Viability and Adaptability of E. coli. and Enterococcus Group to Salt Water with High Concentration of Sodium Chloride

1982 ◽  
Vol 14 (4-5) ◽  
pp. 115-126 ◽  
Author(s):  
T Omura ◽  
M Onuma ◽  
Y Hashimoto
Keyword(s):  
Sodium Chloride ◽  
Salt Water ◽  
The Other ◽  
Type I ◽  
Citrobacter Freundii ◽  
Type Ii ◽  
High Concentration ◽  
E Coli ◽  
Rapid Extinction ◽  
Other Hand

Some experiments were carried out to examine the adaptability of E. coli. and enterococcus group to salt water with high concentration of sodium chloride after the experiments on viability in this salt water. Unlike E. coli. type I, when E.coli. type II was repeatedly exposed to salt water, the survival of E.coli. type II was changed from rapid extinction to multiplication as the experiments went on. At the same time, it was also made clear by means of the IMViC test that E.coli. type II was replaced by Citrobacter freundii as E.coli. type II adapted itself to salt water. The enterococcus group was separated into four distinct types; S. faecalis, S. faecalis var. liquefaciens, S. faecium and S. durans. The results of the experiments on viability in salt water indicated that S. faecalis var. liquefaciens possessed the greatest viability, and S. faecium the weakest. From the results of the experiments on adaptability, it was found that each type of enterococcus group had a different adaptability to salt water. In spite of the weakest viability, S. faecium could adapt itself to salt water as well as S. faecalis and S. faecalis var. liquefaciens. On the other hand, S. durans could not adapt itself to salt water at all.

scholarly journals Effects of large-scale AGN feedback in local galaxies

2012 ◽  
Vol 8 (S292) ◽  
pp. 375-375
Author(s):  
Stanislav Shabala ◽  
Sugata Kaviraj ◽  
Joseph Silk
Keyword(s):  
Star Formation ◽  
Active Galactic Nucleus ◽  
Large Scale ◽  
The Other ◽  
Type I ◽  
Type Ii ◽  
Powerful Radio ◽  
Cluster Galaxies ◽  
Other Hand ◽  
Bow Shocks

AbstractThe effects of active galactic nucleus (AGN) feedback on group and cluster galaxies are investigated. We examine the colors of non-AGN hosts (i.e. satellite galaxies) by comparing galaxies overrun by radio AGN with similar galaxies located outside the radio AGN contours. We find that powerful Fanaroff-Riley type II (edge-brightened) radio AGN truncate star formation in the galaxies overrun by AGN-driven bow shocks. On the other hand, the ubiquitous Fanaroff-Riley type I (core-dominated) AGN do not affect neighboring galaxies. This result shows that, despite their rarity, feedback from powerful radio AGN is an important factor in the evolution of group/cluster galaxies.

scholarly journals Graded Rough Sets based on Neighborhood Operator Over two Different Universes and its Application

2021 ◽  
Author(s):  
Ahmed Mostafa Khalil
Keyword(s):  
Decision Making ◽  
Rough Set ◽  
Rough Sets ◽  
The Other ◽  
Type I ◽  
Type Ii ◽  
Type Iii ◽  
Other Hand ◽  
Decision Methods ◽  
Neighborhood Rough Sets

Abstract Abstract The major concern of this paper is to present the notion of rough set based on neighborhood operator on universe set, along with its properties, and examples. Then, we generalize several notions of covering rough sets to neighborhood rough sets with respect to the graded n. Further, we present some notions such as probabilistic neighborhood rough approximations of X, (Type-I / Type-II) probabilistic neighborhood rough approximations of X with error α and β, and (Type-I / Type-II) probabilistic neighborhood rough approximations of X with respect to N . The interesting properties of above notions are investigated in detail. On the other hand, we define the notion of rough set based on neighborhood operator over two different universes. Subsequently, we present some notions (Type-I / Type-II / Type-III) graded n-neighborhood rough sets and give a two approaches to decision-making problems based on the (Type-II / Type-III) grade n-neighborhood rough sets. Then, we construct the decision steps and give two algorithms of the decision methods. Also, we will give two illustrative examples to show the applicability of the rough set based on neighborhood operator over two different universes to solve the rough decision-making problems. Finally, we give a comparison between the Liu et al.’s approach and our approach.

scholarly journals Biochemical and structural characterization of the novel sialic acid-binding site of Escherichia coli heat-labile enterotoxin LT-IIb

2016 ◽  
Vol 473 (21) ◽  
pp. 3923-3936 ◽  
Author(s):  
Dani Zalem ◽  
João P. Ribeiro ◽  
Annabelle Varrot ◽  
Michael Lebens ◽  
Anne Imberty ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Binding Site ◽  
Cholera Toxin ◽  
Carbohydrate Binding ◽  
Type I ◽  
Type Ii ◽  
E Coli ◽  
B Subunit ◽  
Heat Labile ◽  
B Subunits

The structurally related AB5-type heat-labile enterotoxins of Escherichia coli and Vibrio cholerae are classified into two major types. The type I group includes cholera toxin (CT) and E. coli LT-I, whereas the type II subfamily comprises LT-IIa, LT-IIb and LT-IIc. The carbohydrate-binding specificities of LT-IIa, LT-IIb and LT-IIc are distinctive from those of cholera toxin and E. coli LT-I. Whereas CT and LT-I bind primarily to the GM1 ganglioside, LT-IIa binds to gangliosides GD1a, GD1b and GM1, LT-IIb binds to the GD1a and GT1b gangliosides, and LT-IIc binds to GM1, GM2, GM3 and GD1a. These previous studies of the binding properties of type II B-subunits have been focused on ganglio core chain gangliosides. To further define the carbohydrate binding specificity of LT-IIb B-subunits, we have investigated its binding to a collection of gangliosides and non-acid glycosphingolipids with different core chains. A high-affinity binding of LT-IIb B-subunits to gangliosides with a neolacto core chain, such as Neu5Gcα3- and Neu5Acα3-neolactohexaosylceramide, and Neu5Gcα3- and Neu5Acα3-neolactooctaosylceramide was detected. An LT-IIb-binding ganglioside was isolated from human small intestine and characterized as Neu5Acα3-neolactohexaosylceramide. The crystal structure of the B-subunit of LT-IIb with the pentasaccharide moiety of Neu5Acα3-neolactotetraosylceramide (Neu5Ac-nLT: Neu5Acα3Galβ4GlcNAcβ3Galβ4Glc) was determined providing the first information for a sialic-binding site in this subfamily, with clear differences from that of CT and LT-I.

Burn-in procedures for a generalized model

2001 ◽  
Vol 38 (02) ◽  
pp. 542-553 ◽  
Author(s):  
Ji Hwan Cha
Keyword(s):  
The Other ◽  
Replacement Policy ◽  
Type I ◽  
Type Ii ◽  
Failure Model ◽  
Minimal Repair ◽  
Optimal Replacement ◽  
Complete Repair ◽  
Optimal Replacement Policy ◽  
Type Of Failure

In this paper two burn-in procedures for a general failure model are considered. There are two types of failure in the general failure model. One is Type I failure (minor failure) which can be removed by a minimal repair or a complete repair and the other is Type II failure (catastrophic failure) which can be removed only by a complete repair. During a burn-in process, with burn-in Procedure I, the failed component is repaired completely regardless of the type of failure, whereas, with burn-in Procedure II, only minimal repair is done for the Type I failure and a complete repair is performed for the Type II failure. In field use, the component is replaced by a new burned-in component at the ‘field use age’ T or at the time of the first Type II failure, whichever occurs first. Under the model, the problems of determining optimal burn-in time and optimal replacement policy are considered. The two burn-in procedures are compared in cases when both the procedures are applicable.

scholarly journals Degradation of a Short-lived Glycoprotein from the Lumen of the Endoplasmic Reticulum: The Role of N-linked Glycans and the Unfolded Protein Response

1999 ◽  
Vol 10 (12) ◽  
pp. 4059-4073 ◽  
Author(s):  
Maddalena de Virgilio ◽  
Claudia Kitzmüller ◽  
Eva Schwaiger ◽  
Michael Klein ◽  
Gert Kreibich ◽  
...  
Keyword(s):  
Endoplasmic Reticulum ◽  
Unfolded Protein Response ◽  
The Other ◽  
Slow Phase ◽  
Type I ◽  
Unfolded Protein ◽  
Other Hand ◽  
The Unfolded Protein Response ◽  
Protein Response

We are studying endoplasmic reticulum–associated degradation (ERAD) with the use of a truncated variant of the type I ER transmembrane glycoprotein ribophorin I (RI). The mutant protein, RI332, containing only the N-terminal 332 amino acids of the luminal domain of RI, has been shown to interact with calnexin and to be a substrate for the ubiquitin-proteasome pathway. When RI332 was expressed in HeLa cells, it was degraded with biphasic kinetics; an initial, slow phase of ∼45 min was followed by a second phase of threefold accelerated degradation. On the other hand, the kinetics of degradation of a form of RI332 in which the single used N-glycosylation consensus site had been removed (RI332-Thr) was monophasic and rapid, implying a role of the N-linked glycan in the first proteolytic phase. RI332degradation was enhanced when the binding of glycoproteins to calnexin was prevented. Moreover, the truncated glycoprotein interacted with calnexin preferentially during the first proteolytic phase, which strongly suggests that binding of RI332 to the lectin-like protein may result in the slow, initial phase of degradation. Additionally, mannose trimming appears to be required for efficient proteolysis of RI332. After treatment of cells with the inhibitor of N-glycosylation, tunicamycin, destruction of the truncated RI variants was severely inhibited; likewise, in cells preincubated with the calcium ionophore A23187, both RI332 and RI332-Thr were stabilized, despite the presence or absence of the N-linked glycan. On the other hand, both drugs are known to trigger the unfolded protein response (UPR), resulting in the induction of BiP and other ER-resident proteins. Indeed, only in drug-treated cells could an interaction between BiP and RI332 and RI332-Thr be detected. Induction of BiP was also evident after overexpression of murine Ire1, an ER transmembrane kinase known to play a central role in the UPR pathway; at the same time, stabilization of RI332 was observed. Together, these results suggest that binding of the substrate proteins to UPR-induced chaperones affects their half lives.

Electrophysiological Characteristics of Classes of Neuron in the HVc of the Zebra Finch

1998 ◽  
Vol 80 (2) ◽  
pp. 914-923 ◽  
Author(s):  
Michinori Kubota ◽  
Ikuo Taniguchi
Keyword(s):  
Action Potential ◽  
Zebra Finch ◽  
Action Potential Duration ◽  
The Other ◽  
Time Dependent ◽  
Inward Rectification ◽  
Type I ◽  
Type Ii ◽  
Type Iii ◽  
Type Iv

Kubota, Michinori and Ikuo Taniguchi. Electrophysiological characteristics of classes of neuron in the HVc of the zebra finch. J. Neurophysiol. 80: 914–923, 1998. Whole cell recordings were made from zebra finch HVc neurons in slice preparations. Four distinct classes of neuron were found on the basis of their electrophysiological properties. The morphological characteristics of some of these neurons were also examined by intracellular injection of Lucifer yellow. Type I neurons (21 of 65 cells) had longer time-to-peak of an afterhyperpolarization following an action potential than the other classes. They exhibited both fast and time-dependent inward rectification and an initial high-frequency firing followed by a slower constant firing. Type I neurons had large somata and thick dendrites with many spines. The axons of some of the neurons in this class projected in the direction of area X of the parolfactory lobe. Type II neurons (30 of 65 cells) had a more negative resting membrane potential than the other classes. They exhibited fast inward rectification. Type II neurons could be divided into two subclasses by the absence (IIa; 22 cells) and the presence (IIb; 8 cells) of a low-threshold transient depolarization. Type IIa neurons had relatively small somata and thin, spiny dendrites. The axons of some of the neurons in this class projected in the direction of the robust nucleus of the archistriatum (RA). Type IIb neurons had relatively large somata and thick dendrites with many spines. Type III neurons (6 of 65 cells) had a shorter action-potential duration than the other classes. They exhibited prominent time-dependent inward rectification and a regular tonic firing with little or no accommodation. Type III neurons had beaded, aspiny dendrites. Type IV neurons (8 of 65 cells) had a longer action-potential duration, a much larger input resistance, and longer membrane time constant than the other classes. Type IV neurons had small somata and thin, short, sparsely spiny dendrites. The axons of some of the neurons in this class projected in the direction of the RA. These classes of neuron may play distinct roles in song production and representation in the HVc.

Aldosterone binding sites along nephron of Xenopus and rabbit

1989 ◽  
Vol 257 (1) ◽  
pp. R87-R95 ◽  
Author(s):  
A. Gnionsahe ◽  
M. Claire ◽  
N. Koechlin ◽  
J. P. Bonvalet ◽  
N. Farman
Keyword(s):  
Binding Sites ◽  
Direct Evidence ◽  
Distal Tubule ◽  
Distal Segment ◽  
The Other ◽  
Type I ◽  
Thick Ascending Limb ◽  
Type Ii ◽  
Straight Segment ◽  
Dry Film

Distal segment of several amphibians exhibits aldosterone-modulated ion transport properties. On the other hand, A6 cells, derived from Xenopus laevis (XL) kidney, are aldosterone sensitive. We examined the distribution of aldosterone binding sites in isolated tubules of XL compared with rabbit. After incubation with 2 nM [3H]aldosterone, microdissected tubular segments from proximal (PT), distal straight segment (DST), and flask cell collecting (CT) tubules from XL and from rabbit cortical thick ascending limb (CTAL), connecting (CNT), and collecting (CCD) tubules were processed for dry film autoradiography. In XL, specific nuclear labeling of type I (mineralocorticoid) sites was restricted to DST. Labeling of type II (glucocorticoid) sites was present all along the tubule. No specific cytoplasmic labeling was observed, except for type II sites in PT. In the rabbit, aldosterone binds to both type I and type II sites in the three tubular segments studied. In these segments, the binding was about fourfold higher than in DST of XL. These results bring direct evidence in designating the distal tubule of amphibians as a target epithelium for aldosterone. In addition, they suggest that A6 cell line may derive from DST of the Xenopus nephron.

scholarly journals Toxin–Antitoxin Systems in Bacillus subtilis

Toxins ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 262 ◽  
Author(s):  
Sabine Brantl ◽  
Peter Müller
Keyword(s):  
Bacillus Subtilis ◽  
Physiological Role ◽  
Present Knowledge ◽  
The Other ◽  
Type I ◽  
Type Ii ◽  
Free Living ◽  
Bacterial Chromosomes ◽  
Maintenance Systems ◽  
Living Bacteria

Toxin–antitoxin (TA) systems were originally discovered as plasmid maintenance systems in a multitude of free-living bacteria, but were afterwards found to also be widespread in bacterial chromosomes. TA loci comprise two genes, one coding for a stable toxin whose overexpression kills the cell or causes growth stasis, and the other coding for an unstable antitoxin that counteracts toxin action. Of the currently known six types of TA systems, in Bacillus subtilis, so far only type I and type II TA systems were found, all encoded on the chromosome. Here, we review our present knowledge of these systems, the mechanisms of antitoxin and toxin action, and the regulation of their expression, and we discuss their evolution and possible physiological role.

scholarly journals Rate constants rather than biochemical mechanism determine behaviour of genetic clocks

2008 ◽  
Vol 5 (suppl_1) ◽  
Author(s):  
Emery Conrad ◽  
Avraham E Mayo ◽  
Alexander J Ninfa ◽  
Daniel B Forger
Keyword(s):  
Transcription Regulation ◽  
Negative Feedback ◽  
Rate Constants ◽  
The Other ◽  
Type I ◽  
Type Ii ◽  
Biochemical Mechanism ◽  
Wide Range ◽  
Negative Feedbacks ◽  
Positive And Negative Feedbacks

Many biological systems contain both positive and negative feedbacks. These are often classified as resonators or integrators. Resonators respond preferentially to oscillating signals of a particular frequency. Integrators, on the other hand, accumulate a response to signals. Computational neuroscientists often refer to neurons showing integrator properties as type I neurons and those showing resonator properties as type II neurons. Guantes & Poyatos have shown that type I or type II behaviour can be seen in genetic clocks. They argue that when negative feedback occurs through transcription regulation and post-translationally, genetic clocks act as integrators and resonators, respectively. Here we show that either behaviour can be seen with either design and in a wide range of genetic clocks. This highlights the importance of parameters rather than biochemical mechanism in determining the system behaviour.

Pyrophosphates of Tetravalent Elements and a Mössbauer Study of SnP2O7

1975 ◽  
Vol 53 (1) ◽  
pp. 79-91 ◽  
Author(s):  
Chung-Hsi Huang ◽  
Osvald Knop ◽  
David A. Othen ◽  
Frank W. D. Woodhams ◽  
R. Allan Howie
Keyword(s):  
Chemical Shift ◽  
Electric Field ◽  
Electric Field Gradient ◽  
The Other ◽  
Type I ◽  
Type Ii ◽  
Transition Elements ◽  
Mössbauer Study ◽  
X Ray ◽  
Ionic Compounds

Cubic M4+P2O7 pyrophosphates of Ti, Zr, Hf, Sn, and Pb have been examined by X-ray powder diffractometry and by infrared, Raman, and Mössbauer 119Sn spectroscopy. The tin compound appeared to be of Chaunac's type I (with P2O7 groups oriented at random) and could be converted to type II (with ordered P2O7 groups) by heating to high temperatures. All the other preparations were of Chaunac's type II. Evidence from lattice parameters and intensity features of the Raman spectra suggests that the cubic MP2O7 pyrophosphates fall in two groups, one containing the compounds of the typical elements (Ge, Sn, Pb) and the other, the compounds of the transition elements. No support has been found for the view that the P—O—P groupings of the pyrophosphate anion in these compounds are linear. The 119Sn chemical shift in SnP2O7 is only slightly less negative than the shift in CuSnF6.4H2O, which makes SnP2O7 one of the most ionic compounds of tetravalent tin known. The observed quadrupole splitting in the Mössbauer spectrum of SnP2O7 arises largely from the contribution of the valence term to the electric field gradient at the Sn atom.

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