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Query: UNIPROT:P00790 (PGA)
 2,475 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We prepared natto (fermented soybeans) mucilage containing poly-gamma-glutamic acid (gamma-PGA) from commercial natto. The effect of natto mucilage on calcium (Ca) solubility in vitro and in vivo was investigated. Ca solubility in vitro increased with an increase in the amount of natto mucilage, due to inhibition of the formation of an insoluble complex of Ca with phosphate by natto mucilage. Rats were fed with 5 g of soybean protein isolate, natto, mucilage-free natto, or natto mucilage diet for 1.5 h. Small intestinal contents were collected 2.5 h after ingestion. In the lower half of the small intestine, both the amount and the percentage of soluble Ca of intestinal contents were significantly higher (P < 0.001) in rats fed with natto mucilage diet than in those fed with the other diets. Natto mucilage also increased Ca solubility in vivo. These results suggested that gamma-PGA is responsible for the increasing effect of natto mucilage on Ca solubility.
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PMID:Natto mucilage containing poly-gamma-glutamic acid increases soluble calcium in the rat small intestine. 1133 Jun 62

This review article deals with the chemistry and biosynthesis of poly-(gamma-glutamic acid) (gamma-PGA) produced by various strains of Bacillus. Potential applications of gamma-PGA as thickener, cryoprotectant, humectant, drug carrier, biological adhesive, flocculant, or heavy metal absorbent, etc. with biodegradability in the fields of food, cosmetics, medicine and water treatments are also reviewed.
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PMID:The production of poly-(gamma-glutamic acid) from microorganisms and its various applications. 1149 75

We report the development of new bioactive coatings of biomaterials based on the alternate deposition of oppositely charged polyelectrolytes. We selected polylysine (PLL) and poly(glutamic acid) (PGA) for the polyelectrolytes and murine melanoma cells as a biological test model system. These cells respond specifically to a small peptide hormone, alpha-melanocortin, which is a potent stimulator of melanogenesis. We show that a synthetic alpha-melanocortin derivative, covalently coupled to PLL forming the outer layer of a multilayer film remains as biologically active as the free hormone. Furthermore, the long time activity of the hormone is maintained when embedded in multilayer architectures whereas its short time activity depends on integration depth. The embedding of bioactive molecules not only anchors them irreversibly on the biomaterial, but opens also the possibility to control their activity. In comparison to conventional coating methods, polyelectrolyte multilayers are easy to prepare and retain their biological activity after storage as dry material. These very flexible systems allow broad medical applications for implant and tissue engineering.
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PMID:Peptide hormone covalently bound to polyelectrolytes and embedded into multilayer architectures conserving full biological activity. 1171 34

gamma-Poly(glutamic acid) (gamma-PGA), which is produced by Bacillus subtilis, was sulfonated using 2-aminoethane-1-sulfonic acid (taurine) in the presence of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (WSC) to give sulfonated gamma-PGA (gamma-PGA-sulfonate). From (1)H NMR spectroscopy and IR spectroscopy, it was confirmed that taurine was introduced to the side chain of gamma-PGA via an amide linkage. By altering the synthetic conditions, it was possible to control the content of sulfonate in gamma-PGA-sulfonate. Anticoagulant activity was investigated in order to evaluate the biological activity of gamma-PGA-sulfonate by the Lee-White test. The clotting time was prolonged when the concentration of gamma-PGA-sulfonate on the degree of sulfonation was increased. It becomes clear that gamma-PGA-sulfonate is potentially useful for various medical applications, such as drug delivery, tissue engineering, and medical materials.
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PMID:Novel functional biodegradable polymer: synthesis and anticoagulant activity of poly(gamma-glutamic acid)sulfonate (gamma-PGA-sulfonate). 1179 75

In the course of gamma-poly (glutamic acid) gamma-PGA fermentation, metal ions K+, Mg2+, Fe3+, Ca2+, Mo6+, Mn2+, Co2+ and Zn2+ in the medium have certain effects on the synthesis of gamma-poly(glutamic acid). Excess or lack of K+, Mg2+ and Fe3+ results in reduced yield of gamma-PGA. It was found that the gamma-PGA synthesis by Bacillus licheniformis was promoted obviously by Ca2+ and Mo6+. Synthesis and stereochemical composition of gamma-PGA was greatly regulated by Mn2+. gamma-PGA was not produced without Mn2+ in medium, and with the increase of Zn2+ concentration the yield of gamma-PGA and the proportion of D-glutamic acid in the peptide increase. Regulative effect of Co2+ and Zn2+ was almost the same as that of Mn2+, thus the combination of Mn2+, Co2+ cannot enhance gamma-PGA synthesis and affect stereochemical composition of gamma-PGA. Based on the experimental date, an appropriate formulation of metal ions in the medium for gamma-PGA production was obtained.
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PMID:[Effects of metal ions on gamma-poly (glutamic acid) synthesis by Bacillus licheniformis]. 1191 Jul 70

The aim of this study was to develop new biocompatible coatings for bone implants by the alternating deposition of oppositely charged polyelectrolytes. Polyelectrolyte films were built up with different terminating layers on which SaOS-2 osteoblast-like cells and human periodontal ligament (PDL) cells were grown. The terminating layer was made of one of the following polyelectrolytes: poly(ethylene imine) (PEI), poly(sodium 4-styrenesulfonate) (PSS), poly(allylamine hydrochloride) (PAH), poly(L-glutamic acid) (PGA), or poly(L-lysine) (PLL). Cell adherence, viability, stability of osteoblast phenotype, and inflammatory response were studied. Adherence and viability were good on all terminating layers except the PEI-terminating layer, which was cytotoxic. Maintenance of osteoblast phenotype marker expression was observed on PSS- and PGA-terminating films for both cell types, whereas downregulation, associated with the induction of Interleukin-8 (IL-8) secretion, was detected on PEI and PAH for both cell types and on PLL for PDL cells. These results suggested a good biocompatibility of PSS- and PGA-ending films for PDL cells and of PSS-, PGA-, and PLL-terminating films for SaOS-2 cells. As a result, polyelectrolyte multilayer films could emerge as new alternatives for implant coatings.
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PMID:Viability, adhesion, and bone phenotype of osteoblast-like cells on polyelectrolyte multilayer films. 1194 25

The short-term interactions of chondrosarcoma cells with polyelectrolyte multilayer films built up by the alternate adsorption of poly(L-lysine) (PLL) and poly(L-glutamic acid) (PGA) was studied in the presence and in the absence of serum. The films and their interaction with serum proteins were first characterized by means of optical waveguide lightmode spectroscopy, quartz crystal microbalance, and zeta potential measurements. In a serum-containing medium, the detachment forces measured by the micropipet technique were about eight times smaller on PGA-ending than on PLL-ending films. For these latter ones, the adhesion force decreased when the film thickness increased. In a serum-free medium, the differences between the negative- and positive-ending films were enhanced: adhesion forces on PLL-ending films were 40-100% higher, whereas no cellular adherence was found on PGA-terminating films. PGA-ending films were found to prevent the adsorption of serum proteins, whereas important protein adsorption was always observed on PLL-ending films. These results show how cell interactions with polyelectrolyte films can be tuned by the type of the outermost layer, the presence of proteins, and the number of layers in the film.
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PMID:Cell interactions with polyelectrolyte multilayer films. 1242 53

Extensive spreading of liquid manure onto agricultural fields causes eutrophication of ground and surface water and also pollution of the atmosphere due to the high ammonium nitrogen content. A poly(gamma-glutamic acid) (PGA)-producing strain of Bacillus licheniformis was isolated in this study and investigated for its ability to reduce the ammonium nitrogen by converting ammonium into biomass and PGA as depot forms of nitrogen. In batch cultivations swine manure and an optimized mineral salts medium were used for PGA production. For example the cultivation of B. licheniformis strain S2 in liquid manure, which was modified by adding of 18 g citrate and 80 g glycerol l(-1) and exhibited a carbon to nitrogen ratio of 15.5:1, led to severe reduction of the ammonium content from 2.83 to 0.1 g x l(-1) and to the production of 0.16 g PGA and 7.5 g cell dry mass l(-1) within 410 h. Approximately 28% (w/w) of the total nitrogen was converted into cellular biomass, whereas 0.1% (w/w) was used for the production of PGA. In addition, approximately 33% (w/v) of the original ammonium was lost by stripping.
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PMID:Conversion of the nitrogen content in liquid manure into biomass and polyglutamic acid by a newly isolated strain of Bacillus licheniformis. 1258 95

Poly(glutamic acid) (PGA) is a water-soluble, biodegradable biopolymer that is produced by microbial fermentation. Recent research has shown that PGA can be used in drug delivery applications for the controlled release of paclitaxel (Taxol) in cancer treatment. A fundamental understanding of the key fermentation parameters is necessary to optimize the production and molecular weight characteristics of poly(glutamic acid) by Bacillus subtilis for paclitaxel and other applications of pharmaceuticals for controlled release. Because of its high molecular weight, PGA fermentation broths exhibit non-Newtonian rheology. In this article we present experimental results on the batch fermentation kinetics of PGA production, mass transfer of oxygen, specific oxygen uptake rate, broth rheology, and molecular weight characterization of the PGA biopolymer.
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PMID:Rheology, oxygen transfer, and molecular weight characteristics of poly(glutamic acid) fermentation by Bacillus subtilis. 1259 56

Highly water-soluble glycopolymers with poly(alpha-L-glutamic acid) (PGA) backbones carrying multivalent sialyl oligosaccharides units were chemoenzymatically synthesized as polymeric inhibitors of infection by human influenza viruses. p-Aminophenyl disaccharide glycosides were coupled with gamma-carboxyl groups of PGA side chains and enzymatically converted to Neu5Acalpha2-3Galbeta1-4GlcNAcbeta-, Neu5Acalpha2-6Galbeta1-4GlcNAcbeta-, Neu5Acalpha2-3Galbeta1-3GalNAcalpha-, and Neu5Acalpha2-3Galbeta1-3GalNAcbeta- units, respectively, by alpha2,3- or alpha2,6-sialytransferases. The glycopolymers synthesized were used for neutralization of human influenza A and B virus infection as assessed by measurement of the degree of cytopathic inhibitory effect in virus-infected MDCK cells. Among the glycopolymers tested, alpha2,6-sialo-PGA with a high molecular weight (260 kDa) most significantly inhibited infection by an influenza A virus, strain A/Memphis/1/71 (H3N2), which predominantly binds to alpha2-6 Neu5Ac residue. The alpha2,6-sialo-PGA also inhibited infection by an influenza B virus, B/Lee/40. The binding preference of viruses to terminal sialic acids was affected by core determinants of the sugar chain, Galbeta1-4GlcNAcbeta- or Galbeta1-3GalNAcalpha/beta- units. Inhibition of infection by viruses was remarkably enhanced by increasing the molecular weight and sialic acid content of glycopolymers.
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PMID:Chemoenzymatic synthesis and application of glycopolymers containing multivalent sialyloligosaccharides with a poly(L-glutamic acid) backbone for inhibition of infection by influenza viruses. 1262 82


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