Polylysine
Mostrando 1-12 de 120 artigos, teses e dissertações.
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1. Antibacterial activity of polyvinyl alcohol (PVA)/ε-polylysine packaging films and the effect on longan fruit
Abstract Biodegradable and antimicrobial films via combing ε-polylysine (ε-PL) and polyvinyl alcohol (PVA) is a promising material for food packaging. We prepared the ε-PL/ PVA films with the ε-PL content of 0%, 1%, 3%, 5% and 7% (wt., relative to PVA) by casting method and their physical and chemical properties were characterized. SEM indicated the surf
Food Sci. Technol. Publicado em: 2020-12
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2. Agentes quelantes e poliaminas como grupos ionogênicos para a purificação de IgG humana por cromatografia / Chelating ligands and polyamines as ionogenic groups for human IgG purification by chromatography
Dentre os hemoderivados disponíveis comercialmente, as imunoglobulina do isotipo G (IgG) recebem destaque pelo seu uso em aplicações terapêuticas. Por esta razão são requeridas com elevado grau de pureza. Várias técnicas vêm sendo investigadas para a purificação de IgG a partir do soro ou plasma humano, desde a precipitação até métodos mais se
Publicado em: 2010
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3. Coupling of adenovirus to transferrin-polylysine/DNA complexes greatly enhances receptor-mediated gene delivery and expression of transfected genes.
We are developing efficient methods for gene transfer into tissue culture cells. We have previously shown that coupling of a chimeric adenovirus with polylysine allowed the construction of an adenovirus-polylysine-reporter-gene complex that transferred the transporter gene with great efficiency into HeLa cells. We have now explored simpler, biochemical means
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4. Influenza virus hemagglutinin HA-2 N-terminal fusogenic peptides augment gene transfer by transferrin-polylysine-DNA complexes: toward a synthetic virus-like gene-transfer vehicle.
Complexes containing plasmid DNA, transferrin-polylysine conjugates, and polylysine-conjugated peptides derived from the N-terminal sequence of the influenza virus hemagglutinin subunit HA-2 have been used for the transfer of luciferase or beta-galactosidase marker genes to K562 cells, HeLa cells, and BNL CL.2 hepatocytes. These DNA complexes mimic the entry
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5. Specific gene transfer mediated by lactosylated poly-L-lysine into hepatoma cells.
Plasmid DNA/glycosylated polylysine complexes were used to transfer in vitro a luciferase reporter gene into human hepatoma cells by a receptor-mediated endocytosis process. HepG2 cells which express a galactose specific membrane lectin were efficiently and selectively transfected with pSV2Luc/lactosylated polylysine complexes in a sugar dependent manner: i)
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6. Thermal denaturation of calf thymus DNA: existence of a GC-richer fraction
In 2.5 × 10−4M EDTA buffer, the derivative melting curve of calf thymus DNA shows a major band at 47° with a shoulder at about 54°. The fraction of melting area of this shoulder is about 13%. For reconstituted polylysine-calf thymus DNA complexes, in addition to the melting of free DNA regions at about 50° (Tm) there is another melting at about 106° (
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7. Polylysine domain of K-ras 4B protein is crucial for malignant transformation.
Previous studies have shown that posttranslational modifications are required for both oncogenic K-ras 4B protein membrane binding and transforming activity. In addition, Hancock et al. [Hancock, J. F., Patterson, H. & Marshall, C. J. (1990) Cell 63, 133-139] found that a polylysine domain contained at the C terminus of K-ras 4B was also absolutely essential
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8. Effects of Poly-l-Lysine on Infectious Viral Nucleic Acid
Infectious ribonucleic acids (IRNA) of Venezuelan equine encephalitis and Eastern equine encephalitis viruses were observed to form noninfectious complexes with a basic polyamino acid, poly-l-lysine. Original infectivity was recovered from the complexes by digestion of the polylysine with Pronase, and partial recovery was effected by treatment with sodium do
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9. Inhibition of leukemia cell proliferation by receptor-mediated uptake of c-myb antisense oligodeoxynucleotides.
Exposure of human leukemia HL-60 cells to an oligodeoxynucleotide complementary to an 18-base sequence (codons 2-7) of c-myb-encoded mRNA has previously been shown to result in inhibition of cell proliferation. Because HL-60 cells express high levels of transferrin receptor we adapted a DNA delivery system based on receptor-mediated endocytosis to introduce
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10. Adenovirus enhancement of transferrin-polylysine-mediated gene delivery.
Gene transfer may be accomplished by the receptor-mediated endocytosis pathway using transferrin-polylysine conjugates. For some target cells, however, gene transfer by this vector is extremely limited, despite the presence of the appropriate surface receptors, a phenomenon attributed to lysosomal degradation of endosome-internalized conjugate-DNA complexes.
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11. Polylysine-containing peptides, including the carboxyl-terminal segment of the human c-Ki-ras 2 protein, affect the activity of some key membrane enzymes.
Polylysine-containing peptides are found to affect membrane protein kinases, phosphatidylinositol kinases, and adenylate cyclase. Poly(L-lysine), poly(D-lysine), random copolymers of lysine and serine or lysine and alanine, and poly(L-ornithine) produced large increases in the in vitro phosphorylation of some membrane proteins present in Xenopus laevis oocyt
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12. Spin-label electron spin resonance studies on the interactions of lysine peptides with phospholipid membranes.
The interactions of lysine oligopeptides with dimyristoyl phosphatidylglycerol (DMPG) bilayer membranes were studied using spin-labeled lipids and electron spin resonance spectroscopy. Tetralysine and pentalysine were chosen as models for the basic amino acid clusters found in a variety of cytoplasmic membrane-associating proteins, and polylysine was chosen