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The study of bacteriocins is one of the most relevant areas of research. This is due to the increase in the number of pathogenic microorganisms resistant to antibiotics. The bacteriocins of lactic acid bacteria have the most common application because of their safety in use. To assess the antimicrobial potential of bacteriocins of lactic acid bacteria and the possibilities for their further use, this study deals with the intensity of bacteriocin production by strains of lactic acid bacteria, the minimal inhibitory concentration of bacteriocins produced by these strains with respect to E. coli В-6954, as well as the antimicrobial activity of the produced bacteriocins with respect to some strains of pathogenic microorganisms. This work was carried out on the basis of the Kemerovo Technological Institute of Food Industry (Russia). The study objects were strains of microorganisms Lactobacillus delbrueckii B2455, Lactobacillus paracasei B2430, Lactobacillus plantarum B884. Biomass concentration was determined by spectrophotometric method. Study of antimicrobial activity in relation to a number of pathogenic strains was carried out in a culture fluid by optical density, and also by a disk-diffusion test. As a result, the maximum productivity value, characterizing the intensity of bacteriocin production, was observed for strain B884. However, the quality of bacteriocin (antimicrobial activity relative to the E. coli strain) with a lower productivity is higher for strain B2430. The minimum inhibitory concentration for the strains studied was: B2430 - 1.0 106 CFU/ml, B884 -1.0 108 CFU/ml, B2455 - 1.0 107 CFU/ml. The best indicator of the minimum inhibitory concentration was observed for strain B2430. Thus the strain B2430 had the greatest antimicrobial activity, it had an inhibitory effect on 12 test cultures: Escherichia coli, Alcaligenes faecalis, Candida albicans, Pseudomonas libanensis, Staphylococcus warneri, Erwinia aphidicola, Microbacterium foliorum, Bacillus licheniformis, Serratia plymuthica, Erwinia aphidicola, Bacillus endophyticus, Leuconostoc mesenteroides. Thus, among the test Lactobacillus strains, the strain of Lactobacillus paracasei B2430 is promising for further study.

In this paper, on the basis of the conducted research, the technology of foaming agent for sports nutrition from pig blood has beendeveloped. The formulae of presented options of products are given. Physico-chemical properties and microbiological characteristics have been studied. The process of obtaining a foaming agent consists of the following operations: blood collection, stabilization of blood, cooling of stabilized blood, and separation of plasma and eritrocitarnae mass, collection of plasma, freeze-drying, packaging, storage. To stabilize whole blood, it is advisable to use a 0.75% solution of Na3PO4 and 4% solution of Na3C6 H5O7 in the ratio of 1:1 or a 0.75% solution of Na3PO4 and 4% solution of Na3C6 H5O7, in the ratio of 2:3. The stabilizer to blood ratio is 1:10. The separation of stabilized blood is made when the separation factor Fr =2000. Blood plasma drying is carried out using a sublimation method. The total process lasts for 240 minutes at the temperature of 40C. The developed technology allows obtaining a finished product that meets the requirements of SanRaN for microbiological characteristics and the content of toxic elements. The product has a high content of essential amino acids and can be recommended as a protein component of the protein cocktails for sports nutrition. Production of protein foam concentrates with a high content of protein from secondary raw materials (pig blood plasma) is a good way to improve the quality of functional foods using a low cost process.

Purpose: To report the interim results from a study comparing the efficacy, toxicity, and cosmesis of breast-conserving treatment with accelerated partial breast irradiation (APBI) or whole breast irradiation (WBI) using 3-dimensional conformal external beam radiation therapy (3D-CRT)., Methods and Materials: 102 patients with early-stage breast cancer who underwent breast-conserving surgery were randomized to receive either WBI (n=51) or APBI (n=51). In the WBI arm, 48 Gy was delivered to the whole breast in daily fractions of 2 Gy, with or without additional 10 Gy to the tumor bed. In the APBI arm, patients received 37.5 Gy in 3.75 Gy per fraction delivered twice daily. Toxicity results were scored according to the Radiation Therapy Oncology Group Common Toxicity Criteria. Skin elasticity was measured using a dedicated device (Multi-Skin-Test-Center MC-750-B2, CKelectronic-GmbH). Cosmetic results were assessed by the physician and the patients as good/excellent, regular, or poor., Results: The median follow-up time was 5 years. No local recurrences were observed. No significant differences in survival rates were found. APBI reduced acute side effects and radiation doses to healthy tissues compared with WBI (P<.01). Late skin toxicity was no worse than grade 2 in either group, without significant differences between the 2 groups. In the ipsilateral breast, the areas that received the highest doses (ie, the boost or quadrant) showed the greatest loss of elasticity. WBI resulted in a greater loss of elasticity in the high-dose area compared with APBI (P<.05). Physician assessment showed that >75% of patients in the APBI arm had excellent or good cosmesis, and these outcomes appear to be stable over time. The percentage of patients with excellent/good cosmetic results was similar in both groups., Conclusions: APBI delivered by 3D-CRT to the tumor bed for a selected group of early-stage breast cancer patients produces 5-year results similar to those achieved with conventional WBI., (Copyright © 2013 Elsevier Inc. All rights reserved.)

N-carbamoyl-amino-acid amidohydrolase (also known as N-carbamoylase) is the stereospecific enzyme responsible for the chirality of the D- or L-amino acid obtained in the "Hydantoinase Process." This process is based on the dynamic kinetic resolution of D,L-5-monosubstituted hydantoins. In this work, we have demonstrated the capability of a recombinant L-N-carbamoylase from the thermophilic bacterium Geobacillus stearothermophilus CECT43 (BsLcar) to hydrolyze N-acetyl and N-formyl-L-amino acids as well as the known N-carbamoyl-L-amino acids, thus proving its substrate promiscuity. BsLcar showed faster hydrolysis for N-formyl-L-amino acids than for N-carbamoyl and N-acetyl-L-derivatives, with a catalytic efficiency (k(cat)/K(m)) of 8.58 x 10(5), 1.83 x 10(4), and 1.78 x 10(3) (s(-1) M(-1)), respectively, for the three precursors of L-methionine. Optimum reaction conditions for BsLcar, using the three N-substituted-L-methionine substrates, were 65 degrees C and pH 7.5. In all three cases, the metal ions Co(2+), Mn(2+), and Ni(2+) greatly enhanced BsLcar activity, whereas metal-chelating agents inhibited it, showing that BsLcar is a metalloenzyme. The Co(2+)-dependent activity profile of the enzyme showed no detectable inhibition at high metal ion concentrations., ((c) 2010 American Institute of Chemical Engineers)

The N-succinylamino acid racemases (NSAAR) belong to the enolase superfamily and they are large homooctameric/hexameric species that require a divalent metal ion for activity. We describe the structure and stability of NSAAR from Geobacillus kaustophilus (GkNSAAR) in the absence and in the presence of Co(2+) by using hydrodynamic and spectroscopic techniques. The Co(2+), among other assayed divalent ions, provides the maximal enzymatic activity at physiological pH. The protein seems to be a tetramer with a rather elongated shape, as shown by AU experiments; this is further supported by the modeled structure, which keeps intact the largest tetrameric oligomerization interfaces observed in other homooctameric members of the family, but it does not maintain the octameric oligomerization interfaces. The native functional structure is mainly formed by alpha-helix, as suggested by FTIR and CD deconvoluted spectra, with similar percentages of structure to those observed in other protomers of the enolase superfamily. At low pH, the protein populates a molten-globule-like conformation. The GdmCl denaturation occurs through a monomeric intermediate, and thermal denaturation experiments indicate a high thermostability. The presence of the cofactor Co(2+) did alter slightly the secondary structure, but it did not modify substantially the stability of the protein. Thus, GkNSAAR is one of the few members of the enolase family whose conformational propensities and stability have been extensively characterized.

An N-carbamoyl-beta-alanine amidohydrolase of industrial interest from Agrobacterium tumefaciens C58 (beta car(At)) has been characterized. Beta car(At) is most active at 30 degrees C and pH 8.0 with N-carbamoyl-beta-alanine as a substrate. The purified enzyme is completely inactivated by the metal-chelating agent 8-hydroxyquinoline-5-sulfonic acid (HQSA), and activity is restored by the addition of divalent metal ions, such as Mn(2+), Ni(2+), and Co(2+). The native enzyme is a homodimer with a molecular mass of 90 kDa from pH 5.5 to 9.0. The enzyme has a broad substrate spectrum and hydrolyzes nonsubstituted N-carbamoyl-alpha-, -beta-, -gamma-, and -delta-amino acids, with the greatest catalytic efficiency for N-carbamoyl-beta-alanine. Beta car(At) also recognizes substrate analogues substituted with sulfonic and phosphonic acid groups to produce the beta-amino acids taurine and ciliatine, respectively. Beta car(At) is able to produce monosubstituted beta(2)- and beta(3)-amino acids, showing better catalytic efficiency (k(cat)/K(m)) for the production of the former. For both types of monosubstituted substrates, the enzyme hydrolyzes N-carbamoyl-beta-amino acids with a short aliphatic side chain better than those with aromatic rings. These properties make beta car(At) an outstanding candidate for application in the biotechnology industry.

Purpose: To assess the usefulness of oral glutamine to prevent radiochemotherapy-induced esophagitis in patients with lung cancer, and to determine the dosimetric parameter predictive of esophagitis., Methods and Materials: Seventy-five patients were enrolled; 34.7% received sequential radiochemotherapy, and 65.3% received concomitant radiochemotherapy. Every patient received prophylactic glutamine powder in doses of 10 g/8 h. Prescribed radiation doses were 45-50 Gy to planning target volume (PTV)1 (gross tumor volume plus wide margins) and 65-70 Gy to PTV2 (reduced margins). The primary endpoint was the incidence of Grade 2 or greater acute esophagitis., Results: No patient experienced glutamine intolerance or glutamine-related toxicity. Seventy-three percent of patients who received sequential chemotherapy and 49% of those who received concomitant chemotherapy did not present any form of esophagitis. V50 was the dosimetric parameter with better correlation between esophagitis and its duration. A V50 of or=2, which increased to 71% with a V50 of >30% (p = 0.0009)., Conclusions: The use of oral glutamine may have an important role in the prevention of esophageal complications of concomitant radiochemotherapy in lung cancer patients. However, randomized trials are needed to corroborate that effect. V50 is the dosimetric parameter with better correlation with esophagitis grade and duration.

Two recombinant reaction systems for the production of optically pure D-amino acids from different D,L-5-monosubstituted hydantoins were constructed. Each system contained three enzymes, two of which were D-hydantoinase and D-carbamoylase from Agrobacterium tumefaciens BQL9. The third enzyme was hydantoin racemase 1 for the first system and hydantoin racemase 2 for the second system, both from A. tumefaciens C58. Each system was formed by using a recombinant Escherichia coli strain with one plasmid harboring three genes coexpressed with one promoter in a polycistronic structure. The D-carbamoylase gene was cloned closest to the promoter in order to obtain the highest level of synthesis of the enzyme, thus avoiding intermediate accumulation, which decreases the reaction rate. Both systems were able to produce 100% conversion and 100% optically pure D-methionine, D-leucine, D-norleucine, D-norvaline, D-aminobutyric acid, D-valine, D-phenylalanine, D-tyrosine, and D-tryptophan from the corresponding hydantoin racemic mixture. For the production of almost all D-amino acids studied in this work, system 1 hydrolyzed the 5-monosubstituted hydantoins faster than system 2.