The Use of Oxalate to Produce Free-living Cells from Carrot Tissue Cultures

Science ◽  
1951 ◽  
Vol 113 (2937) ◽  
pp. 407-408 ◽  
Author(s):  
R. D. Northcraft
Keyword(s):  
Living Cells ◽  
Tissue Cultures ◽  
Free Living

scholarly journals Engineered ACC deaminase-expressing free-living cells of Mesorhizobium loti show increased nodulation efficiency and competitiveness on Lotus spp.

2010 ◽  
Vol 56 (4) ◽  
pp. 331-338 ◽  
Author(s):  
Valeria P. Conforte ◽  
Mariela Echeverria ◽  
Cintia Sánchez ◽  
Rodolfo A. Ugalde ◽  
Ana B. Menéndez ◽  
...  
Keyword(s):  
Acc Deaminase ◽  
Living Cells ◽  
Free Living ◽  
Mesorhizobium Loti

scholarly journals Acetoacetyl Coenzyme A Reductase and Polyhydroxybutyrate Synthesis in Rhizobium(Cicer) sp. Strain CC 1192

1998 ◽  
Vol 64 (8) ◽  
pp. 2859-2863 ◽  
Author(s):  
Shahid N. Chohan ◽  
Les Copeland
Keyword(s):  
Coenzyme A ◽  
Citrate Synthase ◽  
Living Cells ◽  
High Ratio ◽  
Free Living ◽  
Insoluble Material ◽  
Living State ◽  
Biochemical Level ◽  
Coa Reductase ◽  
Acetoacetyl Coa Reductase

ABSTRACT Biochemical controls that regulate the biosynthesis of poly-3-hydroxybutyrate (PHB) were investigated in Rhizobium(Cicer) sp. strain CC 1192. This species is of interest for studying PHB synthesis because the polymer accumulates to a large extent in free-living cells but not in bacteroids during nitrogen-fixing symbiosis with chickpea (Cicer arietinumL.) plants. Evidence is presented that indicates that CC 1192 cells retain the enzymic capacity to synthesize PHB when they differentiate from the free-living state to the bacteroid state. This evidence includes the incorporation by CC 1192 bacteroids of radiolabel from [14C]malate into 3-hydroxybutyrate which was derived by chemically degrading insoluble material from bacteroid pellets. Furthermore, the presence of an NADPH-dependent acetoacetyl coenzyme A (CoA) reductase, which was specific forR-(−)-3-hydroxybutyryl-CoA and NADP+ in the oxidative direction, was demonstrated in extracts from free-living and bacteroid cells of CC 1192. Activity of this enzyme in the reductive direction appeared to be regulated at the biochemical level mainly by the availability of substrates. The CC 1192 cells also contained an NADH-specific acetoacetyl-CoA reductase which oxidizedS-(+)-3-hydroxybutyryl-CoA. A membrane preparation from CC 1192 bacteroids readily oxidized NADH but not NADPH, which is suggested to be a major source of reductant for nitrogenase. Thus, a high ratio of NADPH to NADP+, which could enhance delivery of reductant to nitrogenase, could also favor the reduction of acetoacetyl-CoA for PHB synthesis. This would mean that fine controls that regulate the partitioning of acetyl-CoA between citrate synthase and 3-ketothiolase are important in determining whether PHB accumulates.

scholarly journals STUDIES ON AN UNCOMPLICATED CORYZA OF THE DOMESTIC FOWL

1936 ◽  
Vol 64 (5) ◽  
pp. 749-758 ◽  
Author(s):  
John B. Nelson
Keyword(s):  
Microscopic Examination ◽  
Domestic Fowl ◽  
Living Cells ◽  
Fetal Membranes ◽  
Tissue Cultures ◽  
Morphological Identity

The coccobacilliform bodies of fowl coryza were successfully cultivated in the fetal membranes of fertile eggs. Microscopic examination indicated growth in approximately 50 per cent of 94 eggs inoculated on the 3rd to 4th day of incubation. Growth was generally inhibited, however, in eggs inoculated on the 10th day. One strain of the specific bodies was maintained through 11 successive passages in 4 day eggs. A more consistent growth of the coccobacilliform bodies was obtained in tissue cultures. One strain, originally isolated in November, 1935, has been carried through 100 successive subcultures at intervals of 1–3 days. The specific bodies fail to maintain their morphological identity for any length of time in this medium. It is noted that growth of the coccobacilliform bodies in fertile eggs and in tissue cultures is not dependent on the presence of living cells.

Ability of free-living cells ofBradyrhizobium japonicum to denitrify in soils

1989 ◽  
Vol 7 (3) ◽  
pp. 219-224 ◽  
Author(s):  
G. A. Breitenbeck ◽  
J. M. Bremner
Keyword(s):  
Living Cells ◽  
Free Living

scholarly journals Note on the surface electric charges of living cells

1911 ◽  
Vol 84 (571) ◽  
pp. 217-226 ◽  
Keyword(s):  
Thin Films ◽  
Electric Current ◽  
Living Cells ◽  
Yeast Cells ◽  
Microscopical Examination ◽  
Animal Cells ◽  
Cover Glass ◽  
Free Living ◽  
The Way

The movement of free living cells suspended in a fluid through which an electric current is passing towards one or other of the poles has been described by many observes. In almost every case the movement has been observed in thin films of fluid under a cover-glass mounted in the way usual for microscopical examination. The cells do not always all move in the same direction; some migrate towards the anode, others to the cathode, and Thornton found that in mixed suspensions of diatoms and amœbæ, or yeast cells and red blood corpuscles, the animal cells migrated to the anode, the vegetable cells to the cathode. He infers from this that animal and vegetable cells are oppositely electrified, the former being negative, the latter positive, to the fluid. It is obvious at the outset that there are exceptions to this generalisation, for Becholt describes a movement of bacteria towards the anode, the direction being reserved after agglutination. Dale and Lillie also have described movements of animal cells to the cathode, but Thornton points out with some justice that in these cases the cells were not in their normal habitat.

scholarly journals Vibriophages Differentially Influence Biofilm Formation by Vibrio anguillarum Strains

2015 ◽  
Vol 81 (13) ◽  
pp. 4489-4497 ◽  
Author(s):  
Demeng Tan ◽  
Amalie Dahl ◽  
Mathias Middelboe
Keyword(s):  
Biofilm Formation ◽  
Vibrio Anguillarum ◽  
Living Cells ◽  
Phage Infection ◽  
Host Cells ◽  
Free Living ◽  
Marine Aquaculture ◽  
Content Type ◽  
Host Interactions ◽  
Biofilm Development

ABSTRACTVibrio anguillarumis an important pathogen in marine aquaculture, responsible for vibriosis. Bacteriophages can potentially be used to control bacterial pathogens; however, successful application of phages requires a detailed understanding of phage-host interactions under both free-living and surface-associated growth conditions. In this study, we exploredin vitrophage-host interactions in two different strains ofV. anguillarum(BA35 and PF430-3) during growth in microcolonies, biofilms, and free-living cells. Two vibriophages, ΦH20 (Siphoviridae) and KVP40 (Myoviridae), had completely different effects on the biofilm development. Addition of phage ΦH20 to strain BA35 showed efficient control of biofilm formation and density of free-living cells. The interactions between BA35 and ΦH20 were thus characterized by a strong phage control of the phage-sensitive population and subsequent selection for phage-resistant mutants. Addition of phage KVP40 to strain PF430-3 resulted in increased biofilm development, especially during the early stage. Subsequent experiments in liquid cultures showed that addition of phage KVP40 stimulated the aggregation of host cells, which protected the cells against phage infection. By the formation of biofilms, strain PF430-3 created spatial refuges that protected the host from phage infection and allowed coexistence between phage-sensitive cells and lytic phage KVP40. Together, the results demonstrate highly variable phage protection mechanisms in two closely relatedV. anguillarumstrains, thus emphasizing the challenges of using phages to control vibriosis in aquaculture and adding to the complex roles of phages as drivers of prokaryotic diversity and population dynamics.

scholarly journals Selected Antimicrobial Essential Oils Eradicate Pseudomonas spp. and Staphylococcus aureus Biofilms

2012 ◽  
Vol 78 (11) ◽  
pp. 4057-4061 ◽  
Author(s):  
Nicole L. Kavanaugh ◽  
Katharina Ribbeck
Keyword(s):  
Staphylococcus Aureus ◽  
Antibiotic Resistance ◽  
Essential Oils ◽  
Living Cells ◽  
Free Living ◽  
Pseudomonas Spp ◽  
Antimicrobial Treatments ◽  
And Staphylococcus Aureus

ABSTRACTBiofilms are difficult to eliminate with standard antimicrobial treatments due to their high antibiotic resistance relative to free-living cells. Here, we show that selected antimicrobial essential oils can eradicate bacteria within biofilms with higher efficiency than certain important antibiotics, making them interesting candidates for the treatment of biofilms.

scholarly journals Symbiotic Bradyrhizobium japonicum Reduces N2O Surrounding the Soybean Root System via Nitrous Oxide Reductase

2006 ◽  
Vol 72 (4) ◽  
pp. 2526-2532 ◽  
Author(s):  
Reiko Sameshima-Saito ◽  
Kaori Chiba ◽  
Junta Hirayama ◽  
Manabu Itakura ◽  
Hisayuki Mitsui ◽  
...  
Keyword(s):  
Nitrous Oxide ◽  
Root System ◽  
Bradyrhizobium Japonicum ◽  
Reductase Activity ◽  
Ambient Air ◽  
Living Cells ◽  
Nitrous Oxide Reductase ◽  
Free Living ◽  
Low Concentrations ◽  
Soybean Roots

ABSTRACT N2O reductase activity in soybean nodules formed with Bradyrhizobium japonicum was evaluated from N2O uptake and conversion of 15N-N2O into 15N-N2. Free-living cells of USDA110 showed N2O reductase activity, whereas a nosZ mutant did not. Complementation of the nosZ mutant with two cosmids containing the nosRZDFYLX genes of B. japonicum USDA110 restored the N2O reductase activity. When detached soybean nodules formed with USDA110 were fed with 15N-N2O, they rapidly emitted 15N-N2 outside the nodules at a ratio of 98.5% of 15N-N2O uptake, but nodules inoculated with the nosZ mutant did not. Surprisingly, N2O uptake by soybean roots nodulated with USDA110 was observed even in ambient air containing a low concentration of N2O (0.34 ppm). These results indicate that the conversion of N2O to N2 depends exclusively on the respiratory N2O reductase and that soybean roots nodulated with B. japonicum carrying the nos genes are able to remove very low concentrations of N2O.

Sign in / Sign up

Export Citation Format

Share Document