , Trees/growth & development
5.
Mol Gen Mikrobiol Virusol ; (1): 22-5, 1997.
Article in Russian | MEDLINE | ID: mdl-9082183

ABSTRACT

Fourteen out of fifty-two examined strains of Aeromonas contain plasmids. One of them determines the resistance to tetracycline, streptomycin, and chloramphenicol. The pAs30 plasmid, 53 t. n. p. in size, is capable of conjugative transfer to bacteria of different genera, which permits us to consider it a broad host range plasmid. Using 12 restriction endonucleases, the physical map of the plasmid was plotted, on which the genes responsible for transporting functions and streptomycin resistance were tentatively located.


Subject(s)
Aeromonas/genetics , Drug Resistance, Microbial/genetics , Plasmids
6.
J Biomol Struct Dyn ; 12(2): 355-66, 1994 Oct.
Article in English | MEDLINE | ID: mdl-7702774

ABSTRACT

The theoretical approach to the calculation of the influence of selective binding of small ligands on DNA helix-coil transition has been described in the previous paper (Lando D. Yu., J. Biomol. Struct. Dyn., (1994)). In the present paper that method is used for the study of DNA protonation and deprotonation in acidic and alkaline medium by theoretical analysis of pH effect on DNA heat denaturation. The mechanism of DNA protonation in acidic medium and pK values of nucleotides are well known. It gave us an opportunity to check the theory without any fitting of pK values. A good agreement between experimental and calculated functions Tm(pH) and delta T(pH) (melting temperature and melting range width) obtained for acidic medium proved the validity of the theory. However, for alkaline medium there was not even qualitative agreement when the agreed-upon mechanism of deprotonation was considered. Looking into the cause of the discrepancy, we have studied the DNA melting for different mechanisms of deprotonation by calculation of Tm(pH) and delta T(pH). As a result, it has been established that the discrepancy is due to deprotonation of bonded GC base pairs of helical DNA regions (pK = 11). It was shown that the early known protonation and newly found deprotonation of helical DNA essentially stabilised double helix in alkaline and acidic medium.


Subject(s)
DNA, Bacterial/chemistry , DNA/chemistry , Models, Theoretical , Nucleic Acid Conformation , Animals , Cattle , Hydrogen-Ion Concentration , Kinetics , Ligands , Mathematics , Thermodynamics , Thymus Gland
7.
Mol Gen Mikrobiol Virusol ; (12): 26-9, 1991 Dec.
Article in Russian | MEDLINE | ID: mdl-1787841

ABSTRACT

The recombinant bacteriophages with the genomes containing the DNA fragments of bacteria Erwinia chrysanthemi, including the pectatelyase gene, were constructed on the base of Pseudomonas aeruginosa temperate bacteriophage SM. The gene transferred into Pseudomonas aeruginosa PAO1 cells by transfection is expressed in the new bacterial host. The restriction maps of the recombinant bacteriophages are constructed and the position of an insert is defined. Bacteriophage SM was found to be capable of reproducing in Pseudomonas aeruginosa PAO1 cells when its DNA was shortened to 88% or increased to 111% of the normal genome length. Except for bacteriophage SM, the recombinant bacteriophage SM-2 with an unique restriction endonuclease site for XbaI can also be used as a vector for cloning. Bacteriophage SM capacity in cloning of heterological DNA at HindIII sites is not less than 8 Md, capacity of bacteriophage SM-2 is not less than 5 and 8 Md at XbaI and HindIII sites respectively.


Subject(s)
Bacteriophages/genetics , Pseudomonas aeruginosa/genetics , Cloning, Molecular , DNA, Bacterial/genetics , Dickeya chrysanthemi/genetics , Gene Expression , Genes, Bacterial , Genes, Viral , Genetic Vectors , Restriction Mapping , Transfection
8.
New Phytol ; 114(1): 99-103, 1990 Jan.
Article in English | MEDLINE | ID: mdl-33874289

ABSTRACT

Afzelia-associated fungi in Senegal were isolated from sporocarps, sclerotia and ectomycorrhizas. The choice of sterilizing agent was critical for the success of isolation. Osmic acid was more efficient than mercuric chloride, hydrogen peroxide and calcium hypochlorite. Isolates were tested for their ability to form mycorrhizas in vitro and their mycelia in pure culture were described. Sclerotia linked to mycorrhizas of Scleraderma verrucosum Pers. were also isolated and their infectivity checked. Among isolates from sporocarps, only Scleroderma dictvosparum Fat. and S. verrucosum Pers. formed ectomycorrhizas with Afzelia africana Sm. Two native Amanita spp. and two introduced isolates belonging to the genus Pisolithus did not form typical ectomycorrhizas although a normal mantle was observed.

9.
Mol Gen Mikrobiol Virusol ; (1): 25-9, 1988 Jan.
Article in Russian | MEDLINE | ID: mdl-3128732

ABSTRACT

Pseudomonas aeruginosa PAO SM-prophage was localized on the chromosome between thr-9001 and pur-66 locuses on 42-43 min of chromosomal genetic map. The location of prophage was identified on the basis of prophage linkage with the above-mentioned markers and confirmed by the purine, hypoxanthine and threonine deletions in course of thermoinduction of SM cts6 prophage from lysogens. The decrease for two orders in lysogenization frequency of thr mutants by SM bacteriophage suggests the integration of SM prophage in these cells into some other region of chromosome.


Subject(s)
Bacteriophages/genetics , Chromosomes, Bacterial , Lysogeny , Genetic Markers , Mutation , Pseudomonas aeruginosa/genetics
10.
Mol Biol (Mosk) ; 20(1): 181-4, 1986.
Article in Russian | MEDLINE | ID: mdl-3005840

ABSTRACT

The DNA of temperate phage SM P. aeruginosa has one PvuII site, two BamHI sites, three HindIII sites and five EcoRI sites. Using these restrictases the physical map of the phage genome has been constructed. The DNA of phage SM has in their structure cohesive ends similar to cos-sites of phage lambda DNA. EcoRI-fragments with cohesive ends have molecular masses 2.9 and 4.9 MDa.


Subject(s)
Bacteriophages/genetics , DNA, Viral/genetics , Bacteriophages/analysis , Chromosome Mapping , DNA Restriction Enzymes , DNA, Viral/analysis , Genetic Markers , Molecular Weight , Pseudomonas aeruginosa
11.
Genetika ; 21(11): 1782-6, 1985 Nov.
Article in Russian | MEDLINE | ID: mdl-3935514

ABSTRACT

76 mutants with impaired ability to lysogenize host cells were isolated in SM phage after mutagenesis using several chemical mutagens. By means of complementation test, these mutants were distributed into two groups, cI and cII. The mutants of the cI group were similar phenotypically to the cI mutants of phage lambda defective in synthesis of repressor. The mutants of the cII group establish and support the lysogenic state in infected cells with very low frequency. Temperature-sensitive mutants belonging to 13 complementation groups and nonlysogenizing mutants of the cI and cII groups were used in genetic mapping of SM phage. Mutual positions of markers and relative distances between them were determined by the method of two-factorial crosses. The greatest distance equal to 20 units of recombination was determined between ts 88 marker and one of early genes marked with ts 105 mutation. The genes cI and cII are closely linked to each other and also to ts 105 marker and are situated at one end of the genetic map.


Subject(s)
Bacteriophages/genetics , Genes, Viral , Lysogeny , Chromosome Mapping , Mutation , Pseudomonas aeruginosa , Recombination, Genetic
12.
Genetika ; 21(11): 1787-93, 1985 Nov.
Article in Russian | MEDLINE | ID: mdl-3000870

ABSTRACT

Based on the data of stability of the donor state of Hfr-like strain Erwinia chrysanthemi VY1-10 in RecA+ and RecA- cells, it can be suggested that the donor properties of the strain are mediated by the presence of the genetic homology region which occurred as a result of transposition of the Tn1000 from the Flac+ plasmid into the chromosome of E. chrysanthemi. Tn1000 may be transposed into several sites on the chromosome of E. chrysanthemi ENA49. This leads to the appearance of donors transferring their chromosome from several fixed points oriT and in opposite directions. The location of these points and the direction of transfer are determined by Tn1000 insertion sites and their orientation.


Subject(s)
Chromosomes, Bacterial , Conjugation, Genetic , DNA Transposable Elements , Erwinia/genetics , Plasmids , Cloning, Molecular
13.
Mol Gen Mikrobiol Virusol ; (9): 3-6, 1985 Sep.
Article in Russian | MEDLINE | ID: mdl-3939575

ABSTRACT

The inheritance of plasmids Rms163 and R74 by Pseudomonas aeruginosa strain PAO hs been shown to effect the reproduction of a temperature bacteriophage SM. The decrease in plating efficiency of bacteriophage on Pseudomonas aeruginosa PAO (rms163) lawn is explained by the high degree of cell lysogenization by bacteriophage. Plasmid R74 inhibits bacteriophage SM propagation ultimately, evidently due to interruption of definite stages in vegetative development of bacteriophage by the products of plasmid specific genes.


Subject(s)
Bacteriophages/genetics , R Factors , Virus Replication , Bacteriophages/physiology , Lysogeny , Pseudomonas aeruginosa/genetics
14.
Genetika ; 21(4): 548-55, 1985 Apr.
Article in Russian | MEDLINE | ID: mdl-3924729

ABSTRACT

Seventy three temperature-sensitive mutants of Pseudomonas aeruginosa SM phage have been obtained using different mutagens and assigned to thirteen complementation groups. Representative mutants of each group have been studied with the aim of characterizing tentatively the time of genes expression in infected bacteria. Two genes appear to function during the first minutes after infection, whereas the remaining genes are needed for late functions. Most of the temperature-sensitive functions in the different mutants are reversible, i.e. they become active when the infected cells are shifted-down to the permissive temperature.


Subject(s)
Bacteriophages/genetics , Genetic Complementation Test , Mutation , Bacteriolysis , Bacteriophages/physiology , Gene Expression Regulation , Genes, Viral , Lysogeny , Pseudomonas aeruginosa , Temperature , Time Factors , Virus Activation
15.
Mol Gen Mikrobiol Virusol ; (1): 22-5, 1985 Jan.
Article in Russian | MEDLINE | ID: mdl-3025675

ABSTRACT

50 Md conjugative plasmid, designated pM3, has been found in the cells from natural isolates of Pseudomonas sp M. The plasmid determines the resistance to tetracycline and streptomycin and is capable of conjugative transfer between the cells of Pseudomonas and Escherichia coli. The conjugative derivatives of pM3 deleted for 14 Md of molecular mass were isolated after acridine dyes treatment of cells harbouring plasmid pM3. The discovered plasmid was not shown to belong to IncP1 incompatibility group.


Subject(s)
Conjugation, Genetic , Pseudomonas/genetics , R Factors , DNA Restriction Enzymes , Methanol/metabolism , Pseudomonas/metabolism
16.
Genetika ; 20(1): 185-6, 1984 Jan.
Article in Russian | MEDLINE | ID: mdl-6421656

ABSTRACT

The temperate bacteriophage SM is not serologically related to the known transducing phages F116, G101, B3 of Pseudomonas aeruginosa. The strains with auxotrophic mutations within the wide ranges of the genetic map of P. aeruginosa strain PAO1 were used for studying the transducing activity of the SM phage. All of the 7 bacterial markers tested are transduced with SM phage grown on a prototrophic donor strain. The frequency of transduction of separate bacterial markers using the wild type SM phage is 2.3 to 4.6 X 10(-8). Linked ilv202+ - met28+ markers are cotransduced with SM phage at a frequency of about 1.5%.


Subject(s)
Bacteriophages/genetics , Transduction, Genetic , Genetic Markers , Pseudomonas aeruginosa
18.
Mol Biol (Mosk) ; 17(5): 1108-11, 1983.
Article in Russian | MEDLINE | ID: mdl-6633530

ABSTRACT

Base ratio of DNA from 21 bacteriophage of Pseudomonas was determined by chemical hydrolysis and paper chromatography. Obtained values of the GC pair content were compared with melting temperature of DNA in 0,1 X SSC. The content of GC pairs correlates with melting temperature by equation %GC = 2,53 (Tm - 53,4). The content of GC pair for DNA from 30 bacteriophages of Pseudomonas was calculated. Some speculations concerning the distribution in DNA base ratio of bacteriophages of Pseudomonas are discussed.


Subject(s)
Bacteriophages/genetics , DNA, Viral/analysis , Pseudomonas/genetics , Base Composition , Nucleic Acid Denaturation , Osmolar Concentration , Solvents , Species Specificity
19.
Mol Biol (Mosk) ; 15(5): 1093-1101, 1981.
Article in Russian | MEDLINE | ID: mdl-7300828

ABSTRACT

The DNA thermal denaturation in acidic medium has been investigated experimentally and theoretically. The formulae describing a dependence of the helix--coil transition parameters (melting temperature (Tm) and melting range width (delta T) on ionisation constants values of all kinds of DNA bases in the helix and coil regions and medium acidity have been obtained. Dependences Tm (pH) and delta T (pH) have been determined experimentally and calculated for different models of protonation. Based on the comparison of theoretical and experimental dependences Tm (pH) and delta T (pH) a strict examination of the theory is conducted. The mechanism of DNA protonation is discussed.


Subject(s)
DNA , Nucleic Acid Denaturation , Animals , Cattle , Chemical Phenomena , Chemistry , DNA/isolation & purification , Hot Temperature , Hydrogen-Ion Concentration , Ligands , Mathematics , Models, Chemical , Thymus Gland/analysis
20.
Biofizika ; 26(3): 389-93, 1981.
Article in Russian | MEDLINE | ID: mdl-7260148

ABSTRACT

Using gel-filtration and spectral-luminescent analysis properties of artificial chlorophyll-protein and chlorine-protein complexes on the basis of human serum albumin (HSA) were analysed. It has been shown that formation of joint complexes pigments - HSA does not induce essential changes in the spectral and energetic parameters of the pigment part of the complex. A change in the rate of photosensitized reduction of methylviologen (sensitizer-pigment) was found during the variation of the relative content of the pigment mixed with HSA. An increase of the photoreaction rate during maximal filling of the protein globule with pigment molecules is explained by different pattern of incorporation of these molecules into protein matrix.


Subject(s)
Pigments, Biological , Serum Albumin , Chlorophyll , Humans , Kinetics , Photochemistry , Protein Binding , Spectrophotometry
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