Plasmid transformation of naturally competent Acinetobacter calcoaceticus in non-sterile soil extract and groundwater

1992 ◽  
Vol 157 (4) ◽  
pp. 355-360 ◽  
Author(s):  
Michael G. Lorenz ◽  
Karin Reipschl�ger ◽  
Wilfried Wackernagel
Keyword(s):  
Acinetobacter Calcoaceticus ◽  
Soil Extract ◽  
Sterile Soil ◽  
Plasmid Transformation

Viability of an ectomycorrhizal inoculum produced in a liquid medium and entrapped in a calcium alginate gel

1987 ◽  
Vol 65 (11) ◽  
pp. 2326-2329 ◽  
Author(s):  
Ch. Mauperin ◽  
F. Mortier ◽  
J. Garbaye ◽  
F. Le Tacon ◽  
G. Carr
Keyword(s):  
Liquid Medium ◽  
Calcium Alginate ◽  
Storage Time ◽  
Storage Conditions ◽  
Soil Extract ◽  
Sterile Soil ◽  
Soil Extracts ◽  
Alginate Gel ◽  
Calcium Alginate Gel ◽  
Soil Hyphae

Survival of Hebeloma crustuliniforme (Bulliard ex Fries) Quelet, grown in a liquid medium and subsequently entrapped in beads of calcium alginate, was tested under different conditions. Mycelium viability was not affected either by curing the beads for up to 22 h in 0.7 M CaCl2 or by the addition of either peat or bentonite to the alginate gel. Both peat and bentonite improved the water retention of the alginate gel, but only the incorporation of bentonite slowed down the rate at which moisture was lost by evaporation. At 4 °C the entrapped mycelium retained its viability for at least 5 months, provided that storage conditions remained humid. Partial drying of the beads reduced the effective storage time to a month. Emergence of hyphae from the beads was influenced by the presence of sterile soil extracts prepared from a podzolic soil, an acid brown earth, a mesotrophic brown earth, an eutrophic brown earth, and a rendzina. Hyphae grew out of all the beads containing peat irrespective of the type of soil extract but only grew out of those containing bentonite when they were on the mesotrophic brown earth extract. Hyphal emergence from beads containing neither peat nor bentonite appeared to be influenced by the pH of the extract, being better on those that were more acidic. Both sterile and nonsterile nursery soil supported growth of hyphae from the three types of bead, but on nonsterile soil, hyphae were not abundant and those that developed began to die off sooner than those on sterile soil.

FACTORS INFLUENCING THE SURVIVAL AND ACTIVITY OF A PENTACHLOROPHENOL-DEGRADING Flavobacterium sp. IN SOIL SLURRIES

1990 ◽  
Vol 70 (1) ◽  
pp. 83-91 ◽  
Author(s):  
EDWARD TOPP ◽  
RICHARD S. HANSON
Keyword(s):  
Key Words ◽  
Soil Type ◽  
Soil Extract ◽  
Silt Loam ◽  
Clay Loam ◽  
Sterile Soil ◽  
Indigenous Bacteria ◽  
Colony Type ◽  
Factors Influencing ◽  
Copper Chromate

The effects of soil type, supplementation with carbon or inorganic nutrients, creosote, and copper/chromate/arsenate (CCA) mixtures, on viability and pentachlorophenol (PCP) degradation by inoculants of a PCP-degrading Flavobacterium sp. were examined in phosphate-buffered soil slurries. Populations of 108Flavobacterium/mL in non-sterile slurries prepared with clay loam, silt loam, or loamy sand declined by at least 95% within 3 d. Populations were stable for at least a week in heat-sterilized clay loam slurries but addition of non-sterile soil resulted in rapid death of the Flavobacterium sp. Supplementation with 4 g L−1 Na-glutamate or glucose, promoted the growth of the Flavobacterium sp. in non-sterile clay loam slurries. Supplementation with 1 g L−1 Na-glutamate, glucose, or p-hydroxybenzoate stimulated PCP degradation when the Flavobacterium sp. was inoculated at ≥ 108 cells mL−1 and the PCP concentration was less than 150 mg L−1. Addition of [Formula: see text], [Formula: see text], Mg2+, and Fe2+ together did not stimulate growth. Populations of culturable indigenous bacteria were larger in soil containing 50–300 mg L−1 PCP than in controls. Addition of PCP favored the predominance of one colony type identified as a pseudomonad. Creosote of CCA mixtures, pollutants often found together with PCP contamination, were inhibitory to the Flavobacterium sp. in soil extract. Key words: Pentachlorophenol, biodegradation, Flavobacterium, soil slurries

scholarly journals Influence of Soil Components on the Biodegradation of Benzene, Toluene, Ethylbenzene, and o-, m-, and p-Xylenes by the Newly Isolated Bacterium Pseudoxanthomonas spadix BD-a59

2008 ◽  
Vol 74 (23) ◽  
pp. 7313-7320 ◽  
Author(s):  
Jeong Myeong Kim ◽  
Ngoc Thuan Le ◽  
Bok Sil Chung ◽  
Jin Ho Park ◽  
Jin-Woo Bae ◽  
...  
Keyword(s):  
Yeast Extract ◽  
Soil Extract ◽  
Contaminated Sites ◽  
Enhancement Effect ◽  
Contaminated Sediment ◽  
Sterile Soil ◽  
Gasoline Station ◽  
Benzene Toluene ◽  
Soil Components ◽  
Btex Compounds

ABSTRACT A bacterium designated strain BD-a59, able to degrade all six benzene, toluene, ethylbenzene, and o-, m-, and p-xylene (BTEX) compounds, was isolated by plating gasoline-contaminated sediment from a gasoline station in Geoje, Republic of Korea, without enrichment, on minimal salts basal (MSB) agar containing 0.01% yeast extract, with BTEX as the sole carbon and energy source. Taxonomic analyses showed that the isolate belonged to Pseudoxanthomonas spadix, and until now, the genus Pseudoxanthomonas has not included any known BTEX degraders. The BTEX biodegradation rate was very low in MSB broth, but adding a small amount of yeast extract greatly enhanced the biodegradation. Interestingly, degradation occurred very quickly in slurry systems amended with sterile soil solids but not with aqueous soil extract. Moreover, if soil was combusted first to remove organic matter, the enhancement effect on BTEX biodegradation was lost, indicating that some components of insoluble organic compounds are nutritionally beneficial for BTEX degradation. Reverse transcriptase PCR-based analysis of field-fixed mRNA revealed expression of the tmoA gene, whose sequence was closely related to that carried by strain BD-a59. This study suggests that strain BD-a59 has the potential to assist in BTEX biodegradation at contaminated sites.

scholarly journals The filamentous bacteria Sphaerotilus, Leptothrix, Cladothrix , and their relation to iron and manganese

1949 ◽  
Vol 233 (605) ◽  
pp. 453-482 ◽  
Keyword(s):  
Related Species ◽  
Manganese Oxides ◽  
Soil Extract ◽  
Filamentous Bacteria ◽  
Sterile Soil ◽  
Meat Extract ◽  
Sphaerotilus Natans ◽  
Cultural Conditions ◽  
Microscopic Inspection ◽  
Iron And Manganese

The Chlamydobacteriaceae are a family of filamentous bacteria varying extremely with environmental conditions. The tacit assumption that species can be distinguished by mere microscopic inspection has led to the creation of numerous genera, species, and varieties of doubtful validity. In order to detect reversible modifications and hereditary differences cultures were undertaken. Threads of Sphaerotilus natans, Cladothrix dichotoma and Leptothrix ochracea were washed in sterile soil extract and transferred to agar plates with a low concentration of meat extract. By repeated plating several strains of each form were obtained in pure culture. All of these were identical, despite their origin from the various ‘species’ mentioned. By modifying the cultural conditions each strain could be made to change into the three original forms, as well as into certain others generally believed to belong to distinct genera. Since Sphaerotilus natans Kütz. is the oldest name it must be retained for all these forms. Schwers’s Megalothrix discophora , which was later referred to other genera and has been grown in culture by various authors, was not obtained from the cultures of Sphaerotilus natans . It represents a second related species of Sphaerotilus which may be named S. discophorus . Further species of Sphaerotilus have been described under the name of Leptothrix , but of the remaining socalled genera of the Chlamydobacteriaceae Crenothrix alone seems to be well founded. Conclusions are also reached on the colour of iron-containing deposits. If these appear brown, it is due to admixture of manganese oxides. Otherwise the colour is only slightly yellowish under the microscope and orange-ochre in larger accumulations. The envelopes produced by various organisms may contain much iron without its presence being revealed by their colour, although it can be recognized by the very refractive and brittle character of the envelopes and by micro-chemical reactions.

scholarly journals Bleeding Canker on Mesquite in Peru caused by Phytophthora syringae

Plant Disease ◽  
2007 ◽  
Vol 91 (2) ◽  
pp. 226-226
Author(s):  
L. A. Álvarez ◽  
A. Pérez-Sierra ◽  
J. García-Jiménez ◽  
J. Javier-Alva
Keyword(s):  
Growth Rate ◽  
Soil Extract ◽  
Phytophthora Species ◽  
Fluorescent Light ◽  
Width Ratio ◽  
Citrus Limon ◽  
Sterile Soil ◽  
Agar Culture ◽  
Root Rots ◽  
Pure Cultures

Mesquite (Prosopis pallida (Wildenow) Kunth) is a drought-tolerant tree widely distributed in the northern Pacific Coast of South America. This species prevents soil erosion, provides shade, conserves prairies, supports bee nutrition, and provides fruits for human and animal consumption. Since the spring of 2004, bark lesions and bleeding cankers were observed on trunks and branches of 70% of declining mesquite trees in some parks at Ica in southern Peru. Badly affected trees were killed by the disease. Isolations were made from the edge of necrotic lesions of the inner bark and roots using PARPH medium (2) and incubated at 22°C for 7 days. A Phytophthora species was consistently isolated from lesions of 10 mesquite trees, and six pure cultures (PS-87-PS-92) were obtained by transferring hyphal tips and characterized. Colonies were stellate on V8 juice agar (VJA; 2 g CaCO3, 200 ml of V8 juice, and 15 g of agar in 800 ml of distilled water), uniform to slightly radiate on corn meal agar (Oxoid Ltd., London, England), and knotty on PDA (Biokar Diagnostics, Beauvais, France). On VJA at 22°C, the average radial growth rate for the six isolates was 1.7 mm per day. Colonies grew slowly at 5 and 25°C with 0.4 and 0.7 mm per day growth rate, respectively. There was no growth at 30°C. Catenulate hyphal swellings formed on VJA and liquid media (1.5% sterile soil extract). Sporangia were persistent, ovoid to obpyriform, semipapillate with narrow exit pores (<5.0 μm in diameter), 32.3 to 39.7 × 21.0 to 27.2 μm, with a length/width ratio of 1.4:1 to 1.6:1. Sporangia were produced by cutting 5-mm disks from the advancing margin of a colony on VJA and adding disks to 10 ml of 1.5% sterile soil extract for 4 to 5 days at 22°C under fluorescent light. Isolates were homothallic with spherical oogonia, 32 to 35 μm in width with paragynous antheridia, and aplerotic oospores, 26 to 31 μm. These characteristics fit the descriptions of Phytophthora syringae (Kleb.) Kleb. (1). Sequences of the internal transcribed spacer regions on the isolates and comparison with other sequences in GenBank showed that they were identical to P. syringae (Accession No. AJ854297 from Citrus limon). In 2005, two methods were used to inoculate mesquite with two isolates. One method used two 20-mm-diameter branches of five 5-year-old mesquite trees where a 5-mm wound was made with a cork borer and a 5-mm block of the agar culture was placed under the bark and sealed with Parafilm. Another method used 10 4-month-old potted plants that received a 30-ml drench of a 104 zoospores/ml suspension per plant. Controls received clean agar blocks and a sterile water drench for 10 control pots. Two weeks after inoculation, black areas and resinosis were observed around inoculated wounds. Inoculated branches produced cankers of 4.7 to 6.8 cm2, 4 weeks after inoculations. Twenty days after inoculation of roots, wilting and root rots of seedlings occurred. No symptoms were found on the control plants. P. syringae was reisolated from the diseased branches and root rots and pure cultures were established. This test was repeated for both methods with similar results. To our knowledge, this is the first report of P. syringae in Peru and the first description of this pathogen on mesquite worldwide. References: (1) D. C. Erwin and O. K. Ribeiro. Phytophthora Diseases Worldwide. The American Phytopathological Society, St. Paul MN. 1996. (2) S. N. Jeffers and S. B. Martin. Plant Dis. 70:1038, 1986.

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