[5] In Vitro assay for reiterative transcription during transcriptional initiation by Escherichia coli RNA polymerase

1996 ◽  
pp. 71-85 ◽  
Author(s):  
Fengxia Qi ◽  
Chongguang Liu ◽  
Lucie S. Heath ◽  
Charles L. Turnbough
Keyword(s):  
Escherichia Coli ◽  
Rna Polymerase ◽  
In Vitro Assay ◽  
Transcriptional Initiation ◽  
Vitro Assay ◽  
Reiterative Transcription

scholarly journals Purification of the RelB and RelE Proteins ofEscherichia coli: RelE Binds to RelB and to Ribosomes

2001 ◽  
Vol 183 (8) ◽  
pp. 2700-2703 ◽  
Author(s):  
Cheryl Galvani ◽  
Jefferson Terry ◽  
Edward E. Ishiguro
Keyword(s):  
Escherichia Coli ◽  
Direct Interaction ◽  
Binding Activity ◽  
In Vitro Assay ◽  
Ofescherichia Coli ◽  
Yeast Two Hybrid ◽  
Vitro Assay ◽  
Ribosome Binding ◽  
Two Hybrid

ABSTRACT The direct interaction of the Escherichia colicytotoxin RelE with its specific antidote, RelB, was demonstrated in two ways: (i) copurification of the two proteins and (ii) a positive yeast two-hybrid assay involving the relB andrelE genes. In addition, the purified RelE protein exhibited ribosome-binding activity in an in vitro assay, supporting previous observations suggesting that it is an inhibitor of translation.

scholarly journals In vitro assay for phagocytic activity by canine neutrophils for Escherichia coli

2018 ◽  
Vol 65 (1) ◽  
pp. 1
Author(s):  
A. P. Liyanage ◽  
M. R. C. K. Mallawa ◽  
I. D. Silva
Keyword(s):  
Escherichia Coli ◽  
Phagocytic Activity ◽  
In Vitro Assay ◽  
Vitro Assay

Vesicular Lipid Nanoparticles (Liposomes) for the Treatment of Medical Device Infections

2011 ◽  
Vol 1316 ◽  
Author(s):  
Erik Taylor ◽  
Anubhav Kaviratna ◽  
Rinti Banerjee ◽  
Thomas J. Webster
Keyword(s):  
Escherichia Coli ◽  
Biofilm Formation ◽  
Lipid Nanoparticles ◽  
In Vitro Assay ◽  
Silver Sulfadiazine ◽  
Human Pathogens ◽  
Vitro Assay ◽  
First Time ◽  
Better Than

AbstractLiposomes (a phospholipid bi-layer which can be formulated to contain drugs or other reagents) composed of endogenous phospholipid dipalmitoylphosphatidylcholine (DPPC) in combination with dioleoylphosphatidylethanolamine (DOPE), lauric acid, and silver sulfadiazine were made into vesicular nanoparticles in this study using an optimized extrusion technique. Liposomes were then tested for antibacterial activity against a range of bacteria species including Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, and Bacillus subtilis (all are relevant human pathogens known to infect implants) and were also challenged to prevent the growth of adherent biofilms (a robust slimy extracellular matrix) through an in vitro assay relevant to device related infections. It was found that all liposomes reduced bacterial growth, and, most importantly, liposomes containing DPPC and DOPE reduced biofilm formation better than the commercially available antibiotic silver sulfadiazine. These results indicated for the first time that such liposomes might be a better approach to prevent device related infections.

An In Vitro Assay To Evaluate Competitive Exclusion Products for Poultry

2002 ◽  
Vol 65 (5) ◽  
pp. 746-751 ◽  
Author(s):  
R. DOUG WAGNER ◽  
MICHAEL HOLLAND ◽  
CARL E. CERNIGLIA
Keyword(s):  
Escherichia Coli ◽  
Cell Lines ◽  
Competitive Exclusion ◽  
In Vitro Assay ◽  
Vitro Assay ◽  
In Vivo Testing ◽  
Commercial Poultry ◽  
Bacterial Mixtures

An in vitro assay was developed to measure the ability of competitive exclusion (CE) bacteria to protect Caco-2 and CRL-2117 epithelial cells from invasion by Salmonella Typhimurium. The proposed assay is needed to expedite the development of defined-flora CE products. The average significantly protective concentration of the commercial poultry-specific CE product Preempt was 4.05 log CFU/6.41 log human Caco-2 cells and 3.71 log CFU/6.89 log CFU chicken CRL-2117 cells. Enterococcus faecalis isolated from Preempt protected CRL-2117 cells, Escherichia coli isolates protected Caco-2 cells, Lactococcus lactis and Bacteroides distasonis isolates protected both cell lines, and three species of Lactobacillus isolates failed to protect either cell line. A defined mixture of 29 strains of bacteria similar to the constituents of Preempt protected both cell lines from Salmonella invasion at a concentration of 7.83 log CFU. The constituents of the defined CE culture were separated into mixtures of obligate (8.42 log CFU) and facultative (8.49 log CFU) anaerobes, which both protected the cell lines, suggesting that both types of bacteria were equally protective. Although not a substitute for in vivo testing, the in vitro CE assay is a rapid technique for the evaluation of bacterial mixtures for potential CE products.

scholarly journals Soluble GPI8 restores glycosylphosphatidylinositol anchoring in a trypanosome cell-free system depleted of lumenal endoplasmic reticulum proteins

2000 ◽  
Vol 351 (3) ◽  
pp. 717-722 ◽  
Author(s):  
Deepak K. SHARMA ◽  
James D. HILLEY ◽  
James D. BANGS ◽  
Graham H. COOMBS ◽  
Jeremy C. MOTTRAM ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Endoplasmic Reticulum ◽  
Active Component ◽  
In Vitro Assay ◽  
Leishmania Mexicana ◽  
Size Fractionation ◽  
Vitro Assay ◽  
Free System ◽  
High Ph

We previously established an in vitro assay for glycosylphosphatidylinositol (GPI) anchoring of proteins using trypanosome membranes. We now show that GPI anchoring is lost when the membranes are washed at high pH and restored to physiological pH prior to assay. We show that soluble component(s) of the endoplasmic reticulum that are lost in the high-pH wash are required for GPI anchoring. We reconstituted the high-pH extract with high-pH-treated membranes and demonstrated restoration of activity. Size fractionation of the high-pH extract indicated that the active component(s) was 30–50kDa in size and was inactivated by iodoacetamide. Activity could also be restored by reconstituting the inactivated membranes with Escherichia coli-expressed, polyhistidine-tagged Leishmania mexicana GPI8 (GPI8-His; L. mexicana GPI8 is a soluble homologue of yeast and mammalian Gpi8p). No activity was seen when iodoacetamide-treated GPI8-His was used; however, GPI8-His could restore activity to iodoacetamide-treated membranes. Antibodies raised against L. mexicana GPI8 detected a protein of approx. 38kDa in an immunoblot of the high-pH extract of trypanosome membranes. Our data indicate (1) that trypanosome GPI8 is a soluble lumenal protein, (2) that the interaction between GPI8 and other putative components of the transamidase may be dynamic, and (3) that GPI anchoring can be biochemically reconstituted using an isolated transamidase component.

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