Plasmid weight

LPEI was used for DNA complexation. Novel two triblock copolymers, LPEI-b-PEG-b-LPEI (M 2100-3400-2100 and 4000-3400-4000) (Scheme 60(a)), were shown to condense plasmid DNA effectively to give polymer/DNA complexes (poly-plexes) of small sizes (<100nm) and moderate -potentials ( + 10mV) at polymer/plasmid weight ratios >1.5/1. These polyplexes efficiently transfected COS-7 cells and primary bovine endothelial cells in vitro and are a novel class of nonviral gene delivery systems.Lipopolymers were prepared as a potential candidate for constmcting tailored model cell membranes. A lipid triflate was used as initiator for CROP of hydrophilic monomers, MeOZO and EtOZO, to produce an amphiphilic polymer as the model (Scheme 60(b)). 

This resistance, inducible by low concentrations of dalbaheptides, is plasmid mediated and is transferable. Concomitant with the induction of resistance is the appearance or increased expression of a protein having a molecular weight of either 39,500 or 39,000. The enzymatic activity of this material has been postulated (112). Although the mechanism of resistance induction by dalbaheptides is unknown, different dalhabaheptides have different induction capacity. Vancomycin (39) is the most powerful inducer teicoplanin is a very weak inducer. 

Bacteria produce chromosomady and R-plasmid (resistance factor) mediated P-lactamases. The plasmid-mediated enzymes can cross interspecific and intergeneric boundaries. This transfer of resistance via plasmid transfer between strains and even species has enhanced the problems of P-lactam antibiotic resistance. Many species previously controded by P-lactam antibiotics are now resistant. The chromosomal P-lactamases are species specific, but can be broadly classified by substrate profile, sensitivity to inhibitors, analytical isoelectric focusing, immunological studies, and molecular weight deterrnination. Individual enzymes may inactivate primarily penicillins, cephalosporins, or both, and the substrate specificity predeterrnines the antibiotic resistance of the producing strain. Some P-lactamases are produced only in the presence of the P-lactam antibiotic (inducible) and others are produced continuously (constitutive). 

Quantitative entrapment of vaccines into small (up to about 200 nm diameter) liposomes in the absence of microfluidization (which can damage DNA and other labile materials when extensive) can be carried out by a novel one-step method (7) as follows SUVs (e.g., cationic) prepared as in section Preparation of Small Unilamellar Vesicles are mixed with sucrose to give a range of sucrose-to-lipid weight/weight ratio of 1.0 to 5.0 and the appropriate amount of plasmid DNA (e.g., 10-500 pg) and/or protein (e.g., up to 1 mg). The mixture is then rapidly frozen and subjected to dehydration by freeze-drying, followed by rehydration as in section Preparation of Vaccine-Containing Dehydration-Rehydration Vesicles. ... 

Nucleic acids can also be solubilized in reverse micelles, including ribosomes and plasmids, (Imre and Luisi, 1982 Palazzo and Luisi, 1992 Pietrini and Luisi, 2002 2004 Ousfuri et al, 2005), which also gives rise to a series of interesting structural and thermodynamic questions. In particular, high-molecular-weight... 

The common strategy is to entrap into the aqueous core of liposomes all the ingredients for the in vitro protein expression i.e., the gene for the GFP (a plasmid), an RNA polymerase, ribosomes, and all the low-molecular-weight components (amino acids, ATP, etc.) needed for protein expression. 

A. General description Intron A (interferon alfa-2b recombinant) is a recombi-nantly derived water-soluble protein with a molecular weight of 19.3 kDa. It is obtained from the bacterial fermentation of a strain of Escherichia coli bearing a genetically engineered plasmid containing an interferon alfa-2b gene from human leukocytes. 

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