The calculated nitrogen requirements of a single cell of Escherichia coli

1968 ◽  
Vol 14 (4) ◽  
pp. 480-481
Author(s):  
D. E. Hunt ◽  
R. F. Pittillo
Keyword(s):  
Escherichia Coli ◽  
Single Cell ◽  
Nitrogen Source ◽  
Ammonium Chloride ◽  
Relative Number ◽  
Series Of Experiments

A chemically defined broth medium, deficient in a growth-limiting nitrogen source, was used in a series of experiments which alllowed the calculation of the relative number of ammonium chloride molecules (approximately 1.0 × 109) required for one division cycle of a single cell of Escherichia coli.

scholarly journals AES and ToF-SIMS combination for single cell chemical imaging of gold nanoparticle-labeled Escherichia coli

2021 ◽  
Author(s):  
Cecile COURREGES ◽  
Mélanie Bonnecaze ◽  
Delphine Flahaut ◽  
Sophie Nolivos ◽  
Regis Grimaud ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Gold Nanoparticles ◽  
Single Cell ◽  
Electron Spectroscopy ◽  
Auger Electron ◽  
Chemical Imaging ◽  
Single Cell Level ◽  
Cell Level ◽  
Tof Sims ◽  
Escherichia Coli Cells

A chemical fingerprint of Escherichia coli cells surface labeled by gelatin coated gold nanoparticles was obtained by combining Auger Electron Spectroscopy (AES) for single cell level chemical images, and Time-of-Flight...

Anatomical distribution of brainstem sites where PGE1 induces hyperthermia in macaque species

1993 ◽  
Vol 71 (5-6) ◽  
pp. 414-424 ◽  
Author(s):  
C.W. Simpson ◽  
W. D. Ruwe ◽  
R. D. Myers
Keyword(s):  
Escherichia Coli ◽  
Macaca Mulatta ◽  
Preoptic Area ◽  
Macaca Nemestrina ◽  
Prostaglandin E ◽  
Bacterial Pyrogen ◽  
Hyperthermic Response ◽  
Series Of Experiments ◽  
Endogenous Activity ◽  
Hypothalamic Preoptic Area

The neuroanatomical distribution of sites in the diencephalon and mesencephalon within which a prostaglandin (PG) of the E series elicits hyperthermia was characterized in Macaca mulatta and Macaca nemestrina. In 420 experiments undertaken in 13 animals, 225 loci were examined for their reactivity to PGE1 microinjected in a dose of 30 or 100 ng given in a volume of 1.0–1.5 μL. The regions of the brainstem for injection extended rostrally from the thermosensitive cells of the anterior hypothalamic, preoptic area (AH/POA) to the caudal border of the mesencephalon. Colonic and skin temperatures of the monkeys were measured continuously by thermistor probes. A hyperthermic response of ≥0.5 °C and a latency of ≤45 min was evoked by PGE1 within sites located primarily in the AH/POA. When PGE1 was microinjected at loci located caudal to the AH/POA, the elevation in body temperature (Tb) not only was less intense but rose at a slower rate. A higher concentration of PGE1 in these caudal regions was required to induce hyperthermia comparable with that elicited at loci within the AH/POA. In a second series of experiments either 1.0–5.0 μg 5-hydroxytryptamine (serotonin) or a concentration of 108 organisms/mL of Escherichia coli was microinjected at PGE1-reactive sites. A close anatomical concordance within the AH/POA of the animal was found in terms of the temporal characteristics and magnitude of the hyperthermia evoked by the indoleamine or lipopolysaccharide. The present results coincide with the reported neuroanatomical distribution of sites in the diencephalon and mesencephalon of other species in which PGE1 causes hyperthermia. Furthermore, these findings support the concept that the local neuronal mechanism of action of a pyrogen in the brainstem of the primate may involve phasic changes in the endogenous activity of both the serotonergic pathway and cyclo-oxygenase system in the AH/POA. In turn, their commonality of action suggests a functional similarity in their effect of shifting the set point for Tb.Key words: prostaglandin E1, hyperthermia, serotonin, Escherichia coli, anterior hypothalamus, thermoregulation, bacterial pyrogen, preoptic area, neuroanatomical localization, Macaca nemestrina, Macaca mulatta.

Ammoximation of cyclohexanone to cyclohexanone oxime using ammonium chloride as nitrogen source

2016 ◽  
Vol 152 ◽  
pp. 717-723 ◽  
Author(s):  
Yuanyuan Xu ◽  
Qiusheng Yang ◽  
Zhihui Li ◽  
Liya Gao ◽  
Dongsheng Zhang ◽  
...  
Keyword(s):  
Nitrogen Source ◽  
Ammonium Chloride ◽  
Cyclohexanone Oxime

scholarly journals Cell-to-cell heterogeneity in Escherichia coli stress response originates from pulsatile expression and growth

2020 ◽  
Author(s):  
Nadia M. V. Sampaio ◽  
Caroline M. Blassick ◽  
Jean-Baptiste Lugagne ◽  
Mary J. Dunlop
Keyword(s):  
Gene Expression ◽  
Escherichia Coli ◽  
Stress Response ◽  
Single Cell ◽  
Phenotypic Variability ◽  
Growth Dynamics ◽  
Time Lapse ◽  
Cell Heterogeneity ◽  
Temporal Expression ◽  
Functional Consequences

AbstractCell-to-cell heterogeneity in gene expression and growth can have critical functional consequences, such as determining whether individual bacteria survive or die following stress. Although phenotypic variability is well documented, the dynamics that underlie it are often unknown. This information is critical because dramatically different outcomes can arise from gradual versus rapid changes in expression and growth. Using single-cell time-lapse microscopy, we measured the temporal expression of a suite of stress response reporters in Escherichia coli, while simultaneously monitoring growth rate. In conditions without stress, we found widespread examples of pulsatile expression. Single-cell growth rates were often anti-correlated with gene expression, with changes in growth preceding changes in expression. These pulsatile dynamics have functional consequences, which we demonstrate by measuring survival after challenging cells with the antibiotic ciprofloxacin. Our results suggest that pulsatile expression and growth dynamics are common in stress response networks and can have direct consequences for survival.

scholarly journals The combination of Elephantopus scaber and Sauropus androgynus promotes erythroid lineages and modulates follicle-stimulating hormone and luteinizing hormone levels in pregnant mice infected with Escherichia coli

2021 ◽  
pp. 1398-1404
Author(s):  
Muhammad Sasmito Djati ◽  
Yuyun Ika Christina ◽  
Muhaimin Rifa'i
Keyword(s):  
Escherichia Coli ◽  
Luteinizing Hormone ◽  
Follicle Stimulating Hormone ◽  
Relative Number ◽  
Enzyme Linked Immunosorbent Assay ◽  
Hormone Levels ◽  
E Coli ◽  
Pregnant Mice ◽  
Elephantopus Scaber ◽  
Stimulating Hormone

Background and Aim: Escherichia coli infection produces an adverse effect on the erythrocyte lineage and hormone levels during pregnancy. This study aimed to evaluate the effects of Elephantopus scaber (ES) and Sauropus androgynus (SA) in combination on circulating follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels and erythropoiesis changes in E. coli-infected pregnant mice. Materials and Methods: Female Balb/c mice were mated with normal male mice and pregnancies were identified by the formation of vaginal plugs. Twenty-eight pregnant mice were divided randomly into seven groups: A control group (N), E. coli-infected pregnant mice (K+), and infected pregnant mice received the following five treatments: (1) Only ES; (2) ESSA1 (75:25); (3) ESSA2 (50:50); (4) ESSA3 (25:75); and (5) only SA, beginning from the 1st to the 16th day of pregnancy. Pregnant mice were infected with 107 CFU/mL of E. coli on day 4. Blood serum was collected on days 8, 12, and 16 of pregnancy and LH and FSH levels were measured by enzyme-linked immunosorbent assay. Bone marrow was isolated to determine the relative number of TER-119+VLA4+ and TER-119+CD34+ using flow cytometry. Results: The ESSA1 and SA groups exhibited a marked increase in LH levels. The combination of ES and SA administered at a 25:75 ratio (ESSA3) altered FSH levels and the relative number of TER-119+VLA4+ in infected pregnant mice. Combined with SA at an equal ratio (50:50), ESSA2 group exhibited a significant increase in the expression of TER119+CD34+ compared with the other treatment groups. Conclusion: ES and SA combined at a ratio of 25:75 exhibited optimal results in altering hormonal and erythropoiesis in infected pregnant mice.

scholarly journals Influence of Type I Fimbriae and Fluid Shear Stress on Bacterial Behavior and Multicellular Architecture of Early Escherichia coli Biofilms at Single-Cell Resolution

2018 ◽  
Vol 84 (6) ◽  
Author(s):  
Liyun Wang ◽  
Robert Keatch ◽  
Qi Zhao ◽  
John A. Wright ◽  
Clare E. Bryant ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Shear Stress ◽  
Single Cell ◽  
Biofilm Formation ◽  
Fluid Shear Stress ◽  
Cell Membrane Permeability ◽  
Type I ◽  
Fluid Shear ◽  
Content Type ◽  
Type I Fimbriae

ABSTRACT Biofilm formation on abiotic surfaces in the food and medical industry can cause severe contamination and infection, yet how biological and physical factors determine the cellular architecture of early biofilms and the bacterial behavior of the constituent cells remains largely unknown. In this study, we examined the specific role of type I fimbriae in nascent stages of biofilm formation and the response of microcolonies to environmental flow shear at the single-cell resolution. The results show that type I fimbriae are not required for reversible adhesion from plankton, but they are critical for the irreversible adhesion of Escherichia coli strain MG1655 cells that form biofilms on polyethylene terephthalate (PET) surfaces. Besides establishing firm cell surface contact, the irreversible adhesion seems necessary to initiate the proliferation of E. coli on the surface. After the application of shear stress, bacterial retention is dominated by the three-dimensional architecture of colonies, independent of the population size, and the multilayered structure could protect the embedded cells from being insulted by fluid shear, while the cell membrane permeability mainly depends on the biofilm population size and the duration of the shear stress. IMPORTANCE Bacterial biofilms could lead to severe contamination problems in medical devices and food processing equipment. However, biofilms are usually studied at a rough macroscopic level; thus, little is known about how individual bacterium behavior within biofilms and the multicellular architecture are influenced by bacterial appendages (e.g., pili/fimbriae) and environmental factors during early biofilm formation. We applied confocal laser scanning microscopy (CLSM) to visualize Escherichia coli microcolonies at a single-cell resolution. Our findings suggest that type I fimbriae are vital to the initiation of bacterial proliferation on surfaces. We also found that the fluid shear stress affects the biofilm architecture and cell membrane permeability of the constituent bacteria in a different way: the onset of the biofilm is linked with the three-dimensional morphology, while membranes are regulated by the overall population of microcolonies.

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