Characterization of a nitrogen-fixing bacterial strain from the roots of Digitaria sanguinalis

1976 ◽  
Vol 22 (2) ◽  
pp. 254-260 ◽  
Author(s):  
Lynn E. Barber ◽  
Harold J. Evans
Keyword(s):  
Nitrogen Fixation ◽  
Bacterial Strain ◽  
Optimal Growth ◽  
Root Systems ◽  
Mixed Cultures ◽  
Nitrogen Fixing ◽  
Digitaria Sanguinalis ◽  
Gram Negative ◽  
Root Sample

Rates of nitrogen fixation of 3 to 10 g of N2 fixed per hectare per day were associated with root systems of Digitaria sanguinalis. A Gram-negative motile aerobic bacterial strain that was capable of N2 fixation was isolated from a washed root sample of one of these plants. Optimal growth and N2 fixation occurred at a pH of about 6.5, a temperature of 30–37 °C, and at a pO2 of about 0.01 atm. Increased rates of N2 fixation resulted when this strain was grown in mixed cultures with aerobic or facultative bacteria. Observations of cellular and cultural morphology and results of biochemical and physiological studies indicate that the isolate may be related to the Azotobacteraceae but that it is not identical with any of the members of this family. The importance of N2 fixation by this isolate in nature is unknown.

Immunochemical characterization of lipopolysaccharide from glucose-nonfermenting gram-negative clinical bacterial isolate.

1997 ◽  
Vol 44 (2) ◽  
pp. 293-299 ◽  
Author(s):  
M Mieszała ◽  
J Kübler ◽  
A Gamian
Keyword(s):  
Fatty Acid Composition ◽  
Fatty Acid ◽  
Acid Composition ◽  
Bacterial Strain ◽  
Bacterial Isolate ◽  
Pulmonary Diseases ◽  
Gram Negative ◽  
Immunochemical Characterization ◽  
Phenol Water

A glucose-nonfermenting Gram-negative bacterial strain isolated from bronchofiberoscope used for examination of the patients suffering from pulmonary diseases was subjected to phenol-water extraction. Lipopolysaccharides (LPS) isolated from the water and the phenol phase differed in fatty acid composition. Both contained xylose, glucose, glucosamine and components typical for LPS, namely heptose, 3-deoxyoctulosonic acid (Kdo) and 3-hydroxymyristic acid. The presence of sphingosine in all LPS preparations classifies the strain to the genus Sphingomonas.

scholarly journals Description of Azospira restricta sp. nov., a nitrogen-fixing bacterium isolated from groundwater

2007 ◽  
Vol 57 (7) ◽  
pp. 1521-1526 ◽  
Author(s):  
Hee-Sung Bae ◽  
Brian A. Rash ◽  
Fred A. Rainey ◽  
M. Fernanda Nobre ◽  
Igor Tiago ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Bacterial Strain ◽  
Type Strain ◽  
Novel Species ◽  
Polyphasic Approach ◽  
Polar Flagellum ◽  
Nitrogen Fixing ◽  
Gram Negative ◽  
Storage Granules ◽  
Curved Rods

A novel, Gram-negative bacterial strain, SUA2T, isolated from groundwater, was characterized using a polyphasic approach. Cells are Gram-negative, non-spore-forming, straight to curved rods with a single polar flagellum. Strain SUA2T is oxidase- and catalase-positive and is able to fix nitrogen. Poly-β-hydroxybutyrate storage granules are produced. Dominant fatty acids when grown in R2A and VM ethanol media for 72 h at 37 °C are C16 : 0, C16 : 1 ω7c, C17 : 0 cyclo, C10 : 0 3-OH, C18 : 1 ω7c, C12 : 0 and C15 : 0. DNA G+C content is 67.9 mol%. Phenotypic and phylogenetic data indicate that strain SUA2T is related to, but clearly differentiated from Azospira oryzae. Strain SUA2T is thus proposed as a novel species of the genus Azospira with the name Azospira restricta sp. nov. The description of the genus Azospira is emended to include the characteristics of this novel species. The type strain of Azospira restricta is SUA2T (=NRRL B-41660T=DSM 18626T=LMG 23819T).

A new nitrogen-fixing Clostridium species from a high Arctic ecosystem

1979 ◽  
Vol 25 (8) ◽  
pp. 947-948 ◽  
Author(s):  
D. C. Jordan ◽  
Patricia J. McNicol
Keyword(s):  
Nitrogen Fixation ◽  
Nitrogenase Activity ◽  
High Arctic ◽  
Undescribed Species ◽  
Nitrogen Fixing ◽  
Canadian High Arctic ◽  
Clostridium Species ◽  
Gram Negative ◽  
Arctic Ecosystem ◽  
Devon Island

A hitherto undescribed species of yellow-pigmented, Gram-negative Clostridium sp., possessing nitrogenase activity, has been isolated from a number of sampling sites on the Truelove Lowland of Devon Island in the Canadian high Arctic. This bacterium, tentatively designated Clostridium arcticum sp. nov., accounted for 19% of all isolates recovered which were capable of anaerobic nitrogen fixation.

Nitrogen fixation by Rhizobium sp. 32H1. A morphological and ultrastructural comparison of asymbiotic and symbiotic nitrogen-fixing forms

1979 ◽  
Vol 25 (3) ◽  
pp. 352-361 ◽  
Author(s):  
A. A. N. Van Brussel ◽  
J. W. Costerton ◽  
J.J. Child
Keyword(s):  
Cell Wall ◽  
Nitrogen Fixation ◽  
Cytoplasmic Membrane ◽  
Cultured Cells ◽  
Morphological Changes ◽  
Gram Negative Bacteria ◽  
Nitrogen Fixing ◽  
Gram Negative ◽  
Freeze Etching ◽  
Rhizobium Sp

The induction of nitrogenase (C2H2) activity in asymbiotically cultured Rhizobium sp. 32H1 was found to be associated with morphological changes in the cells which were more pronounced than those seen in bacteroids. Polyphosphate granules were found in both bacteroids and cultured cells, but poly-β-hydroxybutyrate vesicles were almost absent in bacteroids but were present in cultured cells. Freeze-etching techniques revealed no differences between the asymbiotically cultured nitrogen-fixing forms and bacteroids in that both the cell wall and cytoplasmic membrane cleavage planes were normal for gram-negative bacteria.

scholarly journals Cardiobacterium hominis endocarditis: description of two patients and characterization of the organism

1977 ◽  
Vol 5 (1) ◽  
pp. 75-80
Author(s):  
D D Savage ◽  
R L Kagan ◽  
N A Young ◽  
A E Horvath
Keyword(s):  
Optimal Growth ◽  
Culture Collection ◽  
National Institutes Of Health ◽  
Bacteriological Response ◽  
Gram Negative ◽  
Sugar Fermentation ◽  
Slow Growing ◽  
Oxidase Reaction ◽  
Chronic Course

Two cases of endocarditis caused by Cardiobacterium hominis are reported. In both instances infection was subacute and characterized by (i) implantation on abnormal valves, (ii) chronic course lasting weeks to months before recognition, and (iii) rapid clinical and bacteriological response to penicillin, as well as other antibiotics commonly used to treat infections caused by gram-negative bacilli. Our isolates of C. hominis are compared with strains in the National Institutes of Health culture collection. Optimal growth requires yeast extract and incubation at 37 degrees C with increased humidity and supplemental CO2. The production of indole, a positive oxidase reaction, and characteristic sugar fermentation distinguish C. hominis from other slow-growing, gram-negative bacilli.

Application of commercial test-systems to identify gram-negative facultatively anaerobic bacteria

2016 ◽  
Vol 3 (1) ◽  
pp. 43-48 ◽  
Author(s):  
V. Patyka ◽  
L. Butsenko ◽  
L. Pasichnyk
Keyword(s):  
Erwinia Amylovora ◽  
Anaerobic Bacteria ◽  
Biochemical Properties ◽  
Test System ◽  
Phytopathogenic Bacteria ◽  
Gram Negative ◽  
Test Systems ◽  
Facultatively Anaerobic ◽  
Microbiological Methods

Aim. To validate the suitability of commercial API 20E test-system (bioMerieux) for the identifi cation and characterization of facultative gram-negative phytopathogenic bacterial isolates. Methods. Conventional mi- crobiological methods, API 20E test-system (bioMerieux) according to the manufacturer’s instructions. Re- sults. The identifi cation results for Erwinia amylovora, Pectobacterium carotovorum and Pantoea agglome- rans isolates were derived from the conventional and API 20E test systems, which, were in line with the literature data for these species. The API 20E test-system showed high suitability for P. agglomerans isolates identifi cation. Although not all the species of facultatively anaerobic phytopathogenic bacteria may be identi- fi ed using API 20E test-system, its application will surely allow obtaining reliable data about their physiologi- cal and biochemical properties, valuable for identifi cation of bacteria, in the course of 24 h. Conclusions. The results of tests, obtained for investigated species while using API 20E test-system, and those of conventional microbiological methods coincided. The application of API 20E test-system (bioMerieux) ensures fast obtain- ing of important data, which may be used to identify phytopathogenic bacteria of Erwinia, Pectobacterium, Pantoea genera.

Electrophysiological Characterization of Transport Across Outer Membrane Channels from Gram-Negative Bacteria in Their Native Environment

2019 ◽  
Author(s):  
Jiajun Wang ◽  
Rémi Terrasse ◽  
Jayesh Arun Bafna ◽  
Lorraine Benier ◽  
Mathias Winterhalter
Keyword(s):  
Outer Membrane ◽  
Lipid Membrane ◽  
Membrane Vesicles ◽  
Outer Membrane Vesicles ◽  
Multi Drug Resistance ◽  
Gram Negative Bacteria ◽  
Membrane Channels ◽  
Gram Negative ◽  
Electrophysiological Characterization

Multi-drug resistance in Gram-negative bacteria is often associated with low permeability of the outer membrane. To investigate the role of membrane channels in the uptake of antibiotics, we extract, purify and reconstitute them into artificial planar membranes. To avoid this time-consuming procedure, here we show a robust approach using fusion of native outer membrane vesicles (OMV) into planar lipid bilayer which moreover allows also to some extend the characterization of membrane protein channels in their native environment. Two major membrane channels from <i>Escherichia coli</i>, OmpF and OmpC, were overexpressed from the host and the corresponding OMVs were collected. Each OMV fusion revealed surprisingly single or only few channel activities. The asymmetry of the OMV´s translates after fusion into the lipid membrane with the LPS dominantly present at the side of OMV addition. Compared to conventional reconstitution methods, the channels fused from OMVs containing LPS have similar conductance but a much broader distribution. The addition of Enrofloxacin on the LPS side yields somewhat higher association (<i>k<sub>on</sub></i>) and lower dissociation (<i>k<sub>off</sub></i>) rates compared to LPS-free reconstitution. We conclude that using outer membrane vesicles is a fast and easy approach for functional and structural studies of membrane channels in the native membrane.

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