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Sample records for bacterial protein meal

  1. Bacterial protein meal in diets for pigs and minks

    DEFF Research Database (Denmark)

    Hellwing, Anne Louise Frydendahl; Tauson, Anne-Helene; Skrede, Anders;

    2007-01-01

    The effect of increasing the dietary content of bacterial protein meal (BPM) on protein turnover rate, and on nucleic acid and creatinine metabolism in growing minks and pigs was investigated in two experiments. In each experiment, 16 animals were allocated to four experimental diets. The diets...... containing no BPM served as controls, i.e. for minks diet M1, for pigs P1; the experimental diets contained increasing levels of BPM to replace fish meal (minks) or soybean meal (pigs), so that up to 17% (P2), 20% (M2), 35% (P3), 40% (M3), 52% (P4), and 60% (M4) of digestible N was BPM derived. Protein...... turnover rate was measured by means of the end-product method using [15N]glycine as tracer and urinary nitrogen as end-product. In minks, protein flux, synthesis, and breakdown increased significantly with increasing dietary BPM. In pigs, diet had no observed effect on protein turnover rate. The intake...

  2. Bacterial protein meal in diets for growing pigs

    DEFF Research Database (Denmark)

    Hellwing, Anne Louise Frydendahl; Tauson, Anne-Helene; Kjos, N.P.

    2007-01-01

    blocks according to age. One pig from each litter was fed one of the four experimental diets. Soya-bean meal was replaced with BPM on the basis of digestible protein, and the BPM contents in the four diets were 0% (BP0), 5% (BP5), 10% (BP10) and 15% (BP15), corresponding to 0%, 17%, 35% and 52...

  3. Effect of bacterial protein meal on protein and energy metabolism in growing chickens

    DEFF Research Database (Denmark)

    Hellwing, Anne Louise Frydendahl; Tauson, Anne-Helene; Skrede, Anders

    2006-01-01

    This experiment investigates the effect of increasing the dietary content of bacterial protein meal (BPM) on the protein and energy metabolism, and carcass chemical composition of growing chickens. Seventy-two Ross male chickens were allocated to four diets, each in three replicates with 0% (D0), 2......% (D2), 4% D4), and 6% BPM (D6), BPM providing up to 20% of total dietary N. Five balance experiments were conducted when the chickens were 3-7, 10-14, 17-21, 23-27, and 30-34 days old. During the same periods, 22-h respiration experiments (indirect calorimetry) were performed with troups of 6 chickens...

  4. Excretion of purine base derivatives after intake of bacterial protein meal in pigs

    DEFF Research Database (Denmark)

    Hellwing, Anne Louise Frydendahl; Tauson, Anne-Helene; Skrede, A.

    2007-01-01

    Bacterial protein meal has a high content ofprotein but also of RNA and DNA. Sixteen barrows were allocated to four diets containing increasing levels of bacterial protein meal (BPM), from weaning to 80 kg live weight, to evaluate whether the RNA and DNA contents of BPM influenced the retention...... of nitrogen. It was hypothesised that an increased intake of RNA and DNA would lead to an increased urinary excretion of purine base derivatives and increased plasma concentrations. Retention of nitrogen was unaffected by dietary content of BPM (P=0.08) and the urinary excretion of purine base derivatives...... increased with increasing dietary content of BPM. No differences in fasting plasma concentration of uric acid, xanthine and hypoxanthine were observed. It can therefore be concluded that increasing levels of dietary BPM maintained protein accretion and led to changes in excretion of purine detrivatices...

  5. Blood parameters in growing pigs fed increasing levels of bacterial protein meal

    Directory of Open Access Journals (Sweden)

    Tauson Anne-Helene

    2007-11-01

    Full Text Available Abstract The experiment investigated the effects of increasing dietary levels of bacterial protein meal (BPM on various blood parameters reflecting protein and fat metabolism, liver function, and purine base metabolism in growing pigs. Sixteen barrows were allocated to four different experimental diets. The control diet was based on soybean meal. In the other three diets soybean meal was replaced with increasing levels of BPM, approximately 17%, 35%, and 50% of the nitrogen being derived from BPM. Blood samples from the jugular vein were taken when the body weights of the pigs were approximately 10 kg, 21 kg, 45 kg, and 77 kg. The blood parameters reflecting fat metabolism and liver function were not affected by diet. Both the plasma albumin and uric acid concentrations tended to decrease (P = 0.07 and 0.01, respectively with increasing dietary BPM content, whereas the plasma glucose concentration tended to increase (P = 0.07 with increasing dietary BPM content. It was concluded that up to 50% of the nitrogen could be derived from BPM without affecting metabolic function, as reflected in the measured blood parameters.

  6. Blood parameters in growing pigs fed increasing levels of bacterial protein meal

    DEFF Research Database (Denmark)

    Hellwing, Anne Louise Frydendahl; Tauson, Anne-Helene; Skrede, Anders

    2007-01-01

    The experiment investigated the effects of increasing dietary levels of bacterial protein meal (BPM) on various blood parameters reflecting protein and fat metabolism, liver function, and purine base metabolism in growing pigs. Sixteen barrows were allocated to four different experimental diets......, 45 kg, and 77 kg. The blood parameters reflecting fat metabolism and liver funtion were not affected by diet. Both the plasma albumin and uric acid concentrations tended to decrease (P = 0.07 and 0.01, respectively) with increasing dietary BPM content, whereas the plasma glucose concentration tended...... to increase (P = 0.07) with increasing dietary BPM content. It was concluded that up to 50% of the nitrogen could be derived from BPM without affecting metabolic function, as reflected in the measured blood parameters....

  7. Nitrogen and energy balance in growing mink (Mustela vison) fed different levels of bacterial protein meal produced with natural gas

    DEFF Research Database (Denmark)

    Hellwing, Anne Louise Frydendahl; Tauson, Anne-Helene; Ahlstrøm, Øystein;

    2005-01-01

    The objective of this study was to estimate the effect of increasing the dietary content of bacterial protein meal (BPM) on energy and protein metabolism in growing mink kits. Sixteen male mink kits of the standard brown genotype were randomly fed one of four diets: A control (Diet III) and 60.......7% on Diet I to 26.6% on Diet IV, and oxidation of fat increased from 53.8% on Diet I to 63.5% Diet IV. In conclusion, protein and energy metabolism remained unaffected when up to 40% of DN was derived from BPM....

  8. Effect of bacterial protein meal grown on natural gas on growth performance and carcass traits of pigs

    Directory of Open Access Journals (Sweden)

    Anders Skrede

    2010-01-01

    Full Text Available Bacterial protein meal (BPM, a new protein feedstuff produced by bacteria (Methylococcus capsulatus, Alcaligenes acidovorans,Bacillus brevis and Bacillus firmus grown on natural gas, was evaluated as a protein source for pigs. Twogrowth trials were conducted, one with growing-finishing pigs and one with pigs from weaning until slaughter. In Exp. 1,18 pigs fed restrictively (26.0 and 109.4 kg initial and final weight were used to determine the effect of dietary inclusionof BPM (0, 60, or 120 g kg-1, replacing protein from soybean meal on growth performance and carcass traits. Adding60 and 120 g kg-1 BPM to diets reduced (P on growth performance during the finishing or overall periods. Both levels of BPM improved amino acid and lysine utilization(P contrast, both levels of BPM tended to increase carcass meatiness. In Exp. 2, 48 pigs (11.4 and 107.2 kg initial andfinal weight were used to evaluate increasing levels of BPM (0, 50, 100, or 150 g kg –1 on growth performance and carcasstraits from weaning at 34.5 days of age until slaughter. Bacterial protein meal reduced ADG (linear P the period from weaning until five weeks post weaning and during the period from weaning until slaughter. Increasinglevels of BPM tended to increase overall feed/gain. Also, BPM increased backfat firmness (linear P percent carcass lean (linear P fat area in cutlet (linear P with the control. In conclusion, up to 120 g kg –1 BPM in diets for pigs from 26 kg live weight until slaughter hadno adverse effect on overall growth performance or carcass lean or fat content. Up to 150 g kg –1 BPM to diets for pigsfrom weaning until slaughter reduced growth rates during the piglet period and increased carcass fat content due tomarginal dietary lysine levels. Bacterial protein meal gave a dose dependent improvement in the utilization of total aminoacids and lysine and the quality of back fat determined as fat firmness and fat color.

  9. Enzyme assisted protein extraction from rapeseed, soybean, and microalgae meals

    NARCIS (Netherlands)

    Sari, Y.W.; Bruins, M.E.; Sanders, J.P.M.

    2013-01-01

    Oilseed meals that are by-products from oil production are potential resources for protein. The aim of this work is to investigate the use of enzymes in assisting in the extraction of protein from different oilseed meals, namely rapeseed, soybean, and microalgae meals. In addition, microalgae withou

  10. Protein fractionation byproduct from canola meal for dairy cattle.

    Science.gov (United States)

    Heendeniya, R G; Christensen, D A; Maenz, D D; McKinnon, J J; Yu, P

    2012-08-01

    Fiber-protein is a byproduct arising from a process for fractionating high-quality protein from canola meal. The objective of this study was to evaluate the fiber-protein fraction by examining the chemical profiles, rumen degradation, and intestinal digestive characteristics and determining the nutritive value of the fiber-protein fraction as dietary components for dairy cattle in comparison with commercial canola meal and soybean meal. Available energy values were estimated based on National Research Council guidelines, whereas total true protein content potentially absorbable in the small intestine (DVE) were predicted using the predicted DVE/degraded protein balance (OEB) model. The results show that fiber-protein was a highly fibrous material [neutral detergent fiber (NDF): 556; acid detergent fiber (ADF): 463; acid detergent lignin: 241 g/kg of dry matter (DM)] compared with canola meal (NDF: 254; ADF: 212; acid detergent lignin: 90 g/kg of DM) due to the presence of a higher level of seed hulls in fiber-protein. Compared with canola meal, fiber-protein contained 90 g/kg of DM less crude protein (CP), 25% of which consisted of undegradable acid detergent-insoluble CP. Most of the ruminally undegradable nutrient components present in canola meal appeared to be concentrated into fiber-protein during the manufacturing process and, as a result, fiber-protein showed a consistently lower effective degradability of DM, organic matter, CP, NDF, and ADF compared with both canola meal and soybean meal. Available energy content in fiber-protein contained two-thirds of that of canola meal. The DVE was one-third that of soybean meal and one-fifth that of canola meal [DVE value: 58 vs. 180 (soybean) and 291 g/kg of DM (canola meal)]. The OEB value of fiber protein was positive and about half of that of soybean and canola meal [OEB value: 74 vs. 162 (soybean) and 137 g/kg of DM (canola meal)]. Fiber-protein can be considered as a secondary source of protein in ruminant feed.

  11. Performance of lambs fed alternative protein sources to soybean meal

    Directory of Open Access Journals (Sweden)

    Felipe José Lins Alves

    2016-04-01

    Full Text Available ABSTRACT The objective of this study was to evaluate the effect of alternative protein sources (castor bean cake, sunflower cake, and sunflower seed to soybean meal on the intake and performance of 40 lambs, initially weighing 19.8±1.84 kg, fed diets based on Tifton grass hay. The experimental design was completely randomized blocks. There were no differences in the nutrient intake of castor bean diets compared with soybean meal. The intake of nutrients in the sunflower cake and sunflower seed diets was decreased compared with soybean meal. The apparent digestibility coefficients of dry matter, organic matter, crude protein, and neutral detergent fiber of sunflower cake and sunflower seed diets were decreased compared with soybean meal. The average daily weight gain of animals fed the castor bean diet (0.190 kg was not different from that of the animals fed the soybean meal diet (0.217 kg. The sunflower cake and sunflower seed diets provided less weight gain (0.171 and 0.135 kg d-1, respectively than soybean meal due to the lower nutrient intake. The hot carcass yield and true yield were not affected by the protein sources. The neck, ribs, and ham weights were similar in lambs fed soybean meal and castor bean cake diets. It is recommended to use castor bean as an alternative protein source in the diet of lambs.

  12. Comparison of the adhesive performances of soy meal, water washed meal fractions, and protein isolates

    Science.gov (United States)

    Adhesive bonding of wood plays an increasing role in the forest products industry and is a key factor for efficiently utilizing timber and other lignocellulosic resources. In this work, we obtained five soy meal products through commercial sources or in-house preparations. The protein content was 49...

  13. Pea protein concentrate as a substitute for fish meal protein in sea bass diet

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    E. Badini

    2010-01-01

    Full Text Available Pea seeds, even if lower in protein than oilseed meals, have been shown to successfully replace moderate amounts of fish meal protein in diets for carnivorous fish species (Kaushik et al., 1993, Gouveia and Davies, 2000. A further processing of such pulses provides concentrated protein products which look very promising as fish meal substitutes in aquafeeds (Thiessen et al., 2003. The aim of the present study was to evaluate nutrient digestibility, growth response, nutrient and energy retention efficiencies and whole body composition of sea bass (Dicentrarchus labrax, L. fed complete diets in which a pea protein concentrate (PPC was used to replace graded levels of fish meal protein.

  14. Meals based on vegetable protein sources (beans and peas) are more satiating than meals based on animal protein sources (veal and pork) - a randomized cross-over meal test study

    DEFF Research Database (Denmark)

    Kristensen, Marlene Dahlwad; Bendsen, Nathalie Tommerup; Christensen, Sheena M

    2016-01-01

    on appetite regulation. OBJECTIVE: To examine whether meals based on vegetable protein sources (beans/peas) are comparable to meals based on animal protein sources (veal/pork) regarding meal-induced appetite sensations. DESIGN: In total, 43 healthy, normal-weight, young men completed this randomized, double......-blind, placebo-controlled, three-way, cross-over meal test. The meals (all 3.5 MJ, 28 energy-% (E%) fat) were either high protein based on veal and pork meat, HP-Meat (19 E% protein, 53 E% carbohydrate, 6 g fiber/100 g); high protein based on legumes (beans and peas), HP-Legume (19 E% protein, 53 E% carbohydrate...

  15. Fermentation of rapeseed meal, sunflower meal and faba beans in combination with wheat bran increases solubility of protein and phosphorus

    DEFF Research Database (Denmark)

    Poulsen, Hanne Damgaard; Blaabjerg, Karoline

    2017-01-01

    and solubilizing protein and phytate. Herein, solubilization of protein, N and P was investigated when increasing ratios of wheat bran were fermented with rapeseed meal (RSM), sunflower meal (SFM), faba beans (FB) or a combination of these (RSM/SFM/FB). RESULTS Protein, N and P solubility was greater, for all...... or with wheat bran uncovers a potential for increased protein and P digestibility and thereby reduced N and P excretion from pigs and poultry. © 2016 Society of Chemical Industry...

  16. Physical distribution and characteristics of meat & bone meal protein

    Science.gov (United States)

    Meat & bone meal (MBM) is a high-protein commodity produced by the rendering of fat from unmarketable animal tissue. Concerns related to bovine spongiform encephalopathy have progressively restricted MBM’s conventional use as a feed ingredient. Consequently, significant attention has focused on th...

  17. PROTEIN OF MEAT AND BONE MEAL FOR PIGS

    Directory of Open Access Journals (Sweden)

    Patieva S. V.

    2015-09-01

    Full Text Available The modern requirements of intergovernmental standards to the quality and safety of livestock produce provide for the use of highly productive animals capable under small expenses to produce more the high quality produce. In particular, at the formation of meat productivity at pigs the great significance has an achievement of optimal digestion and assimilability of consumed fodder means. In the connection, the study of digestion of meat and bone meal from slaughterhouse wastes of cattle (MCM and poultry (MCBM presents the scientific interest. In the fodder experience on the growing pigs with the fistula of iliac intestines there was investigated the digestion of two types of meat and bone meal from slaughterhouse wastes of cattle (MCM and poultry (MKBM. The iliac accessibility of amino acids of meat and bone meal found itself too low: 49,3 % - 69,3 %. The accessibility of general protein reliably did not differ from the average accessibility on main amino acids - 61,5 %. To count the real iliac accessibility of raw protein and amino acids of meat and bone meal there was determined an endogenous emission of these substances on the casein diet. The real iliac accessibility of protein and individual amino acids did not leave the limits in 73% on МCM and 69% - on МCBМ. The accessibility of lysine, leucine and isoleucine MCBM is reliably higher than the same in MCM (P

  18. On rapeseed meals. Part XXVI. Some remarks on the biological value of rapeseed meal proteins after silage.

    Science.gov (United States)

    Borowska, J; Cichon, R; Kozłowska, H; Rutkowski

    1978-01-01

    The influence of propionic bacteria on the biological value of potato-rapeseed meal protein ensilage was investigated. The inoculation of the ensilage with Propionibacterium Petersoni T 112 led to the reduction of the content of goitrogenous compounds (isothiocyanates and oxazolidinethiones) and to an increase of the nutritive value (NPU, PER) of the rapeseed protein. The increase of the protein value is greater by the application of propionic bacteria than by toasting of rapeseed meal.

  19. A study on the meat and bone meal and poultry by-product meal as protein substitutes of fish meal in practical diets for Litopenaeus vannamei juveniles

    Science.gov (United States)

    Zhu, Wei; Mai, Kangsen; Zhang, Baigang; Wang, Fuzhen; Yu, Yu

    2004-10-01

    A study was conducted to evaluate the effects of meat and bone meal (MBM) and poultry by-product meal (PBM) as the replacement of fish meal in the diets on the growth performance, survival and apparent digestibility coefficients (ADC) of Litopenaeus vannamei. The basal diets were formulated with 22% fish meal and other ingredients which provided about 40% protein and 9% lipid in the diet. The experimental diets included MBM or PBM to replace 0, 20%, 40%, 60% and 80% of total fish meal respectively. All diets were iso-nitrogenous and isocaloric in gross terms. The results showed that there were no significant differences (Pτ;0.05) in growth performance and ADC among the treatments fed with the diets in which 0 60% fish meal had been replaced with MBM, while the percent weight gain (WG, %), body length gain (BLG, %) and ADC significantly decreased when the MBM was up to 80% of the fish meal. There were no significant differences (Pτ;0.05) in growth performance and ADC among all the treatments fed with the diets in which 0 80% fish meal had been replaced with PBM.

  20. A Study on the Meat and Bone Meal and Poultry By-product Meal as Protein Substitutes of Fish Meal in Practical Diets for Litopenaeus vannamei Juveniles

    Institute of Scientific and Technical Information of China (English)

    ZHU Wei; MAI Kangsen; ZHANG Baigang; WANG Fuzhen; YU Yu

    2004-01-01

    A study was conducted to evaluate the effects of meat and bone meal(MBM)and poultry by-product meal(PBM)as the replacement of fish meal in the diets on the growth performance, survival and apparent digestibility coefficients(ADC)of Litopenaeus vannamei. The basal diets were formulated with 22% fish meal and other ingredients which provided about 40% protein and 9% lipid in the diet. The experimental diets included MBM or PBM to replace 0, 20%, 40%, 60% and 80% of total fish meal respectively. All diets were iso-nitrogenous and isocaloric in gross terms. The results showed that there were no significant differences(P>0.05)in growth performance and ADC among the treatments fed with the diets in which 0-60% fish meal had been replaced with MBM, while the percent weight gain(WG,%), body length gain(BLG,%)and ADC significantly decreased when the MBM was up to 80% of the fish meal. There were no significant differences(P>0.05)in growth performance and ADC among all the treatments fed with the diets in which 0-80% fish meal had been replaced with PBM.

  1. Bacterial Ice Crystal Controlling Proteins

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    Janet S. H. Lorv

    2014-01-01

    Full Text Available Across the world, many ice active bacteria utilize ice crystal controlling proteins for aid in freezing tolerance at subzero temperatures. Ice crystal controlling proteins include both antifreeze and ice nucleation proteins. Antifreeze proteins minimize freezing damage by inhibiting growth of large ice crystals, while ice nucleation proteins induce formation of embryonic ice crystals. Although both protein classes have differing functions, these proteins use the same ice binding mechanisms. Rather than direct binding, it is probable that these protein classes create an ice surface prior to ice crystal surface adsorption. Function is differentiated by molecular size of the protein. This paper reviews the similar and different aspects of bacterial antifreeze and ice nucleation proteins, the role of these proteins in freezing tolerance, prevalence of these proteins in psychrophiles, and current mechanisms of protein-ice interactions.

  2. [Chemical and biological characterization of meal and protein isolates from pumpkin seed (Cucurbita moschata)].

    Science.gov (United States)

    Salgado, J M; Takashima, M K

    1992-12-01

    The present study was carried out in order to check through chemical and biological analyses the nutritional characteristics of pumpkin seed, its delipidized meal and its proteic concentrate, considering its availability, nutritional potential, facility for production in poor soils and the need for new food resources. Another objective was to complement the amino acid pattern of pumpkin with others protein sources for human consumption. The results obtained indicate that: Raw pumpkin seed meal has a proteic values of 37.6% and the delipidized meal 68.8%; The PER values for raw seed meal and delipidized meal were 2.26 and 1.65, respectively; The chemical composition revealed that the delipized pumpkin seed meal was limited in threonine (66.8%); The isolate and seed meal proteins were both complemented with lysine and with cowpea bean meal; Whole pumpkin seed meal obtained from variety Caravelle is a good caloric material (approximately 568 cal/100 g).

  3. Replacement of Soybean Meal with Animal Origin Protein Meals Improved Ramoplanin A2 Production by Actinoplanes sp. ATCC 33076.

    Science.gov (United States)

    Erkan, Deniz; Kayali, Hulya Ayar

    2016-09-01

    Ramoplanin A2 is the last resort antibiotic for treatment of many high morbidity- and mortality-rated hospital infections, and it is expected to be marketed in the forthcoming years. Therefore, high-yield production of ramoplanin A2 gains importance. In this study, meat-bone meal, poultry meal, and fish meal were used instead of soybean meal for ramoplanin A2 production by Actinoplanes sp. ATCC 33076. All animal origin nitrogen sources stimulated specific productivity. Ramoplanin A2 levels were determined as 406.805 mg L(-1) in fish meal medium and 374.218 mg L(-1) in poultry meal medium. These levels were 4.25- and 4.09-fold of basal medium, respectively. However, the total yield of poultry meal was higher than that of fish meal, which is also low-priced. In addition, the variations in pH levels, protein levels, reducing sugar levels, extracellular protease, amylase and lipase activities, and intracellular free amino acid levels were monitored during the incubation period. The correlations between ramoplanin production and these variables with respect to the incubation period were determined. The intracellular levels of L-Phe, D-Orn, and L-Leu were found critical for ramoplanin A2 production. The strategy of using animal origin nitrogen sources can be applied for large-scale ramoplanin A2 production.

  4. Bacterial Protein-Tyrosine Kinases

    DEFF Research Database (Denmark)

    Shi, Lei; Kobir, Ahasanul; Jers, Carsten

    2010-01-01

    phosphorylation. Protein-tyrosine phosphorylation in bacteria is particular with respect to very low occupancy of phosphorylation sites in vivo; this has represented a major challenge for detection techniques. Only the recent breakthroughs in gel-free high resolution mass spectrometry allowed the systematic...... and highlighted their importance in bacterial physiology. Having no orthologues in Eukarya, BY-kinases are receiving a growing attention from the biomedical field, since they represent a particularly promising target for anti-bacterial drug design....

  5. Functional properties of proteins isolated from industrially produced sunflower meal

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    Petia Ivanova

    2014-10-01

    Full Text Available Protein isolate 1 (PI1 and protein isolate 2 (PI2 were prepared from industrially produced sunflower meal by using isoelectric and ethanol precipitation respectively. The water absorption capacity of PI1 was 6 times higher than that of PI2 and was significantly reduced by the presence of 0.03 M and 0.25 M NaCl. Oil absorption capacity of both protein isolates was not influenced by NaCl supplementation. Foam capacity of PI1 and PI2 was pH-dependent. While the foam capacity of both isolates was improved by either 0.03 M or 0.25 M NaCl, the foam stability was negatively influenced by the addition of NaCl at all pH values with except for pH 4. Emulsifying activity of PI1 and PI2 was lowest at pH 4. The emulsions exhibited relatively high stability (> 90% under all studied conditions. Knowledge of the influence of pH and boundary concentrations of NaCl on the functionality of sunflower meal protein isolates could be beneficial for their future potential application in food industry.

  6. Protein and mineral characterisation of rendered meat and bone meal.

    Science.gov (United States)

    Buckley, M; Penkman, K E H; Wess, T J; Reaney, S; Collins, M J

    2012-10-01

    We report the characterisation of meat and bone meal (MBM) standards (Set B-EFPRA) derived from cattle, sheep, pig and chicken, each rendered at four different temperatures (133, 137, 141 and 145 °C). The standards, prepared for an EU programme STRATFEED (to develop new methodologies for the detection and quantification of illegal addition of mammalian tissues in feeding stuffs), have been widely circulated and used to assess a range of methods for identification of the species composition of MBM. The overall state of mineral alteration and protein preservation as a function of temperature was monitored using small angle X-ray diffraction (SAXS), amino acid composition and racemization analyses. Progressive increases in protein damage and mineral alteration in chicken and cattle standards was observed. In the case of sheep and pig, there was greater damage to the proteins and alteration of the minerals at the lowest treatment temperature (133 °C), suggesting that the thermal treatments must have been compromised in some way. This problem has probably impacted upon the numerous studies which tested methods against these heat treatments. We use protein mass spectrometric methods to explore if thermostable proteins could be used to identify rendered MBM. In more thermally altered samples, so-called 'thermostable' proteins such as osteocalcin which has been proposed as a ideal target to speciate MBM were no longer detectable, but the structural protein type I collagen could be used to differentiate all four species, even in the most thermally altered samples.

  7. Protein and amino acid quality of meat and bone meal.

    Science.gov (United States)

    Parsons, C M; Castanon, F; Han, Y

    1997-02-01

    The in vivo protein quality of 14 meat and bone meals (MBM) was evaluated in three chick growth assays and a 48-h excreta collection assay using conventional and cecectomized roosters. In addition, in vitro evaluation of protein quality was assessed using pepsin N digestibility (0.2, 0.002, or 0.0002% pepsin), KOH protein solubility, and multi-enzyme pH change. Crude protein, lysine, and SAA in the MBM varied from 48 to 56, 2.32 to 3.01, and 1.0 to 2.13%, respectively. Protein efficiency ratio (weight gain:protein intake) estimated from feeding chicks diets containing 9% protein from a MBM ranged from 0.61 to 2.89 and averaged 1.78. Lysine bioavailability determined by slope-ratio chick assay ranged from 43 to 89%. True amino acid digestibility and TMEn values determined in cecectomized roosters were generally lower (P < 0.05) than those determined in conventional roosters. True digestibility of amino acids (percentage) also varied among MBM, with the mean (and range) for lysine, methionine, and cystine in cecectomized birds being 81 (73 to 88), 85 (77 to 91), and 58% (37 to 72%), respectively. Pepsin N digestibility values determined using 0.002 or 0.0002% pepsin were positively correlated (P < 0.05) with lysine digestibility. Pepsin N digestibility determined using 0.2% pepsin, KOH protein solubility, and multi-enzyme pH change were not significantly correlated with in vivo protein quality. Ash content was negatively correlated (-0.80, P < 0.05) with protein efficiency ratio. These results indicated that there is substantial variation in protein quality among commercial MBM and that pepsin N digestibility and ash content are correlated with some in vivo protein quality measurements.

  8. Meals based on vegetable protein sources (beans and peas are more satiating than meals based on animal protein sources (veal and pork – a randomized cross-over meal test study

    Directory of Open Access Journals (Sweden)

    Marlene D. Kristensen

    2016-10-01

    Full Text Available Background: Recent nutrition recommendations advocate a reduction in protein from animal sources (pork, beef because of environmental concerns. Instead, protein from vegetable sources (beans, peas should be increased. However, little is known about the effect of these vegetable protein sources on appetite regulation. Objective: To examine whether meals based on vegetable protein sources (beans/peas are comparable to meals based on animal protein sources (veal/pork regarding meal-induced appetite sensations. Design: In total, 43 healthy, normal-weight, young men completed this randomized, double-blind, placebo-controlled, three-way, cross-over meal test. The meals (all 3.5 MJ, 28 energy-% (E% fat were either high protein based on veal and pork meat, HP-Meat (19 E% protein, 53 E% carbohydrate, 6 g fiber/100 g; high protein based on legumes (beans and peas, HP-Legume (19 E% protein, 53 E% carbohydrate, 25 g fiber/100 g; or low-protein based on legumes, LP-Legume (9 E% protein, 62 E% carbohydrate, 10 g fiber/100 g. Subjective appetite sensations were recorded at baseline and every half hour using visual analog scales until the ad libitum meal 3 h after the test meal. Repeated measurements analyses and summary analyses were performed using ANCOVA (SAS. Results: HP-Legume induced lower composite appetite score, hunger, prospective food consumption, and higher fullness compared to HP-Meat and LP-Legume (p<0.05. Furthermore, satiety was higher after HP-Legume than HP-Meat (p<0.05. When adjusting for palatability, HP-Legume still resulted in lower composite appetite scores, hunger, prospective consumption, and higher fullness compared to HP-Meat (p<0.05. Furthermore, HP-Legume induced higher fullness than LP-Legume (p<0.05. A 12% and 13% lower energy intake, respectively, was seen after HP-Legume compared to HP-Meat or LP-Legume (p<0.01. Conclusion: Vegetable-based meals (beans/peas influenced appetite sensations favorably compared to animal-based meals

  9. Full replacement of menhaden fish meal protein by low-gossypol cottonseed flour protein in the diet of juvenile black sea bass Centropristis striata

    Science.gov (United States)

    Eight iso-nitrogeneous (46% crude protein) and iso-lipidic (14% crude lipid) diets were formulated and prepared to replace menhaden fish meal (FM) protein (59.5% CP) by low-gossypol glandless meal (GCSM) protein (50.4% CP), solvent-extracted cottonseed meal (SCSM) protein (53.8% protein) and high go...

  10. Value Added Processing of Aflatoxin Contaminated Peanut Meal: Aflatoxin Sequestration During Protein Extraction

    Science.gov (United States)

    The efficacy of a bentonite clay, Astra-Ben 20A (AB20A), to sequester aflatoxin from contaminated (~110 ppb) peanut meal during protein extraction was studied. Aqueous peanut meal dispersions (10% w/w) were prepared varying pH, temperature, enzymatic hydrolysis conditions, and concentrations of AB2...

  11. In vivo bacterial morphogenetic protein interactions

    NARCIS (Netherlands)

    van der Ploeg, R.; den Blaauwen, T.; Meghea, A.

    2012-01-01

    This chapter will discuss none-invasive techniques that are widely used to study protein-protein interactions. As an example, their application in exploring interactions between proteins involved in bacterial cell division will be evaluated. First, bacterial morphology and cell division of the rod-s

  12. In vivo bacterial morphogenetic protein interactions

    OpenAIRE

    van der Ploeg, R.; den Blaauwen, T.; Meghea, A.

    2012-01-01

    This chapter will discuss none-invasive techniques that are widely used to study protein-protein interactions. As an example, their application in exploring interactions between proteins involved in bacterial cell division will be evaluated. First, bacterial morphology and cell division of the rod-shaped bacterium Escherichia coli will be introduced. Next, three bacterial two-hybrid methods and three Förster resonance energy transfer detection methods that are frequently applied to detect int...

  13. Defining meal requirements for protein to optimize metabolic roles of amino acids.

    Science.gov (United States)

    Layman, Donald K; Anthony, Tracy G; Rasmussen, Blake B; Adams, Sean H; Lynch, Christopher J; Brinkworth, Grant D; Davis, Teresa A

    2015-04-29

    Dietary protein provides essential amino acids (EAAs) for the synthesis of new proteins plus an array of other metabolic functions; many of these functions are sensitive to postprandial plasma and intracellular amino acid concentrations. Recent research has focused on amino acids as metabolic signals that influence the rate of protein synthesis, inflammation responses, mitochondrial activity, and satiety, exerting their influence through signaling systems including mammalian/mechanistic target of rapamycin complex 1 (mTORC1), general control nonrepressed 2 (GCN2), glucagon-like peptide 1 (GLP-1), peptide YY (PYY), serotonin, and insulin. These signals represent meal-based responses to dietary protein. The best characterized of these signals is the leucine-induced activation of mTORC1, which leads to the stimulation of skeletal muscle protein synthesis after ingestion of a meal that contains protein. The response of this metabolic pathway to dietary protein (i.e., meal threshold) declines with advancing age or reduced physical activity. Current dietary recommendations for protein are focused on total daily intake of 0.8 g/kg body weight, but new research suggests daily needs for older adults of ≥1.0 g/kg and identifies anabolic and metabolic benefits to consuming at least 20-30 g protein at a given meal. Resistance exercise appears to increase the efficiency of EAA use for muscle anabolism and to lower the meal threshold for stimulation of protein synthesis. Applying this information to a typical 3-meal-a-day dietary plan results in protein intakes that are well within the guidelines of the Dietary Reference Intakes for acceptable macronutrient intakes. The meal threshold concept for dietary protein emphasizes a need for redistribution of dietary protein for optimum metabolic health.

  14. Rho-modifying bacterial protein toxins.

    Science.gov (United States)

    Aktories, Klaus

    2015-12-01

    Rho proteins are targets of numerous bacterial protein toxins, which manipulate the GTP-binding proteins by covalent modifications, including ADP ribosylation, glycosylation, adenylylation, proteolytic cleavage and deamidation. Bacterial toxins are important virulence factors but are also potent and efficient pharmacological tools to study the physiological functions of their eukaryotic targets. Recent studies indicate that amazing variations exist in the molecular mechanisms by which toxins attack Rho proteins, which are discussed here.

  15. The nutrient composition of European ready meals: protein, fat, total carbohydrates and energy.

    Science.gov (United States)

    Kanzler, Sonja; Manschein, Martin; Lammer, Guido; Wagner, Karl-Heinz

    2015-04-01

    Despite the increasing social importance of ready meals, only few studies have been conducted on their nutrient composition. Therefore, 32 chilled, frozen and heat-treated ready meals (only main dishes) from the continental European market were analysed for protein, fat, total carbohydrate and energy. Half of the meals were nutritionally imbalanced by providing elevated fat (>30% of energy) and low carbohydrate levels (<50% of energy). Protein was generally above recommendations and ranged from 8.0 to 47.2g per serving. The inter-package variation was high, reaching 19.04 ± 2.90 g/package for fat. After proposing understandable guidelines to improve nutritional quality for the food industry, seven "nutritionally optimised" ready meals were created at the European level and analysed, however success was limited. If product labelling is to be useful for consumers, our results also indicate a need for better quality control to reduce the differences between content and labelling.

  16. Effect of meal size reduction and protein enrichment on intake and satiety in vital community-dwelling older adults.

    Science.gov (United States)

    Ziylan, Canan; Kremer, Stefanie; Eerens, Jessie; Haveman-Nies, Annemien; de Groot, Lisette C P G M

    2016-10-01

    Undernutrition risk among community-dwelling older adults is partly caused by inadequate protein intake. Enriching readymade meals with protein could be beneficial in increasing protein intake. Moreover, reduced-size meals could suit older adults with diminished appetite. In this single-blind randomized crossover study with 120 participants (age: 70.5 ± 4.5 y, BMI: 27.2 ± 4.4 kg/m(2)), 60 participants consumed four beef meals and another 60 consumed four chicken meals on four different days, once per week. These meals were produced according to a 2 × 2 factorial design: the protein content was either ∼25 g (lower) or ∼30 g (enriched), and the portion size was either 450 g (normal) or of 400 g (reduced). Palatability evaluation, meal intake, and subsequent satiety ratings after 120 min were measured. No significant differences in palatability among meals were found. While absolute intake (g) of the normal-size meals was significantly higher than that of the reduced-size meals, the relative intake (%) of the served meals did not differ between the four meals. Both protein and energy intakes were significantly higher for the enriched meals, regardless of portion size. Protein intakes were 5.4 g and 5.1 g higher in the normal-size and reduced-size enriched beef meals, respectively, and 6.1 g and 7.1 g higher in the enriched chicken meals, respectively. The normal-size enriched beef meal and reduced-size enriched chicken meal led to slightly but significantly higher ratings of satiety than the non-enriched meals. Due to these mixed satiety findings, separate effects of meal-size reduction and protein enrichment could not be distinguished in this study. The intake findings show that palatable protein-enriched meals support higher protein and energy intakes in vital community-dwelling older adults during a single meal.

  17. The effect of within-meal protein content and taste on subsequent food choice and satiety

    NARCIS (Netherlands)

    Griffioen-Roose, S.; Mars, M.; Finlayson, G.; Blundell, J.E.; Graaf, de C.

    2011-01-01

    It is posed that protein intake is tightly regulated by the human body. The role of sensory qualities in the satiating effects of protein, however, requires further clarification. Our objective was to determine the effect of within-meal protein content and taste on subsequent food choice and satiety

  18. Meal composition and plasma amino acid ratios: Effect of various proteins or carbohydrates, and of various protein concentrations

    Science.gov (United States)

    Yokogoshi, Hidehiko; Wurtman, Richard J.

    1986-01-01

    The effects of meals containing various proteins and carbohydrates, and of those containing various proportions of protein (0 percent to 20 percent of a meal, by weight) or of carbohydrate (0 percent to 75 percent), on plasma levels of certain large neutral amino acids (LNAA) in rats previously fasted for 19 hours were examined. Also the plasma tryptophan ratios (the ratio of the plasma trytophan concentration to the summed concentrations of the other large neutral amino acids) and other plasma amino acid ratios were calculated. (The plasma tryptophan ratio has been shown to determine brain tryptophan levels and, thereby, to affect the synthesis and release of the neurotransmitter serotonin). A meal containing 70 percent to 75 percent of an insulin-secreting carbohydrate (dextrose or dextrin) increased plasma insulin levels and the tryptophan ratio; those containing 0 percent or 25 percent carbohydrate failed to do so. Addition of as little as 5 percent casein to a 70 percent carbohydrate meal fully blocked the increase in the plasma tryptophan ratio without affecting the secretion of insulin - probably by contributing much larger quantities of the other LNAA than of tryptophan to the blood. Dietary proteins differed in their ability to suppress the carbohydrate-induced rise in the plasma tryptophan ratio. Addition of 10 percent casein, peanut meal, or gelatin fully blocked this increase, but lactalbumin failed to do so, and egg white did so only partially. (Consumption of the 10 percent gelatin meal also produced a major reduction in the plasma tyrosine ratio, and may thereby have affected brain tyrosine levels and catecholamine synthesis.) These observations suggest that serotonin-releasing neurons in brains of fasted rats are capable of distinguishing (by their metabolic effects) between meals poor in protein but rich in carbohydrates that elicit insulin secretion, and all other meals. The changes in brain serotonin caused by carbohydrate-rich, protein

  19. Bacterial binding to extracellular proteins - in vitro adhesion

    DEFF Research Database (Denmark)

    Schou, C.; Fiehn, N.-E.

    1999-01-01

    Viridans streptococci, bacterial adherence, extracellular matrix proteins, surface receptors, endocarditis......Viridans streptococci, bacterial adherence, extracellular matrix proteins, surface receptors, endocarditis...

  20. Studies on protein characteristics and toxic constituents of Simarouba glauca oilseed meal.

    Science.gov (United States)

    Govindaraju, K; Darukeshwara, J; Srivastava, Alok K

    2009-06-01

    In order to exploit the protein rich (47.7 g/100g) simarouba meal in food/feed, studies were conducted on its chemical composition with emphasis on protein characteristics and toxic constituents. Simarouba meal contained high calcium (143 mg/100g) and sodium (79 mg/100g). Saponins with triterpenoid aglycone (3.7 g/100g), alkaloids (1.01 g/100g), phenolics (0.95 g/100g) and phytic acid (0.73 g/100g) were the major toxic constituents identified in simarouba meal. TLC and HPLC results indicated that among different fractions of simarouba saponins, one dominant fraction accounted for about 28%. Proteins of simarouba recorded high in vitro digestibility (88%). SDS-PAGE revealed four major protein bands in molecular weight ranges of 20-24, 36-45 and 55-66 kDa. Apart from, glutamic acid (23.43 g/100g protein) and arginine (10.75 g/100g protein), simarouba protein contained high essential amino acids like leucine (7.76 g/100g protein), lysine (5.62 g/100g protein) and valine (6.12 g/100g protein). Among nutritional indices, simarouba meal recorded a good EAA Index (75.02), C-PER (1.90) and PDCAAS (1.0-Adult group).

  1. Sensory properties of meal replacement bars and beverages made from whey and soy proteins.

    Science.gov (United States)

    Childs, J L; Yates, M D; Drake, M A

    2007-08-01

    Whey and soy proteins have a variety of applications. Previous work has documented flavors of rehydrated whey and soy proteins. It is necessary to understand what flavors whey and soy proteins contribute to product applications to optimize protein performance in desired applications. This research was conducted to characterize sensory properties of meal replacement products containing whey and soy proteins. Flavor and texture lexicons were developed for meal replacement bars and beverages. Commercial peanut butter-flavored meal replacement bars and vanilla meal replacement shakes were evaluated by an experienced, trained descriptive panel (n= 9). Prototypes of bars and beverages were developed with 3 levels of whey and soy protein and subsequently evaluated. Consumer acceptance testing (n= 85) was conducted on the prototype bars and beverages. Protein type as well as product-specific formulation contributed differences in flavor and texture of commercial bars and beverages (P whey protein were characterized by sweet aromatic and vanillin flavor notes while the texture was characterized by adhesiveness and cohesiveness. Prototype bars made with soy protein were characterized by nutty flavor while the texture was characterized by tooth-pack and denseness. Whey protein contributed to sweet aromatic and vanillin flavors in prototype beverages while soy protein contributed cereal/grainy flavors. Consumer acceptance scores were higher for prototype bars and beverages containing whey protein or a mixture of whey/soy protein than for products made with soy protein alone (P < 0.05). These results will aid researchers and product developers in optimizing sensory quality in meal replacement products.

  2. Umami taste amino acids produced by hydrolyzing extracted protein from tomato seed meal

    Science.gov (United States)

    Enzymatic hydrolysis was performed for extracting protein to prepare umami taste amino acids from defatted tomato seed meal (DTSM) which is a by-product of tomato processing. Papain was used as an enzyme for the hydrolysis of DTSM. The particle size distribution of DTSM, protein concentration and fr...

  3. Recombinant protein production in bacterial hosts.

    Science.gov (United States)

    Overton, Tim W

    2014-05-01

    The production of recombinant proteins is crucial for both the development of new protein drugs and the structural determination of drug targets. As such, recombinant protein production has a major role in drug development. Bacterial hosts are commonly used for the production of recombinant proteins, accounting for approximately 30% of current biopharmaceuticals on the market. In this review, I introduce fundamental concepts in recombinant protein production in bacteria, from drug development to production scales. Recombinant protein production processes can often fail, but how can this failure be minimised to rapidly deliver maximum yields of high-quality protein and so accelerate drug discovery?

  4. Differential effects of protein quality on postprandial lipemia in response to a fat-rich meal in type 2 diabetes: comparison of whey, casein, gluten, and cod protein

    DEFF Research Database (Denmark)

    Mortensen, Lene S; Hartvigsen, Merete L; Brader, Lea J

    2009-01-01

    : The objective was to compare the effects of the proteins casein, whey, cod, and gluten on postprandial lipid and incretin responses to a high-fat meal in persons with type 2 diabetes. DESIGN: A crossover study was conducted in 12 patients with type 2 diabetes. Blood samples were collected over 8 h after...... ingestion of a test meal containing 100 g butter and 45 g carbohydrate in combination with 45 g casein (Cas-meal), whey (Whe-meal), cod (Cod-meal), or gluten (Glu-meal). We measured plasma concentrations of triglycerides, retinyl palmitate (RP), free fatty acids, insulin, glucose, glucagon, glucagon......, glucagon-like peptide 1, and glucose-dependent insulinotropic peptide responses. CONCLUSION: The data suggest that as a supplement to a fat-rich meal in patients with type 2 diabetes, whey protein seems to outperform other proteins in terms of postprandial lipemia improvement, possibly because...

  5. Addition of Astra-Ben 20 to Sequester Aflatoxin During Protein Extraction of Contaminated Peanut Meal

    Science.gov (United States)

    Peanut meal is an excellent source of high quality protein; however, the relatively high aflatoxin concentrations typically associated with this commodity currently limit applications within the feed market, in addition to being prohibitive for any future food ingredient markets. Accordingly, the e...

  6. Determination of processed animal proteins, including meat and bone meal, in animal feed

    NARCIS (Netherlands)

    Gizzi, G.; Holst, von C.; Baeten, V.; Berben, G.; Raamsdonk, van L.W.D.

    2004-01-01

    The presence of processed animal proteins (PAP), including meat and bone meal (MBM) from various species, in animal feed was investigated. It was demonstrated that microscopy is the most reliable method for enforcing the current total MBM ban in the European Uion (EU). It was shown that near infrare

  7. C-reactive protein and bacterial meningitis

    DEFF Research Database (Denmark)

    Gerdes, Lars Ulrik; Jørgensen, P E; Nexø, E;

    1998-01-01

    The aim of the study was to review published articles on the diagnostic accuracy of C-reactive protein (CRP) tests with cerebrospinal fluid and serum in diagnosing bacterial meningitis. The literature from 1980 and onwards was searched using the electronic databases of MEDLINE, and we used summary...

  8. Substitution of Soybean Meal and Cornmeal to Moisture, pH, Bacterial Colony Forming and Shelf Life of Rejected Duck Meatballs

    Directory of Open Access Journals (Sweden)

    Novia Deni

    2013-01-01

    Full Text Available This study aimed to determine the effect of substitution of soybean meal with cornmeal to moisture, pH, bacterial colony forming and the shelf life of rejected duck meatballs. This research material using duck meat Coast (Indian Runner salvage as much as 4000 grams were obtained from the Livestock Anduring Padang and soybean meal with Mungbean trademarks and cornmeal with cornstarch trademarks respectively of 600 grams were obtained at Raya Padang market. The research method used was experimental method with the random design, which consists of 5 treatments and 4 groups as replication. The treatment given in this study is the substitution of soybean meal and maize by A (100%: 0%, B (75%: 25%, C (50%: 50%, D (25%: 75% and E (0%: 100%. Variables measured were moisture, pH, bacterial colony forming and the shelf life of rejected duck meatballs. The results of this study indicate that substitution of soybean meal and cornmeal significant effect on moisture, pH, bacterial colony forming and shelf life. Substitution of soybean meal and cornmeal by 100%: 0% is the best to produce the rejected duck meatballs with 69.20% moisture, pH 6.44, bacterial colony forming 7.85 x 105 CFU / g, and the shelf life of 22.12 hours.

  9. Evaluation of standardized ileal digestible valine:lysine, total lysine:crude protein, and replacing fish meal, meat and bone meal, and poultry byproduct meal with crystalline amino acids on growth performance of nursery pigs from seven to twelve kilograms.

    Science.gov (United States)

    Nemechek, J E; Tokach, M D; Dritz, S S; Goodband, R D; DeRouchey, J M

    2014-04-01

    Five experiments were conducted to evaluate replacing fish meal, meat and bone meal, and poultry byproduct meal with crystalline AA for 7- to 12-kg pigs. In all experiments, pigs (PIC TR4 × 1050) were fed a common diet for 3 d postweaning, treatment diets for 14 d (d 0 to 14), and, again, a common diet for 14 d (d 14 to 28). Treatment diets were corn-soybean meal based and formulated to contain 1.30% standardized ileal digestible (SID) Lys. Experiment 1 evaluated replacing dietary fish meal with crystalline AA. For the 6 treatments, crystalline Lys, Met, Thr, Trp, Ile, Val, Gln, and Gly all increased to maintain minimum AA ratios as fish meal decreased (4.50, 3.60, 2.70, 1.80, and 0.90 to 0.00%). There was no difference in ADG, ADFI, or G:F among treatments, validating a low-CP, AA-fortified diet for subsequent experiments. Experiment 2 evaluated deleting crystalline AA from a low-CP, AA-fortified diet with 6 treatments: 1) a positive control similar to the diet validated in Exp. 1, 2) positive control with l-Ile deleted, 3) positive control with l-Trp deleted, 4) positive control with l-Val deleted, 5) positive control with l-Gln and l-Gly deleted, and 6) positive control with l-Ile, l-Trp, l-Val, l-Gln, and l-Gly deleted (NC). Pigs fed the positive control or Ile deleted diet had improved (P meal was adjusted as a source of dispensable N to achieve the target Lys:CP. There were no differences in growth performance among pigs fed different Lys:CP diets. Experiment 4 evaluated increasing SID Val:Lys with Val at 57.4, 59.9, 62.3, 64.7, 67.2, and 69.6% of Lys. Average daily gain and ADFI increased (quadratic, P meal, meat and bone meal, or poultry byproduct meal). Low- and high-crystalline AA diets contained 4.5 or 1% fish meal, 6 or 1.2% meat and bone meal, and 6 or 1% poultry byproduct meal, respectively. No AA × protein source interactions were observed. From d 0 to 14, no differences in growth performance among protein sources was found, whereas increasing

  10. Genetic impact on protein content and hullability of sunflower seeds, and on the quality of sunflower meal

    Directory of Open Access Journals (Sweden)

    Dauguet Sylvie

    2016-03-01

    Full Text Available Sunflower seed quality, in particular the characteristics of hullability and protein content, has a significant impact on the protein content of the resulting meal. Seeds dehulled before crushing produce a meal with a protein content of approximately 36%; without dehulling, the protein content is typically in the range of 27–29%. This study seeks to assess the effect of sunflower variety on hullability and protein content. Genetic effects were studied by means of seed samples obtained from a network of variety evaluation trials undertaken across the production area in France for sunflowers. For both characteristics, significant differences between cultivars were observed; as a consequence, the potential protein content of their dehulled meals also ranged widely (34–44%. Genetic selection, which provides substantial improvements in both oil content and fatty acid composition, should therefore be expected to enhance the quality of sunflower meal.

  11. Gut Commensal E. coli Proteins Activate Host Satiety Pathways following Nutrient-Induced Bacterial Growth.

    Science.gov (United States)

    Breton, Jonathan; Tennoune, Naouel; Lucas, Nicolas; Francois, Marie; Legrand, Romain; Jacquemot, Justine; Goichon, Alexis; Guérin, Charlène; Peltier, Johann; Pestel-Caron, Martine; Chan, Philippe; Vaudry, David; do Rego, Jean-Claude; Liénard, Fabienne; Pénicaud, Luc; Fioramonti, Xavier; Ebenezer, Ivor S; Hökfelt, Tomas; Déchelotte, Pierre; Fetissov, Sergueï O

    2016-02-09

    The composition of gut microbiota has been associated with host metabolic phenotypes, but it is not known if gut bacteria may influence host appetite. Here we show that regular nutrient provision stabilizes exponential growth of E. coli, with the stationary phase occurring 20 min after nutrient supply accompanied by bacterial proteome changes, suggesting involvement of bacterial proteins in host satiety. Indeed, intestinal infusions of E. coli stationary phase proteins increased plasma PYY and their intraperitoneal injections suppressed acutely food intake and activated c-Fos in hypothalamic POMC neurons, while their repeated administrations reduced meal size. ClpB, a bacterial protein mimetic of α-MSH, was upregulated in the E. coli stationary phase, was detected in plasma proportional to ClpB DNA in feces, and stimulated firing rate of hypothalamic POMC neurons. Thus, these data show that bacterial proteins produced after nutrient-induced E. coli growth may signal meal termination. Furthermore, continuous exposure to E. coli proteins may influence long-term meal pattern.

  12. Zinc absorption from composite meals. I. The significance of whest extraction rate, zinc, calcium, and protein content in meals based on bread.

    Science.gov (United States)

    Sandström, B; Arvidsson, B; Cederblad, A; Björn-Rasmussen, E

    1980-04-01

    The absorption of zinc in man from composite meals based on bread was measured with a radionuclide technique using 65Zn and whole-body counting. Bread was made up from wheat flour of 100 and 72% extraction rate. A lower absolute amount of zinc was absorbed from the white bread compared to the absorption from the same amount of wholemeal bread. When the two types of bread were enriched with zinc chloride the absorption was higher from the white bread than from the wholemeal bread. Addition of calcium in the form of milk products improved the absorption of zinc from a meal with wholemeal bread. A significant positive correlation was found between zinc absorption and the protein content in meals containing milk, cheese, beef, and egg in various combinations with the wholemeal bread.

  13. The effect of within-meal protein content and taste on subsequent food choice and satiety.

    Science.gov (United States)

    Griffioen-Roose, Sanne; Mars, Monica; Finlayson, Graham; Blundell, John E; de Graaf, Cees

    2011-09-01

    It is posed that protein intake is tightly regulated by the human body. The role of sensory qualities in the satiating effects of protein, however, requires further clarification. Our objective was to determine the effect of within-meal protein content and taste on subsequent food choice and satiety. We used a cross-over design whereby sixty healthy, unrestrained subjects (twenty-three males and thirty-seven females) with a mean age of 20·8 (SD 2·1) years and a mean BMI of 21·5 (SD 1·6) kg/m2 were offered one of four isoenergetic preloads (rice meal) for lunch: two low in protein (about 7 % energy derived from protein) and two high in protein (about 25 % energy from protein). Both had a sweet and savoury version. At 30 min after preload consumption, subjects were offered an ad libitum buffet, consisting of food products differing in protein content (low/high) and taste (sweet/savoury). In addition, the computerised Leeds Food Preference Questionnaire (LFPQ) was run to assess several components of food reward. The results showed no effect of protein content of the preloads on subsequent food choice. There was an effect of taste; after eating the savoury preloads, choice and intake of sweet products were higher than of savoury products. No such preference was seen after the sweet preloads. No differences in satiety were observed. To conclude, within one eating episode, within-meal protein content in these quantities seems not to have an effect on subsequent food choice. This appears to be mostly determined by taste, whereby savoury taste exerts the strongest modulating effect. The results of the LFPQ provided insight into underlying processes.

  14. Effects of feeding high protein or conventional canola meal on dry cured and conventionally cured bacon.

    Science.gov (United States)

    Little, K L; Bohrer, B M; Stein, H H; Boler, D D

    2015-05-01

    Objectives were to compare belly, bacon processing, bacon slice, and sensory characteristics from pigs fed high protein canola meal (CM-HP) or conventional canola meal (CM-CV). Soybean meal was replaced with 0 (control), 33, 66, or 100% of both types of canola meal. Left side bellies from 70 carcasses were randomly assigned to conventional or dry cure treatment and matching right side bellies were assigned the opposite treatment. Secondary objectives were to test the existence of bilateral symmetry on fresh belly characteristics and fatty acid profiles of right and left side bellies originating from the same carcass. Bellies from pigs fed CM-HP were slightly lighter and thinner than bellies from pigs fed CM-CV, yet bacon processing, bacon slice, and sensory characteristics were unaffected by dietary treatment and did not differ from the control. Furthermore, testing the existence of bilateral symmetry on fresh belly characteristics revealed that bellies originating from the right side of the carcasses were slightly (P≤0.05) wider, thicker, heavier and firmer than bellies from the left side of the carcass.

  15. Enzyme-Enhanced Extraction of Phenolic Compounds and Proteins from Flaxseed Meal

    OpenAIRE

    Bernardo Dias Ribeiro; Daniel Weingart Barreto; Maria Alice Zarur Coelho

    2013-01-01

    Flaxseed (Linum usitatissimum) meal, the main byproduct of the flaxseed oil extraction process, is composed mainly of proteins, mucilage, and phenolic compounds. The extraction methods of phenolics either commonly employed the use of mixed solvents (dioxane/ethanol, water/acetone, water/methanol, and water/ethanol) or are done with the aid of alkaline, acid, or enzymatic hydrolysis. This work aimed at the study of optimal conditions for a clean process, using renewable solvents and enzymes, f...

  16. Soybean Meal Protein Assay -Cross lab tests and Kjeldhal vs Leco

    Institute of Scientific and Technical Information of China (English)

    Yiqiang (Bill) Xiong; Zu Liya; Chang Biying; Xing Jianjun

    2002-01-01

    @@ Introduction Accuracy/precision of crude protein assay (CP) iscritical for the trade of soybean meal (SBM) and feedformulation. Past experience indicated that the CPassay variation in China could be very large and farbeyond AFCO Analytical Variation (AV%, previouslyPermitted Analytical Variation or PAV%). On CP testprocedures recently there has been a saying that theLeco combustion method was more accurate than theclassical Kjeldahl procedure.

  17. Oxidative stability and sensory quality of meat from broiler chickens fed a bacterial meal produced on natural gas.

    Science.gov (United States)

    Øverland, M; Borge, G I; Vogt, G; Schøyen, H F; Skrede, A

    2011-01-01

    Bacterial meal (BPM) produced from bacteria grown on natural gas is a feed source containing approximately 70% CP and 10% lipids with predominantly C16:0 and C16:1 fatty acids. The effect of increasing dietary levels (0, 40, 80, or 120 g/kg) of BPM on fatty acid composition, the profile of volatiles by dynamic headspace gas chromatography-mass spectrometry, and sensory quality of frozen-stored broiler chicken thigh meat was examined. Increasing levels of BPM increased (linear, P Dynamic headspace gas chromatography-mass spectrometry was a more sensitive method in detecting early lipid oxidation compared with TBA reactive substances and sensory quality analyses in broiler thigh meat.

  18. Replacement of fish meal by protein soybean concentrate in practical diets for Pacific white shrimp

    Directory of Open Access Journals (Sweden)

    Mariana Soares

    2015-10-01

    Full Text Available ABSTRACTThe objective of this work was to evaluate the performance of Litopenaeus vannameifed different levels (0, 25, 50, 75, and 100% of soybean protein concentrate (63.07% crude protein, CP to replace fish meal-by product (61.24% CP. The study was conducted in clear water in fifteen 800 L tanks equipped with aeration systems, constant heating (29 ºC, and daily water exchange (30%. Each tank was stocked with 37.5 shrimp/m3 (3.03±0.14 g. Feed was supplied four times a day, at 6% of the initial biomass, adjusted daily. After 42 days, the weight gain of shrimp fed diets with 0 and 25% protein replacement was higher than that observed in shrimp fed 100% replacement, and there were no differences among those fed the other diets. Feed efficiency and survival did not differ among shrimp fed different protein replacements. There was a negative linear trend for growth parameters and feed intake as protein replacement with soybean protein concentrate increased. Fish meal by-product can be replaced by up to 75% of soybean protein concentrate, with no harm to the growth of Pacific white shrimp.

  19. Fluorescent sensors based on bacterial fusion proteins

    Science.gov (United States)

    Prats Mateu, Batirtze; Kainz, Birgit; Pum, Dietmar; Sleytr, Uwe B.; Toca-Herrera, José L.

    2014-06-01

    Fluorescence proteins are widely used as markers for biomedical and technological purposes. Therefore, the aim of this project was to create a fluorescent sensor, based in the green and cyan fluorescent protein, using bacterial S-layers proteins as scaffold for the fluorescent tag. We report the cloning, expression and purification of three S-layer fluorescent proteins: SgsE-EGFP, SgsE-ECFP and SgsE-13aa-ECFP, this last containing a 13-amino acid rigid linker. The pH dependence of the fluorescence intensity of the S-layer fusion proteins, monitored by fluorescence spectroscopy, showed that the ECFP tag was more stable than EGFP. Furthermore, the fluorescent fusion proteins were reassembled on silica particles modified with cationic and anionic polyelectrolytes. Zeta potential measurements confirmed the particle coatings and indicated their colloidal stability. Flow cytometry and fluorescence microscopy showed that the fluorescence of the fusion proteins was pH dependent and sensitive to the underlying polyelectrolyte coating. This might suggest that the fluorescent tag is not completely exposed to the bulk media as an independent moiety. Finally, it was found out that viscosity enhanced the fluorescence intensity of the three fluorescent S-layer proteins.

  20. Jojoba seed meal proteins associated with proteolytic and protease inhibitory activities.

    Science.gov (United States)

    Shrestha, Madan K; Peri, Irena; Smirnoff, Patricia; Birk, Yehudith; Golan-Goldhirsh, Avi

    2002-09-25

    The jojoba, Simmondsia chinensis, is a characteristic desert plant native to the Sonoran desert. The jojoba meal after oil extraction is rich in protein. The major jojoba proteins were albumins (79%) and globulins (21%), which have similar amino acid compositions and also showed a labile thrombin-inhibitory activity. SDS-PAGE showed two major proteins at 50 kDa and 25 kDa both in the albumins and in the globulins. The 25 kDa protein has trypsin- and chymotrypsin-inhibitory activities. In vitro digestibility of the globulins and albumins resembled that of casein and soybean protein concentrates and was increased after heat treatment. The increased digestibility achieved by boiling may be attributed to inactivation of the protease inhibitors and denaturation of proteins.

  1. THE DISTRIBUTION OF ELECTROPHORETIC FRACTIONS OF PROTEIN ISOLATES FROM SUNFLOWER MEAL

    Directory of Open Access Journals (Sweden)

    Voronova N. S.

    2014-12-01

    Full Text Available The food status of Russians is characterized by deficiency of protein. Perspective sources of food protein are the secondary resources of the oil and fat industry received when processing seeds of sunflower, including sunflower meal. Unfortunately, the features of technological process at the oilextracting press exclude a possibility of receiving food protein-containing products from them without the additional processing increasing biological value and improving technical characteristics of proteins. On the basis of the above information, the researches of a protein complex of sunflower cake, development of ways of regulation of its functional and technological properties and increase of biological value is up-to-date. The article presents the analysis of the influence of enzymatic modification on the distribution of electrophoretic fractions of the modified protein isolates

  2. In vitro crude protein digestibility of Tenebrio molitor and Hermetia illucens insect meals and its correlation with chemical composition traits

    Directory of Open Access Journals (Sweden)

    Stefania Marono

    2015-07-01

    Full Text Available The aims of this study were to evaluate the correlation between in vitro crude protein digestibility coefficients of insect meals from Tenebrio molitor (TI and Hermetia illucens (HI and their chemical composition traits as well as to develop regression equations able to estimate the in vitro crude protein digestibility (CPd from proximate analysis of insect meals. Twelve samples of insect meals (6 from TM larvae, TM 1-6 and 6 from HI larvae, HI 1-6 were obtained from different producers and analysed for chemical composition and in vitro crude protein digestibility by a two-step enzymatic method (digestion with pepsin and trypsin-enriched pancreatin. For both insect meal samples, CPd was negatively correlated to ADF and chitin contents, while just for HI there was a positive correlation (P<0.01 between CP percentage of the samples and CPd. For both insect meals the former variable chosen in the stepwise analysis was the chitin, explaining the 79.45% of CPd variability for Tenebrio molitor samples and the 98.30% for Hermetia illucens. In the second step, the amount of protein linked to ADF was added in the model for T. molitor and CP for H. illucens samples. The coefficients chitin is the main constituent of insect body able to affect the crude protein digestibility of Tenebrio molitor and Hermetia illucens larvae meals estimated by an in vitro enzymatic method.

  3. Bacterial protein toxins : tools to study mammalian molecular cell biology

    NARCIS (Netherlands)

    Wüthrich, I.W.

    2014-01-01

    Bacterial protein toxins are genetically encoded proteinaceous macromolecules that upon exposure causes perturbation of cellular metabolism in a susceptible host. A bacterial toxin can work at a distance from the site of infection, and has direct and quantifiable actions. Bacterial protein toxins ca

  4. Novel receptors for bacterial protein toxins.

    Science.gov (United States)

    Schmidt, Gudula; Papatheodorou, Panagiotis; Aktories, Klaus

    2015-02-01

    While bacterial effectors are often directly introduced into eukaryotic target cells by various types of injection machines, toxins enter the cytosol of host cells from endosomal compartments or after retrograde transport via Golgi from the ER. A first crucial step of toxin-host interaction is receptor binding. Using optimized protocols and new methods novel toxin receptors have been identified, including metalloprotease ADAM 10 for Staphylococcus aureus α-toxin, laminin receptor Lu/BCAM for Escherichia coli cytotoxic necrotizing factor CNF1, lipolysis stimulated lipoprotein receptor (LSR) for Clostridium difficile transferase CDT and low-density lipoprotein receptor-related protein (LRP) 1 for Clostridium perfringens TpeL toxin.

  5. GROWTH OF POULTRY CHICKS FED ON FORMULATED FEED CONTAINING SILK WORM PUPAE MEAL AS PROTEIN SUPPLEMENT AND COMMERCIAL DIET

    Directory of Open Access Journals (Sweden)

    A. DUTTA

    2012-05-01

    Full Text Available Waste silkworm pupae (SWP generate vast resources of nutrients for livestock and poultry. In the present investigation, three days old chicks of RIR strain were allocated to five dietary treatments of silk worm pupae meal. The energy budget was prepared from calculated proximate analysis and growth performance of broiler chicks fed with different percentages of silk worm pupae. The result showed that the silkworm powder meal (SWPM is the cheapest and has potential to replace the costly and contaminated fish meal, as the protein source, used in poultry industry.

  6. Evaluation of various combinations of alternative protein feedstuffs to replace soybean meal in diets for pond-raised channel catfish

    Science.gov (United States)

    A study was conducted in earthen ponds to evaluate the use of combinations of two or three alternative protein sources to replace soybean meal in diets for Channel Catfish Ictalurus punctatus. Six 28% protein diets containing various combinations of alternative protein feedstuffs including cottonse...

  7. Impact of a novel protein meal on the gastrointestinal microbiota and host transcriptome of larval zebrafish Danio rerio

    Directory of Open Access Journals (Sweden)

    Eugene eRurangwa

    2015-04-01

    Full Text Available Larval zebrafish was subjected to a methodological exploration of the gastrointestinal microbiota and transcriptome. Assessed was the impact of two dietary inclusion levels of a novel protein meal (NPM of animal origin (ragworm Nereis virens on the gastrointestinal tract (GIT. Microbial development was assessed over the first 21 days post egg fertilisation (dpf through 16S rRNA gene-based microbial composition profiling by pyrosequencing. Differentially expressed genes in the GIT were demonstrated at 21 dpf by whole transcriptome sequencing (mRNAseq. Larval zebrafish showed rapid temporal changes in microbial colonization but domination occurred by one to three bacterial species generally belonging to Proteobacteria and Firmicutes. The high iron content of NPM may have led to an increased relative abundance of bacteria that were related to potential pathogens and bacteria with an increased iron metabolism. Functional classification of the 328 differentially expressed genes indicated that the GIT of larvae fed at higher NPM level was more active in transmembrane ion transport and protein synthesis. mRNAseq analysis did not reveal a major activation of genes involved in the immune response or indicating differences in iron uptake and homeostasis in zebrafish fed at the high inclusion level of NPM.

  8. The influence of protein containing meals on the pharmacokinetics of levodopa in healthy volunteers.

    OpenAIRE

    Robertson, D. R.; Higginson, I; MACKLIN, B. S.; Renwick, A G; Waller, D G; George, C F

    1991-01-01

    1. The pharmacokinetics of levodopa and paracetamol after single oral doses have been investigated in eight healthy young volunteers in the fasted state and following isocaloric meals containing either 10.5 g or 30.5 g of protein. 2. The initial peak and maximum plasma drug concentrations and the times at which these occurred were not affected by food. 3. The mean area under the plasma concentration-time curve (AUC) for paracetamol following an overnight fast did not differ significantly from...

  9. Protein and amino acid bioavailability of extruded dog food with protein meals of different quality using growing mink (Neovison vison) as a model

    DEFF Research Database (Denmark)

    Tjernsbekk, M. T.; Tauson, Anne-Helene; Matthiesen, Connie Frank

    2016-01-01

    The present study evaluated growing mink (Neovison vison) as a model for dietary protein quality assessment of protein meals used in extruded dog foods. Three foods with similar CP content but of different protein quality were produced using different protein meals. The protein meals varied...... with respect to CP digestibility and AA composition and included lamb meal (LBM), poultry meal (PM), and fish meal (FM) with low, intermediate, and high protein quality, respectively. Nitrogen balance, BW gain, protein efficiency ratio (PER), and apparent total tract digestibility (ATTD) were used as measures.......001) in ATTD of CP and all AA, except for hydroxyproline. Retention of N was 0.66, 1.04, and 1.18 g·kg−0.75·d−1; BW gain was 8.2, 26.8, and 35.3 g/d; PER was 0.38, 1.39, and 1.71; and ATTD of CP was 66.8, 73.8, and 82.1% for the LBM, PM, and FM diets, respectively. In dogs, SID of CP and AA differed (P ≤ 0...

  10. Bacterial proteins pinpoint a single eukaryotic root.

    Science.gov (United States)

    Derelle, Romain; Torruella, Guifré; Klimeš, Vladimír; Brinkmann, Henner; Kim, Eunsoo; Vlček, Čestmír; Lang, B Franz; Eliáš, Marek

    2015-02-17

    The large phylogenetic distance separating eukaryotic genes and their archaeal orthologs has prevented identification of the position of the eukaryotic root in phylogenomic studies. Recently, an innovative approach has been proposed to circumvent this issue: the use as phylogenetic markers of proteins that have been transferred from bacterial donor sources to eukaryotes, after their emergence from Archaea. Using this approach, two recent independent studies have built phylogenomic datasets based on bacterial sequences, leading to different predictions of the eukaryotic root. Taking advantage of additional genome sequences from the jakobid Andalucia godoyi and the two known malawimonad species (Malawimonas jakobiformis and Malawimonas californiana), we reanalyzed these two phylogenomic datasets. We show that both datasets pinpoint the same phylogenetic position of the eukaryotic root that is between "Unikonta" and "Bikonta," with malawimonad and collodictyonid lineages on the Unikonta side of the root. Our results firmly indicate that (i) the supergroup Excavata is not monophyletic and (ii) the last common ancestor of eukaryotes was a biflagellate organism. Based on our results, we propose to rename the two major eukaryotic groups Unikonta and Bikonta as Opimoda and Diphoda, respectively.

  11. Bacterial proteins and peptides in cancer therapy

    Science.gov (United States)

    Chakrabarty, Ananda M; Bernardes, Nuno; Fialho, Arsenio M

    2014-01-01

    Cancer is one of the most deadly diseases worldwide. In the last three decades many efforts have been made focused on understanding how cancer grows and responds to drugs. The dominant drug-development paradigm has been the “one drug, one target.” Based on that, the two main targeted therapies developed to combat cancer include the use of tyrosine kinase inhibitors and monoclonal antibodies. Development of drug resistance and side effects represent the major limiting factors for their use in cancer treatment. Nowadays, a new paradigm for cancer drug discovery is emerging wherein multi-targeted approaches gain ground in cancer therapy. Therefore, to overcome resistance to therapy, it is clear that a new generation of drugs is urgently needed. Here, regarding the concept of multi-targeted therapy, we discuss the challenges of using bacterial proteins and peptides as a new generation of effective anti-cancer drugs. PMID:24875003

  12. In Vitro Rumen Fermentation and Anti Mastitis Bacterial Activity of Diet Containing Betel Leaf Meal (Piper betle L.

    Directory of Open Access Journals (Sweden)

    A. A. Yamin

    2013-08-01

    Full Text Available The aims of this experiment was to study the inhibition effect of betel leaf meal (BLM addition into concentrate diet on mastitis causing bacteria and on rumen fermentation condition. The study consisted of five dietary treatments of BLM level in concentrate feed, i.e., 0%, 2%, 4%, 6%, and 8% and four replicates of each treatment. The treatment diets together with napier grass in ratio of 40 : 60 were fermented using rumen liquor. All treatments were examined their antibacterial activity before and after fermentation. After four hours fermentation, supernatant of each samples were analyzed for VFA, NH3, number of bacteria and protozoa. Dry matter (DM and organic matter (OM digestibility were analyzed after 48 h fermentation. The results showed that before fermentation, 8% BLM addition caused the bigest (P<0.05 inhibition diameter of Staphylococcus spp. growth compared to other lower levels. However after fermentation there were no significant differences among the addition levels of BLM. Two per cent of BLM addition produced higher VFA (P<0.05 than the other addition levels. Ammonia concentration, dry matter (DM and organic matter (OM digestibility were not different among the treatments. Addition of BLM significantly (P<0.01 decreased protozoa number, but did not affect bacterial count. It is concluded that the addition of 2% BLM in concentrate feed can be used effectively to inhibit the growth of mastitis causing bacteria (Staphylococcus spp. and does not disturb rumen fermentation condition.

  13. Effects of electron beam irradiation on chemical composition, antinutritional factors, ruminal degradation and in vitro protein digestibility of canola meal

    Energy Technology Data Exchange (ETDEWEB)

    Taghinejad-Roudbaneh, M., E-mail: mtaghinejad@iaut.ac.i [Department of Animal Science, Faculty of Agriculture, Islamic Azad University, Tabriz Branch, P.O. Box 51589, Tabriz (Iran, Islamic Republic of); Ebrahimi, S.R. [Department of Animal Science, Faculty of Agriculture, Shahr-e-Qods Branch, Islamic Azad University, P.O. Box 37515-374, Shahr-e-Qods (Iran, Islamic Republic of); Azizi, S. [Department of Clinical Sciences, Faculty of Veterinary Medicine, Urmia University, P.O. Box 57155-1177, Urmia (Iran, Islamic Republic of); Shawrang, P. [Nuclear Science and Technology Research Institute, Agricultural, Medical and Industrial Research School, Atomic Energy Organization of Iran, P.O. Box 31485-498, Karaj (Iran, Islamic Republic of)

    2010-12-15

    The aim of the present study was to determine the impact of electron beam (EB) irradiation at doses of 15, 30 and 45 kGy on the nutritional value of canola meal. The phytic acid and total glucosinolate content of EB-irradiated canola meal decreased as irradiation doses increased (P<0.01). From in situ results, irradiation of canola meal at doses of 45 kGy decreased (P<0.05) the effective degradibility of crude protein (CP) by 14%, compared with an untreated sample. In vitro CP digestibility of EB-irradiated canola meal at doses of 15 and 30 kGy was improved (P<0.05). Electrophoresis results showed that napin and cruciferin sub-units of 30 and 45 kGy EB-irradiated canola meal were more resistant to degradation, compared with an untreated sample. Electron beam irradiation was effective in protecting CP from ruminal degradation and reducing antinutritional factors of irradiated canola meal.

  14. Effects of electron beam irradiation on chemical composition, antinutritional factors, ruminal degradation and in vitro protein digestibility of canola meal

    Science.gov (United States)

    Taghinejad-Roudbaneh, M.; Ebrahimi, S. R.; Azizi, S.; Shawrang, P.

    2010-12-01

    The aim of the present study was to determine the impact of electron beam (EB) irradiation at doses of 15, 30 and 45 kGy on the nutritional value of canola meal. The phytic acid and total glucosinolate content of EB-irradiated canola meal decreased as irradiation doses increased ( P<0.01). From in situ results, irradiation of canola meal at doses of 45 kGy decreased ( P<0.05) the effective degradibility of crude protein (CP) by 14%, compared with an untreated sample. In vitro CP digestibility of EB-irradiated canola meal at doses of 15 and 30 kGy was improved ( P<0.05). Electrophoresis results showed that napin and cruciferin sub-units of 30 and 45 kGy EB-irradiated canola meal were more resistant to degradation, compared with an untreated sample. Electron beam irradiation was effective in protecting CP from ruminal degradation and reducing antinutritional factors of irradiated canola meal.

  15. Effect of Biostimulation Using Sewage Sludge, Soybean Meal, and Wheat Straw on Oil Degradation and Bacterial Community Composition in a Contaminated Desert Soil

    Science.gov (United States)

    Al-Kindi, Sumaiya; Abed, Raeid M. M.

    2016-01-01

    Waste materials have a strong potential in the bioremediation of oil-contaminated sites, because of their richness in nutrients and their economical feasibility. We used sewage sludge, soybean meal, and wheat straw to biostimulate oil degradation in a heavily contaminated desert soil. While oil degradation was assessed by following the produced CO2 and by using gas chromatography–mass spectrometry (GC–MS), shifts in bacterial community composition were monitored using illumina MiSeq. The addition of sewage sludge and wheat straw to the desert soil stimulated the respiration activities to reach 3.2–3.4 times higher than in the untreated soil, whereas the addition of soybean meal resulted in an insignificant change in the produced CO2, given the high respiration activities of the soybean meal alone. GC–MS analysis revealed that the addition of sewage sludge and wheat straw resulted in 1.7–1.8 fold increase in the degraded C14 to C30 alkanes, compared to only 1.3 fold increase in the case of soybean meal addition. The degradation of ≥90% of the C14 to C30 alkanes was measured in the soils treated with sewage sludge and wheat straw. MiSeq sequencing revealed that the majority (76.5–86.4% of total sequences) of acquired sequences from the untreated soil belonged to Alphaproteobacteria, Gammaproteobacteria, and Firmicutes. Multivariate analysis of operational taxonomic units placed the bacterial communities of the soils after the treatments in separate clusters (ANOSIM R = 0.66, P = 0.0001). The most remarkable shift in bacterial communities was in the wheat straw treatment, where 95–98% of the total sequences were affiliated to Bacilli. We conclude that sewage sludge and wheat straw are useful biostimulating agents for the cleanup of oil-contaminated desert soils. PMID:26973618

  16. Effect of Biostimulation Using Sewage Sludge, Soybean Meal, and Wheat Straw on Oil Degradation and Bacterial Community Composition in a Contaminated Desert Soil.

    Science.gov (United States)

    Al-Kindi, Sumaiya; Abed, Raeid M M

    2016-01-01

    Waste materials have a strong potential in the bioremediation of oil-contaminated sites, because of their richness in nutrients and their economical feasibility. We used sewage sludge, soybean meal, and wheat straw to biostimulate oil degradation in a heavily contaminated desert soil. While oil degradation was assessed by following the produced CO2 and by using gas chromatography-mass spectrometry (GC-MS), shifts in bacterial community composition were monitored using illumina MiSeq. The addition of sewage sludge and wheat straw to the desert soil stimulated the respiration activities to reach 3.2-3.4 times higher than in the untreated soil, whereas the addition of soybean meal resulted in an insignificant change in the produced CO2, given the high respiration activities of the soybean meal alone. GC-MS analysis revealed that the addition of sewage sludge and wheat straw resulted in 1.7-1.8 fold increase in the degraded C14 to C30 alkanes, compared to only 1.3 fold increase in the case of soybean meal addition. The degradation of ≥90% of the C14 to C30 alkanes was measured in the soils treated with sewage sludge and wheat straw. MiSeq sequencing revealed that the majority (76.5-86.4% of total sequences) of acquired sequences from the untreated soil belonged to Alphaproteobacteria, Gammaproteobacteria, and Firmicutes. Multivariate analysis of operational taxonomic units placed the bacterial communities of the soils after the treatments in separate clusters (ANOSIM R = 0.66, P = 0.0001). The most remarkable shift in bacterial communities was in the wheat straw treatment, where 95-98% of the total sequences were affiliated to Bacilli. We conclude that sewage sludge and wheat straw are useful biostimulating agents for the cleanup of oil-contaminated desert soils.

  17. A Novel Hemp Seed Meal Protein Hydrolysate Reduces Oxidative Stress Factors in Spontaneously Hypertensive Rats

    Directory of Open Access Journals (Sweden)

    Abraham T. Girgih

    2014-12-01

    Full Text Available This report shows the antioxidant effects of a hemp seed meal protein hydrolysate (HMH in spontaneously hypertensive rats (SHR. Defatted hemp seed meal was hydrolyzed consecutively with pepsin and pancreatin to yield HMH, which was incorporated into rat feed as a source of antioxidant peptides. Young (8-week old SHRs were divided into three groups (8 rats/group and fed diets that contained 0.0%, 0.5% or 1.0% (w/w HMH for eight weeks; half of the rats were sacrificed for blood collection. After a 4-week washout period, the remaining 20-week old SHRs were fed for an additional four weeks and sacrificed for blood collection. Plasma total antioxidant capacity (TAC and superoxide dismutase (SOD, catalase (CAT and total peroxides (TPx levels were determined. Results showed that plasma TAC, CAT and SOD levels decreased in the older 20-week old SHRs when compared to the young SHRs. The presence of HMH in the diets led to significant (p < 0.05 increases in plasma SOD and CAT levels in both young and adult SHR groups; these increases were accompanied by decreases in TPx levels. The results suggest that HMH contained antioxidant peptides that reduced the rate of lipid peroxidation in SHRs with enhanced antioxidant enzyme levels and total antioxidant capacity.

  18. A novel hemp seed meal protein hydrolysate reduces oxidative stress factors in spontaneously hypertensive rats.

    Science.gov (United States)

    Girgih, Abraham T; Alashi, Adeola M; He, Rong; Malomo, Sunday A; Raj, Pema; Netticadan, Thomas; Aluko, Rotimi E

    2014-12-01

    This report shows the antioxidant effects of a hemp seed meal protein hydrolysate (HMH) in spontaneously hypertensive rats (SHR). Defatted hemp seed meal was hydrolyzed consecutively with pepsin and pancreatin to yield HMH, which was incorporated into rat feed as a source of antioxidant peptides. Young (8-week old) SHRs were divided into three groups (8 rats/group) and fed diets that contained 0.0%, 0.5% or 1.0% (w/w) HMH for eight weeks; half of the rats were sacrificed for blood collection. After a 4-week washout period, the remaining 20-week old SHRs were fed for an additional four weeks and sacrificed for blood collection. Plasma total antioxidant capacity (TAC) and superoxide dismutase (SOD), catalase (CAT) and total peroxides (TPx) levels were determined. Results showed that plasma TAC, CAT and SOD levels decreased in the older 20-week old SHRs when compared to the young SHRs. The presence of HMH in the diets led to significant (p < 0.05) increases in plasma SOD and CAT levels in both young and adult SHR groups; these increases were accompanied by decreases in TPx levels. The results suggest that HMH contained antioxidant peptides that reduced the rate of lipid peroxidation in SHRs with enhanced antioxidant enzyme levels and total antioxidant capacity.

  19. Effect of different protein types on second meal postprandial glycaemia in normal weight and normoglycemic subjects

    Directory of Open Access Journals (Sweden)

    Winder Tadeu Silva Ton

    2014-03-01

    Full Text Available Background: Diabetes mellitus is a global epidemic affecting 346 million people in the world. The glycemic control is the key for diabetes prevention and management. Some proteins can stimulate insulin release and modulate glycemic response. Objectives: To assess the effect of the consumption of different types of protein (whey protein, soy protein and egg white on a second meal postprandial glycaemia in normal weight and normoglycemic subjects. Methodology: Randomized crossover clinical trial. After an overnight fast of 12-hours, ten subjects attended the laboratory to drink one of the protein shakes (whey, soy or egg white or the control drink. Thirty minutes later, the subjects consumed a glucose solution (25 g glucose. Glycemic response was monitored at times 0 (before glucose solution and 15, 30, 45, 60, 90 and 120 min (after glucose solution consumption. Incremental area under the glycemic curve (iAUC was calculated by the trapezoidal method. Furthermore, glycemic response was assessed by a new method using iG equation. Results: Compared with control, whey and soy protein drinks reduced postprandial iAUC in 56.5% (p = 0.004 and 44.4% (p = 0.029, respectively. Whey protein was the only protein capable of avoiding great fluctuations and a peak in postprandial glycemia. The assessment of glycemic response by iG equation showed positive correlation with iAUC (Pearson 0.985, p < 0.05. Conclusion: The consumption of whey and soy protein 30 minutes before a glucose load resulted in lower iAUC compared with control drink. Whey protein maintained postprandial glycemia more stable.

  20. Differential effects of dietary protein sources on postprandial low-grade inflammation after a single high fat meal in obese non-diabetic subjects

    Directory of Open Access Journals (Sweden)

    Herzig Karl-Heinz

    2011-10-01

    Full Text Available Abstract Background Obesity is a state of chronic low-grade inflammation. Chronic low-grade inflammation is associated with the pathophysiology of both type-2 diabetes and atherosclerosis. Prevention or reduction of chronic low-grade inflammation may be advantageous in relation to obesity related co-morbidity. In this study we investigated the acute effect of dietary protein sources on postprandial low-grade inflammatory markers after a high-fat meal in obese non-diabetic subjects. Methods We conducted a randomized, acute clinical intervention study in a crossover design. We supplemented a fat rich mixed meal with one of four dietary proteins - cod protein, whey isolate, gluten or casein. 11 obese non-diabetic subjects (age: 40-68, BMI: 30.3-42.0 kg/m2 participated and blood samples were drawn in the 4 h postprandial period. Adiponectin was estimated by ELISA methods and cytokines were analyzed by multiplex assay. Results MCP-1 and CCL5/RANTES displayed significant postprandial dynamics. CCL5/RANTES initially increased after all meals, but overall CCL5/RANTES incremental area under the curve (iAUC was significantly lower after the whey meal compared with the cod and casein meals (P = 0.0053. MCP-1 was initially suppressed after all protein meals. However, the iAUC was significantly higher after whey meal compared to the cod and gluten meals (P = 0.04. Conclusion We have demonstrated acute differential effects on postprandial low grade inflammation of four dietary proteins in obese non-diabetic subjects. CCL5/RANTES initially increased after all meals but the smallest overall postprandial increase was observed after the whey meal. MCP-1 was initially suppressed after all 4 protein meals and the whey meal caused the smallest overall postprandial suppression. Trial Registration ClinicalTrials.gov ID: NCT00863564

  1. Prediction of crude protein digestibility of animal by-product meals for dogs by the protein solubility in pepsin method.

    Science.gov (United States)

    Kawauchi, Iris M; Sakomura, Nilva K; Pontieri, Cristiana F F; Rebelato, Aline; Putarov, Thaila C; Malheiros, Euclides B; Gomes, Márcia de O S; Castrillo, Carlos; Carciofi, Aulus C

    2014-01-01

    Animal by-product meals have large variability in crude protein (CP) content and digestibility. In vivo digestibility procedures are precise but laborious, and in vitro methods could be an alternative to evaluate and classify these ingredients. The present study reports prediction equations to estimate the CP digestibility of meat and bone meal (MBM) and poultry by-product meal (PM) using the protein solubility in pepsin method (PSP). Total tract CP digestibility of eight MBM and eight PM samples was determined in dogs by the substitution method. A basal diet was formulated for dog maintenance, and sixteen diets were produced by mixing 70 % of the basal diet and 30 % of each tested meal. Six dogs per diet were used to determine ingredient digestibility. In addition, PSP of the MBM and PM samples was determined using three pepsin concentrations: 0·02, 0·002 and 0·0002 %. The CP content of MBM and PM ranged from 39 to 46 % and 57 to 69 %, respectively, and their mean CP digestibility by dogs was 76 (2·4) and 85 (2·6) %, respectively. The pepsin concentration with higher Pearson correlation coefficients with the in vivo results were 0·0002 % for MBM (r 0·380; P = 0·008) and 0·02 % for PM (r 0·482; P = 0·005). The relationship between the in vivo and in vitro results was better explained by the following equations: CP digestibility of MBM = 61·7 + 0·2644 × PSP at 0·0002 % (P = 0·008; R (2) 0·126); and CP digestibility of PM = 54·1 + 0·3833 × PSP at 0·02 % (P = 0·005; R (2) 0·216). Although significant, the coefficients of determination were low, indicating that the models were weak and need to be used with caution.

  2. Centrosema (Centrosema pubescens leaf meal as a protein supplement for broiler chicks production

    Directory of Open Access Journals (Sweden)

    Friday Chima NWORGU

    2015-10-01

    Full Text Available Present study was conducted to find out the potential Centrosema (Centrosema pubescens leaf meal as a protein supplement for the broiler chicks production. For this, Ninety unsexed one week old Anak 2000 broiler chicks were used. These selected chicks were randomly allotted to 5 dietary treatments i.e. A (Centrosema free diet, B (3%, C (6%, D (9% and E (12% with different concentration of C. pubescens leaf meal (CLM. Each treatment was replicated 3 times with 6 birds per replicate. This CLM mainly used to replaced groundnut cake and soybean in the diets. Water and feeds were served adlibitum. The results of study revealed that dietary supplementation of CLM significantly (P<0.05 and progressively depressed final body weight, weight gain and feed conversion ratio unlike water and feed intakes. Dietary inclusion of 6-12% CLM for broiler chicks reduced weight gain averagely by 12.96% compared to control. The cost of feed per kg live weight gain was N91.86, N96.04 and NI07.59/kg for control, 3 and 12%, respectively. Profit margin was highest in control (N4.11 and birds placed on 3% CLM (N2.66 per bird compared to those fed 9.0-12.0% CLM dietary inclusion, in which average loss was N20.39 per bird. Hence results of study clearly advised that CLM can be add as protein supplements but it should not include more than 3% in the diet of broiler chicks

  3. Behavior of Escherichia coli bacteria in whey protein and corn meal during twin screw extrusion processing at different temperatures

    Science.gov (United States)

    Many studies on the development of new and/ or value added nutritional meal corn and whey protein isolates for US consumers have been reported. However, information on the effect of treatment parameters on microbial safety of foods extruded below 100 deg C is limited. In this study, we investigated ...

  4. A controlled trial of protein enrichment of meal replacements for weight reduction with retention of lean body mass

    Directory of Open Access Journals (Sweden)

    Bowerman Susan

    2008-08-01

    Full Text Available Abstract Background While high protein diets have been shown to improve satiety and retention of lean body mass (LBM, this study was designed to determine effects of a protein-enriched meal replacement (MR on weight loss and LBM retention by comparison to an isocaloric carbohydrate-enriched MR within customized diet plans utilizing MR to achieve high protein or standard protein intakes. Methods Single blind, placebo-controlled, randomized outpatient weight loss trial in 100 obese men and women comparing two isocaloric meal plans utilizing a standard MR to which was added supplementary protein or carbohydrate powder. MR was used twice daily (one meal, one snack. One additional meal was included in the meal plan designed to achieve individualized protein intakes of either 1 2.2 g protein/kg of LBM per day [high protein diet (HP] or 2 1.1 g protein/kg LBM/day standard protein diet (SP. LBM was determined using bioelectrical impedance analysis (BIA. Body weight, body composition, and lipid profiles were measured at baseline and 12 weeks. Results Eighty-five subjects completed the study. Both HP and SP MR were well tolerated, with no adverse effects. There were no differences in weight loss at 12 weeks (-4.19 ± 0.5 kg for HP group and -3.72 ± 0.7 kg for SP group, p > 0.1. Subjects in the HP group lost significantly more fat weight than the SP group (HP = -1.65 ± 0.63 kg; SP = -0.64 ± 0.79 kg, P = 0.05 as estimated by BIA. There were no significant differences in lipids nor fasting blood glucose between groups, but within the HP group a significant decrease in cholesterol and LDL cholesterol was noted at 12 weeks. This was not seen in the SP group. Conclusion Higher protein MR within a higher protein diet resulted in similar overall weight loss as the standard protein MR plan over 12 weeks. However, there was significantly more fat loss in the HP group but no significant difference in lean body mass. In this trial, subject compliance with both the

  5. Advances in animal and plant protein sources in place of fish meal%动植物蛋白源替代鱼粉研究进展

    Institute of Scientific and Technical Information of China (English)

    周歧存; 麦康森; 刘永坚; 谭北平

    2005-01-01

    With the fast development of aquaculture, fish meal needs increased in recent years, however the quantity of fish catching decreases gradually. Fishmeal is a limited feed resource, and serious concem exists on the future availability of this feedstuff for incorporation in fish diets. Undoubtedly, fish meal is well recognized as the best dietary protein source for most marine carnivorous fishes which required high dietary protein levels compared to omnivorous or herbivorous fish. Fishmeal is known for their high content of essential amino acids and fatty acids, low carbohydrates, high digestibility, low levels of anti-nutritional factors (for fresh fish meal) and is a very good source of minerals and is highly palatable. Thus fish meal is in high demand as the protein source for many formulated diets. However, production of fish meal consumes approximately 35 % of the total global fish catch, and the increasing price and potentially unstable supply in the market could be limiting factors for marine fish culture. There have been strong efforts to define and develop cost-effective protein sources that can, at least partly, substitute for expensive high-quality fish meals in least-cost feed formulations. The search for fish meal substitutes and altemative dietary protein sources is an international research priority that could be of considerable economic advantages. Therefore it is urgent task to find animal and plant protein sources in place of fish meal. Among these, plant feedstuffs have received most attention in recent years, but due to their amino acid unbalances, .presence of anti-nutritional factors and low palatability, a high level of replacement of fish meal with plant feedstuffs in omnivorous fish is generally not well accepted. This paper reviews the research status for other protein sources replacing fish meal based on available information in the literature. Animal and plant protein sources nutrient values are evaluated from the aspect of digestibility

  6. Effect of biostimulation using sewage sludge, soybean meal and wheat straw on oil degradation and bacterial community composition in a contaminated desert soil

    Directory of Open Access Journals (Sweden)

    Sumaiya eAl-Kindi

    2016-03-01

    Full Text Available Waste materials have a strong potential in the bioremediation of oil-contaminated sites, because of their richness in nutrients and their economical feasibility. We used sewage sludge, soybean meal and wheat straw to biostimulate oil degradation in a heavily contaminated desert soil. While oil degradation was assessed by following the produced CO2 and by using gas chromatography-mass spectrometry (GC-MS, shifts in bacterial community composition were monitored using illumina MiSeq. The addition of sewage sludge and wheat straw to the desert soil stimulated the respiration activities more than the addition of soybean meal. GC-MS analysis revealed that the addition of addition of sewage sludge and wheat straw resulted in 1.7 to 1.8 fold increase in the degraded C14 to C30 alkanes, compared to only 1.3 fold increase in the case of soybean meal addition. The degradation of ≥ 90% of the C14 to C30 alkanes were measured in the soils treated with sewage sludge and wheat straw. MiSeq sequencing revealed that the majority (76.5-86.4% of total sequences of acquired sequences from the original soil belonged to Alphaproteobacteria, Gammaproteobacteria and Firmicutes. Multivariate analysis of operational taxonomic units (OTUs placed the bacterial communities of the soils after the treatments in separate clusters (ANOSIM R=0.66, P=0.0001. The most remarkable shift in bacterial communities was in the wheat straw treatment, where 95-98% of the total sequences belonging to Bacilli. We conclude that sewage sludge and wheat straw are useful biostimulating agents for the cleanup of oil-contaminated desert soils.

  7. Soybean meal substitution with a yeast-derived microbial protein source in dairy cow diets.

    Science.gov (United States)

    Sabbia, J A; Kalscheur, K F; Garcia, A D; Gehman, A M; Tricarico, J M

    2012-10-01

    The objective of this study was to examine the effects substituting soybean meal with a yeast-derived microbial protein (YMP) on rumen and blood metabolites, dry matter intake, and milk production of high-producing dairy cows. Sixteen Holstein cows (12 multiparous and 4 primiparous), 93 ± 37 DIM (mean ± SD) at the beginning of the experiment, were used in a 4×4 Latin square design with four 28-d periods. Cows were blocked by parity and production, with 1 square consisting of 4 animals fitted with rumen cannulas. Basal diets, formulated for 16.1% crude protein and 1.56 Mcal/kg of net energy for lactation, contained 40% corn silage, 20% alfalfa hay, and 40% concentrate mix. During each period, cows were fed 1 of 4 treatment diets corresponding to YMP (DEMP; Alltech Inc., Nicholasville, KY) concentrations of 0, 1.14, 2.28, and 3.41% DM. Soybean meal (44% CP) was replaced by YMP to attain isonitrogenous and isoenergetic diets. Dietary treatments had no effect on pH and on most ruminal volatile fatty acid concentrations, with the exception of isovalerate, which decreased linearly with the addition of YMP. Rumen ammonia concentration decreased linearly, whereas free amino acids, total amino acid nitrogen, and soluble proteins weighing more than 10 kDa showed a cubic response on rumen N fractionation. A quadratic response was observed in oligopeptides that weighed between 3 and 10 kDa and peptides under 3kDa when expressed as percentages of total amino acids and total nitrogen. Although nonesterified fatty acid concentration in blood did not differ between treatments, β-hydroxybutyrate and plasma glucose increased linearly as YMP increased. Dry matter intake showed a cubic effect, where cows fed 1.14, and 3.41% YMP had the highest intake. Milk production was not affected by YMP, whereas a trend was observed for a quadratic increase for 4% fat-corrected milk and energy-corrected milk. Medium- and long-chain fatty acid concentrations in milk increased quadratically

  8. Effect of ash content on protein quality of meat and bone meal.

    Science.gov (United States)

    Shirley, R B; Parsons, C M

    2001-05-01

    The effect of ash concentration on amino acid (AA) composition, true AA digestibility, and protein efficiency ratio (PER; weight gain per unit of protein intake) of meat and bone meal (MBM) was evaluated. Commercially rendered MBM samples containing 16 to 44% ash were obtained from two sources. Additional samples of MBM varying in ash from 9 to 63% were obtained by chloroform floatation or lab screening of a beef crax sample. Protein quality of selected MBM samples was assessed by determining true AA digestibility using the precision-fed cecectomized rooster assay and by a PER chick growth assay wherein chicks were fed 10% CP diets containing a MBM as the only source of dietary protein from 8 to 18 d of age. Increases in Ala, Pro, Gly, and Arg as a percentage of CP were observed in all MBM samples as ash percentage increased, with Pro and Gly accounting for most of the increase. In contrast, the levels (% of CP) of all essential AA, other than Arg, decreased as ash level increased. For example, Lys concentrations per unit of CP decreased from 5.7 to 4.0% as ash increased from 9 to 63%. There was little or no effect of ash content on AA digestibility of MBM varying in ash from 9 to 44%. The PER of MBM markedly decreased from 3.34 to 0.72 as ash increased from 16 to 44%, and most of the effects of ash on PER were not due to differences in dietary Ca and P levels. The results indicate that the reduction in protein quality of MBM as ash content increases is almost entirely due to a decrease in analyzed essential AA per unit of CP, not a decrease in digestibility of AA.

  9. Bioavailability of crude protein and lipid from biofloc meals produced in an activated sludge system for white shrimp, Litopenaeus vannamei

    Directory of Open Access Journals (Sweden)

    Hassan Sabry Neto

    2015-08-01

    Full Text Available The present study compared the bioavailability of crude protein and lipid from biofloc meals generated with an activated sludge system using two water sources: wastewater from shrimp experimental culture (BFL-W and, artificially, using clean seawater (BFL-C. The sludge system operated by chemical and organic fertilization three times per week. Sampling of bioflocs occurred every two days during 81 days. To evaluate digestibility, each type of biofloc meal was incorporated into a reference diet (REF at 300 g/kg. Another diet acted as a negative control (NEG by using fish waste meal. The apparent digestibility of bioflocs was estimated by the indirect method using chromic oxide (Cr2O3 as the inert marker at 10 g/kg of the diet. Juvenile L. vannamei of 5.09±0.79 g (n = 440 were stocked at 10 shrimp/tank in 44 tanks of 61 L each that operated under a water recirculating regime. Biofloc meals contained a high ash content (591.0-649.2 g/kg combined with a low crude protein content (95.9-137.3 g/kg. After 26 days, shrimp achieved a final survival of 93.2±0.8% and a biomass gain of 37.1±1.8 g/tank. Final shrimp body weight ranged from 9.01±0.15 to 9.45±0.13 g. The apparent digestibility coefficient (ADC of crude protein in the biofloc produced from BFL-W, BFL-C and fish waste meal (NEG reached 26.0, 25.7, and 64.1%, respectively. Similarly, the lipid ADC was 78.9, 67.9, and 85.8%, respectively. This study indicated that biofloc meals had a low protein availability for L. vannamei. However, although low levels of lipid were present, it proved to be available for the species. The dietary inclusion of biofloc meal appears to have a growth-promoting effect on shrimp, which may be associated with trace minerals, or other nutrients not identified in this study.

  10. The potential of snail (Pila leopoldvillensis meal as protein supplement in broiler diets

    Directory of Open Access Journals (Sweden)

    Barcelo, PM.

    1991-01-01

    Full Text Available The chemical analysis revealed that raw golden snail meal (R. GSM had 53.22 %, 6.01 % and 0.49 % crudeprotein, calcium and phosphorus respectively. The cooked golden snail meal (C. GSM had 52.25 % CP, 6.51 % Ca and 0.41 % P. Birds fed with fish meal (control had significantly the highest feed conversion ratio followed by the birds fed the (C. GSM (P 0.05. The gain in weight of the birds fed the (C. GSM had comparable gain in weight with the birds fed the control diet. There were no significant differences observed in a second experiment because the somme feed ingredients had compensated for the deficiency of the nutrients to meet the requirements of the birds. Results reveal that the ingredients of golden snail meal in broiler diets is just as good as incorporating the imported fish meal.

  11. TROPICAL VEGETABLE (AMARANTHUS CRUENTUS LEAF MEAL AS ALTERNATIVE PROTEIN SUPPLEMENT IN BROILER STARTER DIETS: BIONUTRITIONAL EVALUATION

    Directory of Open Access Journals (Sweden)

    A FASUYI

    2008-07-01

    Full Text Available Amaranthus cruentus is a tropical leaf vegetable grown in most tropical regions of the world for its vegetable protein. The fresh matured leaves of the plant were harvested and sun dried until a moisture content of between 12-13% was obtained. The sun dried leaves (Amaranthus cruentus leaf meal, ACLM were milled and analysed for their proximate composition. Crude protein was 23.0%+0.55; crude fat, 5.4%+0.01; crude fibre, 8.8%+0.02; ash, 19.3%+0.01 and gross energy, 3.3+0.01kcal/g all on dry matter basis. Methionine and to a lesser extent, lysine, arginine, leucine and aspartate were high. The ACLM was incorporated into five formulated broiler starter diets at varying inclusion levels. The control diet 1 had no ACLM inclusion. All the six diets including control diet 1 were formulated isocaloric and isonitrogenous and fed to the experimental chicks (n = 540. Birds kept on diet 2 (5% ACLM inclusion level had the best average weight gain (WG of 372.9+29.94g/chick. The feed efficiency (FE value and the protein efficiency ratio (PER for birds on diet 2 were similar (P > 0.05 to values obtained for the reference diet. The nitrogen retention (NR and apparent nitrogen digestibility (AND values obtained for diet 2 were highest at 1.48+0.24gN/chick/day and 63.12%+10.28, respectively. Except for dressed weight and the back of chicken all the organs weights taken were similar (P > 0.05. Haematological examinations were similar (P > 0.05. Results generally indicated that ACLM could be a useful dietary protein source for broiler starter chicks at 5% inclusion level.

  12. Hydrolysis of the amyloid prion protein and nonpathogenic meat and bone meal by anaerobic thermophilic prokaryotes and streptomyces subspecies.

    Science.gov (United States)

    Tsiroulnikov, Kirill; Rezai, Human; Bonch-Osmolovskaya, Elisaveta; Nedkov, Peter; Gousterova, Adriana; Cueff, Valérie; Godfroy, Anne; Barbier, Georges; Métro, François; Chobert, Jean-Marc; Clayette, Pascal; Dormont, Dominique; Grosclaude, Jeanne; Haertlé, Thomas

    2004-10-06

    Transmissible spongiform encephalopathies are caused by accumulation of highly resistant misfolded amyloid prion protein PrPres and can be initiated by penetration of such pathogen molecules from infected tissue to intact organism. Decontamination of animal meal containing amyloid prion protein is proposed thanks to the use of proteolytic enzymes secreted by thermophilic bacteria Thermoanaerobacter, Thermosipho, and Thermococcus subsp. and mesophilic soil bacteria Streptomyces subsp. Keratins alpha and beta, which resemble amyloid structures, were used as the substrates for the screening for microorganisms able to grow on keratins and producing efficient proteases specific for hydrolysis of beta-sheeted proteic structures, hence amyloids. Secretion of keratin-degrading proteases was evidenced by a zymogram method. Enzymes from thermophilic strains VC13, VC15, and S290 and Streptomyces subsp. S6 were strongly active against amyloid recombinant ovine prion protein and animal meal proteins. The studied proteases displayed broad primary specificities hydrolyzing low molecular mass peptide model substrates. Strong amyloidolytic activity of detected proteases was confirmed by experiments of hydrolysis of PrPres in SAFs produced from brain homogenates of mice infected with the 6PB1 BSE strain. The proteases from Thermoanaerobacter subsp. S290 and Streptomyces subsp. S6 are the best candidates for neutralization/elimination of amyloids in meat and bone meal and other protein-containing substances and materials.

  13. Infectious Keratitis: Secreted Bacterial Proteins That Mediate Corneal Damage

    Directory of Open Access Journals (Sweden)

    Mary E. Marquart

    2013-01-01

    Full Text Available Ocular bacterial infections are universally treated with antibiotics, which can eliminate the organism but cannot reverse the damage caused by bacterial products already present. The three very common causes of bacterial keratitis—Pseudomonas aeruginosa, Staphylococcus aureus, and Streptococcus pneumoniae—all produce proteins that directly or indirectly cause damage to the cornea that can result in reduced vision despite antibiotic treatment. Most, but not all, of these proteins are secreted toxins and enzymes that mediate host cell death, degradation of stromal collagen, cleavage of host cell surface molecules, or induction of a damaging inflammatory response. Studies of these bacterial pathogens have determined the proteins of interest that could be targets for future therapeutic options for decreasing corneal damage.

  14. Expression, Solubilization, and Purification of Bacterial Membrane Proteins.

    Science.gov (United States)

    Jeffery, Constance J

    2016-02-02

    Bacterial integral membrane proteins play many important roles, including sensing changes in the environment, transporting molecules into and out of the cell, and in the case of commensal or pathogenic bacteria, interacting with the host organism. Working with membrane proteins in the lab can be more challenging than working with soluble proteins because of difficulties in their recombinant expression and purification. This protocol describes a standard method to express, solubilize, and purify bacterial integral membrane proteins. The recombinant protein of interest with a 6His affinity tag is expressed in E. coli. After harvesting the cultures and isolating cellular membranes, mild detergents are used to solubilize the membrane proteins. Protein-detergent complexes are then purified using IMAC column chromatography. Support protocols are included to help select a detergent for protein solubilization and for use of gel filtration chromatography for further purification.

  15. Growh performance, nitrogen balance and urinary purine derivatives in growing-furring mink (Mustela vison) fed bacterial protein produced from natural gas

    DEFF Research Database (Denmark)

    Ahlstrøm, Ø.; Tauson, Anne-Helene; Hellwing, Anne Louise Frydendahl

    2006-01-01

    A bacterial protein meal (BPM), containing 70% crude protein and produced on natural gas, was evaluated versus fish meal as protein source for mink in the growing-furring period (June 29-November 26). BPM, rich in nucleic acids, accounted for 0 (control), 20 and 40% of dietary crude protein......, except for males on the 8% BPM diet. Balance experiments carried out with 18 and 28 weeks old males, revealed similar digestibility of main nutrients except for fat that were reduced with BPM inclusion. N-retentions were similar for the dietary groups. Daily excretion of urine was lower with the 8% BPM...... not affected by diet, except for shorter hair length with inclusion of BPM. In conclusion, the experiment showed that BPM can account for 40% of dietary protein in growing-furring mink without negative effects on N metabolism, body weight gain or fur quality....

  16. The Impact of Rendered Protein Meal Oxidation Level on Shelf-Life, Sensory Characteristics, and Acceptability in Extruded Pet Food

    Science.gov (United States)

    Chanadang, Sirichat; Koppel, Kadri; Aldrich, Greg

    2016-01-01

    Simple Summary Sensory analysis was used to determine the changes due to the storage time on extruded pet food prepared from two different rendered protein meals: (i) beef meat and bone meal (BMBM); (ii) chicken byproduct meal (CPBM). Extrusion is a process where feed is pressed through a die in order to create shapes and increase digestibility. Descriptive sensory analysis using a human panel found an increase in undesirable sensory attributes (e.g., oxidized oil, rancid) in extruded pet food over storage time, especially the one prepared from chicken by product meal without antioxidants. The small increase in oxidized and rancid aromas of BMBM samples did not affect pet owners’ acceptability of the products. CPBM samples without antioxidants showed a notable increase in oxidized and rancid aroma over storage time and, thus, affected product acceptability negatively. This finding indicated that human sensory analysis can be used as a tool to track the changes of pet food characteristics due to storage, as well as estimate the shelf-life of the products. Abstract Pet foods are expected to have a shelf-life for 12 months or more. Sensory analysis can be used to determine changes in products and to estimate products’ shelf-life. The objectives of this study were to (1) investigate how increasing levels of oxidation in rendered protein meals used to produce extruded pet food affected the sensory properties and (2) determine the effect of shelf-life on pet owners’ acceptability of extruded pet food diet formulated without the use of preservative. Pet food diets contained beef meat bone meal (BMBM) and chicken byproduct meal (CBPM) in which the oxidation was retarded with ethoxyquin, mixed tocopherols, or none at all, and then extruded into dry pet foods. These samples represented low, medium, and high oxidation levels, respectively. Samples were stored for 0, 3, 6, 9, and 12 months at ambient temperature. Each time point, samples were evaluated by six highly

  17. [Response of pancreatic polypeptide to a protein rich meal in insulin non dependent diabetes melitus and autonomic neuropathy].

    Science.gov (United States)

    Kostić, N; Zamaklar, M; Novaković, R; Stajić, S

    1994-01-01

    Parasympathetic function and plasma hPP response to a protein rich meal were evaluated in 105 insulin non-dependent diabetic patients: 20 with autonomic neuropathy (group A), diagnosed by Clonidin test; 35 patients with neurophysiological evidence of polyneuropath (group B); 30 patients with autonomic neuropathy and polineuropathy (group C), and 20 patients without any sign of neuropathy (group D). Plasma hPP levels were determined by RIA using an anti-hPP antiserum, kindly provided by Prof. S. R. Bloom (Hammersmith Hospital, London). Blood was taken at 0. 45 and 60 minutes after the beginning of the meal. In groups A and C, the meal induced hPP increase was significantly lower than in group D (p 0.001). All group B patients had a marked increase in the peptide, similar to that in diabetics without neuropathy. These result ssuggest that diabetic autonomic neuropathy is associated with dysfunction of hPP secretion, and that the evaluation of hPP response to test meal may be a sensitive and simple method for the assessment of paraympathetic impairment in diabetes.

  18. Bacterial protein toxins in human cancers.

    Science.gov (United States)

    Rosadi, Francesca; Fiorentini, Carla; Fabbri, Alessia

    2016-02-01

    Many bacteria causing persistent infections produce toxins whose mechanisms of action indicate that they could have a role in carcinogenesis. Some toxins, like CDT and colibactin, directly attack the genome by damaging DNA whereas others, as for example CNF1, CagA and BFT, impinge on key eukaryotic processes, such as cellular signalling and cell death. These bacterial toxins, together with other less known toxins, mimic carcinogens and tumour promoters. The aim of this review is to fulfil an up-to-date analysis of toxins with carcinogenic potential that have been already correlated to human cancers. Bacterial toxins-induced carcinogenesis represents an emerging aspect in bacteriology, and its significance is increasingly recognized.

  19. Lack of effect of high-protein vs. high-carbohydrate meal intake on stress-related mood and eating behavior

    Directory of Open Access Journals (Sweden)

    Lemmens Sofie G

    2011-12-01

    Full Text Available Abstract Background Consumption of meals with different macronutrients, especially high in carbohydrates, may influence stress-related eating behavior. We aimed to investigate whether consumption of high-protein vs. high-carbohydrate meals influences stress-related mood, food reward, i.e. 'liking' and 'wanting', and post-meal energy intake. Methods Participants (n = 38, 19m/19f, age = 25 ± 9 y, BMI = 25.0 ± 3.3 kg/m2 came to the university four times, fasted, once for a stress session receiving a high-protein meal, once for a rest session receiving a high-protein meal, once for a stress session receiving a high-carbohydrate meal and once for a rest session receiving a high-carbohydrate meal (randomized cross-over design. The high-protein and high-carbohydrate test meals (energy percentage protein/carbohydrate/fat 65/5/30 vs. 6/64/30 matched for energy density (4 kJ/g and daily energy requirements (30%. Stress was induced using an ego-threatening test. Pre- and post-meal 'liking' and 'wanting' (for bread, filling, drinks, dessert, snacks, stationery (non-food alternative as control was measured by means of a computer test. Following the post-meal 'wanting' measurement, participants received and consumed their wanted food items (post-meal energy intake. Appetite profile (visual analogue scales, mood state (Profile Of Mood State and State Trait Anxiety Inventory questionnaires, and post-meal energy intake were measured. Results Participants showed increased feelings of depression and anxiety during stress (P Conclusions Consumption of a high-protein vs. high-carbohydrate meal appears to have limited impact on stress-related eating behavior. Only participants with high disinhibition showed decreased subsequent 'wanting' and energy intake during rest; this effect disappeared under stress. Acute stress overruled effects of consumption of high-protein foods. Trial registration The study was registered in the Dutch Trial Register (NTR1904. The

  20. Using Nigella sativa meal as a substitute source for vegetable protein in rations of native growing calves

    Directory of Open Access Journals (Sweden)

    A. K. Nasser

    2011-01-01

    Full Text Available The present study was carried out on 15 growing local bull calves of about 150-200 kg, live body weight and 10-12 months old to investigate the effect of substituting soyabean meal as concentrate feed mixture protein by Nigella sativa meal (NSM at 0 , 60 and 100%. Animals were divided into 3 groups of 5 calves each, according to their live body weight for performing feeding trials. All groups of animals were fed iso-nitrogen (15% CP and iso-caloric (2.7 Mcal/kg. ME diets. Experimental rations were offered at 2.5% of live body weight with 1% of wheat straw. At the end of the feeding trial, which lasted for 105 days, blood samples were collected from all calves to estimate the total protein, albumin, globulin, triglyceride and cholesterol. Digestibility trial was carried out on three animals of each group to investigate the nutritional value of rations. Economical study was also carried out on experimental animals. Results indicated that there was an improvement in feed intake by 13 and 14% for groups fed a ration containing NSM compared with the group fed the control one. No significant differences were between groups of calves in total body weight gain and blood parameters. The feed conversion ratio improved by 12% for the group of calves fed control ration as compared with other groups. The same cost of producing 1 kg live body weight gain was found. Substituting soybean meal protein at 60 and 100% by NSM protein significantly improved crude fiber, ether extract, EE, and the values of digestion coefficient. It was concluded that NSM could be substituted instead of soyabean meal for growing local calves with out adverse effects on their performance.

  1. Sunflower meal as a major vegetable protein source in layers' ration.

    Science.gov (United States)

    Mirza, M A; Sial, M A

    1992-01-01

    An experiment was conducted with Starcross layers to evaluate the replacement value of sunflower meal (SFM) for cotton seed meal (CSM) and sesame meal (SM). The birds (aged 24 weeks) were given 4 isonitrogenous and isocaloric rations containing 0, 5, 10 and 15% dehulled sunflower meal. The substitution of SFM for CSM and SM did not generally affect the egg production, feed consumption, feed conversion nor did it have any effect on the quality of eggs as measured by Haugh Units (HU) and yolk index. Egg shell thickness, however, improved by increasing dietary levels of SFM. The feed costs per hen were generally lower for the SFM group since SFM was cheaper than CSM and SM.

  2. Improvement of protein extraction from sunflower meal by hydrolysis with alcalase

    Directory of Open Access Journals (Sweden)

    Vioque, J.

    2003-12-01

    Full Text Available Extraction of proteins from defatted sunflower meal has been improved by addition of the protease alcalase during alkaline extraction. This method offers several additional advantages as compared to the traditional alkaline extraction without alcalase, which is usually carried out after a sedimentation/flotation step to remove the lignocellulosic fraction. As compared to extraction without alcalase, addition of 0.1% (v/v alcalase improved the yield of protein extraction from 57.5% to 87.4%, providing an extract that is 22% hydrolyzed. In addition, an increment of up to 4.5 times in protein solubility at low pH values is achieved, which correlates with the degree of hydrolysis. The extracts that were obtained in the presence of alcalase had a higher proline and glycine content, suggesting that the protease improves extraction of proline-rich and glycine-rich cell wall proteins that are part of the lignocellulosic fraction. These protein extracts can be directly dried without generation of wastewater, and the resulting fiber-rich material could be used for animal feeding.Se ha mejorado la extracción proteica de la harina desengrasa de girasol mediante la adición de la proteasa alcalasa durante la extracción alcalina. Este método ofrece varias ventajas adicionales en comparación con la extracción alcalina tradicional sin alcalasa, que se desarrolla normalmente mediante un proceso de flotación/sedimentación para retirar la fracción lignocelulósica. En comparación a la extracción sin alcalasa, la adicción de 0.1% (v/v de alcalasa mejora los rendimientos de extracción proteica desde un 57.5% a un 87.4%, dando un extracto con un 22% de grado de hidrólisis. Además se obtiene un incremento de hasta 4.5 veces de la solubilidad proteica a bajos pHs, que se correlaciona con el grado de hidrólisis. Los extractos obtenidos con alcalasa tenían un mayor contenido de prolina y glicina, sugiriendo que la proteasa mejora la extracción de las

  3. Utilization Of Expired Sausage Meal As A Source Of Protein In Feed Formulations For Growth Of Tilapia Oreochromis Sp.

    Directory of Open Access Journals (Sweden)

    Ren Fitriadi

    2015-08-01

    Full Text Available ABSTRACT It has been studied about utilization of expired sausage meal in tilapia Oreochromis sp. feed formulations with the aim to assess the level of the specific growth rate feed conversion ratio and protein efficiency ratio. Five experimental feed contained 25 crude protein in feed which substituted with expired sausage meal as much as A 0 B 10 C 20 D 30 and E 40. Test fish used tilapia Oreochromis sp. Weight 4.5 1.26 gram with a maintenance period of 30 days in a controlled aquarium. The results of this research were the best expired sausage meal dose that can deliver growth rate and feed efficiency was best to feed treatment A. This evidenced by the survival value of 90.00 0.00 for specific growth rate of 1.29 0 09 weight day for a feed conversion ratio of 1.94 0.01 and for protein efficiency ratio of 1.96 0.01.

  4. UTILIZATION OF CORN GLUTEN MEAL AS A PROTEIN SOURCE IN DIETS FOR GILTHEAD SEA BREAM (Sparus aurata L. JUVENILES

    Directory of Open Access Journals (Sweden)

    Murat Yiğit

    2012-01-01

    Full Text Available The utilization of corn gluten meal (CGM was evaluated as a partial fish meal (FM substitute in practical diets for gilthead sea bream juveniles. Four test diets (isonitrogenous and isoca¬loric, 52% protein and 10% lipid, 19 kJ/g diet containing increasing levels of CGM were for¬mulated to replace anchovy meal at levels of 0%, 10%, 20%, and 30%. Triplicate groups of ju¬venile sea bream (initial body weight of 1.5 g were reared in a Recirculating Aquaculture System (RAS over 45 days at 18±2°C. Fish fed a diet containing 10% of CGM showed com¬parable growth performance similar to the control diet containing FM as the sole protein source. No mortality was observed in all treatment groups. Dietary CGM inclusion levels of 20% and 30% showed lower growth performance, feed utilization, and protein efficiency com¬pared to the control and the 10% CGM inclusion diets. However these values were not signifi¬cantly different among fish fed the CGM10 and CGM20 diets. Economical analyses also con¬firmed the growth related experimental results in terms of best profit obtained with the 10% CGM inclusion diet. Results in the present study showed that CGM alone without any amino acid supplements can substitute FM up to 10% with no adverse effects on growth performance, feed utilization, or economical inputs in gilthead sea bream juveniles.

  5. [Elimination of toxic compounds, biological evaluation and partial characterization of the protein from jojoba meal (Simmondsia chinensis [Link] Schneider].

    Science.gov (United States)

    Medina Juárez, L A; Trejo González, A

    1989-12-01

    The purpose of this study was to establish a new methodology to remove the toxic compounds present in jojoba meal and flour. Also, to perform the biological evaluation of the detoxified products and to chemically characterize the protein fractions. Jojoba meal and seed without testa were deffated with hexane and detoxified with a 7:3 isopropanol-water mixture which removed 86% of total phenolic compounds and 100% of simmondsins originally present, the resulting products had reduced bitterness and caused no deaths on experimental animals. NPR values obtained for diets containing such products were significantly different from those obtained with the casein control (p less than 0.05). Total protein was made up of three different fractions: the water-soluble fraction was the most abundant (61.8%), followed by the salt-soluble (23.6%), and the alkaline soluble fraction (14.6%). The nitrogen solubility curves showed that the isoelectric point for the water-soluble and salt-soluble fractions was pH 3.0, while that of the alkaline fraction fell in the range of 4.5-5.0. All fractions had a maximum solubility at pH 7.0. The methodology reported here, offers a viable solution to eliminate toxic compounds from jojoba meal or seeds, and upgrades the potential use of products such as animal feed or raw material for the production of protein isolates.

  6. Dose response of whey protein isolate in addition to a typical mixed meal on blood amino acids and hormonal concentrations.

    Science.gov (United States)

    Forbes, Scott C; McCargar, Linda; Jelen, Paul; Bell, Gordon J

    2014-04-01

    The purpose was to investigate the effects of a controlled typical 1-day diet supplemented with two different doses of whey protein isolate on blood amino acid profiles and hormonal concentrations following the final meal. Nine males (age: 29.6 ± 6.3 yrs) completed four conditions in random order: a control (C) condition of a typical mixed diet containing ~10% protein (0.8 g·kg1), 65% carbohydrate, and 25% fat; a placebo (P) condition calorically matched with carbohydrate to the whey protein conditions; a low-dose condition of 0.8 grams of whey protein isolate per kilogram body mass per day (g·kg1·d1; W1) in addition to the typical mixed diet; or a high-dose condition of 1.6 g·kg1·d1 (W2) of supplemental whey protein in addition to the typical mixed diet. Following the final meal, significant (p whey protein supplementation while no changes were observed in the control and placebo conditions. There was no significant group difference for glucose, insulin, testosterone, cortisol, or growth hormone. In conclusion, supplementing a typical daily food intake consisting of 0.8 g of protein·kg1·d1 with a whey protein isolate (an additional 0.8 or 1.6 g·kg1·d1) significantly elevated total amino acids, EAA, BCAA, and leucine but had no effect on glucose, insulin, testosterone, cortisol, or growth hormone following the final meal. Future acute and chronic supplementation research examining the physiological and health outcomes associated with elevated amino acid profiles is warranted.

  7. Utilisation of Giant African snail (Achatina fulica meal as protein source for laying hens

    Directory of Open Access Journals (Sweden)

    Siaka Seriba Diarra

    2015-05-01

    Full Text Available A 12-week experiment was carried out to investigate the effects of substituting Giant African snail meal for fish meal in laying hens diet. Four diets were formulated to contain snail meal as replacement for fish meal at 0 (control, 33, 67 and 100 %. A total of 120 Shaver Brown pullets aged 18 weeks were allocated to the dietary treatments in a randomised design. Each treatment consisted of three replicates and ten birds per replicate. Feed intake increased only for the 33% treatment as compared to the 67% replacement diet but did not differ from the other treatments. There were no significant treatment effects on egg performance parameters observed (egg production, egg weight, total egg mass, feed conversion ratio and percent shell. The overall feed cost of egg production reduced on the snail mealbased diets. The organoleptic evaluation of boiled eggs revealed no difference between the treatments. Based on these results it was concluded that total replacement of fish meal with cooked snail meat meal does not compromise laying performance or egg quality. The substitution is beneficial in terms of production cost reduction and the reduction of snails will have a beneficial impact especially where these snails are a serious agricultural pest. The manual collection and processing of snails can also become a source of rural income.

  8. Demodex-associated bacterial proteins induce neutrophil activation.

    LENUS (Irish Health Repository)

    2012-02-01

    Background: Patients with rosacea demonstrate a higher density of Demodex mites in their skin than controls. A bacterium isolated from a Demodex mite from a patient with papulopustular rosacea (PPR) was previously shown to provoke an immune response in patients with PPR or ocular rosacea thus suggesting a possible role for bacterial proteins in the etiology of this condition. Objectives: To examine the response of neutrophils to proteins derived from a bacterium isolated from a Demodex mite. Methods: Bacterial cells were lysed and proteins were partially purified by AKTA-FPLC. Isolated neutrophils were exposed to bacterial proteins and monitored for alterations in migration, degranulation and cytokine production. Results: Neutrophils exposed to proteins from Bacillus cells demonstrated increased levels of migration and elevated release of MMP-9, an enzyme known to degrade collagen and cathelicidin, an antimicrobial peptide. In addition neutrophils exposed to the bacterial proteins demonstrated elevated rates of Il-8 and TNF-alpha production. Conclusions: Proteins produced by a bacterium isolated from a Demodex mite have the ability to increase the migration, degranulation and cytokine production abilities of neutrophils. These results suggest that bacteria may play a role in the inflammatory erythema associated with rosacea.

  9. Bacterial spore germination and protein mobility.

    Science.gov (United States)

    Moir, Anne

    2003-10-01

    Fluorescence recovery after photobleaching (FRAP) of green fluorescent protein (GFP) has been used to report on protein mobility in single spores. Proteins found in dormant Bacillus spores are not mobile; however, mobility is restored when germination occurs and the core rehydrates. Spores of a cwlD mutant, in which the cortex is resistant to hydrolysis, are able to complete the earliest stages of germination in response to a specific germinant stimulus; in these circumstances, the protein in the spore remains immobile. Therefore, the earliest stages of spore germination, including loss of resistance to extreme heat and the complete release of the spore component dipicolinic acid, are achieved without the restoration of protein mobility.

  10. The structure of bacterial S-layer proteins.

    Science.gov (United States)

    Pavkov-Keller, Tea; Howorka, Stefan; Keller, Walter

    2011-01-01

    S-layers are self-assembled paracrystalline protein lattices that cover many bacteria and almost all archaea. As an important component of the bacterial cell envelope, S-layers can fulfill various biological functions and are usually the most abundantly expressed protein species in a cell. Here we review the structures of the best characterized S-layer proteins from Gram-positive and Gram-negative bacteria, as well as methods to determine their molecular architecture.

  11. Insights into bacterial protein glycosylation in human microbiota.

    Science.gov (United States)

    Zhu, Fan; Wu, Hui

    2016-01-01

    The study of human microbiota is an emerging research topic. The past efforts have mainly centered on studying the composition and genomic landscape of bacterial species within the targeted communities. The interaction between bacteria and hosts is the pivotal event in the initiation and progression of infectious diseases. There is a great need to identify and characterize the molecules that mediate the bacteria-host interaction. Bacterial surface exposed proteins play an important role in the bacteria- host interaction. Numerous surface proteins are glycosylated, and the glycosylation is crucial for their function in mediating the bacterial interaction with hosts. Here we present an overview of surface glycoproteins from bacteria that inhabit three major mucosal environments across human body: oral, gut and skin. We describe the important enzymes involved in the process of protein glycosylation, and discuss how the process impacts the bacteria-host interaction. Emerging molecular details underlying glycosylation of bacterial surface proteins may lead to new opportunities for designing anti-infective small molecules, and developing novel vaccines in order to treat or prevent bacterial infection.

  12. Studies on substitutional protein sources for fish meal in the diet of Japanese flounder; Hirame shiryo ni okeru miriyo shigen no riyo

    Energy Technology Data Exchange (ETDEWEB)

    Kikuchi, K.; Furuta, T.; Sakaguchi, I. [Central Research Institute of Electric Power Industry, Tokyo (Japan)

    1996-08-01

    Effectiveness of livestock industry wastes and vegetable protein added to fish meal in fish farming is tested by feeding the Japanese flounder. In the experiment, a part or the whole of the fish meal protein is replaced by the meat meal (MM), meat and bone meal (MBM), corngluten meal (CGM), or dried silkworm pupa meal (SPM), and fries of the Japanese flounder are fed on the new diets for eight weeks. On a diet containing 60% or less of MM, no change is detected in the fish in terms of increase in weight, protein efficiency ratio, and blood components, indicating that 60% at the highest of fish meal may be replaced by MM. In the case of MBM, it can occupy approximately 20%. As for CGM, the proper substitution rate is approximately 40%. Essential amino acids that the new diets may lack are added for an approximately 10% improvement on the result. The SPM substitution works up to 40%, when, however, the blood components are degraded. The proper substitution rate is therefore placed at approximately 20%. 38 refs., 2 figs., 17 tabs.

  13. Glycemia and insulinemia in healthy subjects after lactose-equivalent meals of milk and other food proteins

    DEFF Research Database (Denmark)

    Nilsson, Mikael; Stenberg, Marianne; Frid, Anders H

    2004-01-01

    for leucine, valine, lysine, and isoleucine. A correlation was also obtained between responses of insulin and GIP concentrations. Reconstituted milk powder and whey had substantially lower postprandial glucose areas under the curve (AUCs) than did the bread reference (-62% and -57%, respectively). Whey meal......BACKGROUND: Milk products deviate from other carbohydrate-containing foods in that they produce high insulin responses, despite their low GI. The insulinotropic mechanism of milk has not been elucidated. OBJECTIVE: The objective was to evaluate the effect of common dietary sources of animal...... or vegetable proteins on concentrations of postprandial blood glucose, insulin, amino acids, and incretin hormones [glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide 1] in healthy subjects. DESIGN: Twelve healthy volunteers were served test meals consisting of reconstituted milk...

  14. Salmon testes meal as a functional feed additive in fish meal and plant-protein based diets for rainbow trout(Oncorhynchus mykiss walbaum)and nile tilapia(Oreochromis niloticus L.) fry

    Science.gov (United States)

    We report that salmon testes meal (TM) produced from Alaskan seafood processing byproducts is a potential protein source for aquafeed formulations. A series of feeding trials was conducted using three different fish species; including Nile tilapia, rainbow trout, and white sturgeon at their early gr...

  15. Physicochemical and functional properties of rapeseed protein isolate: influence of antinutrient removal with acidified organic solvents from rapeseed meal.

    Science.gov (United States)

    Das Purkayastha, Manashi; Gogoi, Jyotchna; Kalita, Dipankar; Chattopadhyay, Pronobesh; Nakhuru, Khonamai Sewa; Goyary, Danswrang; Mahanta, Charu Lata

    2014-08-06

    The presence of antinutritional constituents in rapeseed protein products (RPI), such as polyphenols, phytates, allyl isothiocyanates, and glucosinolates, is a formidable constraint. The effect of antinutrient removal from rapeseed meal with an organic solvent mixture (methanol/acetone, 1:1 v/v, combined with an acid (hydrochloric, acetic, perchloric, trichloroacetic, phosphoric)) on the physicochemical and functional properties of RPI was investigated. The extraction resulted in a substantial reduction of antinutrients from RPI, especially polyphenols and phytates, with concomitant decreases in protein yield and solubility. Treatment harbored significant improvement in the degree of whiteness, which was highest in the perchloric acid case. Surface hydrophobicity and free sulfhydryl group of RPI changed considerably, with perchloric acid-treated samples showing higher values, whereas the disulfide content remarkably increased in trichloroacetic acid- and phosphoric acid-treated samples, signifying aggregation. Intrinsic emission fluorescence and FTIR spectra showed significant changes in proteins' tertiary and secondary conformations, and the changes were more pronounced in samples treated with higher concentrations of acids. No appreciable alteration appeared among the electrophoretic profiles of proteins from pristine meal and those treated with lower levels of acids. Interfacial surface properties of proteins were variably improved by the solvent extraction, whereas the converse was true for their extent of denaturation. The results suggest that the physicochemical and conformational properties of RPI are closely related to its functional properties.

  16. Effects of the Sequence of Isocaloric Meals with Different Protein Contents on Plasma Biochemical Indexes in Pigs.

    Directory of Open Access Journals (Sweden)

    Chunyan Xie

    Full Text Available Nutrient composition and pattern of food intake may play a significant role in weight gain. The aim of this study was to document the effects of a daily 3-meal pattern with isocaloric diets containing different dietary protein contents on growth performance and different plasma biochemical indexes including amino acid plasma concentration in castrated male pigs. Then, 21 DLY (Duroc×Landrace×Yorkshire pigs aged 60 days were assigned randomly into 3 groups: a control group (crude protein, CP 18.1%, a group receiving high then basal and then low CP meals (High-Low group and a group receiving low then basal and then high CP meal (Low-High group for 40 days with pigs being feed-restricted. On day 40, after 12 h fasting, blood samples were obtained for analysis. The results showed that the insulin/glucagon ratio was lower in the High-Low group (P<0.05 when compared with the control group. Compared with the control group, the average daily gain of pigs from the High-Low group increased by 14.10% (P = 0.046. Compared with the control group, serum gamma-glutamyl transferase (GGT decreased significantly (P<0.05 in both the High-Low and Low-High groups. Plasma concentrations of branched-chain amino acids (BCAA: valine, isoleucine and leucine increased in the Low-High group (P<0.05 when compared with the control group; and plasma methionine and serine decreased in both the two experimental groups (P<0.05. Compared with the High-Low group, all the BCAA increased significantly (P<0.05 in the Low-High group. These findings suggest that the sequence and quantity of alimentary protein intake affect the insulin/glucagon ratio, as well as amino acid concentrations including BCAA, methionine and serine. It is proposed that meal pattern with pigs receiving high then basal and then low CP meals daily may help to improve the weight gain of pigs.

  17. Monocyte chemotactic protein-1 gene polymorphism and spontaneous bacterial peritonitis

    Institute of Scientific and Technical Information of China (English)

    Levent; Filik

    2010-01-01

    I read with great interest the article by Gbele et al published in issue 44 of World J Gastroenterol 2009.The results of their study indicate that-2518 Monocyte chemotactic protein-1(MCP-1)genotype AA is a risk factor for spontaneous bacterial peritonitis in patients with alcoholic cirrhosis.However,there are some items that need to be discussed.

  18. Surface display of proteins by Gram-negative bacterial autotransporters

    Directory of Open Access Journals (Sweden)

    Mourez Michael

    2006-06-01

    Full Text Available Abstract Expressing proteins of interest as fusions to proteins of the bacterial envelope is a powerful technique with many biotechnological and medical applications. Autotransporters have recently emerged as a good tool for bacterial surface display. These proteins are composed of an N-terminal signal peptide, followed by a passenger domain and a translocator domain that mediates the outer membrane translocation of the passenger. The natural passenger domain of autotransporters can be replaced by heterologous proteins that become displayed at the bacterial surface by the translocator domain. The simplicity and versatility of this system has made it very attractive and it has been used to display functional enzymes, vaccine antigens as well as polypeptides libraries. The recent advances in the study of the translocation mechanism of autotransporters have raised several controversial issues with implications for their use as display systems. These issues include the requirement for the displayed polypeptides to remain in a translocation-competent state in the periplasm, the requirement for specific signal sequences and "autochaperone" domains, and the influence of the genetic background of the expression host strain. It is therefore important to better understand the mechanism of translocation of autotransporters in order to employ them to their full potential. This review will focus on the recent advances in the study of the translocation mechanism of autotransporters and describe practical considerations regarding their use for bacterial surface display.

  19. Determination of processed animal proteins, including meat and bone meal, in animal feed.

    Science.gov (United States)

    Gizzi, Giséile; von Holst, Christoph; Baeten, Vincent; Berben, Gilbert; van Raamsdonk, Leo

    2004-01-01

    An intercomparison study was conducted to determine the presence of processed animal proteins (PAPs), including meat and bone meal (MBM) from various species, in animal feed. The performances of different methods, such as microscopy, polymerase chain reaction (PCR), immunoassays, and a protocol based on iquid chromatography (LC), were compared. Laboratories were asked to analyze for PAPs from all terrestrial animals and fish (total PAPs); mammalian PAPs; ruminant PAPs; and porcine PAPs. They were free to use their method of choice. In addition, laboratories using microscopy were asked to determine the presence of PAPs from terrestrial animals, which is applicable only to microscopy. For total PAPs microscopy, LC and some immunoassays showed sufficient results at a concentration as low as 0.1% MBM in the feed. In contrast, PCR was not fit for purpose. In differentiating between MBM from terrestrial animals and fishmeal, microscopy detected 0.5% of terrestrial MBM in feed in the presence of 5% fishmeal, but was less successful when the concentration of MBM from terrestrial animals was 0.1%. The animal-specific determination of MBM from mammals or, more specifically from either ruminants or pigs, by PCR showed poor results, as indicated by a high number of false-positive and false-negative results. The only PCR method that scored quite well was applied by a member of the organizer team of the study. Immunoassays scored much better than PCR, showing sufficient sensitivity but some deficiency in terms of specificity. The results also demonstrated that the reliable determination of MBM from ruminants has not been resolved, especially for low concentrations of MBM (0.1%) in feed. Comparison of the results for mammalian MBM from all methods indicated that, for control purposes, the immunoassay method, especially when applied as dipsticks, could be used as a rapid screening method combined with microscopy to confirm the positive samples. However, implementation of such a

  20. Fermentation characteristics, chemical composition and fractionation of carbohydrates and crude protein of silage of elephant grass wilted or with addition of castor bean meal

    Directory of Open Access Journals (Sweden)

    Leandro Sampaio Oliveira Ribeiro

    2014-06-01

    Full Text Available The experiment was conducted to evaluate the concentrations of ammonia nitrogen, hydrogen potential, the losses of deriving the fermentative process, nutritional value, the fractioning of carbohydrates and protein the elephant grass silage wilted or not containing castor bean meal. The experimental design was completely randomized, with five treatments and with four replications: elephant grass wilted; elephant not wilted; elephant grass more castor bean meal (6%; elephant grass more castor bean meal (12% and elephant grass more castor bean meal (18%, the coproduct was added with base on natural matter. We adopted a specific mass of 600 kg/m3. The silage containing 18% castor bean meal showed higher (P0.05 among the silages with additives for fractions A+B1, B2 and C. For the protein fractioning, the fractions A and C decreased (P<0.05 with increase of the inclusion of castor bean meal, differently, of the fraction B1+B2 which increased. The castor bean stands out as a good additive in silage of elephant grass to reduce moisture and improve the fermentation characteristics of silages also was effective in increasing the protein value of silages, especially when using the dose 18%.

  1. Recombinant Expression Screening of P. aeruginosa Bacterial Inner Membrane Proteins

    Directory of Open Access Journals (Sweden)

    Jeffery Constance J

    2010-11-01

    Full Text Available Abstract Background Transmembrane proteins (TM proteins make up 25% of all proteins and play key roles in many diseases and normal physiological processes. However, much less is known about their structures and molecular mechanisms than for soluble proteins. Problems in expression, solubilization, purification, and crystallization cause bottlenecks in the characterization of TM proteins. This project addressed the need for improved methods for obtaining sufficient amounts of TM proteins for determining their structures and molecular mechanisms. Results Plasmid clones were obtained that encode eighty-seven transmembrane proteins with varying physical characteristics, for example, the number of predicted transmembrane helices, molecular weight, and grand average hydrophobicity (GRAVY. All the target proteins were from P. aeruginosa, a gram negative bacterial opportunistic pathogen that causes serious lung infections in people with cystic fibrosis. The relative expression levels of the transmembrane proteins were measured under several culture growth conditions. The use of E. coli strains, a T7 promoter, and a 6-histidine C-terminal affinity tag resulted in the expression of 61 out of 87 test proteins (70%. In this study, proteins with a higher grand average hydrophobicity and more transmembrane helices were expressed less well than less hydrophobic proteins with fewer transmembrane helices. Conclusions In this study, factors related to overall hydrophobicity and the number of predicted transmembrane helices correlated with the relative expression levels of the target proteins. Identifying physical characteristics that correlate with protein expression might aid in selecting the "low hanging fruit", or proteins that can be expressed to sufficient levels using an E. coli expression system. The use of other expression strategies or host species might be needed for sufficient levels of expression of transmembrane proteins with other physical

  2. Bacterial S-layer protein coupling to lipids

    DEFF Research Database (Denmark)

    Weygand, M.; Wetzer, B.; Pum, D.

    1999-01-01

    The coupling of bacterial surface (S)-layer proteins to lipid membranes is studied in molecular detail for proteins from Bacillus sphaericus CCM2177 and B. coagulans E38-66 recrystallized at dipalmitoylphosphatidylethanolamine (DPPE) monolayers on aqueous buffer. A comparison of the monolayer...... that the phosphatidylethanolamine headgroups must reorient toward the surface normal to accommodate such changes. In terms of the protein structure (which is as yet unknown in three dimensions), the electron density profile reveals a thickness I(z) approximate to 90 Angstrom of the recrystallized S-layer and shows water......-filled cavities near its center. The protein volume fraction reaches maxima of >60% in two horizontal sections of the S-layer, close to the lipid monolayer and close to the free subphase. In between it drops to similar to 20%. Four S-layer protein monomers are located within the unit cell of a square lattice...

  3. Protein-lipid interactions in the purple bacterial reaction centre.

    Science.gov (United States)

    Jones, Michael R; Fyfe, Paul K; Roszak, Aleksander W; Isaacs, Neil W; Cogdell, Richard J

    2002-10-11

    The purple bacterial reaction centre uses the energy of sunlight to power energy-requiring reactions such as the synthesis of ATP. During the last 20 years, a combination of X-ray crystallography, spectroscopy and mutagenesis has provided a detailed insight into the mechanism of light energy transduction in the bacterial reaction centre. In recent years, structural techniques including X-ray crystallography and neutron scattering have also been used to examine the environment of the reaction centre. This mini-review focuses on recent studies of the surface of the reaction centre, and briefly discusses the importance of the specific protein-lipid interactions that have been resolved for integral membrane proteins.

  4. Inactivation of indispensable bacterial proteins by early proteins of bacteriophages: implication in antibacterial drug discovery.

    Science.gov (United States)

    Sau, S; Chattoraj, P; Ganguly, T; Chanda, P K; Mandal, N C

    2008-06-01

    Bacteriophages utilize host bacterial cellular machineries for their own reproduction and completion of life cycles. The early proteins that phage synthesize immediately after the entry of their genomes into bacterial cells participate in inhibiting host macromolecular biosynthesis, initiating phage-specific replication and synthesizing late proteins. Inhibition of synthesis of host macromolecules that eventually leads to cell death is generally performed by the physical and/or chemical modification of indispensable host proteins by early proteins. Interestingly, most modified bacterial proteins were shown to take part actively in phage-specific transcription and replication. Research on phages in last nine decades has demonstrated such lethal early proteins that interact with or chemically modify indispensable host proteins. Among the host proteins inhibited by lethal phage proteins, several are not inhibited by any chemical inhibitor available today. Under the context of widespread dissemination of antibiotic-resistant strains of pathogenic bacteria in recent years, the information of lethal phage proteins and cognate host proteins could be extremely invaluable as they may lead to the identification of novel antibacterial compounds. In this review, we summarize the current knowledge about some early phage proteins, their cognate host proteins and their mechanism of action and also describe how the above interacting proteins had been exploited in antibacterial drug discovery.

  5. The anabolic response to a meal containing different amounts of protein is not limited by the maximal stimulation of protein synthesis in healthy young adults.

    Science.gov (United States)

    Kim, Il-Young; Schutzler, Scott; Schrader, Amy; Spencer, Horace J; Azhar, Gohar; Ferrando, Arny A; Wolfe, Robert R

    2016-01-01

    We have determined whole body protein kinetics, i.e., protein synthesis (PS), breakdown (PB), and net balance (NB) in human subjects in the fasted state and following ingestion of ~40 g [moderate protein (MP)], which has been reported to maximize the protein synthetic response or ~70 g [higher protein (HP)] protein, more representative of the amount of protein in the dinner of an average American diet. Twenty-three healthy young adults who had performed prior resistance exercise (X-MP or X-HP) or time-matched resting (R-MP or R-HP) were studied during a primed continuous infusion of l-[(2)H5]phenylalanine and l-[(2)H2]tyrosine. Subjects were randomly assigned into an exercise (X, n = 12) or resting (R, n = 11) group, and each group was studied at the two levels of dietary protein intake in random order. PS, PB, and NB were expressed as increases above the basal, fasting values (mg·kg lean body mass(-1)·min(-1)). Exercise did not significantly affect protein kinetics and blood chemistry. Feeding resulted in positive NB at both levels of protein intake: NB was greater in response to the meal containing HP vs. MP (P protein synthesis (for all, P protein balance improves with greater protein intake above that previously suggested to maximally stimulating muscle protein synthesis because of a simultaneous reduction in protein breakdown.

  6. Nutritional evaluation of the germ meal and its protein isolate obtained from the carob seed (Ceratonia siliqua) in the rat.

    Science.gov (United States)

    Drouliscos, N J; Malefaki, V

    1980-01-01

    1. Evaluation of the germ meal (CGM) of carob seed (Ceratonia siliqua) and its protein isolate was carried out with weanling rats. Comparisons were made with casein, soya-bean meal, whole defatted egg and a soya-bean protein isolate (Promine-D) as protein sources. The growth-promoting effects and certain biological indices were evaluated using the protein efficiency ratio (PER), biological value (BV) and net protein utilization (NPU) bioassay procedures. 2. The unsupplemented CGM had a PER of 1.66 +/- 0.09 and an NPU of 0.58 +/- 0.013. Addition of DL-methionine at 4, 8 and 12 g/kg diet resulted in a PER of 1.95 +/- 0.11, 2.01 +/- 0.11 and 1.90 +/- 0.11 respectively. The corresponding BV values were 0.80 +/- 0.003, 0.78 +/- 0.015 and 0.74 +/- 0.011, and those for NPU 0.69 +/- 0.013, 0.66 +/- 0.026 and 0.63 +/- 0.020 respectively. The addition of amino acids improved the PER (2.24--2.59), BV (0.78--0.79) and NPU (0.71--0.73) values. 3. The BV and NPU assays for the unsupplemented carob germ isolate were low (BV 0.36 +/- 0.016, NPU 0.35 +/- 0.015). Supplementation with amino acids resulted in a positive increase with values of 0.66 +/- 0.013 and 0.64 +/- 0.013 for BV and NPU respectively.

  7. Chemiluminescence enzyme immunoassay using ProteinA-bacterial magnetite complex

    Science.gov (United States)

    Matsunaga, Tadashi; Sato, Rika; Kamiya, Shinji; Tanaka, Tsuyosi; Takeyama, Haruko

    1999-04-01

    Bacterial magnetic particles (BMPs) which have ProteinA expressed on their surface were constructed using magA which is a key gene in BMP biosynthesis in the magnetic bacterium Magnetospirillum sp. AMB-1. Homogenous chemiluminescence enzyme immunoassay using antibody bound ProteinA-BMP complexes was developed for detection of human IgG. A good correlation between the luminescence yield and the concentration of human IgG was obtained in the range of 1-10 3 ng/ml.

  8. Easy Meal

    Science.gov (United States)

    1978-01-01

    The woman pictured below is sitting down to a nutritious, easily-prepared meal similar to those consumed by Apollo astronauts. The appetizing dishes shown were created simply by adding water to the contents of a Mountain House* Easy Meal package of freeze dried food. The Easy Meal line is produced by Oregon Freeze Dry Foods, Inc., Albany, Oreaon, a pioneer in freeze drying technology and a company long associated with NASA in developing suitable preparations for use on manned spacecraft. Designed to provide nutritionally balanced, attractive hot meals for senior adults, Easy Meal is an offshoot of a 1975-77 demonstration project managed by Johnson Space Center and called Meal System for the Elderly. The project sought ways to help the estimated 3.5 million elderly Americans who are unable to take advantage of existing meal programs. Such services are provided by federal, state and local agencies, but they are not available to many who live in rural areas, or others who are handicapped, temporarily ill or homebound for other reasons. Oregon Freeze Dry Foods was a participant in that multi-agency cooperative project. With its Easy Meal assortment of convenience foods pictured above left, the company is making commercially available meal packages similar to those distributed in the Meal System for the Elderly program. In the freeze drying process, water is extracted from freshly-cooked foods by dehydration at very low temperatures, as low as 50 I degrees below zero. Flavor is locked in by packaging the dried food in pouches which block out moisture and oxygen, the principal causes of food deterioration; thus the food can be stored for long periods without refrigeration. Meals are reconstituted by adding hot or cold water, depending on the type of food, and they are table ready in five to 10 minutes. Oregon Freeze Dry Foods offers five different meal packages and plans to expand the line.

  9. The Impact of Rendered Protein Meal Oxidation Level on Shelf-Life, Sensory Characteristics, and Acceptability in Extruded Pet Food.

    Science.gov (United States)

    Chanadang, Sirichat; Koppel, Kadri; Aldrich, Greg

    2016-07-28

    Pet foods are expected to have a shelf-life for 12 months or more. Sensory analysis can be used to determine changes in products and to estimate products' shelf-life. The objectives of this study were to (1) investigate how increasing levels of oxidation in rendered protein meals used to produce extruded pet food affected the sensory properties and (2) determine the effect of shelf-life on pet owners' acceptability of extruded pet food diet formulated without the use of preservative. Pet food diets contained beef meat bone meal (BMBM) and chicken byproduct meal (CBPM) in which the oxidation was retarded with ethoxyquin, mixed tocopherols, or none at all, and then extruded into dry pet foods. These samples represented low, medium, and high oxidation levels, respectively. Samples were stored for 0, 3, 6, 9, and 12 months at ambient temperature. Each time point, samples were evaluated by six highly trained descriptive panelists for sensory attributes related to oxidation. Samples without preservatives were chosen for the acceptability test, since the differences in sensory characteristics over storage time were more distinguishable in those samples. Pet owners evaluated samples for aroma, appearance and overall liking. Descriptive sensory analysis detected significant changes in oxidized-related sensory characteristics over storage time. However, the differences for CBPM samples were more pronounced and directional. The consumer study showed no differences in pet owners' acceptability for BMBM samples. However, the noticeable increase in aroma characteristics (rancid aroma 0.33-4.21) in CBPM samples over storage time did have a negative effect on consumer's liking (overall liking 5.52-4.95).

  10. A versatile nano display platform from bacterial spore coat proteins.

    Science.gov (United States)

    Wu, I-Lin; Narayan, Kedar; Castaing, Jean-Philippe; Tian, Fang; Subramaniam, Sriram; Ramamurthi, Kumaran S

    2015-04-09

    Dormant bacterial spores are encased in a thick protein shell, the 'coat', which contains ∼70 different proteins. The coat protects the spore from environmental insults, and is among the most durable static structures in biology. Owing to extensive cross-linking among coat proteins, this structure has been recalcitrant to detailed biochemical analysis, so molecular details of how it assembles are largely unknown. Here, we reconstitute the basement layer of the coat atop spherical membranes supported by silica beads to create artificial spore-like particles. We report that these synthetic spore husk-encased lipid bilayers (SSHELs) assemble and polymerize into a static structure, mimicking in vivo basement layer assembly during sporulation in Bacillus subtilis. In addition, we demonstrate that SSHELs may be easily covalently modified with small molecules and proteins. We propose that SSHELs may be versatile display platforms for drugs and vaccines in clinical settings, or for enzymes that neutralize pollutants for environmental remediation.

  11. Ileal digestibility of amino acids in novel organic protein feedstuffs for pigs: Black soldier fly larvae meal(Hermetia illucens)

    OpenAIRE

    Kortelainen, Tiina; Siljander-Rasi, Hilkka; Tuori, Mikko; Partanen, Kirsi

    2014-01-01

    Abstract The objective of this study was to determine the standardised ileal digestibility (SID) of amino acids in organically produced black soldier fly larvae (Hermeti illucens) meal in growing piglets. The use of Hermetia meal in pig feeding is not allowed for the time being, but feed legislation in the EU concerning the use of Hermetia meal for pigs is in progress. Two batches of Hermetia meal arrived from Switzerland (FiBL Research Institute of Organic Agriculture). In batch 1, fa...

  12. C-REACTIVE PROTEIN IN BACTERIAL MENINGITIS: DOSE IT HELP TO DIFFERENTIATE BACTERIAL FROM VIRAL MENINGITIS?

    Directory of Open Access Journals (Sweden)

    AR EMAMI NAEINI

    2001-03-01

    Full Text Available Introduction. Central nervous system infections are among the most serious conditions in of medical practice. C-reactive Protein has recently been evaluated in terms of its ability to diffeccentiate bacterial from nonbacterial central nervous system inflammations.
    Methods. We studied the frequency of positive CRP in 61 patients who had signs of meningitis. All the specimens referred to one laboratory and were examined by Slide method.
    Results. Positive CRP was found in 97.6 percent of those who were finally diagnosed as bacterial meningitis. The frequency of CRP for other types of meningitis was 16.6 percent (P < 0.05.
    Discussion. In the absence of infection, CSF is free of CRP. Positive CRP may help to the differentiate the different types of meningitis.

  13. Packaging protein drugs as bacterial inclusion bodies for therapeutic applications

    Directory of Open Access Journals (Sweden)

    Villaverde Antonio

    2012-06-01

    Full Text Available Abstract A growing number of insights on the biology of bacterial inclusion bodies (IBs have revealed intriguing utilities of these protein particles. Since they combine mechanical stability and protein functionality, IBs have been already exploited in biocatalysis and explored for bottom-up topographical modification in tissue engineering. Being fully biocompatible and with tuneable bio-physical properties, IBs are currently emerging as agents for protein delivery into mammalian cells in protein-replacement cell therapies. So far, IBs formed by chaperones (heat shock protein 70, Hsp70, enzymes (catalase and dihydrofolate reductase, grow factors (leukemia inhibitory factor, LIF and structural proteins (the cytoskeleton keratin 14 have been shown to rescue exposed cells from a spectrum of stresses and restore cell functions in absence of cytotoxicity. The natural penetrability of IBs into mammalian cells (reaching both cytoplasm and nucleus empowers them as an unexpected platform for the controlled delivery of essentially any therapeutic polypeptide. Production of protein drugs by biopharma has been traditionally challenged by IB formation. However, a time might have arrived in which recombinant bacteria are to be engineered for the controlled packaging of therapeutic proteins as nanoparticulate materials (nanopills, for their extra- or intra-cellular release in medicine and cosmetics.

  14. N-linked protein glycosylation in a bacterial system.

    Science.gov (United States)

    Nothaft, Harald; Liu, Xin; McNally, David J; Szymanski, Christine M

    2010-01-01

    N-Linked protein glycosylation is conserved throughout the three domains of life and influences protein function, stability, and protein complex formation. N-Linked glycosylation is an essential process in Eukaryotes; however, although N-glycosylation affects multiple cellular processes in Archaea and Bacteria, it is not needed for cell survival. Methods for the analyses of N-glycosylation in eukaryotes are well established, but comparable techniques for the analyses of the pathways in Bacteria and Archaea are needed. In this chapter we describe new methods for the detection and analyses of N-linked, and the recently discovered free oligosaccharides (fOS), from whole cell lysates of Campylobacter jejuni using non-specific pronase E digestion and permethylation followed by mass spectrometry. We also describe the expression and immunodetection of the model N-glycoprotein, AcrA, fused to a hexa-histidine tag to follow protein glycosylation in C. jejuni. This chapter concludes with the recent demonstration that high-resolution magic angle spinning NMR of intact bacterial cells provides a rapid, non-invasive method for analyzing fOS in C. jejuni in vivo. This combination of techniques provides a powerful tool for the exploration, quantification, and structural analyses of N-linked and free oligosaccharides in the bacterial system.

  15. A Study on the Meat and Bone Meal or Poultry By-product Meal as Protein Substitutes of Fishmeal in Concentrated Diets for Paralichthys olivaceus

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A study was conducted to evaluate the effects of meat and bone meal (MBM) and poultry by-product meal (PBM) as the replacement of fishmeal in the diets on the growth performance, survival and apparent digestibility coefficient (ADC) of Japanese flounder (Paralichthys olivaceus). The experimental diets included 0%, 20%, 40%, 60% and 80% MBM or PBM replacement of total fishmeal respectively. All diets were iso-nitrogenous and isocaloric. The results showed that there are no significant differences (P>0.05) in growth performance among the treatments fed with 0%-60% MBM replacement of fishmeal, while the percent weight gain (WG,%), body length gain (BLG, %) and ADC significantly decrease when fishmeal is replaced by 80% MBM. The result showed also that there are no significant differences (P>0.05) in growth performance and ADC among all treatments fed with the diets with 0%-80% replacements of fishmeal with PBM.

  16. A study on the meat and bone meal or poultry by-product meal as protein substitutes of fishmeal in concentrated diets for Paralichthys olivaceus

    Science.gov (United States)

    Zhu, Wei; Mai, Kangsen; Zhang, Baigang; Hu, Yangjiang; Yu, Yu

    2006-01-01

    A study was conducted to evaluate the effects of meat and bone meal (MBM) and poultry by-product meal (PBM) as the replacement of fishmeal in the diets on the growth performance, survival and apparent digestibility coefficient (ADC) of Japanese flounder ( Paralichthys olivaceus). The experimental diets included 0%, 20%, 40%, 60% and 80% MBM or PBM replacement of total fishmeal respectively. All diets were iso-nitrogenous and isocaloric. The results showed that there are no significant differences ( P>0.05) in growth performance among the treatments fed with 0% 60% MBM replacement of fishmeal, while the percent weight gain (WG, %), body length gain (BLG, %) and ADC significantly decrease when fishmeal is replaced by 80% MBM. The result showed also that there are no significant differences ( P>0.05) in growth performance and ADC among all treatments fed with the diets with 0% 80% replacements of fishmeal with PBM.

  17. Protein export through the bacterial flagellar type III export pathway.

    Science.gov (United States)

    Minamino, Tohru

    2014-08-01

    For construction of the bacterial flagellum, which is responsible for bacterial motility, the flagellar type III export apparatus utilizes both ATP and proton motive force across the cytoplasmic membrane and exports flagellar proteins from the cytoplasm to the distal end of the nascent structure. The export apparatus consists of a membrane-embedded export gate made of FlhA, FlhB, FliO, FliP, FliQ, and FliR and a water-soluble ATPase ring complex consisting of FliH, FliI, and FliJ. FlgN, FliS, and FliT act as substrate-specific chaperones that do not only protect their cognate substrates from degradation and aggregation in the cytoplasm but also efficiently transfer the substrates to the export apparatus. The ATPase ring complex facilitates the initial entry of the substrates into the narrow pore of the export gate. The export gate by itself is a proton-protein antiporter that uses the two components of proton motive force, the electric potential difference and the proton concentration difference, for different steps of the export process. A specific interaction of FlhA with FliJ located in the center of the ATPase ring complex allows the export gate to efficiently use proton motive force to drive protein export. The ATPase ring complex couples ATP binding and hydrolysis to its assembly-disassembly cycle for rapid and efficient protein export cycle. This article is part of a Special Issue entitled: Protein trafficking and secretion in bacteria. Guest Editors: Anastassios Economou and Ross Dalbey.

  18. Evaluation of plant and animal protein sources as partial or total replacement of fish meal in diets for juvenile Nile tilapia

    Science.gov (United States)

    A feeding trial was conducted in a closed system with Nile tilapia (Oreochromis niloticus) juveniles (mean weight, 2.84 g) to examine the effects of total replacement of fish meal (FM), with and without supplementation of DL-methionine (Met) and L-lysine (Lys), by plant protein sources. Fish were f...

  19. Comparison of adhesive properties of water- and phosphate-buffer-washed cottonseed meals with cottonseed protein isolate on maple and poplar veneers

    Science.gov (United States)

    Water- and phosphate buffer (35 mM Na2HPO4/NaH2PO4, pH 7.5)-washed cottonseed meals (abbreviated as WCM and BCM, respectively) could be low-cost and environmentally friendly protein-based adhesives as their preparation does not involve corrosive alkali and acid solutions that are needed for cottonse...

  20. Standardized ileal digestibility of proteins and amino acids in sesame expeller and soya bean meal in weaning piglets.

    Science.gov (United States)

    Aguilera, A; Reis de Souza, T C; Mariscal-Landín, G; Escobar, K; Montaño, S; Bernal, M G

    2015-08-01

    Apparent ileal digestibility (AID) of diets containing sesame expeller (SE) and soya bean meal (SBM) was determined using 15 piglets (Genetiporc(®)), weaned at 17 ± 0.4 days with average body weight of 6.4 ± 0.7 kg (Fertilis 20 × G Performance, Genetiporc(®), PIC México, Querétaro, México). Piglets were randomly assigned to three treatments: (i) a reference diet with casein as the sole protein source; (ii) a mixed diet of casein-SE; and (iii) a mixed diet of casein-SBM. The chemical composition of SE and SBM was determined, and AID and standardized ileal digestibility (SID) of crude protein (CP) and amino acids (AAs) were determined for each protein source. SE contained greater quantities of ether extract, neutral detergent fibre, phytic acid, methionine and arginine than SBM. Lysine and proline contents and trypsin inhibitor activity were higher in SBM than in SE. The AID and SID of CP and AA (except for lysine and proline) were similar in SE and SBM. The AID of lysine and proline was higher in SBM than in SE (p < 0.05), and the SID of proline was higher in SE than in SBM (p < 0.05). These findings indicate that SE is an appropriate alternative protein source for early weaned pigs.

  1. Protein chlorination in neutrophil phagosomes and correlation with bacterial killing.

    Science.gov (United States)

    Green, Jessie N; Kettle, Anthony J; Winterbourn, Christine C

    2014-12-01

    Neutrophils ingest and kill bacteria within phagocytic vacuoles. We investigated where they produce hypochlorous acid (HOCl) following phagocytosis by measuring conversion of protein tyrosine residues to 3-chlorotyrosine. We also examined how varying chloride availability affects the relationship between HOCl formation in the phagosome and bacterial killing. Phagosomal proteins, isolated following ingestion of opsonized magnetic beads, contained 11.4 Cl-Tyr per thousand tyrosine residues. This was 12 times higher than the level in proteins from the rest of the neutrophil and ~6 times higher than previously recorded for protein from ingested bacteria. These results indicate that HOCl production is largely localized to the phagosomes and a substantial proportion reacts with phagosomal protein before reaching the microbe. This will in part detoxify the oxidant but should also form chloramines which could contribute to the killing mechanism. Neutrophils were either suspended in chloride-free gluconate buffer or pretreated with formyl-Met-Leu-Phe, a procedure that has been reported to deplete intracellular chloride. These treatments, alone or in combination, decreased both chlorination in phagosomes and killing of Staphylococcus aureus by up to 50%. There was a strong positive correlation between the two effects. Killing was predominantly oxidant and myeloperoxidase dependent (88% inhibition by diphenylene iodonium and 78% by azide). These results imply that lowering the chloride concentration limits HOCl production and oxidative killing. They support a role for HOCl generation, rather than an alternative myeloperoxidase activity, in the killing process.

  2. Bacterial delivery of TALEN proteins for human genome editing.

    Directory of Open Access Journals (Sweden)

    Jingyue Jia

    Full Text Available Transcription Activator-Like Effector Nucleases (TALENs are a novel class of sequence-specific nucleases that have recently gained prominence for its ease of production and high efficiency in genome editing. A TALEN pair recognizes specific DNA sequences and introduce double-strand break in the target site, triggering non-homologous end joining and homologous recombination. Current methods of TALEN delivery involves introduction of foreign genetic materials, such as plasmid DNA or mRNA, through transfection. Here, we show an alternative way of TALEN delivery, bacterial type III secretion system (T3SS mediated direct injection of the TALEN proteins into human cells. Bacterially injected TALEN was shown to efficiently target host cell nucleus where it persists for almost 12 hours. Using a pair of TALENs targeting venus gene, such injected nuclear TALENs were shown functional in introducing DNA mutation in the target site. Interestingly, S-phase cells seem to show greater sensitivity to the TALEN mediated target gene modification. Accordingly, efficiency of such genome editing can easily be manipulated by the infection dose, number of repeated infections as well as enrichment of S phase cells. This work further extends the utility of T3SS in the delivery of functional proteins into mammalian cells to alter their characters for biomedical applications.

  3. Bacterial delivery of TALEN proteins for human genome editing.

    Science.gov (United States)

    Jia, Jingyue; Jin, Yongxin; Bian, Ting; Wu, Donghai; Yang, Lijun; Terada, Naohiro; Wu, Weihui; Jin, Shouguang

    2014-01-01

    Transcription Activator-Like Effector Nucleases (TALENs) are a novel class of sequence-specific nucleases that have recently gained prominence for its ease of production and high efficiency in genome editing. A TALEN pair recognizes specific DNA sequences and introduce double-strand break in the target site, triggering non-homologous end joining and homologous recombination. Current methods of TALEN delivery involves introduction of foreign genetic materials, such as plasmid DNA or mRNA, through transfection. Here, we show an alternative way of TALEN delivery, bacterial type III secretion system (T3SS) mediated direct injection of the TALEN proteins into human cells. Bacterially injected TALEN was shown to efficiently target host cell nucleus where it persists for almost 12 hours. Using a pair of TALENs targeting venus gene, such injected nuclear TALENs were shown functional in introducing DNA mutation in the target site. Interestingly, S-phase cells seem to show greater sensitivity to the TALEN mediated target gene modification. Accordingly, efficiency of such genome editing can easily be manipulated by the infection dose, number of repeated infections as well as enrichment of S phase cells. This work further extends the utility of T3SS in the delivery of functional proteins into mammalian cells to alter their characters for biomedical applications.

  4. Holo- And Apo- Structures of Bacterial Periplasmic Heme Binding Proteins

    Energy Technology Data Exchange (ETDEWEB)

    Ho, W.W.; Li, H.; Eakanunkul, S.; Tong, Y.; Wilks, A.; Guo, M.; Poulos, T.L.

    2009-06-01

    An essential component of heme transport in Gram-negative bacterial pathogens is the periplasmic protein that shuttles heme between outer and inner membranes. We have solved the first crystal structures of two such proteins, ShuT from Shigella dysenteriae and PhuT from Pseudomonas aeruginosa. Both share a common architecture typical of Class III periplasmic binding proteins. The heme binds in a narrow cleft between the N- and C-terminal binding domains and is coordinated by a Tyr residue. A comparison of the heme-free (apo) and -bound (holo) structures indicates little change in structure other than minor alterations in the heme pocket and movement of the Tyr heme ligand from an 'in' position where it can coordinate the heme iron to an 'out' orientation where it points away from the heme pocket. The detailed architecture of the heme pocket is quite different in ShuT and PhuT. Although Arg{sup 228} in PhuT H-bonds with a heme propionate, in ShuT a peptide loop partially takes up the space occupied by Arg{sup 228}, and there is no Lys or Arg H-bonding with the heme propionates. A comparison of PhuT/ShuT with the vitamin B{sub 12}-binding protein BtuF and the hydroxamic-type siderophore-binding protein FhuD, the only two other structurally characterized Class III periplasmic binding proteins, demonstrates that PhuT/ShuT more closely resembles BtuF, which reflects the closer similarity in ligands, heme and B{sub 12}, compared with ligands for FhuD, a peptide siderophore.

  5. Defining meal requirements for protein to optimize metabolic roles of amino acids

    Science.gov (United States)

    Dietary protein provides essential amino acids (EAAs) for the synthesis of new proteins plus an array of other metabolic functions; many of these functions are sensitive to postprandial plasma and intracellular amino acid concentrations. Recent research has focused on amino acids as metabolic signal...

  6. Exploring the anticancer potential of the bacterial protein azurin

    Directory of Open Access Journals (Sweden)

    Ananda M Chakrabarty

    2016-08-01

    Full Text Available Bacterial proteins and their derivative peptides have emerged as promising anticancer agents. Nowadays they represent a valuable set of candidate drugs with different origins and modes of action. Among these, monomeric cupredoxins, which are metalloproteins involved in the electron transport chain of prokaryotes, have been shown to possess potent anticancer activities. In particular, much attention has been focused on azurin produced by the pathogenic bacterium Pseudomonas aeruginosa. More recently, several in vitro and in vivo studies have reported the multi-targeting anticancer properties of azurin. Moreover, p28, a peptide derived from azurin, has completed two phase I clinical trials in cancer patients with promising results. In this updated review, we examine the current knowledge regarding azurin’s modes of action as an anticancer therapeutic protein. We also review the clinical trial results of p28 emphasizing findings that make it suited (alone or in combination as a therapeutic agent for cancer treatment. Finally we discuss and address the challenges of using the human microbiome to discover novel and unique therapeutic cupredoxin-like proteins.

  7. Targeting the Bacterial Division Protein FtsZ.

    Science.gov (United States)

    Hurley, Katherine A; Santos, Thiago M A; Nepomuceno, Gabriella M; Huynh, Valerie; Shaw, Jared T; Weibel, Douglas B

    2016-08-11

    Similar to its eukaryotic counterpart, the prokaryotic cytoskeleton is essential for the structural and mechanical properties of bacterial cells. The essential protein FtsZ is a central player in the cytoskeletal family, forms a cytokinetic ring at mid-cell, and recruits the division machinery to orchestrate cell division. Cells depleted of or lacking functional FtsZ do not divide and grow into long filaments that eventually lyse. FtsZ has been studied extensively as a target for antibacterial development. In this Perspective, we review the structural and biochemical properties of FtsZ, its role in cell biochemistry and physiology, the different mechanisms of inhibiting FtsZ, small molecule antagonists (including some misconceptions about mechanisms of action), and their discovery strategies. This collective information will inform chemists on different aspects of FtsZ that can be (and have been) used to develop successful strategies for devising new families of cell division inhibitors.

  8. Investigation of antibacterial mechanism and identification of bacterial protein targets mediated by antibacterial medicinal plant extracts.

    Science.gov (United States)

    Yong, Ann-Li; Ooh, Keng-Fei; Ong, Hean-Chooi; Chai, Tsun-Thai; Wong, Fai-Chu

    2015-11-01

    In this paper, we investigated the antibacterial mechanism and potential therapeutic targets of three antibacterial medicinal plants. Upon treatment with the plant extracts, bacterial proteins were extracted and resolved using denaturing gel electrophoresis. Differentially-expressed bacterial proteins were excised from the gels and subjected to sequence analysis by MALDI TOF-TOF mass spectrometry. From our study, seven differentially expressed bacterial proteins (triacylglycerol lipase, N-acetylmuramoyl-L-alanine amidase, flagellin, outer membrane protein A, stringent starvation protein A, 30S ribosomal protein s1 and 60 kDa chaperonin) were identified. Additionally, scanning electron microscope study indicated morphological damages induced on bacterial cell surfaces. To the best of our knowledge, this represents the first time these bacterial proteins are being reported, following treatments with the antibacterial plant extracts. Further studies in this direction could lead to the detailed understanding of their inhibition mechanism and discovery of target-specific antibacterial agents.

  9. Guangzhou Chemical Industry%Study on Extraction Conditions of Isolated Soybean Protein in Microbial Fermentation Soybean Meal

    Institute of Scientific and Technical Information of China (English)

    孙楠; 杜娜; 王霆

    2016-01-01

    采用碱提酸沉法对微生物发酵法制备的豆粕中提取大豆分离蛋白,并用凯氏定氮法测算大豆分离蛋白含量。研究碱提温度、液固比和碱提pH值及酸沉温度、时间和pH值对大豆分离蛋白提取率的影响。结果表明碱提的最佳工艺条件为:温度50℃、时间50 min、液固比10:1、 pH=9.0。酸沉的工艺参数为:温度45℃、时间40 min、 pH=4.5。所得大豆分离蛋白最高提取率为79.29%。%Alkaline extractionandacid precipitation were used to extract isolated protein from soybean meal produced by microbial fermentation. The content of isolated protein was calculated by kjeldahl method. Meanwhile, the extraction conditions of the isolated protein were studied. The optimum conditions of alkaline extractions were as follow: the temperature of extraction was 50℃, extracting time was 50 min, the ratio of liquidand solid was 10:1and pH was 9. 0. The optimum conditions of acid depositions were as follows:the temperature was 45 ℃,acid deposition time was 40 minand pH was 4. 5. The highest extraction yield of isolated protein was 79. 29%.

  10. Hearth bread characteristics: Effect of protein quality, protein content, whole meal flour, DATEM, proving time, and their interactions

    NARCIS (Netherlands)

    Aamodt, A.; Magnus, E.M.; Færgestad, E.M.

    2005-01-01

    The effects of protein quality, protein content, ingredients, and baking process of flour blends on hearth loaves were studied. The flour blends varied in protein composition and content. Flours of strong protein quality produced hearth loaves with larger loaf volume, larger bread slice area, and hi

  11. Growth performance and metabolic efficiency in Nile tilapia (Oreochromis niloticus L.) fed on a diet containing Jatropha platyphylla kernel meal as a protein source.

    Science.gov (United States)

    Kumar, V; Akinleye, A O; Makkar, H P S; Angulo-Escalante, M A; Becker, K

    2012-02-01

    Jatropha platyphylla is available on the pacific coast from Sinaloa to Michoacán including the Nayarit and Jalisco states in Mexico. The seeds of J. platyphylla are rich in oil and protein, and the kernel meal (JPKM) prepared after oil extraction contains 70-75% crude protein (CP). Contents of essential amino acids (except lysine) are higher in JPKM than in soybean meal (SBM). Phorbol-esters, the main toxin present in most Jatropha species is absent in J. platyphylla. Heat-treated JPKM (H-JPKM) was evaluated as a protein supplement in tilapia feed and compared with that of SBM and fish meal (FM). Nile tilapia (Oreochromis niloticus L.) fingerlings (15 fish; av. body mass 13.9 ± 0.17 g) were randomly distributed in three groups with five replicates each. A 12-week experiment was conducted in a respirometer system to evaluate the growth performance, nutrient utilization and energy budget. Nile tilapia fingerlings were fed three iso-nitrogenous diets (36% CP): Control containing FM, and Jatropha and Soybean diets in which 62.5% of FM protein was replaced by H-JPKM and SBM respectively. The growth performance, feed conversion ratio, protein efficiency ratio, apparent lipid conversion and energy retention did not differ significantly among the three groups. Higher protein productive value was observed in plant protein fed groups. Average metabolic rate, energy expenditure per g protein fed and retained in the body did not differ significantly among the three groups. Conclusively, Nile tilapia fed plant protein (heated JPKM and SBM) and FM protein-based diets exhibited equal average metabolic rate which indicate that JPKM can be used as a protein source in aqua feed.

  12. Effects of replacing rapeseed meal with fava bean at 2 concentrate crude protein levels on feed intake, nutrient digestion, and milk production in cows fed grass silage-based diets.

    Science.gov (United States)

    Puhakka, L; Jaakkola, S; Simpura, I; Kokkonen, T; Vanhatalo, A

    2016-10-01

    The objective of this study was to evaluate the production and physiological responses of dairy cows to the substitution of fava bean for rapeseed meal at 2 protein supplementation levels in grass silage-based diets. We used 6 primiparous and 6 multiparous Finnish Ayrshire cows in a cyclic changeover trial with a 2×3 factorial arrangement of treatments. The experimental diets consisted of formic acid-treated timothy-meadow fescue silage and 3 isonitrogenous concentrates containing either rapeseed meal, fava bean, or a 1:1 mixture of rapeseed meal and fava bean at low and high inclusion rates, resulting in concentrate crude protein (CP) levels of 15.4 and 19.0% in dry matter. Silage dry matter intake decreased linearly when rapeseed meal was replaced with fava bean, the negative effect being more distinct at the high CP level than the low (-2.3 vs. -0.9kg/d, respectively). Similarly, milk and milk protein yields decreased linearly with fava bean, the change tending to be greater at the high CP level than the low. Yield of milk fat was lower for fava bean compared with rapeseed meal, the difference showing no interaction with CP level. Especially at the high CP level, milk urea concentration was higher with fava bean compared with rapeseed meal indicating better utilization of protein from the rapeseed meal. The apparent total-tract organic matter digestibility did not differ between treatments at the low CP level, but digestibility was higher for fava bean than for rapeseed meal at the high CP level. Plasma concentrations of essential amino acids, including methionine and lysine, were lower for fava bean than for rapeseed meal. Compared with rapeseed meal, the use of fava bean in dairy cow diets as the sole protein supplement decreased silage intake and milk production in highly digestible formic acid-treated grass silage-based diets.

  13. Ribosome reinitiation at leader peptides increases translation of bacterial proteins.

    Science.gov (United States)

    Korolev, Semen A; Zverkov, Oleg A; Seliverstov, Alexandr V; Lyubetsky, Vassily A

    2016-04-16

    Short leader genes usually do not encode stable proteins, although their importance in expression control of bacterial genomes is widely accepted. Such genes are often involved in the control of attenuation regulation. However, the abundance of leader genes suggests that their role in bacteria is not limited to regulation. Specifically, we hypothesize that leader genes increase the expression of protein-coding (structural) genes via ribosome reinitiation at the leader peptide in the case of a short distance between the stop codon of the leader gene and the start codon of the structural gene. For instance, in Actinobacteria, the frequency of leader genes at a distance of 10-11 bp is about 70 % higher than the mean frequency within the 1 to 65 bp range; and it gradually decreases as the range grows longer. A pronounced peak of this frequency-distance relationship is also observed in Proteobacteria, Bacteroidetes, Spirochaetales, Acidobacteria, the Deinococcus-Thermus group, and Planctomycetes. In contrast, this peak falls to the distance of 15-16 bp and is not very pronounced in Firmicutes; and no such peak is observed in cyanobacteria and tenericutes. Generally, this peak is typical for many bacteria. Some leader genes located close to a structural gene probably play a regulatory role as well.

  14. Ileal digestibility of amino acids in novel organic protein feedstuffs for pigs: Mussel meal(Mytilus edulis)

    OpenAIRE

    Kortelainen, Tiina; Siljander-Rasi, Hilkka; Tuori, Mikko; Partanen, Kirsi

    2014-01-01

    Abstract The objective of this study was to determine the apparent total tract digestibility (ATTD) of nu-trients and the standardised ileal digestibility (SID) of amino acids in organically produced mus-sel (Mytilus edulis) meal in growing piglets. The use of mussel meal in pig feeding is not allowed for the time being, but feed legislation in the EU concerning the use of mussel meal for pigs is in progress. The experiment was carried out with a total of 24 growing pigs, 13 gilts and ...

  15. Soybean Meal and Soy Protein Concentrate in Early Diet Elicit Different Nutritional Programming Effects on Juvenile Zebrafish.

    Science.gov (United States)

    Perera, Erick; Yúfera, Manuel

    2016-02-01

    There is now strong evidence that early nutrition plays an important role in shaping later physiology. We assessed here whether soy protein concentrate (SPC) or soybean meal (SBM) in early diet would modify zebrafish responses to these products in later life. We fed zebrafish larvae with SPC-, SBM-, or a control-diet for the first 3 days of feeding and then grew all larvae on the control diet up to juveniles. Finally, we assessed the expression in juveniles of genes involved in inflammation/immunity, the breakdown of extracellular matrix, luminal digestion, and intestinal nutrient absorption/trafficking. First feeding SBM had wider, stronger, and more persistent effects on gene expression with respect to SPC. Juveniles fed with SPC at first feeding were more prone to inflammation after refeeding with SPC than fish that never experienced SPC before. Conversely, zebrafish that faced SBM at first feeding were later less responsive to refeeding with SBM through inflammation and had higher expression of markers of peptide absorption and fatty acid transport. Results indicate that some features of inflammation/remodeling, presumably at the intestine, and nutrient absorption/transport in fish can be programmed by early nutrition. These findings sustain the rationale of using zebrafish for depicting molecular mechanisms involved in nutritional programming.

  16. 罗非鱼低鱼粉饲料中脱酚棉籽蛋白替代鱼粉的研究%Replacement of Fish Meal with Degossypolled Cottonseed Protein in Low Fish Meal Diets for Tilapia (Oreochromis niloticus)

    Institute of Scientific and Technical Information of China (English)

    林仕梅; 毛述宏; 关勇; 潘瑜; 罗琳; 罗莉

    2011-01-01

    In order to study the feasibility of replacement of fish meal with degossypolled cottonseed protein in low fish meal diets for tilapia ( Oreochromis niloticus) , three isonitrogenous and isoenergetic experimental diets were formulated by replacing 0, 50% and 100% fish meal with degossypolled cottonseed protein on basis of a practical diet (fish meal content was 6. 0% and crude protein content in fish meal was 64. 5% ), respectively. A total of 270 male genetically improved farmed tilapia (GIFT) with an average body weight of 50 g were randomly divided into 3 groups with 3 replicates per group and 30 fish per replicate, and the fish in the control group were fed the experimental diet containing 0 degossypolled cottonseed protein. The experiment lasted for 8 weeks. The results showed as follows; the final weight of tilapia in the 50% replacement level group was significantly higher than that in the control group (P 0. 05). No significant differences were found in special growth rate, protein efficiency ratio, feed efficiency and feeding rate of tilapia among all groups (P >0. 05). With increasing replacement level of degossypolled cottonseed protein, the viscerosomatic index of tilapia was significantly increased (P 0. 05). The replacement level of degossypolled cottonseed protein could significantly affect the hepatopancreas digestive enzyme activities of tilapia (P <0. 05) , and the highest values of trypsinase and amylase activities were found in the 50% replacement level group and 100% replacement level group, respectively. With increasing replacement level of degossypolled cottonseed protein, the total antioxidant capacity, activities of su-peroxide dismutase, glutamic pyruvic transaminase and glutamic oxaolacetic transaminase, and liver glycogen content in hepatopancreas of tilapia were significantly increased ( P <0. 05) , while the malondialdehyde content was significantly decreased (P <0. 05). In conclusion, the suitable replacement levels of fish meal with

  17. Surface Proteins of Streptococcus agalactiae and Related Proteins in Other Bacterial Pathogens

    OpenAIRE

    Lindahl, Gunnar; Stålhammar-Carlemalm, Margaretha; Areschoug, Thomas

    2005-01-01

    Streptococcus agalactiae (group B Streptococcus) is the major cause of invasive bacterial disease, including meningitis, in the neonatal period. Although prophylactic measures have contributed to a substantial reduction in the number of infections, development of a vaccine remains an important goal. While much work in this field has focused on the S. agalactiae polysaccharide capsule, which is an important virulence factor that elicits protective immunity, surface proteins have received incre...

  18. Chemical inhibition of bacterial protein tyrosine phosphatase suppresses capsule production.

    Science.gov (United States)

    Standish, Alistair J; Salim, Angela A; Zhang, Hua; Capon, Robert J; Morona, Renato

    2012-01-01

    Capsule polysaccharide is a major virulence factor for a wide range of bacterial pathogens, including Streptococcus pneumoniae. The biosynthesis of Wzy-dependent capsules in both gram-negative and -positive bacteria is regulated by a system involving a protein tyrosine phosphatase (PTP) and a protein tyrosine kinase. However, how the system functions is still controversial. In Streptococcus pneumoniae, a major human pathogen, the system is present in all but 2 of the 93 serotypes found to date. In order to study this regulation further, we performed a screen to find inhibitors of the phosphatase, CpsB. This led to the observation that a recently discovered marine sponge metabolite, fascioquinol E, inhibited CpsB phosphatase activity both in vitro and in vivo at concentrations that did not affect the growth of the bacteria. This inhibition resulted in decreased capsule synthesis in D39 and Type 1 S. pneumoniae. Furthermore, concentrations of Fascioquinol E that inhibited capsule also lead to increased attachment of pneumococci to a macrophage cell line, suggesting that this compound would inhibit the virulence of the pathogen. Interestingly, this compound also inhibited the phosphatase activity of the structurally unrelated gram-negative PTP, Wzb, which belongs to separate family of protein tyrosine phosphatases. Furthermore, incubation with Klebsiella pneumoniae, which contains a homologous phosphatase, resulted in decreased capsule synthesis. Taken together, these data provide evidence that PTPs are critical for Wzy-dependent capsule production across a spectrum of bacteria, and as such represents a valuable new molecular target for the development of anti-virulence antibacterials.

  19. Chemical inhibition of bacterial protein tyrosine phosphatase suppresses capsule production.

    Directory of Open Access Journals (Sweden)

    Alistair J Standish

    Full Text Available Capsule polysaccharide is a major virulence factor for a wide range of bacterial pathogens, including Streptococcus pneumoniae. The biosynthesis of Wzy-dependent capsules in both gram-negative and -positive bacteria is regulated by a system involving a protein tyrosine phosphatase (PTP and a protein tyrosine kinase. However, how the system functions is still controversial. In Streptococcus pneumoniae, a major human pathogen, the system is present in all but 2 of the 93 serotypes found to date. In order to study this regulation further, we performed a screen to find inhibitors of the phosphatase, CpsB. This led to the observation that a recently discovered marine sponge metabolite, fascioquinol E, inhibited CpsB phosphatase activity both in vitro and in vivo at concentrations that did not affect the growth of the bacteria. This inhibition resulted in decreased capsule synthesis in D39 and Type 1 S. pneumoniae. Furthermore, concentrations of Fascioquinol E that inhibited capsule also lead to increased attachment of pneumococci to a macrophage cell line, suggesting that this compound would inhibit the virulence of the pathogen. Interestingly, this compound also inhibited the phosphatase activity of the structurally unrelated gram-negative PTP, Wzb, which belongs to separate family of protein tyrosine phosphatases. Furthermore, incubation with Klebsiella pneumoniae, which contains a homologous phosphatase, resulted in decreased capsule synthesis. Taken together, these data provide evidence that PTPs are critical for Wzy-dependent capsule production across a spectrum of bacteria, and as such represents a valuable new molecular target for the development of anti-virulence antibacterials.

  20. Co-Ingestion of Whey Protein with a Carbohydrate-Rich Breakfast Does Not Affect Glycemia, Insulinemia or Subjective Appetite Following a Subsequent Meal in Healthy Males.

    Science.gov (United States)

    Allerton, Dean M; Campbell, Matthew D; Gonzalez, Javier T; Rumbold, Penny L S; West, Daniel J; Stevenson, Emma J

    2016-02-25

    We aimed to assess postprandial metabolic and appetite responses to a mixed-macronutrient lunch following prior addition of whey protein to a carbohydrate-rich breakfast. Ten healthy males (age: 24 ± 1 years; body mass index (BMI): 24.5 ± 0.7 kg/m²) completed three trials in a non-isocaloric, crossover design. A carbohydrate-rich breakfast (93 g carbohydrate; 1799 kJ) was consumed with (CHO + WP) or without (CHO) 20 g whey protein isolate (373 kJ), or breakfast was omitted (NB). At 180 min, participants consumed a mixed-macronutrient lunch meal. Venous blood was sampled at 15 min intervals following each meal and every 30 min thereafter, while subjective appetite sensations were collected every 30 min throughout. Post-breakfast insulinemia was greater after CHO + WP (time-averaged area under the curve (AUC0--180 min): 193.1 ± 26.3 pmol/L), compared to CHO (154.7 ± 18.5 pmol/L) and NB (46.1 ± 8.0 pmol/L; p 0.05). Adding whey protein to a carbohydrate-rich breakfast enhanced the acute postprandial insulin response, without influencing metabolic or appetite responses following a subsequent mixed-macronutrient meal.

  1. Bioavailability of the digestible lysine and total sulfur amino acids in meat and bone meals varying in protein quality.

    Science.gov (United States)

    Wang, X; Parsons, C M

    1998-07-01

    Experiments were conducted to determine whether the digestible Lys, Met, and TSAA in a high and low quality meat and bone meal (MBM) were totally bioavailable for protein synthesis in chicks. True digestibility of amino acids (AA) in the two MBM was determined by the precision-fed cecectomized rooster assay. Bioavailability of the digestible AA was then assessed in three slope-ratio chick growth assays using Lys-, Met-, or TSAA-deficient crystalline AA basal diets that were supplemented with varying levels of the test AA, high or low quality MBM, or AA mixtures simulating the mean digestible AA composition of the high and low quality MBM. Response parameters were weight gain, feed efficiency, body N gain, and body Lys gain in the Lys assay and weight gain and feed efficiency in the Met and TSAA assays. Bioavailability values for the digestible Lys, Met, and TSAA in the MBM and AA mixtures simulating MBM varied depending on response parameter, with values based on feed efficiency generally being highest. No consistent differences in bioavailability of the digestible AA were observed between the two MBM when all AA were considered; however, the bioavailability of the digestible Lys in the low quality MBM was lower than that in the high quality MBM for two of four performance criteria. When considering all response parameters and the AA mixture results, bioavailability of the digestible Lys and Met in the two MBM was generally 90% or greater, whereas bioavailability of the digestible TSAA was only 80% or less. The results of this study indicated that essentially all of the digestible Lys and Met in MBM were bioavailable for protein synthesis and metabolism but suggested that a significant amount of the TSAA, particularly Cys, was not bioavailable.

  2. Identification of Proteins and Peptide Biomarkers for Detecting Banned Processed Animal Proteins (PAPs) in Meat and Bone Meal by Mass Spectrometry.

    Science.gov (United States)

    Marbaix, Hélène; Budinger, Dimitri; Dieu, Marc; Fumière, Olivier; Gillard, Nathalie; Delahaut, Philippe; Mauro, Sergio; Raes, Martine

    2016-03-23

    The outbreak of bovine spongiform encephalopathy (BSE) in the United Kingdom in 1986, with processed animal proteins (PAPs) as the main vector of the disease, has led to their prohibition in feed. The progressive release of the feed ban required the development of new analytical methods to determine the exact origin of PAPs from meat and bone meal. We set up a promising MS-based method to determine the species and the source (legal or not) present in PAPs: a TCA-acetone protein extraction followed by a cleanup step, an in-solution tryptic digestion of 5 h (with a 1:20 protein/trypsin ratio), and mass spectrometry analyses, first without any a priori, with a Q-TOF, followed by a targeted triple-quadrupole analysis. Using this procedure, we were able to overcome some of the major limitations of the official methods to analyze PAPs, detecting and identifying prohibited animal products in feedstuffs by the monitoring of peptides specific for cows, pigs, and sheep in PAPs.

  3. Structural characterization and physicochemical properties of protein extracted from soybean meal assisted by steam flash-explosion with dilute acid soaking.

    Science.gov (United States)

    Zhang, Yanpeng; Yang, Ruijin; Zhang, Weinong; Hu, Zhixiong; Zhao, Wei

    2017-03-15

    The aim of this work was to analyze the influence of steam flash-explosion (SFE) with dilute acid soaking pretreatment on the structural characteristics and physiochemical properties of protein from soybean meal (SBM). The pretreatment led to depolymerisation of soy protein isolate (SPI) and formation of new protein aggregation through non-disulfide covalent bonds, which resulted in broader MW distribution of SPI. The analysis of CD spectroscopy showed that the SFE treatment induced minor changes in secondary structure, however, the intrinsic tryptophan fluorescence revealed that acid soaking and SFE treatment pronouncedly altered the tertiary structure of SPI. The protein zeta potential was shown to be increased after SFE treatment attributed to the changes in protein structure and the covalent coupling between carbohydrate and protein. These results contribute to clarifying the mechanisms of the effect of pretreatment on SPI structure, thus moving further toward implementing SFE in the processing chain of SPI.

  4. Substituição do farelo de soja pela farinha de glúten de milho na alimentação de cabras leiteiras Substitution of soybean meal protein by corn gluten meal protein in dairy goat feeding

    Directory of Open Access Journals (Sweden)

    Luiz Gonzaga Pego de Macedo

    2003-08-01

    the effect of substitution of soybean meal (SM protein by the protein from the corn gluten flour (CGF, in the milk production, milk composition, voluntary intake and plasmatic urea. The experimental design was the triple Latin square 4x4, with four periods of 21 days, being 14 days of adaptation to the diet and seven days for samples collection. The goats were fed and milked in the morning and afternoon. The substitution levels studied were: 0, 10, 30 and 50% of CGF (based in the crude protein. The substitution of the soybean meal by CGM did not affect the intake (kg/day and %BW of dry matter, crude protein and acid detergent fiber, but there was quadratic effect for neutral detergent fiber intake (kg/day and %BW. There was effect on the levels of plasmatic urea nitrogen (PUN, where the smallest values were in the intermediate levels of substitution, being the biggest values for the treatment with only SM. The milk production decreased lineally with the inclusion of CGM. The substitution levels resulted in lineal decrease in the fat production (kg/day, in the milk fat content (% and milk total solids content (%. There was quadratic effect for lactose production, being the smallest value for 31.6% of substitution level. It was no effect on in crude protein in the milk, which average was .083 kg/day. The crude protein content, lactose and total solids did not suffer effect of the substitution levels, being the average values of 2.98, 4.35 and 11.51%, respectively.

  5. Post-Meal Responses of Elongation Factor 2 (eEF2 and Adenosine Monophosphate-Activated Protein Kinase (AMPK to Leucine and Carbohydrate Supplements for Regulating Protein Synthesis Duration and Energy Homeostasis in Rat Skeletal Muscle

    Directory of Open Access Journals (Sweden)

    Donald K. Layman

    2012-11-01

    Full Text Available Previous research demonstrates that the anabolic response of muscle protein synthesis (MPS to a meal is regulated at the level of translation initiation with signals derived from leucine (Leu and insulin to activate mTORC1 signaling. Recent evidence suggests that the duration of the meal response is limited by energy status of the cell and inhibition of translation elongation factor 2 (eEF2. This study evaluates the potential to extend the anabolic meal response with post-meal supplements of Leu or carbohydrates. Adult (~256 g male Sprague-Dawley rats were food deprived for 12 h, then either euthanized before a standard meal (time 0 or at 90 or 180 min post-meal. At 135 min post-meal, rats received one of five oral supplements: 270 mg leucine (Leu270, 80:40:40 mg leucine, isoleucine, and valine (Leu80, 2.63 g carbohydrates (CHO2.6, 1 g carbohydrates (CHO1.0, or water (Sham control. Following the standard meal, MPS increased at 90 min then declined to pre-meal baseline at 180 min. Rats administered Leu270, Leu80, CHO2.6, or CHO1.0 maintained elevated rates of MPS at 180 min, while Sham controls declined from peak values. Leu80 and CHO1.0 treatments maintained MPS, but with values intermediate between Sham controls and Leu270 and CHO2.6 supplements. Consistent with MPS findings, the supplements maintained elongation activity and cellular energy status by preventing increases in AMP/ATP and phosphorylation of adenosine monophosphate-activated protein kinase (AMPK, acetyl-CoA carboxylase ACC and eEF2. The impact of the supplements on MPS and cellular energy status was in proportion to the energy content within the individual treatments (i.e., Leu270 > Leu80; CHO2.6 > CHO1.0, but the Leu supplements produced a disproportionate anabolic stimulation of MPS, eEF2 and energy status with significantly lower energy content. In summary, the incongruity between MPS and translation initiation at 180 min reflects a block in translation elongation due to

  6. Post-meal responses of elongation factor 2 (eEF2) and adenosine monophosphate-activated protein kinase (AMPK) to leucine and carbohydrate supplements for regulating protein synthesis duration and energy homeostasis in rat skeletal muscle.

    Science.gov (United States)

    Wilson, Gabriel J; Moulton, Christopher J; Garlick, Peter J; Anthony, Tracy G; Layman, Donald K

    2012-11-13

    Previous research demonstrates that the anabolic response of muscle protein synthesis (MPS) to a meal is regulated at the level of translation initiation with signals derived from leucine (Leu) and insulin to activate mTORC1 signaling. Recent evidence suggests that the duration of the meal response is limited by energy status of the cell and inhibition of translation elongation factor 2 (eEF2). This study evaluates the potential to extend the anabolic meal response with post-meal supplements of Leu or carbohydrates. Adult (~256 g) male Sprague-Dawley rats were food deprived for 12 h, then either euthanized before a standard meal (time 0) or at 90 or 180 min post-meal. At 135 min post-meal, rats received one of five oral supplements: 270 mg leucine (Leu270), 80:40:40 mg leucine, isoleucine, and valine (Leu80), 2.63 g carbohydrates (CHO2.6), 1 g carbohydrates (CHO1.0), or water (Sham control). Following the standard meal, MPS increased at 90 min then declined to pre-meal baseline at 180 min. Rats administered Leu270, Leu80, CHO2.6, or CHO1.0 maintained elevated rates of MPS at 180 min, while Sham controls declined from peak values. Leu80 and CHO1.0 treatments maintained MPS, but with values intermediate between Sham controls and Leu270 and CHO2.6 supplements. Consistent with MPS findings, the supplements maintained elongation activity and cellular energy status by preventing increases in AMP/ATP and phosphorylation of adenosine monophosphate-activated protein kinase (AMPK), acetyl-CoA carboxylase ACC and eEF2. The impact of the supplements on MPS and cellular energy status was in proportion to the energy content within the individual treatments (i.e., Leu270 > Leu80; CHO2.6 > CHO1.0), but the Leu supplements produced a disproportionate anabolic stimulation of MPS, eEF2 and energy status with significantly lower energy content. In summary, the incongruity between MPS and translation initiation at 180 min reflects a block in translation elongation due to reduced

  7. 血浆蛋白粉、血球蛋白粉及血粉三者之间的差异%Differences Among the Plasma Protein Powder Blood Protein Powder and Blood Meal

    Institute of Scientific and Technical Information of China (English)

    黄百花; 杨朝旭; 张玉民; 高荣玲; 李伟; 刘飞

    2012-01-01

    The differences among the plasma protein powder, blood protein powder and blood meal from sens-es, processing, chemical composition and freshness. The results showed that the plasma protein powder nutrition val-ue higher, blood protein powder protein content was higher, including plasma, blood protein powder processing tech-nology and safety science than blood meal, the freshness of plasma protein pouder and blood protein powder was al- so significantly higher than the blood meal, more safety.%文章主要从感官、加工工艺、化学组成和新鲜度4个方面分析比较血浆蛋白粉、血球蛋白粉和血粉的差异。结果表明,血浆蛋白粉的营养价值较高,血球蛋白粉蛋白含量较高,其中血浆、血球蛋白粉的加工工艺比血粉科学及安全,前两者的新鲜度也明显高于血粉,更易保存。

  8. The effect of temperature and bacterial growth phase on protein extraction by means of electroporation.

    Science.gov (United States)

    Haberl-Meglič, Saša; Levičnik, Eva; Luengo, Elisa; Raso, Javier; Miklavčič, Damijan

    2016-12-01

    Different chemical and physical methods are used for extraction of proteins from bacteria, which are used in variety of fields. But on a large scale, many methods have severe drawbacks. Recently, extraction by means of electroporation showed a great potential to quickly obtain proteins from bacteria. Since many parameters are affecting the yield of extracted proteins, our aim was to investigate the effect of temperature and bacterial growth phase on the yield of extracted proteins. At the same time bacterial viability was tested. Our results showed that the temperature has a great effect on protein extraction, the best temperature post treatment being 4°C. No effect on bacterial viability was observed for all temperatures tested. Also bacterial growth phase did not affect the yield of extracted proteins or bacterial viability. Nevertheless, further experiments may need to be performed to confirm this observation, since only one incubation temperature (4°C) and one incubation time before and after electroporation (0.5 and 1h) were tested for bacterial growth phase. Based on our results we conclude that temperature is a key element for bacterial membrane to stay in a permeabilized state, so more proteins flow out of bacteria into surrounding media.

  9. Effect of storage temperatures on injured escherichia coli cell populations in whey and corn meal snacks treated with a twin screw extruder

    Science.gov (United States)

    The effect of extrusion treatment parameters on injured populations of corn meal and whey protein isolate inoculated with surrogate E. coli populations has been reported. However, information on the effect of treatment parameters on injured bacterial populations of treated corn and whey protein prod...

  10. NetPhosBac - A predictor for Ser/Thr phosphorylation sites in bacterial proteins

    DEFF Research Database (Denmark)

    Miller, Martin Lee; Soufi, Boumediene; Jers, Carsten;

    2009-01-01

    predictors on bacterial systems. We used these large bacterial datasets and neural network algorithms to create the first bacteria-specific protein phosphorylation predictor: NetPhosBac. With respect to predicting bacterial phosphorylation sites, NetPhosBac significantly outperformed all benchmark predictors....... Moreover, NetPhosBac predictions of phosphorylation sites in E. coli proteins were experimentally verified on protein and site-specific levels. In conclusion, NetPhosBac clearly illustrates the advantage of taxa-specific predictors and we hope it will provide a useful asset to the microbiological community....

  11. Strategies for the recovery of active proteins through refolding of bacterial inclusion body proteins

    Directory of Open Access Journals (Sweden)

    Rinas Ursula

    2004-09-01

    Full Text Available Abstract Recent advances in generating active proteins through refolding of bacterial inclusion body proteins are summarized in conjunction with a short overview on inclusion body isolation and solubilization procedures. In particular, the pros and cons of well-established robust refolding techniques such as direct dilution as well as less common ones such as diafiltration or chromatographic processes including size exclusion chromatography, matrix- or affinity-based techniques and hydrophobic interaction chromatography are discussed. Moreover, the effect of physical variables (temperature and pressure as well as the presence of buffer additives on the refolding process is elucidated. In particular, the impact of protein stabilizing or destabilizing low- and high-molecular weight additives as well as micellar and liposomal systems on protein refolding is illustrated. Also, techniques mimicking the principles encountered during in vivo folding such as processes based on natural and artificial chaperones and propeptide-assisted protein refolding are presented. Moreover, the special requirements for the generation of disulfide bonded proteins and the specific problems and solutions, which arise during process integration are discussed. Finally, the different strategies are examined regarding their applicability for large-scale production processes or high-throughput screening procedures.

  12. Enzymatic detoxification of jojoba meal and effect of the resulting meal on food intake in rats.

    Science.gov (United States)

    Bouali, Abderrahime; Bellirou, Ahmed; Boukhatem, Noureddin; Hamal, Abdellah; Bouammali, Boufelja

    2008-05-10

    When defatted jojoba meal is used as animal food, it causes food-intake reduction and growth retardation. Detoxification procedures by chemical, microbiological, and solvent extraction methods are reported by several authors. Here we report a successful detoxification of jojoba meal using enzymes. We establish reaction conditions that yield new meal which has the same nutritional qualities in proteins as the original meal. The enzymatic reaction gives rise to one major compound to which the structure of an amide is assigned on the basis of IR, 1H and 13C NMR spectra. The effect of the resulting jojoba meal on the food intake in rats is checked. In contrast, the detoxified meal containing the amide derivatives shows no toxicological activity since rats receiving oral administration of the obtained meal show normal growth. Thus, it is expected that this meal could be used as an animal feed ingredient.

  13. Application of tung oil to improve adhesion strength and water resistance of cottonseed meal and protein adhesives on maple veneer

    Science.gov (United States)

    Cottonseed meal-based products show promise in serving as environment-friendly wood adhesives. However, their practical utilization is currently limited due to low durability and water resistant properties. In this research, we tested the improvement of adhesion strength and water resistance of cott...

  14. Extraction of phytic acid and preparation of protein isolates from rapeseed meal%菜籽粕植酸提取和分离蛋白的制备

    Institute of Scientific and Technical Information of China (English)

    潘丽军; 周俊; 姜绍通; 孙汉巨; 罗水忠; 韩智宏

    2011-01-01

    植酸和蛋白是菜籽粕中2种极具经济价值的成份.为提高菜籽粕的综合利用效果,该文以双低冷榨菜籽粕为原料,采用醋酸溶液提取植酸,在膜分离精制植酸粗提液过程中同时回收蛋白;再对植酸提取后的残余物进行蛋白分离,超滤纯化后获得高纯度的蛋白成品.响应面优化的植酸最适提取条件为:醋酸质量分数0.7%,提取温度48℃,液料比10 mL/g,提取时间1.6 h,该条件下植酸得率为1.865%.植酸粗提液中回收出的蛋白和损失植酸分别占菜籽粕的3.63%和0.395%.超滤精制的分离蛋白可达到70%~90%不同纯度的要求,蛋白中多酚含量显著减少,且植酸与硫苷未检出.%Phytic acid and protein are two kinds of valuable components in rapeseed meal. To improve comprehensive utilization in this research, phytic acid was extracted with acetum from double-low coldpressed rapeseed meal, and protein was recovered from the crude extract of phytic acid by membrane separating technology. The meal residue was dried to extract protein, which was then purified by ultrafiltration to obtain high purity product. Extraction conditions of phytic acid were optimized by response surface methodology (RSM) as follows: mass fraction of acetic acid 0.7%,extraction temperature 48℃, liquid-to-solid ratio 10 mL/g, extraction time 1.6 h. Under this condition, extraction yield was 1.865%. Protein recovered and phytic acid loss accounting for rapeseed meal were 3.63% and 0.395% respectively in crude extract of phytic acid. Purity of the protein refined by ultrafiltration was between 70% and 90%, in which the content ofpolyphenols was significantly reduced and no phytic acid and glucosinolates could be detected.

  15. Bacterial origin of a mitochondrial outer membrane protein translocase: new perspectives from comparative single channel electrophysiology.

    Science.gov (United States)

    Harsman, Anke; Niemann, Moritz; Pusnik, Mascha; Schmidt, Oliver; Burmann, Björn M; Hiller, Sebastian; Meisinger, Chris; Schneider, André; Wagner, Richard

    2012-09-07

    Mitochondria are of bacterial ancestry and have to import most of their proteins from the cytosol. This process is mediated by Tom40, an essential protein that forms the protein-translocating pore in the outer mitochondrial membrane. Tom40 is conserved in virtually all eukaryotes, but its evolutionary origin is unclear because bacterial orthologues have not been identified so far. Recently, it was shown that the parasitic protozoon Trypanosoma brucei lacks a conventional Tom40 and instead employs the archaic translocase of the outer mitochondrial membrane (ATOM), a protein that shows similarities to both eukaryotic Tom40 and bacterial protein translocases of the Omp85 family. Here we present electrophysiological single channel data showing that ATOM forms a hydrophilic pore of large conductance and high open probability. Moreover, ATOM channels exhibit a preference for the passage of cationic molecules consistent with the idea that it may translocate unfolded proteins targeted by positively charged N-terminal presequences. This is further supported by the fact that the addition of a presequence peptide induces transient pore closure. An in-depth comparison of these single channel properties with those of other protein translocases reveals that ATOM closely resembles bacterial-type protein export channels rather than eukaryotic Tom40. Our results support the idea that ATOM represents an evolutionary intermediate between a bacterial Omp85-like protein export machinery and the conventional Tom40 that is found in mitochondria of other eukaryotes.

  16. Behind the lines–actions of bacterial type III effector proteins in plant cells

    OpenAIRE

    Büttner, Daniela

    2016-01-01

    Pathogenicity of most Gram-negative plant-pathogenic bacteria depends on the type III secretion (T3S) system, which translocates bacterial effector proteins into plant cells. Type III effectors modulate plant cellular pathways to the benefit of the pathogen and promote bacterial multiplication. One major virulence function of type III effectors is the suppression of plant innate immunity, which is triggered upon recognition of pathogen-derived molecular patterns by plant receptor proteins. Ty...

  17. Functional characterisation and Mutational analysis of a bacterial dynamin-like protein, DynA

    OpenAIRE

    2015-01-01

    Membrane remodeling is a dynamic process that occurs in bacterial cells to facilitate substrate transport and to provide protection to bacteria during environmental stress. In eukaryotic cells, membrane remodeling is carried out by dynamin-like proteins (DLPs). These proteins are involved in diverse membrane-associated functions such as cargo transport via vesicles, cytokinesis, division of cell organelles and resistance to pathogens. DLPs are also conserved in bacterial species; howeve...

  18. Co-Ingestion of Whey Protein with a Carbohydrate-Rich Breakfast Does Not Affect Glycemia, Insulinemia or Subjective Appetite Following a Subsequent Meal in Healthy Males

    Directory of Open Access Journals (Sweden)

    Dean M. Allerton

    2016-02-01

    Full Text Available We aimed to assess postprandial metabolic and appetite responses to a mixed-macronutrient lunch following prior addition of whey protein to a carbohydrate-rich breakfast. Ten healthy males (age: 24 ± 1 years; body mass index (BMI: 24.5 ± 0.7 kg/m2 completed three trials in a non-isocaloric, crossover design. A carbohydrate-rich breakfast (93 g carbohydrate; 1799 kJ was consumed with (CHO + WP or without (CHO 20 g whey protein isolate (373 kJ, or breakfast was omitted (NB. At 180 min, participants consumed a mixed-macronutrient lunch meal. Venous blood was sampled at 15 min intervals following each meal and every 30 min thereafter, while subjective appetite sensations were collected every 30 min throughout. Post-breakfast insulinemia was greater after CHO + WP (time-averaged area under the curve (AUC0––180 min: 193.1 ± 26.3 pmol/L, compared to CHO (154.7 ± 18.5 pmol/L and NB (46.1 ± 8.0 pmol/L; p < 0.05, with no difference in post-breakfast (0–180 min glycemia (CHO + WP, 3.8 ± 0.2 mmol/L; CHO, 4.2 ± 0.2 mmol/L; NB, 4.2 ± 0.1 mmol/L; p = 0.247. There were no post-lunch (0–180 min effects of condition on glycemia (p = 0.492, insulinemia (p = 0.338 or subjective appetite (p > 0.05. Adding whey protein to a carbohydrate-rich breakfast enhanced the acute postprandial insulin response, without influencing metabolic or appetite responses following a subsequent mixed-macronutrient meal.

  19. Consumption of a high-fat meal containing cheese compared with a vegan alternative lowers postprandial C-reactive protein in overweight and obese individuals with metabolic abnormalities: a randomised controlled cross-over study.

    Science.gov (United States)

    Demmer, Elieke; Van Loan, Marta D; Rivera, Nancy; Rogers, Tara S; Gertz, Erik R; German, J Bruce; Zivkovic, Angela M; Smilowitz, Jennifer T

    2016-01-01

    Dietary recommendations suggest decreased consumption of SFA to minimise CVD risk; however, not all foods rich in SFA are equivalent. To evaluate the effects of SFA in a dairy food matrix, as Cheddar cheese, v. SFA from a vegan-alternative test meal on postprandial inflammatory markers, a randomised controlled cross-over trial was conducted in twenty overweight or obese adults with metabolic abnormalities. Individuals consumed two isoenergetic high-fat mixed meals separated by a 1- to 2-week washout period. Serum was collected at baseline, and at 1, 3 and 6 h postprandially and analysed for inflammatory markers (IL-6, IL-8, IL-10, IL-17, IL-18, TNFα, monocyte chemotactic protein-1 (MCP-1)), acute-phase proteins C-reactive protein (CRP) and serum amyloid-A (SAA), cellular adhesion molecules and blood lipids, glucose and insulin. Following both high-fat test meals, postprandial TAG concentrations rose steadily (P vegan-alternative test meal. A treatment effect was not observed for any other inflammatory markers; however, for both test meals, multiple markers significantly changed from baseline over the 6 h postprandial period (IL-6, IL-8, IL-18, TNFα, MCP-1, SAA). Saturated fat in the form of a cheese matrix reduced the iAUC for CRP compared with a vegan-alternative test meal during the postprandial 6 h period. The study is registered at clinicaltrials.gov under NCT01803633.

  20. Arabidopsis lysin-motif proteins LYM1 LYM3 CERK1 mediate bacterial peptidoglycan sensing and immunity to bacterial infection

    Science.gov (United States)

    Willmann, Roland; Lajunen, Heini M.; Erbs, Gitte; Newman, Mari-Anne; Kolb, Dagmar; Tsuda, Kenichi; Katagiri, Fumiaki; Fliegmann, Judith; Bono, Jean-Jacques; Cullimore, Julie V.; Jehle, Anna K.; Götz, Friedrich; Kulik, Andreas; Molinaro, Antonio; Lipka, Volker; Gust, Andrea A.; Nürnberger, Thorsten

    2011-01-01

    Recognition of microbial patterns by host pattern recognition receptors is a key step in immune activation in multicellular eukaryotes. Peptidoglycans (PGNs) are major components of bacterial cell walls that possess immunity-stimulating activities in metazoans and plants. Here we show that PGN sensing and immunity to bacterial infection in Arabidopsis thaliana requires three lysin-motif (LysM) domain proteins. LYM1 and LYM3 are plasma membrane proteins that physically interact with PGNs and mediate Arabidopsis sensitivity to structurally different PGNs from Gram-negative and Gram-positive bacteria. lym1 and lym3 mutants lack PGN-induced changes in transcriptome activity patterns, but respond to fungus-derived chitin, a pattern structurally related to PGNs, in a wild-type manner. Notably, lym1, lym3, and lym3 lym1 mutant genotypes exhibit supersusceptibility to infection with virulent Pseudomonas syringae pathovar tomato DC3000. Defects in basal immunity in lym3 lym1 double mutants resemble those observed in lym1 and lym3 single mutants, suggesting that both proteins are part of the same recognition system. We further show that deletion of CERK1, a LysM receptor kinase that had previously been implicated in chitin perception and immunity to fungal infection in Arabidopsis, phenocopies defects observed in lym1 and lym3 mutants, such as peptidoglycan insensitivity and enhanced susceptibility to bacterial infection. Altogether, our findings suggest that plants share with metazoans the ability to recognize bacterial PGNs. However, as Arabidopsis LysM domain proteins LYM1, LYM3, and CERK1 form a PGN recognition system that is unrelated to metazoan PGN receptors, we propose that lineage-specific PGN perception systems have arisen through convergent evolution. PMID:22106285

  1. EEVD motif of heat shock cognate protein 70 contributes to bacterial uptake by trophoblast giant cells

    Directory of Open Access Journals (Sweden)

    Kim Suk

    2009-12-01

    Full Text Available Abstract Background The uptake of abortion-inducing pathogens by trophoblast giant (TG cells is a key event in infectious abortion. However, little is known about phagocytic functions of TG cells against the pathogens. Here we show that heat shock cognate protein 70 (Hsc70 contributes to bacterial uptake by TG cells and the EEVD motif of Hsc70 plays an important role in this. Methods Brucella abortus and Listeria monocytogenes were used as the bacterial antigen in this study. Recombinant proteins containing tetratricopeptide repeat (TPR domains were constructed and confirmation of the binding capacity to Hsc70 was assessed by ELISA. The recombinant TPR proteins were used for investigation of the effect of TPR proteins on bacterial uptake by TG cells and on pregnancy in mice. Results The monoclonal antibody that inhibits bacterial uptake by TG cells reacted with the EEVD motif of Hsc70. Bacterial TPR proteins bound to the C-terminal of Hsc70 through its EEVD motif and this binding inhibited bacterial uptake by TG cells. Infectious abortion was also prevented by blocking the EEVD motif of Hsc70. Conclusions Our results demonstrate that surface located Hsc70 on TG cells mediates the uptake of pathogenic bacteria and proteins containing the TPR domain inhibit the function of Hsc70 by binding to its EEVD motif. These molecules may be useful in the development of methods for preventing infectious abortion.

  2. Blocking of bacterial biofilm formation by a fish protein coating

    DEFF Research Database (Denmark)

    Vejborg, Rebecca Munk; Klemm, Per

    2008-01-01

    Bacterial biofilm formation on inert surfaces is a significant health and economic problem in a wide range of environmental, industrial, and medical areas. Bacterial adhesion is generally a prerequisite for this colonization process and, thus, represents an attractive target for the development...... of biofilm-preventive measures. We have previously found that the preconditioning of several different inert materials with an aqueous fish muscle extract, composed primarily of fish muscle alpha-tropomyosin, significantly discourages bacterial attachment and adhesion to these surfaces. Here......, this proteinaceous coating is characterized with regards to its biofilm-reducing properties by using a range of urinary tract infectious isolates with various pathogenic and adhesive properties. The antiadhesive coating significantly reduced or delayed biofilm formation by all these isolates under every condition...

  3. The effect of mango waste meal in the protein:carbohydrate ratio on performance and body composition of pacamã fish (Lophiosilurus alexandri

    Directory of Open Access Journals (Sweden)

    A.M. Souza

    2015-04-01

    Full Text Available We evaluated the inclusion of peeled-mango waste meal as a source of carbohydrate in the protein:carbohydrate ratio (CP:CH on performance and chemical composition of pacamã (Lophiosilurus alexandri juveniles. One hundred and fifty fish (11.31±0.96g were stocked in sixteen 500 L tanks, fed three times daily (10% of live weight, in a system with water recirculation with biofilter. The treatments consisted of four experimental diets with decreasing levels of the ratio between crude protein and carbohydrate (1.40, 0.94, 0.56 and 0.29, with four replications per treatment. At the end of 60 days, we evaluated animal performance (final average weight gain, specific growth rate, total apparent feed intake, carcass yield, survival and physicochemical composition of the carcass. The protein:carbohydrate ratios affected all performance variables (P0.05. The carcass chemical composition variables were modified, except for mineral matter, pH and moisture. Mango meal can be used at the proportion of up to 15% in the diet for pacamã, establishing a CP:CHO ratio of 1.40 without impairing animal performance and the carcass chemical composition.

  4. The effect of substituting Nigella Sativa Meal as a source of protein in the rations of local rabbits on their productive performance and carcass traits

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    N. M. Abdullah

    2010-01-01

    Full Text Available Fifteen local male rabbits (6-8 weeks old were allocated into three nutritional groups. The first group fed standard ration, 5 and 10% of the Nigella Sativa Meal (NSM were added to the concentrated rations of the 2nd and 3rd groups replacing 36 and 72% of the soybean meal (SBM protein respectively. The feeding period lasted for eight weeks. Feed consumption and body weight gain were recorded weekly. At the end of feeding period, all rabbits were slaughtered and carcass traits were studied. No significant differences were found in total body weight gain and feed conversion rate (475, 502, 478 gm and (4.8, 4.8, 4.9 kg ration/1 kg wt. gain. Feed cost per 1 kg body gain declined 16% in the 3rd group, which cost 2294 ID, compared with the 1st group (2717 and the 2nd group (2561 ID. No significant differences in all carcass traits were found. Substituting 72% of SBM protein by NSM protein in rabbit ration showed no negative effects on all productive parameters and carcass traits.

  5. The bacterial flagellar protein export apparatus processively transports flagellar proteins even with extremely infrequent ATP hydrolysis.

    Science.gov (United States)

    Minamino, Tohru; Morimoto, Yusuke V; Kinoshita, Miki; Aldridge, Phillip D; Namba, Keiichi

    2014-12-22

    For self-assembly of the bacterial flagellum, a specific protein export apparatus utilizes ATP and proton motive force (PMF) as the energy source to transport component proteins to the distal growing end. The export apparatus consists of a transmembrane PMF-driven export gate and a cytoplasmic ATPase complex composed of FliH, FliI and FliJ. The FliI(6)FliJ complex is structurally similar to the α(3)β(3)γ complex of F(O)F(1)-ATPase. FliJ allows the gate to efficiently utilize PMF to drive flagellar protein export but it remains unknown how. Here, we report the role of ATP hydrolysis by the FliI(6)FliJ complex. The export apparatus processively transported flagellar proteins to grow flagella even with extremely infrequent or no ATP hydrolysis by FliI mutation (E211D and E211Q, respectively). This indicates that the rate of ATP hydrolysis is not at all coupled with the export rate. Deletion of FliI residues 401 to 410 resulted in no flagellar formation although this FliI deletion mutant retained 40% of the ATPase activity, suggesting uncoupling between ATP hydrolysis and activation of the gate. We propose that infrequent ATP hydrolysis by the FliI6FliJ ring is sufficient for gate activation, allowing processive translocation of export substrates for efficient flagellar assembly.

  6. Effects of diet energy concentration and an exogenous carbohydrase on growth performance of weanling pigs fed diets containing canola meal produced from high protein or conventional canola seeds.

    Science.gov (United States)

    Pedersen, T F; Liu, Y; Stein, H H

    2016-12-01

    The objectives were to determine effects of diet NE and an exogenous carbohydrase on growth performance and physiological parameters of weanling pigs fed a corn-soybean meal (SBM) diet or diets containing high protein canola meal (CM-HP) or conventional canola meal (CM-CV). A total of 492 pigs (initial BW: 9.15 ± 0.06 kg) were used in a randomized complete block design with 12 dietary treatments and 9 pens per treatment. A control diet based on corn and SBM and 4 diets containing 20% or 30% CM-HP or 20% or 30% CM-CV were formulated to a similar NE by adjusting inclusion of choice white grease. Four additional diets also contained 20% or 30% CM-HP or 20% or 30% CM-CV, but no additional choice white grease, and NE in these diets, therefore, was less than in the control diet. The control diet and the diets containing 30% CM-HP or CM-CV without increased choice white grease were also formulated with inclusion of an exogenous carbohydrase. Pigs were fed experimental diets for 22 d and 1 pig per pen was sacrificed at the conclusion of the experiment. Results indicated that compared with the control diet, there was no impact of canola meal on final BW, ADG, ADFI, or G:F, but pigs fed CM-CV had greater ( diets with reduced NE had greater ( diets with constant NE. Only minor effects of CM-HP or CM-CV on intestinal weight, gut fill, digesta pH, cecal VFA concentrations, and serum concentrations of urea N, total N, or albumin were observed, but the weight of the thyroid gland increased ( diets without the carbohydrase, but that was not the case if the carbohydrase was included in the diet (interaction, ( diets fed to weanling pigs from 2 wk postweaning did not impact growth performance compared with pigs fed a corn-SBM diet, and NE in diets containing canola meal does not have to be similar to that of corn-SBM diets. However, inclusion of CM-CV containing 4.43 µmol/g glucosinolates in the diets resulted in improved growth performance compared with inclusion of CM

  7. Growth and nitrogen metabolism of sea bass fed graded levels of nucleic acid nitrogen from yeast or RNA extract as partial substitute for protein nitrogen from fish meal

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    S. Kaushik

    2010-01-01

    Full Text Available Some studies carried out in mammalian models have shown de novo synthesis and salvage of nucleotides to be a costly metabolic process and a dietary supplementation with nucleic acids (NA or nucleotides has been suggested to result in a protein sparing action (Sanderson and He, 1994. On the other hand, high levels of dietary NA could have toxic effects and lead to disturbance in protein, lipid and carbohydrate metabolism in monogastric animals lacking uricase activity, an enzyme involved in NA degradation (Clifford and Story, 1976. So far, there is no clear indication of such effects in fish fed nucleic acid-enriched diets (Tacon and Cooke, 1980; Rumsey et al., 1992; Fournier et al., 2002. The aim of this experiment was to investigate growth response and N metabolism in juvenile sea bass (D. labrax fed diets supplying graded levels of nucleic acid N from dry brewer's yeast or RNA extract as partial substitutes for protein nitrogen provided by fish meal.

  8. Effects of dietary corn gluten meal on growth performance and protein metabolism in relation to IGF-I and TOR gene expression of juvenile cobia ( Rachycentron canadum)

    Science.gov (United States)

    Luo, Yiwen; Ai, Qinghui; Mai, Kangsen; Zhang, Wenbing; Xu, Wei; Zhang, Yanjiao; Liufu, Zhiguo

    2013-09-01

    A growth experiment was conducted on cobia ( Rachycentron canadum, initial weight 108.2 g ± 3.0 g) to investigate the effects of dietary corn gluten meal (CGM) levels on the fish growth, whole body composition and protein metabolism in relation to specific gene expression. Five isonitrogenous (crude protein 45%) and isoenergetic (gross energy 20 kJ g-1) practical diets were formulated by replacing 0% (the control), 17.5%, 35.0%, 52.5%, and 70.0% of fish meal (FM) protein with CGM protein. No significant differences were observed in the survival, feed intake (FI), specific growth rate (SGR), feed efficiency (FE) and protein productive value (PPV) among fish fed diets with 0%, 17.5%, 35.0%, and 52.5% of CGM protein. However, these indices were significantly lower in fish fed the diet with 70.0% of CGM protein than those in fish fed the control diet ( P < 0.05). The whole-body crude protein and lipid contents were significantly lower while the whole-body moisture content was significantly higher in fish fed the diet with 70.0% of CGM protein compared with the control group ( P < 0.05). When 70.0% of FM protein was replaced by CGM, plasma total protein and cholesterol contents were significantly lower than those in the control group ( P < 0.05). Fish fed the diet with 70.0% of CGM protein had significantly lower hepatic insulin-like growth factor I (IGF-I) expression levels than those in the control group ( P < 0.05). However, no significant differences were observed in hepatic target of rapamycin (TOR), dorsal muscle IGF-I and TOR expression levels among dietary treatments. Results of the present study indicated that 52.5% of FM protein could be replaced by CGM in the diets without significant influences on the growth, feed utilization and protein metabolism of juvenile cobia. The present results might be useful for developing cost effective and sustainable cobia dietary formulations.

  9. Effects of Dietary Corn Gluten Meal on Growth Performance and Protein Metabolism in Relation to IGF-I and TOR Gene Expression of Juvenile Cobia (Rachycentron canadum)

    Institute of Scientific and Technical Information of China (English)

    LUO Yiwen; AI Qinghui; MAI Kangsen; ZHANG Wenbing; XU Wei; ZHANG Yanjiao; LIUFU Zhiguo

    2013-01-01

    A growth experiment was conducted on cobia (Rachycentron canadum,initial weight 108.2g±3.0g) to investigate the effects of dietary com gluten meal (CGM) levels on the fish growth,whole body composition and protein metabolism in relation to specific gene expression.Five isonitrogenous (crude protein 45%) and isoenergetic (gross energy 20kJg-1) practical diets were formulated by replacing 0% (the control),17.5%,35.0%,52.5%,and 70.0% of fish meal (FM) protein with CGM protein.No significant differences were observed in the survival,feed intake (FI),specific growth rate (SGR),feed efficiency (FE) and protein productive value (PPV) among fish fed diets with 0%,17.5%,35.0%,and 52.5% of CGM protein.However,these indices were significantly lower in fish fed the diet with 70.0% of CGM protein than those in fish fed the control diet (P<0.05).The whole-body crude protein and lipid contents were significantly lower while the whole-body moisture content was significantly higher in fish fed the diet with 70.0% of CGM protein compared with the control group (P< 0.05).When 70.0% of FM protein was replaced by CGM,plasma total protein and cholesterol contents were significantly lower than those in the control group (P<0.05).Fish fed the diet with 70.0% of CGM protein had significantly lower hepatic insulin-like growth factor I (IGF-I) expression levels than those in the control group (P < 0.05).However,no significant differences were observed in hepatic target of rapamycin (TOR),dorsal muscle IGF-I and TOR expression levels among dietary treatments.Results of the present study indicated that 52.5% of FM protein could be replaced by CGM in the diets without significant influences on the growth,feed utilization and protein metabolism of juvenile cobia.The present results might be useful for developing cost effective and sustainable cobia dietary formulations.

  10. The Metabolizable Energy Value, Standardized Ileal Digestibility of Amino Acids in Soybean Meal, Soy Protein Concentrate and Fermented Soybean Meal, and the Application of These Products in Early-weaned Piglets.

    Science.gov (United States)

    Zhang, H Y; Yi, J Q; Piao, X S; Li, P F; Zeng, Z K; Wang, D; Liu, L; Wang, G Q; Han, X

    2013-05-01

    Three experiments were conducted to evaluate the metabolizable energy (ME) value, standardized ileal digestibility (SID) of amino acids (AA) of soybean meal (SBM), soy protein concentrate (SPC) and fermented soybean meal (FSBM), and the application of these products in early-weaned piglets. In Exp. 1, four barrows with initial body weight (BW) of 14.2±1.4 kg were used in a 4×4 Latin square design. The diet 1 contained corn as the only energy source. The other three diets replaced 25% of corn in diet 1 with one of the three soybean products, and the digestable energy (DE) and ME contents were determined by difference. In Exp. 2, four barrows (initial BW of 18.2±1.5 kg) were fitted with ileal T-cannulas and allotted to a 4×4 Latin square design. Three cornstarch-based diets were formulated using each of the soybean products as the sole source of AA. A nitrogen-free diet was also formulated to measure endogenous losses of AA. In Exp. 3, ninety six piglets (initial BW of 5.6±0.9 kg) weaned at 21±2 d were blocked by weight and assigned to one of three treatments for a 21-d growth performance study. The control diet was based on corn and SBM, the two treatments' diets contained either 10% SPC or FSBM and were formulated to same SID lysine to ME ratio of 3.6 g/Mcal. The results showed that the ME content of SPC was greater than SBM (p<0.05). The SID of most AA in SPC was greater than the SID of AA in SBM (p<0.05). For the essential AA, the SID of histidine, isoleucine, leucine, lysine and threonine in FSBM were greater than in SBM (p<0.05). Even though they were fed same SID lysine to ME ratio of 3.6 g/Mcal diets, pigs fed SPC and FSBM diets had greater weight gain, G:F (p<0.05) and better fecal score (p<0.05) than pigs fed SBM diet. In conclusion, SPC showed a higher ME content and SID of AA than the SBM. SID of some essential AA in FSBM was higher than SBM and was similar with SPC. But the lower antigenic proteins and anti-nutritional factors content in SPC and

  11. Fracionamento de carboidratos e proteínas de silagens de capim-elefante com casca de café, farelo de cacau ou farelo de mandioca Fractioning of carbohydrates and protein of elephant grass silages with coffee hulls, cocoa meal and cassava meal

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    Aureliano José Vieira Pires

    2009-03-01

    Full Text Available Este experimento foi conduzido para avaliar as frações que compõem os carboidratos e as proteínas da silagem de capim-elefante com 15% casca de café, farelo de cacau ou farelo de mandioca. A adição dos co-produtos no momento da ensilagem foi realizada na base da matéria natural (peso/peso, com dez repetições por tipo de silagem. O maior teor de carboidratos totais foi observado na silagem com farelo de mandioca e o menor, na silagem com farelo de cacau, seguida das silagens controle e com casca de café. Maiores valores de carboidratos não-fibrosos (A+B1 também foram verificados para as silagens com farelo de mandioca. Os menores valores de fração indigestível (C, %CT foram observados para a silagem com farelo de mandioca, enquanto as silagens com casca de café e farelo de cacau apresentaram os maiores valores desta fração. A silagem com farelo de cacau apresentou os maiores valores de proteína bruta e foi seguida das silagens com casca de café, controle e com farelo de mandioca. A presença dos aditivos influenciou as frações protéicas da silagem de capim-elefante: os maiores valores de fração A (%PB foram determinados nas silagens controle e com farelo de mandioca. Apesar do maior valor protéico, as silagens com farelo de cacau e casca de café apresentaram os maiores valores de fração indigestível de proteína (C, %PB. A adição de farelo de cacau e casca de café ao capim-elefante no momento da ensilagem aumenta as frações indigestíveis de carboidratos e de proteína da silagem. O farelo de mandioca ensilado com capim-elefante é um bom aditivo para a produção de silagem.This experiment was carried out to evaluate the fractions that compose carbohydrates and protein from elephant grass silage with 15% of coffee hulls, cocoa meal or cassava meal. The addition of residues at the ensilage moment was performed in natural matter basis (weight/weight, with ten replicates per treatment. The addition of residues at

  12. The relative merit of ruminal undegradable protein from soybean meal or soluble fiber from beet pulp to improve nitrogen utilization in dairy cows.

    Science.gov (United States)

    Borucki Castro, S I; Phillip, L E; Lapierre, H; Jardon, P W; Berthiaume, R

    2008-10-01

    Early lactating dairy cows were used to determine whether the replacement of solvent-extracted soybean meal [SSBM; a source of rumen-degradable protein (RDP)] with expeller soybean meal (ESBM; a source of rumen-undegradable protein), or the replacement of high-moisture shelled corn (HMSC) with beet pulp (a source of soluble fiber) would be effective in improving efficiency of N usage for milk production. The study was designed as a replicated 4 x 4 Latin square with 21-d periods. Eight multiparous Holstein cows were fed, ad libitum, the following diets, which were based on alfalfa silage and HMSC, and formulated to be isocaloric: 1) basal diet without a protein supplement (negative control diet: NC); 2) NC supplemented with solvent-extracted SBM (diet SSBM); 3) NC supplemented with expeller SBM (diet ESBM); 4) SSBM in which unmolassed dried beet pulp replaced half of the HMSC (diet SSBMBP). Compared with diet NC, protein supplementation increased intake of organic matter and dry matter. Milk and milk protein yields were lower with NC but this diet resulted in the greatest efficiency of N usage for milk production (30% milk N/N intake). Supplementation with ESBM, a proven source of RUP, increased plasma concentrations of histidine and branched-chain amino acids, and reduced milk urea N concentration, but failed to improve the yields of milk or milk protein. Milk fat yield tended to decrease with RUP supplementation. Replacing part of HMSC with soluble fiber from beet pulp (SSBMBP) tended to decrease milk production compared with SSBM; the effect was due to a reduction in dry matter intake. There were no differences among diets SSBM, ESBM, or SSBMBP in urinary excretion of purine derivatives. Neither substitution of ESBM for SSBM nor partial replacement of HMSC with beet pulp altered the efficiency of N usage for milk production or manure N excretion.

  13. 多菌种固态发酵对豆粕、棉籽粕和花生粕组成的混合蛋白原料的影响%Effect of multi-strain solid state fermentation on mixed protein feed composed of soybean meal, cottonseed meal and peanut meal

    Institute of Scientific and Technical Information of China (English)

    李旺军; 方华; 夏佳吉; 王玲; 季春源

    2011-01-01

    The active bacteria number and nutrient substances were analyzed during mixed culture solid state fermentation by Bacillus subitilis and Lactobacillus bulgaricus ,? With soybean meal, cottonseed meal and peanut meal as mixed solid protein feed. The Results showed that the colony formation unit (cfu) of Bacillus subitilis and Lactobacillus bulgaricus were 3. 1×108 and 4. 45×108 in fermented products, respectively. The content of lactate was 1. 98% {Meanwhile, the large molecular weight of proteins was nearly degraded after fermentation. Compared to the unfermented protein feed,the content of crude protein increased by 7. 89%,and the contents of oligo-peptide increased by 129. 36%. The anti-nutritional factors (stachyose and raffi-nose) almost completely degraded, as well as producing a certain amount of reducing sugar.%以枯草芽孢杆菌和保加利亚乳杆菌为试验菌株,对豆粕、棉籽粕和花生粕组成的混合蛋白原料样品进行多菌种发酵处理,检测发酵过程中的活菌数和营养物质的变化.结果表明:发酵结束后混合蛋白原料样品中枯草芽孢杆菌活菌数为3.1×108 cfu/g,保加利亚乳杆菌活菌数为4.45×108 cfu/g,乳酸含量为1.98%,大分子蛋白几乎完全分解成小分子蛋白,粗蛋白质含量比发酵前提高了7.89%,寡肽含量比发酵前提高了129.36%,抗营养因子(水苏糖和棉籽糖)几乎完全降解,同时产生了一定量的还原糖.

  14. Evidence for a bacterial lipopolysaccharide-recognizing G-protein-coupled receptor in the bacterial engulfment by Entamoeba histolytica.

    Science.gov (United States)

    Brewer, Matthew T; Agbedanu, Prince N; Zamanian, Mostafa; Day, Tim A; Carlson, Steve A

    2013-11-01

    Entamoeba histolytica is the causative agent of amoebic dysentery, a worldwide protozoal disease that results in approximately 100,000 deaths annually. The virulence of E. histolytica may be due to interactions with the host bacterial flora, whereby trophozoites engulf colonic bacteria as a nutrient source. The engulfment process depends on trophozoite recognition of bacterial epitopes that activate phagocytosis pathways. E. histolytica GPCR-1 (EhGPCR-1) was previously recognized as a putative G-protein-coupled receptor (GPCR) used by Entamoeba histolytica during phagocytosis. In the present study, we attempted to characterize EhGPCR-1 by using heterologous GPCR expression in Saccharomyces cerevisiae. We discovered that bacterial lipopolysaccharide (LPS) is an activator of EhGPCR-1 and that LPS stimulates EhGPCR-1 in a concentration-dependent manner. Additionally, we demonstrated that Entamoeba histolytica prefers to engulf bacteria with intact LPS and that this engulfment process is sensitive to suramin, which prevents the interactions of GPCRs and G-proteins. Thus, EhGPCR-1 is an LPS-recognizing GPCR that is a potential drug target for treatment of amoebiasis, especially considering the well-established drug targeting to GPCRs.

  15. Effect of diets containing potato protein or soya bean meal on the incidence of spontaneously-occurring subclinical necrotic enteritis and the physiological response in broiler chickens.

    Science.gov (United States)

    Fernando, P S; Rose, S P; Mackenzie, A M; Silva, S S P

    2011-02-01

    1. An experiment was conducted to compare and explain the incidence of spontaneously occurring subclinical necrotic enteritis in broiler chickens that were fed on two practical broiler diets that differed in the major protein concentrates (soya bean meal or potato protein concentrates) and examine the relationships between the severity of the disease and the growth performance and physiological responses of the chickens. 2. A total of 840, 20-d-old birds were randomly allocated to 12 pens. Two maize-based nutritionally complete diets that either contained some potato protein or soya bean meal as the major protein supplement were fed for 16 d. Twelve birds were randomly sampled from each pen at the end of the feeding period and their blood sampled and intestinal tracts and livers dissected. 3. The birds fed on the potato protein diet had a significantly 7·7% lower feed intake and a significantly 7·8% lower growth rate compared with the birds fed on the soya-based diet. There were no significant differences in feed conversion efficiency or mortality. There were no differences in the determined apparent metabolisable energy concentrations, however, the apparent dry matter digestibility of the potato protein diet was significantly higher than that of the soya based diet and the apparent crude protein digestibility of the potato protein diet was significantly lower. 4. A significantly higher alpha toxin antibody titre was found in the birds fed on the potato protein diet compared with those fed on the soya protein diet. There was a significantly increased incidence of hepatic lesions in the birds fed on the potato protein diet compared with the birds fed on the soya diet. The mean incidence of intestinal necroses tended to be greater in the birds fed on the potato protein diet (23·6%) compared with the birds fed on the soya-based diet (15·3%). 5. There was a significant linear relationship between ileal digesta sialic acid concentration and serum alpha toxin

  16. Bacterial Vegetative Insecticidal Proteins (Vip) from Entomopathogenic Bacteria.

    Science.gov (United States)

    Chakroun, Maissa; Banyuls, Núria; Bel, Yolanda; Escriche, Baltasar; Ferré, Juan

    2016-06-01

    Entomopathogenic bacteria produce insecticidal proteins that accumulate in inclusion bodies or parasporal crystals (such as the Cry and Cyt proteins) as well as insecticidal proteins that are secreted into the culture medium. Among the latter are the Vip proteins, which are divided into four families according to their amino acid identity. The Vip1 and Vip2 proteins act as binary toxins and are toxic to some members of the Coleoptera and Hemiptera. The Vip1 component is thought to bind to receptors in the membrane of the insect midgut, and the Vip2 component enters the cell, where it displays its ADP-ribosyltransferase activity against actin, preventing microfilament formation. Vip3 has no sequence similarity to Vip1 or Vip2 and is toxic to a wide variety of members of the Lepidoptera. Its mode of action has been shown to resemble that of the Cry proteins in terms of proteolytic activation, binding to the midgut epithelial membrane, and pore formation, although Vip3A proteins do not share binding sites with Cry proteins. The latter property makes them good candidates to be combined with Cry proteins in transgenic plants (Bacillus thuringiensis-treated crops [Bt crops]) to prevent or delay insect resistance and to broaden the insecticidal spectrum. There are commercially grown varieties of Bt cotton and Bt maize that express the Vip3Aa protein in combination with Cry proteins. For the most recently reported Vip4 family, no target insects have been found yet.

  17. Discovery of an archetypal protein transport system in bacterial outer membranes.

    Science.gov (United States)

    Selkrig, Joel; Mosbahi, Khedidja; Webb, Chaille T; Belousoff, Matthew J; Perry, Andrew J; Wells, Timothy J; Morris, Faye; Leyton, Denisse L; Totsika, Makrina; Phan, Minh-Duy; Celik, Nermin; Kelly, Michelle; Oates, Clare; Hartland, Elizabeth L; Robins-Browne, Roy M; Ramarathinam, Sri Harsha; Purcell, Anthony W; Schembri, Mark A; Strugnell, Richard A; Henderson, Ian R; Walker, Daniel; Lithgow, Trevor

    2012-04-01

    Bacteria have mechanisms to export proteins for diverse purposes, including colonization of hosts and pathogenesis. A small number of archetypal bacterial secretion machines have been found in several groups of bacteria and mediate a fundamentally distinct secretion process. Perhaps erroneously, proteins called 'autotransporters' have long been thought to be one of these protein secretion systems. Mounting evidence suggests that autotransporters might be substrates to be secreted, not an autonomous transporter system. We have discovered a new translocation and assembly module (TAM) that promotes efficient secretion of autotransporters in proteobacteria. Functional analysis of the TAM in Citrobacter rodentium, Salmonella enterica and Escherichia coli showed that it consists of an Omp85-family protein, TamA, in the outer membrane and TamB in the inner membrane of diverse bacterial species. The discovery of the TAM provides a new target for the development of therapies to inhibit colonization by bacterial pathogens.

  18. Impact of second line limiting amino acids’ deficiency in broilers fed low protein diets with rapeseed meal and de-oiled rice bran

    Directory of Open Access Journals (Sweden)

    C. Basavanta Kumar

    2015-03-01

    Full Text Available Aim: To study the impact of deficiency of second line limiting amino acids (SLAA; valine, isoleucine and tryptophan on the production performance and carcass characteristics of commercial broilers. Materials and Methods: A control (T1 corn-soy diet was formulated to contain all essential AA on standardized ileal digestible basis; While in T2-a ‘moderate SLAA deficit’ diet was formulated by replacement of soybean meal with 6% rapeseed meal and T3-a ‘high SLAA deficit’ diet was formulated by replacement of soybean meal with 6% de-oiled rice bran. Each of these treatments was allotted to six replicates of ten chicks each. During the 42 days experimental period, growth performance, carcass parameters and intake of metabolizable energy (ME, crude protein (CP and AA were studied. Results: The cumulative body weight gain, feed conversion ratio, carcass cut weights and yields of carcass, breast and thighs were decreased (p<0.05 in T3 compared to T1. The absolute intake of ME, lysine, methionine + cysteine and threonine were not affected while intake of CP and all SLAA were reduced in SLAA deficit diets. The relative intake of ME, lysine, methionine + cysteine, threonine and SLAA reduced in T3 in comparison to T1. The relative weights of internal organs were not affected by treatments while the abdominal fat percentage was increased linearly to the magnitude of SLAA deficiency. Conclusion: The deficiency of SLAA decreased performance, carcass yields and impaired utilization of ME, CP and AA linearly to the magnitude of the deficiency.

  19. Rho-modifying bacterial protein toxins from Photorhabdus species.

    Science.gov (United States)

    Jank, Thomas; Lang, Alexander E; Aktories, Klaus

    2016-06-15

    Photorhabdus bacteria live in symbiosis with entomopathogenic nematodes. The nematodes invade insect larvae, where they release the bacteria, which then produce toxins to kill the insects. Recently, the molecular mechanisms of some toxins from Photorhabdus luminescens and asymbiotica have been elucidated, showing that GTP-binding proteins of the Rho family are targets. The tripartite Tc toxin PTC5 from P. luminescens activates Rho proteins by ADP-ribosylation of a glutamine residue, which is involved in GTP hydrolysis, while PaTox from Photorhabdus asymbiotica inhibits the activity of GTPases by N-acetyl-glucosaminylation at tyrosine residues and activates Rho proteins indirectly by deamidation of heterotrimeric G proteins.

  20. A high protein moderate carbohydrate diet fed at discrete meals reduces early progression of N-methyl-N-nitrosourea-induced breast tumorigenesis in rats

    Directory of Open Access Journals (Sweden)

    Singletary Keith W

    2010-01-01

    Full Text Available Abstract Breast cancer is the most prevalent cancer in American women. Dietary factors are thought to have a strong influence on breast cancer incidence. This study utilized a meal-feeding protocol with female Sprague-Dawley rats to evaluate effects of two ratios of carbohydrate:protein on promotion and early progression of breast tissue carcinomas. Mammary tumors were induced by N-methyl-N-nitrosourea (MNU at 52 d of age. Post-induction, animals were assigned to consume either a low protein high carbohydrate diet (LPHC; 15% and 60% of energy, respectively or a high protein moderate carbohydrate diet (HPMC; 35% and 40% of energy, respectively for 10 wk. Animals were fed 3 meals/day to mimic human absorption and metabolism patterns. The rate of palpable tumor incidence was reduced in HPMC relative to LPHC (12.9 ± 1.4%/wk vs. 18.2 ± 1.3%/wk. At 3 wk, post-prandial serum insulin was larger in the LPHC relative to HPMC (+136.4 ± 33.1 pmol/L vs. +38.1 ± 23.4 pmol/L, while at 10 wk there was a trend for post-prandial IGF-I to be increased in HPMC (P = 0.055. There were no differences in tumor latency, tumor surface area, or cumulative tumor mass between diet groups. The present study provides evidence that reducing the dietary carbohydrate:protein ratio attenuates the development of mammary tumors. These findings are consistent with reduced post-prandial insulin release potentially diminishing the proliferative environment required for breast cancer tumors to progress.

  1. Discovering the bacterial circular proteins : bacteriocins, cyanobactins, and pilins

    NARCIS (Netherlands)

    Montalban-Lopez, Manuel; Sanchez-Hidalgo, Marina; Cebrian, Ruben; Maqueda, Mercedes

    2012-01-01

    Over recent years, several examples of natural ribosomally synthesized circular proteins and peptides from diverse organisms have been described. They are a group of proteins for which the precursors must be post-translationally modified to join the N and C termini with a peptide bond. This feature

  2. Cramble meal: evaluation, improvement and comparison with rapeseed meal.

    NARCIS (Netherlands)

    Liu, Y.G.

    1994-01-01

    Crambe abyssinica has gradually been introduced in agriculture as a new oil-bearing crop. Its oil contains 55 to 60% erucic acid (C22:1, Δ13), desirable as lubricants, plastic additives or as a raw material for chemical synthesis. The defatted meal has high protein content which provides potential a

  3. Two meals with different carbohydrate, fat and protein contents render equivalent postprandial plasma levels of calprotectin, cortisol, triglycerides and zonulin.

    Science.gov (United States)

    Ohlsson, Bodil; Darwiche, Gassan; Roth, Bodil; Höglund, Peter

    2016-11-01

    The aim was to compare postprandial plasma levels of calprotectin, cortisol, triglycerides and zonulin between a control breakfast and a moderately low-carbohydrate test breakfast, given randomly after 10-h fast. Blood samples were collected before and repeatedly after the meal. Plasma calprotectin, cortisol, triglycerides and zonulin were analyzed. The total area under the curve (tAUC) and change in AUC from baseline (dAUC) were calculated. Ratios between the test and control values were calculated to investigate equivalence. Healthy volunteers (8 men and 12 women; 46.0 ± 14.5 years) were included. tAUCs of cortisol and triglycerides did not differ between the breakfasts (p = 0.158 versus p = 0.579). Cortisol dAUCs were decreased and triglyceride dAUCs were increased after both breakfasts, with no differences between the breakfasts (p = 0.933 versus p = 0.277). Calprotectin and zonulin levels were unaffected. The meals were bioequivalent for cortisol, triglycerides and zonulin, but not for calprotectin.

  4. Effect of storage temperature on survival and recovery of thermal and extrusion injured Escherichia coli populations in whey protein concentrate and corn meal

    Science.gov (United States)

    In a previous study, we reported viability loss of Escherichia coli populations in corn (CP) and whey protein products (WPP) extruded at different temperatures. However, information on the effect of storage temperatures on injured bacterial populations was not addressed. The objective of this study ...

  5. Horizontal gene transfer of zinc and non-zinc forms of bacterial ribosomal protein S4

    Directory of Open Access Journals (Sweden)

    Luthey-Schulten Zaida

    2009-07-01

    Full Text Available Abstract Background The universal ribosomal protein S4 is essential for the initiation of small subunit ribosomal assembly and translational accuracy. Being part of the information processing machinery of the cell, the gene for S4 is generally thought of as being inherited vertically and has been used in concatenated gene phylogenies. Here we report the evolution of ribosomal protein S4 in relation to a broad sharing of zinc/non-zinc forms of the gene and study the scope of horizontal gene transfer (HGT of S4 during bacterial evolution. Results In this study we present the complex evolutionary history of ribosomal protein S4 using 660 bacterial genomes from 16 major bacterial phyla. According to conserved characteristics in the sequences, S4 can be classified into C+ (zinc-binding and C- (zinc-free variants, with 26 genomes (mainly from the class Clostridia containing genes for both. A maximum likelihood phylogenetic tree of the S4 sequences was incongruent with the standard bacterial phylogeny, indicating a departure from strict vertical inheritance. Further analysis using the genome content near the S4 genes, which are usually located in a conserved gene cluster, showed not only that HGT of the C- gene had occurred at various stages of bacterial evolution, but also that both the C- and C+ genes were present before the individual phyla diverged. To explain the latter, we theorize that a gene pool existed early in bacterial evolution from which bacteria could sample S4 gene variants, according to environmental conditions. The distribution of the C+/- variants for seven other zinc-binding ribosomal proteins in these 660 bacterial genomes is consistent with that seen for S4 and may shed light on the evolutionary pressures involved. Conclusion The complex history presented for "core" protein S4 suggests the existence of a gene pool before the emergence of bacterial lineages and reflects the pervasive nature of HGT in subsequent bacterial evolution

  6. 葵花籽粕蛋白质提取工艺参数优化%Parameters Optimization of the Extraction Technology of Protein from Sunflower Meal

    Institute of Scientific and Technical Information of China (English)

    加列西·马那甫; 景伟文; 吐力吾汗·阿米汗

    2014-01-01

    To study the extraction technology of protein from sunflower meal using salt extraction. Based on the single-factor test,the extraction factors of NaCl concentration,extraction temperature and water/dry ratio were optimized using the response surface methodology with the extraction rate of protein as the response value. As a result ,the optimum extraction conditions of protein from sunflower meal were 1.51 mol/L of NaCl concentration , 1∶12.88 (g/mL) of dry/water ratio,60.27℃of extraction temperature. Under these conditions,the extraction rate of chlorogenic acid was 36.64%.%研究葵花籽粕蛋白质盐提法提取最佳工艺。在单因素试验的基础上,选取NaCl浓度、提取温度和料液比为自变量,以蛋白质提取率为响应值,利用响应面法对葵花籽粕蛋白质的提取工艺进行优化,得到回归方程的预测模型,该模型能较好的反映各因素与响应值之间的关系。最佳提取工艺条件为,NaCl浓度1.51 mol/L、料液比1∶12.88(g/mL)、提取温度60.27℃。在此条件下,蛋白质的提取率为36.64%。

  7. Behind the lines–actions of bacterial type III effector proteins in plant cells

    Science.gov (United States)

    Büttner, Daniela

    2016-01-01

    Pathogenicity of most Gram-negative plant-pathogenic bacteria depends on the type III secretion (T3S) system, which translocates bacterial effector proteins into plant cells. Type III effectors modulate plant cellular pathways to the benefit of the pathogen and promote bacterial multiplication. One major virulence function of type III effectors is the suppression of plant innate immunity, which is triggered upon recognition of pathogen-derived molecular patterns by plant receptor proteins. Type III effectors also interfere with additional plant cellular processes including proteasome-dependent protein degradation, phytohormone signaling, the formation of the cytoskeleton, vesicle transport and gene expression. This review summarizes our current knowledge on the molecular functions of type III effector proteins with known plant target molecules. Furthermore, plant defense strategies for the detection of effector protein activities or effector-triggered alterations in plant targets are discussed. PMID:27526699

  8. Reversals and collisions optimize protein exchange in bacterial swarms

    Science.gov (United States)

    Amiri, Aboutaleb; Harvey, Cameron; Buchmann, Amy; Christley, Scott; Shrout, Joshua D.; Aranson, Igor S.; Alber, Mark

    2017-03-01

    Swarming groups of bacteria coordinate their behavior by self-organizing as a population to move over surfaces in search of nutrients and optimal niches for colonization. Many open questions remain about the cues used by swarming bacteria to achieve this self-organization. While chemical cue signaling known as quorum sensing is well-described, swarming bacteria often act and coordinate on time scales that could not be achieved via these extracellular quorum sensing cues. Here, cell-cell contact-dependent protein exchange is explored as a mechanism of intercellular signaling for the bacterium Myxococcus xanthus. A detailed biologically calibrated computational model is used to study how M. xanthus optimizes the connection rate between cells and maximizes the spread of an extracellular protein within the population. The maximum rate of protein spreading is observed for cells that reverse direction optimally for swarming. Cells that reverse too slowly or too fast fail to spread extracellular protein efficiently. In particular, a specific range of cell reversal frequencies was observed to maximize the cell-cell connection rate and minimize the time of protein spreading. Furthermore, our findings suggest that predesigned motion reversal can be employed to enhance the collective behavior of biological synthetic active systems.

  9. Protein oxidation implicated as the primary determinant of bacterial radioresistance.

    Directory of Open Access Journals (Sweden)

    Michael J Daly

    2007-04-01

    Full Text Available In the hierarchy of cellular targets damaged by ionizing radiation (IR, classical models of radiation toxicity place DNA at the top. Yet, many prokaryotes are killed by doses of IR that cause little DNA damage. Here we have probed the nature of Mn-facilitated IR resistance in Deinococcus radiodurans, which together with other extremely IR-resistant bacteria have high intracellular Mn/Fe concentration ratios compared to IR-sensitive bacteria. For in vitro and in vivo irradiation, we demonstrate a mechanistic link between Mn(II ions and protection of proteins from oxidative modifications that introduce carbonyl groups. Conditions that inhibited Mn accumulation or Mn redox cycling rendered D. radiodurans radiation sensitive and highly susceptible to protein oxidation. X-ray fluorescence microprobe analysis showed that Mn is globally distributed in D. radiodurans, but Fe is sequestered in a region between dividing cells. For a group of phylogenetically diverse IR-resistant and IR-sensitive wild-type bacteria, our findings support the idea that the degree of resistance is determined by the level of oxidative protein damage caused during irradiation. We present the case that protein, rather than DNA, is the principal target of the biological action of IR in sensitive bacteria, and extreme resistance in Mn-accumulating bacteria is based on protein protection.

  10. Assembly of β-barrel proteins into bacterial outer membranes.

    Science.gov (United States)

    Selkrig, Joel; Leyton, Denisse L; Webb, Chaille T; Lithgow, Trevor

    2014-08-01

    Membrane proteins with a β-barrel topology are found in the outer membranes of Gram-negative bacteria and in the plastids and mitochondria of eukaryotic cells. The assembly of these membrane proteins depends on a protein folding reaction (to create the barrel) and an insertion reaction (to integrate the barrel within the outer membrane). Experimental approaches using biophysics and biochemistry are detailing the steps in the assembly pathway, while genetics and bioinformatics have revealed a sophisticated production line of cellular components that catalyze the assembly pathway in vivo. This includes the modular BAM complex, several molecular chaperones and the translocation and assembly module (the TAM). Recent screens also suggest that further components of the pathway might remain to be discovered. We review what is known about the process of β-barrel protein assembly into membranes, and the components of the β-barrel assembly machinery. This article is part of a Special Issue entitled: Protein trafficking and secretion in bacteria. Guest Editors: Anastassios Economou and Ross Dalbey.

  11. Sunflower meal concentrations in Massai grass silage

    Directory of Open Access Journals (Sweden)

    Máikal S. Borja

    2012-08-01

    Full Text Available Objetive. This experiment was conducted to evaluate the best sunflower meal concentration in Massai grass silage. Materials and methods. The treatments were composed of 0, 8, 16, and 24% sunflower meal (natural matter basis during ensiling of Massai grass, with four repetitions. Results. The regression equation showed that the inclusion of sunflower meal between 2.14% and 13.91% obtained a silage dry matter between 25 and 35%, which are the values recommended for the production of high quality silage. The addition of sunflower meal showed a linear increase in crude protein, reaching 18% DM with the highest concentration of sunflower meal. The highest feed value index was obtained with the addition of 24% sunflower meal in the silage. The estimated total digestible nutrient of silage increased linearly with sunflower meal concentration. The silage pH values had a quadratic effect, reaching the lowest value (4.1 with 15% sunflower meal addition. Conclusions. Based on the chemical composition and forage quality, a concentration of 14% sunflower meal should be used for high-quality silage with good nutritional value.

  12. A simple yeast-based strategy to identify host cellular processes targeted by bacterial effector proteins.

    Directory of Open Access Journals (Sweden)

    Eran Bosis

    Full Text Available Bacterial effector proteins, which are delivered into the host cell via the type III secretion system, play a key role in the pathogenicity of gram-negative bacteria by modulating various host cellular processes to the benefit of the pathogen. To identify cellular processes targeted by bacterial effectors, we developed a simple strategy that uses an array of yeast deletion strains fitted into a single 96-well plate. The array is unique in that it was optimized computationally such that despite the small number of deletion strains, it covers the majority of genes in the yeast synthetic lethal interaction network. The deletion strains in the array are screened for hypersensitivity to the expression of a bacterial effector of interest. The hypersensitive deletion strains are then analyzed for their synthetic lethal interactions to identify potential targets of the bacterial effector. We describe the identification, using this approach, of a cellular process targeted by the Xanthomonas campestris type III effector XopE2. Interestingly, we discover that XopE2 affects the yeast cell wall and the endoplasmic reticulum stress response. More generally, the use of a single 96-well plate makes the screening process accessible to any laboratory and facilitates the analysis of a large number of bacterial effectors in a short period of time. It therefore provides a promising platform for studying the functions and cellular targets of bacterial effectors and other virulence proteins.

  13. REVIEW ARTICLE: DNA protein interactions and bacterial chromosome architecture

    Science.gov (United States)

    Stavans, Joel; Oppenheim, Amos

    2006-12-01

    Bacteria, like eukaryotic organisms, must compact the DNA molecule comprising their genome and form a functional chromosome. Yet, bacteria do it differently. A number of factors contribute to genome compaction and organization in bacteria, including entropic effects, supercoiling and DNA-protein interactions. A gamut of new experimental techniques have allowed new advances in the investigation of these factors, and spurred much interest in the dynamic response of the chromosome to environmental cues, segregation, and architecture, during both exponential and stationary phases. We review these recent developments with emphasis on the multifaceted roles that DNA-protein interactions play.

  14. Identification of Dominant Immunogenic Bacteria and Bacterial Proteins in Periodontitis

    DEFF Research Database (Denmark)

    Agerbæk, Mette Rylev; Haubek, Dorte; Birkelund, Svend

    Marginal periodontitis is considered an infectious disease that triggers host inflammatory responses resulting in destruction of the periodontium. A complex biofilm of bacteria is associated with periodontitis. Some species have been identified as putative pathogens such as Porphyromonas gingivalis...... (P.g) and Actinobacillus actinomycetemcomitans (A.a), but the identity of dominate immunogens of these bacteria is poorly elucidated. The aim of the study was to identify dominant immunogenic proteins of P.g and A.a in patients suffering from chronic and aggressive periodontitis by proteomic analysis...... will be able to identify immunodominant proteins and potentially important virulence factors of putative periodontal pathogens....

  15. 鱼粉质量对中国对虾、真鲷、饲料转化率和蛋白质消化率的影响%Influence of fish meal quality on growth,feed conversion rate and protein digestibility in shrimp (Penaeus chinensis ) and red seabream (Pagrosomus major)

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The effect of fishmeal quality on growth,feed conversion ratio and protein digestibility was studied in a growth experiment with shrimp and red seabream.The shrimp and fish were fed three diets varing in the quality of the fishmeal used in the respective feeds: low quality fish meal,good quality fish meal,and Peru fish meal.The experiment lasted for 2 months.The shrimp and fish fed the feed with good quality fish meal showed significantly better feed conversion ratio,weight gain rate,protein digestibility than the other groups.

  16. Effect of Bacillus mucilaginosus on weathering of phosphorite and a preliminary analysis of bacterial proteins

    Institute of Scientific and Technical Information of China (English)

    CHEN Shu; LIAN Bin; LIU Congqiang

    2008-01-01

    The authors investigated the effect of Bacillus mucilaginosus on weathering of phosphorite. Analysis of different proteins was of significance in exploring the molecular biological mechanism in the bacterial weathering process. The concrete methods are described as follows: Mineral powder was put into liquid culture medium and B. mucilaginosus was incubated in the medium. The control (group) had no mineral powder in the medium. The treatments and controls were cultured simultaneously under the same condition. In a few days, the supernatant was filtrated, the main cations (Ca2+, Mg2+, Na+, Mn2+, Al3+, Fe3+, K+) were measured by ICP-OES, and the contents of water soluble phosphorus (Pws) and silicon (Siws) were determined by colorimetry. The residual solid was weighed on the filter paper, followed by digestion with concentrated HNO3. The concentrations of the main cations and Pws, Siws in the digest liquid were measured by using the method mentioned above. After the supernatant was centrifuged, the precipitation was used to analyze the protein differences between the treatment groups and the control groups by 2-dimentional gel electrophoresis (2-DE). The experimental results showed that apatite and quartz were partially weathered, but kaolinite was dissolved completely. The population of bacteria increased when mineral powder was added in the liquid medium. Software analysis and comparison of the 2-DE pictures of bacterial proteins revealed 1134 visible protein spots in the treatment group, and 729 visible protein spots in the control group. To compare the bacterial protein expression contents of the treatment group with those of the control group, there were 496 different protein spots, including 214 protein spots which indicated that the protein contents increased, 75 protein spots were indicative of a decrease, and 207 proteins were newly synthesized. It is proposed that the increased bacterial contents may be related to some protein expression and activation

  17. Exploiting Bacterial Operons To Illuminate Human Iron-Sulfur Proteins.

    Science.gov (United States)

    Andreini, Claudia; Banci, Lucia; Rosato, Antonio

    2016-04-01

    Organisms from all kingdoms of life use iron-sulfur proteins (FeS-Ps) in a multitude of functional processes. We applied a bioinformatics approach to investigate the human portfolio of FeS-Ps. Sixty-one percent of human FeS-Ps bind Fe4S4 clusters, whereas 39% bind Fe2S2 clusters. However, this relative ratio varies significantly depending on the specific cellular compartment. We compared the portfolio of human FeS-Ps to 12 other eukaryotes and to about 700 prokaryotes. The comparative analysis of the organization of the prokaryotic homologues of human FeS-Ps within operons allowed us to reconstruct the human functional networks involving the conserved FeS-Ps common to prokaryotes and eukaryotes. These functional networks have been maintained during evolution and thus presumably represent fundamental cellular processes. The respiratory chain and the ISC machinery for FeS-P biogenesis are the two conserved processes that involve the majority of human FeS-Ps. Purine metabolism is another process including several FeS-Ps, in which BOLA proteins possibly have a regulatory role. The analysis of the co-occurrence of human FeS-Ps with other proteins highlighted numerous links between the iron-sulfur cluster machinery and the response mechanisms to cell damage, from repair to apoptosis. This relationship probably relates to the production of reactive oxygen species within the biogenesis and degradation of FeS-Ps.

  18. C21orf57 is a human homologue of bacterial YbeY proteins.

    Science.gov (United States)

    Ghosal, Anubrata; Köhrer, Caroline; Babu, Vignesh M P; Yamanaka, Kinrin; Davies, Bryan W; Jacob, Asha I; Ferullo, Daniel J; Gruber, Charley C; Vercruysse, Maarten; Walker, Graham C

    2017-03-11

    The product of the human C21orf57 (huYBEY) gene is predicted to be a homologue of the highly conserved YbeY proteins found in nearly all bacteria. We show that, like its bacterial and chloroplast counterparts, the HuYbeY protein is an RNase and that it retains sufficient function in common with bacterial YbeY proteins to partially suppress numerous aspects of the complex phenotype of an Escherichia coli ΔybeY mutant. Expression of HuYbeY in Saccharomyces cerevisiae, which lacks a YbeY homologue, results in a severe growth phenotype. This observation suggests that the function of HuYbeY in human cells is likely regulated through specific interactions with partner proteins similarly to the way YbeY is regulated in bacteria.

  19. The human-bacterial pathogen protein interaction networks of Bacillus anthracis, Francisella tularensis, and Yersinia pestis.

    Directory of Open Access Journals (Sweden)

    Matthew D Dyer

    Full Text Available BACKGROUND: Bacillus anthracis, Francisella tularensis, and Yersinia pestis are bacterial pathogens that can cause anthrax, lethal acute pneumonic disease, and bubonic plague, respectively, and are listed as NIAID Category A priority pathogens for possible use as biological weapons. However, the interactions between human proteins and proteins in these bacteria remain poorly characterized leading to an incomplete understanding of their pathogenesis and mechanisms of immune evasion. METHODOLOGY: In this study, we used a high-throughput yeast two-hybrid assay to identify physical interactions between human proteins and proteins from each of these three pathogens. From more than 250,000 screens performed, we identified 3,073 human-B. anthracis, 1,383 human-F. tularensis, and 4,059 human-Y. pestis protein-protein interactions including interactions involving 304 B. anthracis, 52 F. tularensis, and 330 Y. pestis proteins that are uncharacterized. Computational analysis revealed that pathogen proteins preferentially interact with human proteins that are hubs and bottlenecks in the human PPI network. In addition, we computed modules of human-pathogen PPIs that are conserved amongst the three networks. Functionally, such conserved modules reveal commonalities between how the different pathogens interact with crucial host pathways involved in inflammation and immunity. SIGNIFICANCE: These data constitute the first extensive protein interaction networks constructed for bacterial pathogens and their human hosts. This study provides novel insights into host-pathogen interactions.

  20. Insight into bacterial virulence mechanisms against host immune response via the Yersinia pestis-human protein-protein interaction network.

    Science.gov (United States)

    Yang, Huiying; Ke, Yuehua; Wang, Jian; Tan, Yafang; Myeni, Sebenzile K; Li, Dong; Shi, Qinghai; Yan, Yanfeng; Chen, Hui; Guo, Zhaobiao; Yuan, Yanzhi; Yang, Xiaoming; Yang, Ruifu; Du, Zongmin

    2011-11-01

    A Yersinia pestis-human protein interaction network is reported here to improve our understanding of its pathogenesis. Up to 204 interactions between 66 Y. pestis bait proteins and 109 human proteins were identified by yeast two-hybrid assay and then combined with 23 previously published interactions to construct a protein-protein interaction network. Topological analysis of the interaction network revealed that human proteins targeted by Y. pestis were significantly enriched in the proteins that are central in the human protein-protein interaction network. Analysis of this network showed that signaling pathways important for host immune responses were preferentially targeted by Y. pestis, including the pathways involved in focal adhesion, regulation of cytoskeleton, leukocyte transendoepithelial migration, and Toll-like receptor (TLR) and mitogen-activated protein kinase (MAPK) signaling. Cellular pathways targeted by Y. pestis are highly relevant to its pathogenesis. Interactions with host proteins involved in focal adhesion and cytoskeketon regulation pathways could account for resistance of Y. pestis to phagocytosis. Interference with TLR and MAPK signaling pathways by Y. pestis reflects common characteristics of pathogen-host interaction that bacterial pathogens have evolved to evade host innate immune response by interacting with proteins in those signaling pathways. Interestingly, a large portion of human proteins interacting with Y. pestis (16/109) also interacted with viral proteins (Epstein-Barr virus [EBV] and hepatitis C virus [HCV]), suggesting that viral and bacterial pathogens attack common cellular functions to facilitate infections. In addition, we identified vasodilator-stimulated phosphoprotein (VASP) as a novel interaction partner of YpkA and showed that YpkA could inhibit in vitro actin assembly mediated by VASP.

  1. Side effects of extra tRNA supplied in a typical bacterial protein production scenario

    DEFF Research Database (Denmark)

    Søgaard, Karina Marie; Nørholm, Morten H. H.

    2016-01-01

    Recombinant protein production is at the core of biotechnology and numerous molecular tools and bacterial strains have been developed to make the process more efficient. One commonly used generic solution is to supply extra copies of low-abundance tRNAs to compensate for the presence of complemen...

  2. Membrane composition influences the topology bias of bacterial integral membrane proteins.

    Science.gov (United States)

    Bay, Denice C; Turner, Raymond J

    2013-02-01

    Small multidrug resistance (SMR) protein family members confer bacterial resistance to toxic antiseptics and are believed to function as dual topology oligomers. If dual topology is essential for SMR activity, then the topology bias should change as bacterial membrane lipid compositions alter to maintain a "neutral" topology bias. To test this hypothesis, a bioinformatic analysis of bacterial SMR protein sequences was performed to determine a membrane protein topology based on charged amino acid residues within loops, and termini regions according to the positive inside rule. Three bacterial lipid membrane parameters were examined, providing the proportion of polar lipid head group charges at the membrane surface (PLH), the relative hydrophobic fatty acid length (FAL), and the proportion of fatty acid unsaturation (FAU). Our analysis indicates that individual SMR pairs, and to a lesser extent SMR singleton topology biases, are significantly correlated to increasing PLH, FAL and FAU differences validating the hypothesis. Correlations between the topology biases of SMR proteins identified in Gram+ compared to Gram- species and each lipid parameter demonstrated a linear inverse relationship.

  3. Bacterial mimetics of endocrine secretory granules as immobilized in vivo depots for functional protein drugs

    Science.gov (United States)

    Céspedes, María Virtudes; Fernández, Yolanda; Unzueta, Ugutz; Mendoza, Rosa; Seras-Franzoso, Joaquin; Sánchez-Chardi, Alejando; Álamo, Patricia; Toledo-Rubio, Verónica; Ferrer-Miralles, Neus; Vázquez, Esther; Schwartz, Simó; Abasolo, Ibane; Corchero, José Luis; Mangues, Ramon; Villaverde, Antonio

    2016-01-01

    In the human endocrine system many protein hormones including urotensin, glucagon, obestatin, bombesin and secretin, among others, are supplied from amyloidal secretory granules. These granules form part of the so called functional amyloids, which within the whole aggregome appear to be more abundant than formerly believed. Bacterial inclusion bodies (IBs) are non-toxic, nanostructured functional amyloids whose biological fabrication can be tailored to render materials with defined biophysical properties. Since under physiological conditions they steadily release their building block protein in a soluble and functional form, IBs are considered as mimetics of endocrine secretory granules. We have explored here if the in vivo implantation of functional IBs in a given tissue would represent a stable local source of functional protein. Upon intratumoral injection of bacterial IBs formed by a potent protein ligand of CXCR4 we have observed high stability and prevalence of the material in absence of toxicity, accompanied by apoptosis of CXCR4+ cells and tumor ablation. Then, the local immobilization of bacterial amyloids formed by therapeutic proteins in tumors or other tissues might represent a promising strategy for a sustained local delivery of protein drugs by mimicking the functional amyloidal architecture of the mammals’ endocrine system. PMID:27775083

  4. Bacterial collagen-like proteins that form triple-helical structures.

    Science.gov (United States)

    Yu, Zhuoxin; An, Bo; Ramshaw, John A M; Brodsky, Barbara

    2014-06-01

    A large number of collagen-like proteins have been identified in bacteria during the past 10years, principally from analysis of genome databases. These bacterial collagens share the distinctive Gly-Xaa-Yaa repeating amino acid sequence of animal collagens which underlies their unique triple-helical structure. A number of the bacterial collagens have been expressed in Escherichia coli, and they all adopt a triple-helix conformation. Unlike animal collagens, these bacterial proteins do not contain the post-translationally modified amino acid, hydroxyproline, which is known to stabilize the triple-helix structure and may promote self-assembly. Despite the absence of collagen hydroxylation, the triple-helix structures of the bacterial collagens studied exhibit a high thermal stability of 35-39°C, close to that seen for mammalian collagens. These bacterial collagens are readily produced in large quantities by recombinant methods, either in the original amino acid sequence or in genetically manipulated sequences. This new family of recombinant, easy to modify collagens could provide a novel system for investigating structural and functional motifs in animal collagens and could also form the basis of new biomedical materials with designed structural properties and functions.

  5. A method for in vivo identification of bacterial small RNA-binding proteins.

    Science.gov (United States)

    Osborne, Jonathan; Djapgne, Louise; Tran, Bao Quoc; Goo, Young Ah; Oglesby-Sherrouse, Amanda G

    2014-12-01

    Small bacterial regulatory RNAs (sRNAs) have gained immense appreciation over the last decade for their roles in mediating posttranscriptional gene regulation of numerous physiological processes. Several proteins contribute to sRNA stability and regulation, most notably the Hfq RNA-binding protein. However, not all sRNAs rely on Hfq for their stability. It is therefore likely that other proteins contribute to the stability and function of certain bacterial sRNAs. Here, we describe a methodology for identifying in vivo-binding proteins of sRNAs, developed using the iron-responsive PrrF and PrrH sRNAs of Pseudomonas aeruginosa. RNA was isolated from iron-depleted cultures, which were irradiated to cross-link nucleoprotein complexes. Subsequently, PrrF- and PrrH-protein complexes were enriched using cDNA "bait", and enriched RNA-protein complexes were analyzed by tandem mass spectrometry to identify PrrF and PrrH associated proteins. This method identified Hfq as a potential PrrF- and PrrH-binding protein. Interestingly, Hfq was identified more often in samples probed with the PrrF cDNA "bait" as compared to the PrrH cDNA "bait", suggesting Hfq has a stronger binding affinity for the PrrF sRNAs in vivo. Hfq binding to the PrrF and PrrH sRNAs was validated by electrophoretic mobility shift assays with purified Hfq protein from P. aeruginosa. As such, this study demonstrates that in vivo cross-linking coupled with sequence-specific affinity chromatography and tandem mass spectrometry (SSAC-MS/MS) is an effective methodology for unbiased identification of bacterial sRNA-binding proteins.

  6. 响应面优化含紫苏油粕高水分挤压蛋白工艺研究%Optimization of High Moisture Organized Technology of Perilla Oil Meal Protein Product by Design-Expert Design

    Institute of Scientific and Technical Information of China (English)

    田海娟; 朱珠; 张传智; 王成震

    2015-01-01

    Perilla oil meal and soy protein as a raw material, added wheat gluten, used the high moisture twin-screw extrusion technology, and through the single factor experiment and central composite rotary design to determine the optimal process of Perilla oil meal protein products. The results showed that Perilla oil meal addition was the biggest effected on quality of protein products , followed by extruding temperature and material moisture content. The optimal process parameters were Perilla oil meal addition 10%, moisture content 50%, extrusion temperature 130℃.%以紫苏油粕和大豆蛋白为原料,并加入谷朊粉,采用双螺杆挤压技术,通过单因素试验和中心旋转组合试验确定高水分挤压组织化的植物蛋白产品最优工艺.结果表明,紫苏油粕加入量对高水分挤压蛋白质构与感官品质影响较大,含紫苏油粕高水分挤压组织蛋白产品最佳工艺条件:紫苏油粕10%、物料水分含量50%、挤压温度130℃.

  7. The innate immune protein Nod2 binds directly to MDP, a bacterial cell wall fragment.

    Science.gov (United States)

    Grimes, Catherine Leimkuhler; Ariyananda, Lushanti De Zoysa; Melnyk, James E; O'Shea, Erin K

    2012-08-22

    Mammalian Nod2 is an intracellular protein that is implicated in the innate immune response to the bacterial cell wall and is associated with the development of Crohn's disease, Blau syndrome, and gastrointestinal cancers. Nod2 is required for an immune response to muramyl dipeptide (MDP), an immunostimulatory fragment of bacterial cell wall, but it is not known whether MDP binds directly to Nod2. We report the expression and purification of human Nod2 from insect cells. Using novel MDP self-assembled monolayers (SAMs), we provide the first biochemical evidence for a direct, high-affinity interaction between Nod2 and MDP.

  8. Jun N-Terminal Protein Kinase Enhances Middle Ear Mucosal Proliferation during Bacterial Otitis Media▿

    Science.gov (United States)

    Furukawa, Masayuki; Ebmeyer, Jörg; Pak, Kwang; Austin, Darrell A.; Melhus, Åsa; Webster, Nicholas J. G.; Ryan, Allen F.

    2007-01-01

    Mucosal hyperplasia is a characteristic component of otitis media. The present study investigated the participation of signaling via the Jun N-terminal protein kinase (JNK) mitogen-activated protein kinase in middle ear mucosal hyperplasia in animal models of bacterial otitis media. Otitis media was induced by the inoculation of nontypeable Haemophilus influenzae into the middle ear cavity. Western blotting revealed that phosphorylation of JNK isoforms in the middle ear mucosa preceded but paralleled mucosal hyperplasia in this in vivo rat model. Nuclear JNK phosphorylation was observed in many cells of both the mucosal epithelium and stroma by immunohistochemistry. In an in vitro model of primary rat middle ear mucosal explants, bacterially induced mucosal growth was blocked by the Rac/Cdc42 inhibitor Clostridium difficile toxin B, the mixed-lineage kinase inhibitor CEP11004, and the JNK inhibitor SP600125. Finally, the JNK inhibitor SP600125 significantly inhibited mucosal hyperplasia during in vivo bacterial otitis media in guinea pigs. Inhibition of JNK in vivo resulted in a diminished proliferative response, as shown by a local decrease in proliferating cell nuclear antigen protein expression by immunohistochemistry. We conclude that activation of JNK is a critical pathway for bacterially induced mucosal hyperplasia during otitis media, influencing tissue proliferation. PMID:17325051

  9. Dissecting the specificity of protein-protein interaction in bacterial two-component signaling: orphans and crosstalks.

    Directory of Open Access Journals (Sweden)

    Andrea Procaccini

    Full Text Available Predictive understanding of the myriads of signal transduction pathways in a cell is an outstanding challenge of systems biology. Such pathways are primarily mediated by specific but transient protein-protein interactions, which are difficult to study experimentally. In this study, we dissect the specificity of protein-protein interactions governing two-component signaling (TCS systems ubiquitously used in bacteria. Exploiting the large number of sequenced bacterial genomes and an operon structure which packages many pairs of interacting TCS proteins together, we developed a computational approach to extract a molecular interaction code capturing the preferences of a small but critical number of directly interacting residue pairs. This code is found to reflect physical interaction mechanisms, with the strongest signal coming from charged amino acids. It is used to predict the specificity of TCS interaction: Our results compare favorably to most available experimental results, including the prediction of 7 (out of 8 known interaction partners of orphan signaling proteins in Caulobacter crescentus. Surveying among the available bacterial genomes, our results suggest 15∼25% of the TCS proteins could participate in out-of-operon "crosstalks". Additionally, we predict clusters of crosstalking candidates, expanding from the anecdotally known examples in model organisms. The tools and results presented here can be used to guide experimental studies towards a system-level understanding of two-component signaling.

  10. Learning through school meals?

    DEFF Research Database (Denmark)

    Benn, Jette; Carlsson, Monica Susanne

    2014-01-01

    individual and focus Group interviws were conducted with students in grade 5-7 and grades 8-9- Furthermor, students were obserede during lunch breaks, and interviews were conducted with the class teacher, headmaster and/or the person responsible for school meals. The pupose of the article is to explore...... the lelarning potentials of school meals. The corss-case analysis focuses on the involved actors' perceptions of the school meal project and the meals, including Places Places, times and contexts, and the pupils' concepts and competencies in relation to food, meals and Health, as well as their involvement...... of dilemmas, such as whether the lunch break should be a part of or a break from education, are school meals a common (school) or private (parent) responsibility, and questions about pupils' and teachers' roles and participation in school meals....

  11. Predicting gram-positive bacterial protein subcellular localization based on localization motifs.

    Science.gov (United States)

    Hu, Yinxia; Li, Tonghua; Sun, Jiangming; Tang, Shengnan; Xiong, Wenwei; Li, Dapeng; Chen, Guanyan; Cong, Peisheng

    2012-09-07

    The subcellular localization of proteins is closely related to their functions. In this work, we propose a novel approach based on localization motifs to improve the accuracy of predicting subcellular localization of Gram-positive bacterial proteins. Our approach performed well on a five-fold cross validation with an overall success rate of 89.5%. Besides, the overall success rate of an independent testing dataset was 97.7%. Moreover, our approach was tested using a new experimentally-determined set of Gram-positive bacteria proteins and achieved an overall success rate of 96.3%.

  12. Iron dialyzability from hospital duplicate meals: daily intake.

    Science.gov (United States)

    Velasco-Reynold, Carlos; Navarro-Alarcon, Miguel; Lopez-Ga de la Serrana, Herminia; Perez-Valero, Vidal; Lopez-Martinez, María C

    2009-09-01

    Both total and dialyzable iron levels and corresponding dialyzability were determined in 108 duplicate meals during 36 consecutive days. Total mean iron fraction of 5.90 +/- 4.97 mg was found in the meals. The iron supplied by the meals is directly and significantly (p < 0.05) correlated with macromicronutrient content (carbohydrates, fiber, and protein). The mean iron dialyzability (4.81 +/- 3.25%) was low and not significantly different among the three primary meals (breakfast, lunch, and dinner). Significant interactions of several minerals on iron levels were found (p < 0.05). Iron dialyzability was only statistically influenced by zinc dialyzability in meals (p < 0.05). The dialyzed iron fraction present in meals was significantly correlated with protein and ascorbic acid levels (p < 0.01). The mean iron daily dietary intake was 17.7 +/- 6.91 mg. The hospital meals provided enough iron. Foods of animal origin are primary sources of iron in diet.

  13. 月见草籽粕分离蛋白的制备%Study on preparation of protein isolation from primrose meal

    Institute of Scientific and Technical Information of China (English)

    马涛; 吕品

    2009-01-01

    Based on primrose meal, the process conditions and functional properties of protein isolated was prepared on alkali-extraction and acid-isolation.Through orthogonal tests,the best conditions of extraction were: the pH 12,the temperature 45℃, the times of extraction 3, the proportion of the material to liquid 1:12, 1:10, 1:8 respectively and protein deposited at pH6.0, pH3.8.In the product gained through spray drying process the content were 75.5%.%以月见草冷榨浸出粕为材料,初步探索碱提酸沉法制备月见草籽粕分离蛋白的工艺条件及其功能特性通过正交实验得到提取的最佳工艺条件为:pH12,温度45℃,提取3次,料液比分别1:12、1:10、1:8;调pH6.0、3.8二次沉淀,喷雾干燥后产品的粗蛋白含量达75.5%.

  14. Upregulation of the immune protein gene hemolin in the epidermis during the wandering larval stage of the Indian meal moth, Plodia interpunctella.

    Science.gov (United States)

    Aye, Tin Tin; Shim, Jae-Kyoung; Rhee, In-Koo; Lee, Kyeong-Yeoll

    2008-08-01

    Expression of hemolin, which generates an immune protein, was up-regulated in wandering fifth instar larval stage of Plodia interpunctella. The mRNA level peaked in the middle of the wandering stage. Major expression was in the epidermis, rather than in the fat body or gut. To test a possible ecdysteroid effect on hemolin induction we treated with RH-5992, an ecdysteroid agonist, and KK-42, which inhibits ecdysteroid biosynthesis in both feeding and wandering fifth instar larvae. When feeding larvae were treated with RH-5992 the hemolin mRNA level was increased. When wandering larvae were treated with KK-42 its level was reduced. In addition, when KK-42-treated larvae were subsequently treated with RH-5992 the hemolin mRNA level was recovered. These results strongly suggest that ecdysteroid up-regulates the expression of hemolin mRNA. Hormonal and bacterial effects on hemolin induction were further analyzed at the tissue level. Major induction of hemolin mRNA was detected following both RH-5992 treatment and bacterial injection in the epidermis of both feeding and wandering larvae. Minor induction of hemolin was detected in the fat body following a bacterial injection, but not RH-5992 treatment. We infer that in P. interpunctella larvae, the epidermis is the major tissue for hemolin induction in naïve insects and in insects manipulated with bacterial and hormonal treatments.

  15. Phase variation of Opa proteins of Neisseria meningitidis and the effects of bacterial transformation

    Indian Academy of Sciences (India)

    Manish Sadarangani; J Claire Hoe; Katherine Makepeace; Peter Van Der Ley; Andrew J Pollard

    2016-03-01

    Opa proteins are major proteins involved in meningococcal colonization of the nasopharynx and immune interactions. Opa proteins undergo phase variation (PV) due to the presence of the 5′-CTCTT-3′ coding repeat (CR) sequence. The dynamics of PV of meningococcal Opa proteins is unknown. Opa PV, including the effect of transformation on PV, was assessed using a panel of Opa-deficient strains of Neisseria meningitidis. Analysis of Opa expression from UK disease-causing isolates was undertaken. Different opagenes demonstrated variable rates of PV, between 6.4 ×10–4 and 6.9 ×10–3 per cell per generation. opa genes with a longer CR tract had a higher rate of PV (r2=0.77, p=0.1212). Bacterial transformation resulted in a 180-fold increase in PV rate. The majority of opagenes in UK disease isolates (315/463, 68.0%) were in the ‘on’ phase, suggesting the importance of Opa proteins during invasive disease. These data provide valuable information for the first time regarding meningococcal Opa PV. The presence of Opa PV in meningococcal populations and high expression of Opa among invasive strains likely indicates the importance of this protein in bacterial colonization in the human nasopharynx. These findings have potential implications for development of vaccines derived from meningococcal outer membranes.

  16. Brillouin spectroscopy as a new method of screening for increased CSF total protein during bacterial meningitis.

    Science.gov (United States)

    Steelman, Zachary; Meng, Zhaokai; Traverso, Andrew J; Yakovlev, Vladislav V

    2015-05-01

    Bacterial meningitis is a disease of pronounced clinical significance, especially in the developing world. Immediate treatment with antibiotics is essential, and no single test can provide a conclusive diagnosis. It is well established that elevated total protein in cerebrospinal fluid (CSF) is associated with bacterial meningitis. Brillouin spectroscopy is a widely used optical technique for noninvasive determination of the elastic moduli of materials. We found that elevated protein levels in CSF alter the fluid elasticity sufficiently to be measurable by Brillouin spectroscopy, with model healthy and diseased fluids distinguishable to marked significance (P = 0.014), which increases with sample concentration by dialysis. Typical raw output of a 2-stage VIPA Brillouin spectrometer: inelastically scattered Brillouin peaks (arrows) and elastically scattered incident radiation (center cross).

  17. Substituição da farinha de carne suína por fontes vegetais em dietas para carpa-húngara Replacement of pork meal by plant protein sources in Hungarian carp diets

    Directory of Open Access Journals (Sweden)

    Giovani Taffarel Bergamin

    2010-10-01

    Full Text Available O objetivo deste trabalho foi avaliar o crescimento e a qualidade de carcaça de carpa-húngara alimentada com dietas em que houve substituição da farinha de carne suína por farelos de soja e canola, bem como determinar parâmetros bioquímicos do metabolismo dos peixes e a qualidade sensorial do filé. Cada um dos farelos contribuiu com 50% da proteína na mistura. Cinco dietas foram avaliadas, com níveis de substituição (0, 25, 50, 75 e 100% da proteína da farinha de carne suína pela mistura das fontes vegetais. A inclusão de fontes proteicas vegetais nas dietas reduziu o crescimento, a deposição de gordura corporal e no filé, e o colesterol total dos peixes. A cor e o sabor dos filés não foram afetados pela inclusão das fontes proteicas vegetais. A dieta à base de farinha de carne suína é mais eficiente para o crescimento da carpa-húngara, e proporciona maior deposição de proteína no peixe inteiro e no filé.The objective of this work was to evaluate growth and carcass composition of Hungarian carp fed with diets in which pork meat meal was replaced by a combination of canola and soybean meals, as well as to determine fish metabolism biochemical parameters and the sensorial quality of the fillet. Each plant meal contributed with 50% of the dietary protein of the mixture. Five diets were tested, with replacement levels of 0, 25, 50, 75 and 100% of pork meal by plant protein sources. The inclusion of the plant-protein meal in the diet results in lower overall growth, lower body and fillet lipid deposition and lower total cholesterol of the fish. Color and flavor of the fillets were not affected by inclusion of plant protein sources. A pork meat meal based diet is more efficient for Hungarian carp growth, and provides higher whole fish and fillet protein deposition.

  18. Identification of a novel bacterial outer membrane interleukin-1Β-binding protein from Aggregatibacter actinomycetemcomitans.

    Directory of Open Access Journals (Sweden)

    Annamari Paino

    Full Text Available Aggregatibacter actinomycetemcomitans is a gram-negative opportunistic oral pathogen. It is frequently associated with subgingival biofilms of both chronic and aggressive periodontitis, and the diseased sites of the periodontium exhibit increased levels of the proinflammatory mediator interleukin (IL-1β. Some bacterial species can alter their physiological properties as a result of sensing IL-1β. We have recently shown that this cytokine localizes to the cytoplasm of A. actinomycetemcomitans in co-cultures with organotypic gingival mucosa. However, current knowledge about the mechanism underlying bacterial IL-1β sensing is still limited. In this study, we characterized the interaction of A. actinomycetemcomitans total membrane protein with IL-1β through electrophoretic mobility shift assays. The interacting protein, which we have designated bacterial interleukin receptor I (BilRI, was identified through mass spectrometry and was found to be Pasteurellaceae specific. Based on the results obtained using protein function prediction tools, this protein localizes to the outer membrane and contains a typical lipoprotein signal sequence. All six tested biofilm cultures of clinical A. actinomycetemcomitans strains expressed the protein according to phage display-derived antibody detection. Moreover, proteinase K treatment of whole A. actinomycetemcomitans cells eliminated BilRI forms that were outer membrane specific, as determined through immunoblotting. The protein was overexpressed in Escherichia coli in both the outer membrane-associated form and a soluble cytoplasmic form. When assessed using flow cytometry, the BilRI-overexpressing E. coli cells were observed to bind 2.5 times more biotinylated-IL-1β than the control cells, as detected with avidin-FITC. Overexpression of BilRI did not cause binding of a biotinylated negative control protein. In a microplate assay, soluble BilRI bound to IL-1β, but this binding was not specific, as a control

  19. Substituição da proteína do farelo de soja pela proteína do glúten de milho em rações para alevinos de tilápia do Nilo - DOI: 10.4025/actascianimsci.v25i2.1991 Replacement of soybean meal protein by corn gluten meal protein in diets for Nile tilapia fingerlings - DOI: 10.4025/actascianimsci.v25i2.1991

    Directory of Open Access Journals (Sweden)

    Jeisson Emerson Casimiro Ferrari

    2003-04-01

    Full Text Available O experimento foi conduzido com o objetivo de avaliar a substituição da proteína do farelo de soja pela proteína do glúten de milho em rações para alevinos de tilápia do Nilo, Oreochromis niloticus L. (Cichlidae. O delineamento experimental foi inteiramente casualizado com 5 tratamentos 0%; 25%; 50%; 75% e 100% de substituição da proteína do farelo de soja pela proteína do glúten de milho e, com 4 repetições. Os níveis adotados corresponderam a 11,75%; 23%; 35,78% e 47,28% de inclusão de glúten de milho nas rações, as quais foram formuladas para serem isoprotéicas em proteína digestível (PD, isocalóricas em energia digestível (ED e com a mesma quantidade de fibra bruta, lisina e metionina. Foram utilizados 100 alevinos com peso médio de 7,47±1,61g, distribuídos em 20 aquários (250L, em sistema de recirculação de água dotado de controle de temperatura. Foi observado efeito quadrático para o ganho de peso, conversão alimentar e taxa de eficiência protéica, sendo os respectivos valores ótimos estimados em 30,69%; 48% e 46,25% de substituição da proteína do farelo de soja pela proteína do glúten de milho e, para o consumo de ração, foi verificado efeito linear. Em função da média referente aos valores estimados para os diferentes parâmetros avaliados, pôde-se concluir que a proteína do glúten de milho pode substituir até 42% (19,82% de inclusão na ração da proteína do farelo de soja em rações para alevinos de tilápia do Nilo.The research was carried out aiming to evaluate the replacement of soybean meal protein by corn gluten meal protein in Nile tilapia, Oreochromis niloticus L. (Cichlidae diets. The experimental design was completely randomized with five treatments 0%, 25%, 50%, 75% and 100% of replacement of soybean protein by corn gluten meal protein and 4 replicates. The used levels corresponded to 11.75%, 23%, 35.78% and 42.28% of corn gluten meal inclusion in diets, formulated to be

  20. Comparison of amino acid digestibility coefficients for soybean meal, canola meal, fish meal, and meat and bone meal among 3 different bioassays.

    Science.gov (United States)

    Kim, E J; Utterback, P L; Parsons, C M

    2012-06-01

    The objective of this study was to determine amino acid digestibility of 4 feedstuffs [soybean meal (SBM), canola meal, fish meal, and meat and bone meal (MBM)] using the precision-fed cecectomized rooster assay (PFR), the standardized ileal assay (SIAAD), and a newly developed precision-fed ileal broiler assay (PFC). For the PFR, cecectomized roosters were precision-fed approximately 30 g of feed sample, and excreta were collected 48 h postfeeding. For the SIAAD, 16-d-old broilers were fed a semipurified diet containing the feed samples as the only source of protein from 17 to 21 d, with ileal digesta collected at 21 d. For the PFC, 22-d-old broilers were precision-fed 10 g of feed sample mixed with chromic oxide, and ileal digesta were collected at 4 h postfeeding. Digestibility coefficients were standardized using a nitrogen-free diet for the SIAAD and PFC and using fasted roosters for the PFR. There were generally no consistent differences in standardized amino acid digestibility values among assays, and values were in general agreement among assays, particularly for SBM and MBM. Differences did occur among methods for amino acid digestibility in fish meal; however, these differences were not consistent among methods or amino acids. The results of the study indicated that all 3 bioassays are acceptable for determining the amino acid digestibility of SBM, canola meal, MBM, and fish meal for poultry.

  1. Reconstitution of a nanomachine driving the assembly of proteins into bacterial outer membranes

    Science.gov (United States)

    Shen, Hsin-Hui; Belousoff, Matthew J.; Noinaj, Nicholas; Lu, Jingxiong; Holt, Stephen A.; Tan, Khershing; Selkrig, Joel; Webb, Chaille T.; Buchanan, Susan K.; Martin, Lisandra L.; Lithgow, Trevor

    2015-01-01

    In biological membranes, various protein secretion devices function as nanomachines, and measuring the internal movements of their component parts is a major technological challenge. The translocation assembly module (the TAM) is a nanomachine required for virulence of bacterial pathogens. We have reconstituted a membrane containing the TAM onto a gold surface for characterization by Quartz Crystal Microbalance with Dissipation (QCM-D) and Magnetic Contrast Neutron Reflectrometry (MCNR). The MCNR studies provided structural resolution down to 1Å, enabling accurate measurement of protein domains projecting from the membrane layer. Here, we show that dynamic movements within the TamA component of the TAM are initiated in the presence of a substrate protein, Ag43, and that these movements recapitulate an initial stage in membrane protein assembly. The reconstituted system provides a powerful new means to study molecular movements in biological membranes, and the technology is widely applicable to studying the dynamics of diverse cellular nanomachines. PMID:25341963

  2. Optimizing protein and energy intake in hospitals by improving individualized meal serving, hosting and the eating environment

    DEFF Research Database (Denmark)

    Holst, Mette; Beermann, Tina; Mortensen, Marie Nerup

    2017-01-01

    OBJECTIVE: Optimizing protein and energy intake by food in nutritional risk patients is difficult. The aim of this study was to improve the ≥75% of energy and protein requirements. We would like to see nurses take on the role of hosting the nutritional-risk patients, including focusing on bringing...... for eating. RESULTS: The study comprised 76 24-h FRs at baseline and 108 FRs at follow-up. The total group had improved food intake; 75% of individual energy requirements were met by (67.6% vs. 40%; P = 0.036) and the Heart-Lung Surgery group (85.7 vs. 38.5; P = 0.036). This was not reflected for protein (NS...... seen in two of the three departments and in the overall group, and no statistical or clinically significant improvements to protein intake were observed. The relative risk of meeting 75% of energy requirements was improved in the overall group and in patients in the Department of Heart-Lung Surgery...

  3. A review of canola meal as an alternative feed ingredient for ducks.

    Science.gov (United States)

    Wickramasuriya, Samiru Sudharaka; Yi, Young-Joo; Yoo, Jaehong; Kang, Nam Kyu; Heo, Jung Min

    2015-01-01

    This review provides an overview of the published data on the canola meal and its suitability for duck as an alternative plant-origin protein source to soybean meal. Canola meal is a legume origin protein source containing comparable amino acid profile to soybean meal and rich in essential minerals and vitamins. Nonetheless, it is known to contain less in energy content than soybean meal. Factors like field conditions and processing methods creates compositional variations among canola meal. Presence of anti-nutritional factors such as phenolic substances, phytate and glucosinolates which are known to reduce growth performance in livestock animals, are the major drawbacks for canola meal to be a competitive plant-origin protein source in the feed industry. This review is focused to address i) nutritional characteristics and feeding value of canola meal for ducks and ii) impacts of feeding canola meal on performances of ducks.

  4. STUDIES ON THE BACTERIOPHAGE OF D'HERELLE : IX. EVIDENCE OF HYDROLYSIS OF BACTERIAL PROTEIN DURING LYSIS.

    Science.gov (United States)

    Hetler, D M; Bronfenbrenner, J

    1928-07-31

    1. During the process of lysis by bacteriophage, there is an appreciable increase in the amount of free amino acid present in the culture. 2. The increase of free amino acid is due to hydrolysis of bacterial protein.

  5. The oral immunogenicity of BioProtein, a bacterial single-cell protein, is affected by its particulate nature

    DEFF Research Database (Denmark)

    Christensen, Hanne Risager; Larsen, L.C.; Frøkiær, Hanne

    2003-01-01

    The bacterial single-cell protein BioProtein (BP; Norferm Danmark, Odense, Denmark), produced by fermentation of natural gas with methanotrophic bacteria, is a potential protein source for man and animals. For human consumption, removal of the nucleic acid is necessary. Preliminary studies have...... shown that ingested BP induces a specific immune response. The objective of the present study was to characterize the type of response, its development over time and product-related causative factors. Mice were fed with diets containing 60 g nucleic acid-reduced BP/kg, 240 g nucleic acid-reduced BP...... and saliva. Ingested BP induced a steady specific mucosal and systemic immune response, characterized by a dose-dependent production of immunoglobulin and immunoglobulin A in blood and immunoglobulin A in saliva. Basic BP and nucleic acid-reduced BP induced identical responses. However, feeding mice BP...

  6. Replacing moringa leaf (Moringa oleifera partially by protein replacement in soybean meal of fancy carp (Cyprinus carpio

    Directory of Open Access Journals (Sweden)

    Bundit Yuangsoi

    2012-11-01

    Full Text Available Moringa oleifera Lam (Moringaceae is a highly valued plant, distributed in many countries of the tropics and subtropics.The leaves are the protein source with an adequate profile of amino acids. The present study was undertaken in orderto determine the effect of a dietary of moringa leaves on digestibility and growth performance of fancy carp. Fish were fedwith diets containing isonitrogenouse and isoenergetic formulated by 20 and 50 g kg-1 of moringa leaves to replace protein insoybean. Fish were distributed in 500-liter tanks with flow-through water. Every fish was weighed and after the terminalexperiment, all groups’ livers and distal intestines were sampled. All fish grew normally (p>0.05 but fish fed with proteinreplacingmoringa leaves at 50 g kg-1 were noted to exhibit slightly poor growth performance and feed utilization. The studyindicated that the tested moringa leaf diet contains ingredients that could be used for fancy carp diets with possibly notover up to 20 g kg-1 soybean protein replacement without negative effect on growth and digestibility.

  7. Targeting Bacterial Dsb Proteins for the Development of Anti-Virulence Agents.

    Science.gov (United States)

    Smith, Roxanne P; Paxman, Jason J; Scanlon, Martin J; Heras, Begoña

    2016-07-16

    Recent years have witnessed a dramatic increase in bacterial antimicrobial resistance and a decline in the development of novel antibiotics. New therapeutic strategies are urgently needed to combat the growing threat posed by multidrug resistant bacterial infections. The Dsb disulfide bond forming pathways are potential targets for the development of antimicrobial agents because they play a central role in bacterial pathogenesis. In particular, the DsbA/DsbB system catalyses disulfide bond formation in a wide array of virulence factors, which are essential for many pathogens to establish infections and cause disease. These redox enzymes are well placed as antimicrobial targets because they are taxonomically widespread, share low sequence identity with human proteins, and many years of basic research have provided a deep molecular understanding of these systems in bacteria. In this review, we discuss disulfide bond catalytic pathways in bacteria and their significance in pathogenesis. We also review the use of different approaches to develop inhibitors against Dsb proteins as potential anti-virulence agents, including fragment-based drug discovery, high-throughput screening and other structure-based drug discovery methods.

  8. A dynamin-like protein involved in bacterial cell membrane surveillance under environmental stress.

    Science.gov (United States)

    Sawant, Prachi; Eissenberger, Kristina; Karier, Laurence; Mascher, Thorsten; Bramkamp, Marc

    2016-09-01

    In ever-changing natural environments, bacteria are continuously challenged with numerous biotic and abiotic stresses. Accordingly, they have evolved both specific and more general mechanisms to counteract stress-induced damage and ensure survival. In the soil habitat of Bacillus subtilis, peptide antibiotics and bacteriophages are among the primary stressors that affect the integrity of the cytoplasmic membrane. Dynamin-like proteins (DLPs) play a major role in eukaryotic membrane re-modelling processes, including antiviral activities, but the function of the corresponding bacterial homologues was so far poorly understood. Here, we report on the protective function of a bacterial DLP, DynA from B. subtilis. We provide evidence that DynA plays an important role in a membrane surveillance system that counteracts membrane pore formation provoked by antibiotics and phages. In unstressed cells, DynA is a highly dynamic membrane-associated protein. Upon membrane damage, DynA localizes into large and static assemblies, where DynA acts locally to counteract stress-induced pores, presumably by inducing lipid bilayer fusion and sealing membrane gaps. Thus, lack of DynA increases the sensitivity to antibiotic exposure and phage infection. Taken together, our work suggests that DynA, and potentially other bacterial DLPs, contribute to the innate immunity of bacteria against membrane stress.

  9. The pneumococcal serine-rich repeat protein is an intra-species bacterial adhesin that promotes bacterial aggregation in vivo and in biofilms.

    NARCIS (Netherlands)

    Sanchez, C.J.; Shivshankar, P.; Stol, K.; Trakhtenbroit, S.; Sullam, P.M.; Sauer, K.; Hermans, P.W.M.; Orihuela, C.J.

    2010-01-01

    The Pneumococcal serine-rich repeat protein (PsrP) is a pathogenicity island encoded adhesin that has been positively correlated with the ability of Streptococcus pneumoniae to cause invasive disease. Previous studies have shown that PsrP mediates bacterial attachment to Keratin 10 (K10) on the surf

  10. Biophysical analysis of the interaction of the serum protein human β2GPI with bacterial lipopolysaccharide

    Directory of Open Access Journals (Sweden)

    Anna Gries

    2014-01-01

    Full Text Available There are several human serum proteins for which no clear role is yet known. Among these is the abundant serum protein beta2-glycoprotein-I (β2GPI, which is known to bind to negatively charged phospholipids as well as to bacterial lipopolysaccharides (LPS, and was therefore proposed to play a role in the immune response. To understand the details of these interactions, a biophysical analysis of the binding of β2GPI to LPS and phosphatidylserine (PS was performed. The data indicate only a moderate tendency of the protein (1 to influence the LPS-induced cytokine production in vitro, (2 to react exothermally with LPS in a non-saturable way, and (3 to change its local microenvironment upon LPS association. Additionally, we found that the protein binds more strongly to phosphatidylserine (PS than to LPS. Furthermore, β2GPI converts the LPS bilayer aggregates into a stronger multilamellar form, and reduces the fluidity of the hydrocarbon moiety of LPS due to a rigidification of the acyl chains. From these data it can be concluded that β2GPI plays a role as an immune-modulating agent, but there is much less evidence for a role in immune defense against bacterial toxins such as LPS.

  11. Super-Resolution Microscopy and Tracking of DNA-Binding Proteins in Bacterial Cells

    Science.gov (United States)

    Uphoff, Stephan

    2016-01-01

    Summary The ability to detect individual fluorescent molecules inside living cells has enabled a range of powerful microscopy techniques that resolve biological processes on the molecular scale. These methods have also transformed the study of bacterial cell biology, which was previously obstructed by the limited spatial resolution of conventional microscopy. In the case of DNA-binding proteins, super-resolution microscopy can visualize the detailed spatial organization of DNA replication, transcription, and repair processes by reconstructing a map of single-molecule localizations. Furthermore, DNA binding activities can be observed directly by tracking protein movement in real time. This allows identifying subpopulations of DNA-bound and diffusing proteins, and can be used to measure DNA-binding times in vivo. This chapter provides a detailed protocol for super-resolution microscopy and tracking of DNA-binding proteins in Escherichia coli cells. The protocol covers the construction of cell strains and describes data acquisition and analysis procedures, such as super-resolution image reconstruction, mapping single-molecule tracks, computing diffusion coefficients to identify molecular subpopulations with different mobility, and analysis of DNA-binding kinetics. While the focus is on the study of bacterial chromosome biology, these approaches are generally applicable to other molecular processes and cell types. PMID:27283312

  12. Structural basis for the reversible activation of a Rho protein by the bacterial toxin SopE

    OpenAIRE

    Buchwald, Gretel; Friebel, Andrea; Galán, Jorge E.; Hardt, Wolf-Dietrich; Wittinghofer, Alfred; Scheffzek, Klaus

    2002-01-01

    The bacterial enteropathogen Salmonella typhimurium employs a type III secretion system to inject bacterial toxins into the host cell cytosol. These toxins transiently activate Rho family GTP-binding protein-dependent signaling cascades to induce cytoskeletal rearrangements. One of these translocated Salmonella toxins, SopE, can activate Cdc42 in a Dbl-like fashion despite its lack of sequence similarity to Dbl-like proteins, the Rho-specific eukaryotic guanine nucleotide exchange factors. To...

  13. quality of broiler fed diet supplemented by garlic meal and white turmeric meal

    Directory of Open Access Journals (Sweden)

    Nanung Danar Dono

    2010-06-01

    Full Text Available This research was done within 42 days to investigate the effect of diet supplemented by garlic (Allium sativum and white turmeric (Curcuma xanthorrhiza Roxb meals on physical and chemical quality of broiler meat. The number of 90 broiler DOC were used in this study. They were randomly allocated into 18 unit of cages. During the study, the chicken were given 6 feeding treatments, i.e.: R-0 (98.0% base diet + 2.0% filler; as control diet, RB-1 (98.0% base diet + 1.0% garlic meal + 1.0% filler, RB-2 (98.0% base diet + 2.0% garlic meal, RT-1 (98.0% base diet + 1.0% white turmeric meal + 1.0% filler, RT-2 (98.0% base diet + 2.0% white turmeric meal, and RB1T1 (98.0% base diet + 1.0% garlic meal + 1.0% white turmeric meal. The base diet was composed of: yellow corn, soybean meal, fish meal, rice polishing meal, sorghum, poultry meat meal, mineral mix, and was design to contain 17.5% crude protein and metabolizable energy 2,900 kcal/kg. Variables observed were: physical appearance (slaughter weight, non-feather weight, carcass weight, physical quality (pH, water holding capacity, cooking lose, tenderness, and cholesterol content (breast meat and blood cholesterol. All data were statistically analyzed by the Oneway of ANOVA and followed by the DMRT for significant results. Results showed that 1.0 - 2.0% garlic meal and 1.0 - 2.0% white turmeric meal supplementation reduced: breast meat cholesterol (P < 0.05, cooking lose (P < 0.05, and increased: pH (P < 0.01, and water holding capacity (P < 0.01 and improved tenderness (P < 0.05. Supplementation of 2% garlic meal and white turmeric meal didn’t affect slaughter weight, non-feather weight, carcass weight, nor blood cholesterol.

  14. The r1162 mob proteins can promote conjugative transfer from cryptic origins in the bacterial chromosome.

    Science.gov (United States)

    Meyer, Richard

    2009-03-01

    The mobilization proteins of the broad-host-range plasmid R1162 can initiate conjugative transfer of a plasmid from a 19-bp locus that is partially degenerate in sequence. Such loci are likely to appear by chance in the bacterial chromosome and could act as cryptic sites for transfer of chromosomal DNA when R1162 is present. The R1162-dependent transfer of chromosomal DNA, initiated from one such potential site in Pectobacterium atrosepticum, is shown here. A second active site was identified in Escherichia coli, where it is also shown that large amounts of DNA are transferred. This transfer probably reflects the combined activity of the multiple cryptic origins in the chromosome. Transfer of chromosomal DNA due to the presence of a plasmid in the cytoplasm describes a previously unrecognized potential for the exchange of bacterial DNA.

  15. Mutations in the bacterial ribosomal protein l3 and their association with antibiotic resistance

    DEFF Research Database (Denmark)

    Klitgaard, Rasmus N; Ntokou, Eleni; Nørgaard, Katrine

    2015-01-01

    Different groups of antibiotics bind to the peptidyl transferase center (PTC) in the large subunit of the bacterial ribosome. Resistance to these groups of antibiotics has often been linked with mutations or methylations of the 23S rRNA. In recent years, there has been a rise in the number...... of studies where mutations have been found in the ribosomal protein L3 in bacterial strains resistant to PTC-targeting antibiotics but there is often no evidence that these mutations actually confer antibiotic resistance. In this study, a plasmid exchange system was used to replace plasmid-carried wild...... background. Ten plasmid-carried mutated L3 genes were constructed, and their effect on growth and antibiotic susceptibility was investigated. Additionally, computational modeling of the impact of L3 mutations in E. coli was used to assess changes in 50S structure and antibiotic binding. All mutations...

  16. Dissecting the ATP hydrolysis pathway of bacterial enhancer-binding proteins.

    Science.gov (United States)

    Bose, Daniel; Joly, Nicolas; Pape, Tillmann; Rappas, Mathieu; Schumacher, Jorg; Buck, Martin; Zhang, Xiaodong

    2008-02-01

    bEBPs (bacterial enhancer-binding proteins) are AAA+ (ATPase associated with various cellular activities) transcription activators that activate gene transcription through a specific bacterial sigma factor, sigma(54). Sigma(54)-RNAP (RNA polymerase) binds to promoter DNA sites and forms a stable closed complex, unable to proceed to transcription. The closed complex must be remodelled using energy from ATP hydrolysis provided by bEBPs to melt DNA and initiate transcription. Recently, large amounts of structural and biochemical data have produced insights into how ATP hydrolysis within the active site of bEBPs is coupled to the re-modelling of the closed complex. In the present article, we review some of the key nucleotides, mutations and techniques used and how they have contributed towards our understanding of the function of bEBPs.

  17. Chirality Switching by Martensitic Transformation in Protein Cylindrical Crystals: Application to Bacterial Flagella

    Science.gov (United States)

    Komai, Ricardo Kiyohiro

    Martensitic transformations provide unique engineering properties that, when designed properly, become important parts of new technology. Martensitic transformations have been studied for many years in traditional alloys (iron, steel, titanium, etc.), however there is still much to be learned in regards to these transformations in biological materials. Olson and Hartman showed in 1982 that these transformations are also observed in bacterial flagella and T4 bacteriophage viral sheaths, allowing for propulsion of bacteria in a fluid environment and, for the virus, is responsible for the infection mechanism. This work demonstrates, using the bacterial flagella as an example, that these transformations can be modelled using thermodynamic methods that are also used to model the transformations in alloys. This thesis work attempts to explain the transformations that occur in bacterial flagella, which are capable of small strain, highly reversible martensitic transformations. The first stress/temperature phase diagrams of these flagella were created by adding the mechanical energy of the transformation of the flagella to limited chemical thermodynamics information of the transformation. Mechanical energy is critical to the transformation process because the bacterial body applies a torque to the radius of the flagella. Finally, work has begun and will be completed in regards to understanding the kinetics of the transformation of the flagella. The motion of the transformation interface can be predicted by using a Landau-Ginzburg model. The crystallography of the transformation in bacterial flagella is also being computed to determine the invariant lines of transformation that occur within this cylindrical crystal. This work has shown that it is possible to treat proteins in a similar manner that alloys are treated when using thermodynamic modelling. Much can be learned from translating what is known regarding phase transformations in hard material systems to soft, organic

  18. Phorbol Esters from Jatropha Meal Triggered Apoptosis, Activated PKC-δ, Caspase-3 Proteins and Down-Regulated the Proto-Oncogenes in MCF-7 and HeLa Cancer Cell Lines

    Directory of Open Access Journals (Sweden)

    Syahida Ahmad

    2012-09-01

    Full Text Available Jatropha meal produced from the kernel of Jatropha curcas Linn. grown in Malaysia contains phorbol esters (PEs. The potential benefits of PEs present in the meal as anticancer agent are still not well understood. Hence, this study was conducted to evaluate the cytotoxic effects and mode of actions of PEs isolated from Jatropha meal against breast (MCF-7 and cervical (HeLa cancer cell lines. Isolated PEs inhibited cells proliferation in a dose-dependent manner of both MCF-7 and HeLa cell lines with the IC50 of 128.6 ± 2.51 and 133.0 ± 1.96 µg PMA equivalents/mL respectively, while the values for the phorbol 12-myristate 13-acetate (PMA as positive control were 114.7 ± 1.73 and 119.6 ± 3.73 µg/mL, respectively. Microscopic examination showed significant morphological changes that resemble apoptosis in both cell lines when treated with PEs and PMA at IC50 concentration after 24 h. Flow cytometry analysis and DNA fragmentation results confirmed the apoptosis induction of PEs and PMA in both cell lines. The PEs isolated from Jatropha meal activated the PKC-δ and down-regulated the proto-oncogenes (c-Myc, c-Fos and c-Jun. These changes probably led to the activation of Caspase-3 protein and apoptosis cell death occurred in MCF-7 and HeLa cell lines upon 24 h treatment with PEs and PMA. Phorbol esters of Jatropha meal were found to be promising as an alternative to replace the chemotherapeutic drugs for cancer therapy.

  19. Phorbol esters from Jatropha meal triggered apoptosis, activated PKC-δ, caspase-3 proteins and down-regulated the proto-oncogenes in MCF-7 and HeLa cancer cell lines.

    Science.gov (United States)

    Oskoueian, Ehsan; Abdullah, Norhani; Ahmad, Syahida

    2012-09-10

    Jatropha meal produced from the kernel of Jatropha curcas Linn. grown in Malaysia contains phorbol esters (PEs). The potential benefits of PEs present in the meal as anticancer agent are still not well understood. Hence, this study was conducted to evaluate the cytotoxic effects and mode of actions of PEs isolated from Jatropha meal against breast (MCF-7) and cervical (HeLa) cancer cell lines. Isolated PEs inhibited cells proliferation in a dose-dependent manner of both MCF-7 and HeLa cell lines with the IC₅₀ of 128.6 ± 2.51 and 133.0 ± 1.96 µg PMA equivalents/mL respectively, while the values for the phorbol 12-myristate 13-acetate (PMA) as positive control were 114.7 ± 1.73 and 119.6 ± 3.73 µg/mL, respectively. Microscopic examination showed significant morphological changes that resemble apoptosis in both cell lines when treated with PEs and PMA at IC₅₀ concentration after 24 h. Flow cytometry analysis and DNA fragmentation results confirmed the apoptosis induction of PEs and PMA in both cell lines. The PEs isolated from Jatropha meal activated the PKC-δ and down-regulated the proto-oncogenes (c-Myc, c-Fos and c-Jun). These changes probably led to the activation of Caspase-3 protein and apoptosis cell death occurred in MCF-7 and HeLa cell lines upon 24 h treatment with PEs and PMA. Phorbol esters of Jatropha meal were found to be promising as an alternative to replace the chemotherapeutic drugs for cancer therapy.

  20. 饲粮蛋白质水平和棉籽粕取代豆粕对肉牛育肥的影响%Effects of Dietary Protein Level and Replacing Soybean Meal with Cottonseed Meal on Fattening of Beef Cattle

    Institute of Scientific and Technical Information of China (English)

    荆元强; 宋恩亮; 成海建; 刘晓牧; 赵红波; 刘桂芬; 谭秀文; 杨维仁; 万发春

    2012-01-01

    In order to study the effects of protein level and replacing soybean meal with cottonseed meal on fattening of beef cattle, diets with different protein levels and costs were prepared by replacing soybean meal with cottonseed meal based on meeting nutrient requirement of beef cattle. Forty healthy first-filial generation beef cattle (Japanese black cattle ♂×Luxi yellow cattle 9 ) with similar age (average age was 28-month-old) and body weight [average body weight was (678 ±122) kg] were randomly divided into 4 experimental groups with 10 beef steers per group. The adjustment period lasted for 15 days, and the experimental period lasted for 240 days. The results showed as follows; compared with the group with the diet containing 12. 8% protein, the daily gain of beef cattle in the group with the diet containing 14. 8% protein was increased by 18. 57% (P >0. 05). The dressing percentage, meat percentage, rib fat thickness and backfat thickness of beef cattle fed 14.8% protein diet were significantly increased than those of beef cattle fed 12. 8% protein diet(P 0. 05). Under the same protein level, partial or whole replacing soybean meal with cottonseed meal had no effect on the daily gain and carcass traits of beef cattle (P >0. 05) , but the unit price of diets and costs of per kilogram of weight gain in cottonseed meal group were lower than those in soybean meal group. In conclusion, using cottonseed meal instead of soybean meal in the later stage of fattening of beef cattle is viable to reduce feeding costs. The demand of protein level for beef cattle recommend by current Feeding Standard of Fattening of Beef Cattle (2004) is lower than that for first-filial generation cattle (Japanese black cattle ♂ × Luxi yellow cattle 9 ) in this experiment.%本试验在满足肉牛营养需要的基础上,采用棉籽粕替代饲粮中的豆粕,形成不同蛋白质水平和成本的饲粮,旨在探讨饲粮蛋白质水平和棉籽粕替代豆粕对肉牛育肥的影

  1. Protein L. A bacterial Ig-binding protein that activates human basophils and mast cells.

    Science.gov (United States)

    Patella, V; Casolaro, V; Björck, L; Marone, G

    1990-11-01

    Peptostreptococcus magnus strain 312 (10(6) to 10(8)/ml), which synthesizes a protein capable of binding to kappa L chains of human Ig (protein L), stimulated the release of histamine from human basophils in vitro. P. magnus strain 644, which does not synthesize protein L, did not induce histamine secretion. Soluble protein L (3 x 10(-2) to 3 micrograms/ml) induced histamine release from human basophils. The characteristics of the release reaction were similar to those of rabbit IgG anti-Fc fragment of human IgE (anti-IgE): it was Ca2(+)- and temperature-dependent, optimal release occurring at 37 degrees C in the presence of 1.0 mM extracellular Ca2+. There was an excellent correlation (r = 0.82; p less than 0.001) between the maximal percent histamine release induced by protein L and that induced by anti-IgE, as well as between protein L and protein A from Staphylococcus aureus (r = 0.52; p less than 0.01). Preincubation of basophils with either protein L or anti-IgE resulted in complete cross-desensitization to a subsequent challenge with the heterologous stimulus. IgE purified from myeloma patients PS and PP (lambda-chains) blocked anti-IgE-induced histamine release but failed to block the histamine releasing activity of protein L. In contrast, IgE purified from myeloma patient ADZ (kappa-chains) blocked both anti-IgE- and protein L-induced releases, whereas human polyclonal IgG selectively blocked protein L-induced secretion. Protein L acted as a complete secretagogue, i.e., it activated basophils to release sulfidopeptide leukotriene C4 as well as histamine. Protein L (10(-1) to 3 micrograms/ml) also induced the release of preformed (histamine) and de novo synthesized mediators (leukotriene C4 and/or PGD2) from mast cells isolated from lung parenchyma and skin tissues. Intradermal injections of protein L (0.01 to 10 micrograms/ml) in nonallergic subjects caused a dose-dependent wheal-and-flare reaction. Protein L activates human basophils and mast cells in

  2. Effects of extruding wheat dried distillers grains with solubles with peas or canola meal on ruminal fermentation, microbial protein synthesis, nutrient digestion, and milk production in dairy cows.

    Science.gov (United States)

    Claassen, R M; Christensen, D A; Mutsvangwa, T

    2016-09-01

    Our objective was to examine the effects of feeding coextruded and nonextruded supplements consisting of wheat dried distillers grains with solubles with peas (WDDGS-peas) or canola meal (WDDGS-CM) on ruminal fermentation, omasal flow, and production performance in Holstein cows. Eight cows (4 ruminally cannulated) were used in a replicated 4×4 Latin square with 28-d periods and a 2×2 factorial arrangement of dietary treatments. Dietary treatments were coextruded or nonextruded mixtures of WDDGS-peas and WDDGS-CM that were included in total mixed rations at 15.1% [dry matter (DM) basis]. Diet had no effect on DM intake. Milk yield was greater in cows fed coextruded diets compared with those fed nonextruded diets. Milk fat content was greater in cows fed nonextruded diets compared with those fed coextruded diets, but milk fat yield was greater in cows fed coextruded diets compared with those fed nonextruded diets. Milk yield tended to be greater and milk protein yield was greater in cows fed WDDGS-peas compared with those fed WDDGS-CM. Cows fed nonextruded diets had a greater milk urea-N concentration compared with those fed coextruded diets. Cows fed coextruded diets had greater ruminal digestion of DM and tended to have greater ruminal digestion of organic matter compared with those fed nonextruded diets. Total-tract digestibilities of organic matter, crude protein, ether extract, and starch were greater, whereas that of acid detergent fiber and neutral detergent fiber tended to be greater in cows fed coextruded compared with those fed nonextruded diets. Total-tract digestibility of ether extract was lower whereas that of starch was greater and that of crude protein tended to be greater in cows fed WDDGS-peas compared with those fed WDDGS-CM. Total N excretion and milk N efficiency were unaffected by diet. Ruminal NH3-N concentration tended to be greater in cows fed WDDGS-CM compared with those fed WDDGS-peas. Ruminal propionate concentration was greater whereas

  3. Bacterial ortholog of mammalian translocator protein (TSPO with virulence regulating activity.

    Directory of Open Access Journals (Sweden)

    Annelise Chapalain

    Full Text Available The translocator protein (TSPO, previously designated as peripheral-type benzodiazepine receptor, is a protein mainly located in the outer mitochondrial membrane of eukaryotic cells. TSPO is implicated in major physiological functions and functionally associated with other proteins such as the voltage-dependent anionic channel, also designated as mitochondrial porin. Surprisingly, a TSPO-related protein was identified in the photosynthetic bacterium Rhodobacter sphaeroides but it was initially considered as a relict of evolution. In the present study we cloned a tspO gene in Pseudomonas fluorescens MF37, a non-photosynthetic eubacterium and we used bioinformatics tools to identify TSPO in the genome of 97 other bacteria. P. fluorescens TSPO was recognized by antibodies against mouse protein and by PK 11195, an artificial ligand of mitochondrial TSPO. As in eukaryotes, bacterial TSPO appears functionally organized as a dimer and the apparent Kd for PK 11195 is in the same range than for its eukaryotic counterpart. When P. fluorescens MF37 was treated with PK 11195 (10(-5 M adhesion to living or artificial surfaces and biofilm formation activity were increased. Conversely, the apoptotic potential of bacteria on eukaryotic cells was significantly reduced. This effect of PK11195 was abolished in a mutant of P. fluorescens MF37 deficient for its major outer membrane porin, OprF. The present results demonstrate the existence of a bacterial TSPO that shares common structural and functional characteristics with its mammalian counterpart. This protein, apparently involved in adhesion and virulence, reveals the existence of a possible new inter kingdom signalling system and suggests that the human microbiome should be involuntarily exposed to the evolutionary pressure of benzodiazepines and related molecules. This discovery also represents a promising opportunity for the development of alternative antibacterial strategies.

  4. 葵花粕分离蛋白对黑米面包面团粉质特性的影响%Effect of Sunflower Meal Isolated Protein on the Farinograph Characteristics of Black Rice Bread Dough

    Institute of Scientific and Technical Information of China (English)

    李云玲; 朱效兵; 郭淑文; 石晶红

    2016-01-01

    研究添加葵花粕分离蛋白对黑米面包混粉面团粉质特性的影响,为葵花粕分离蛋白作为功能性材料开发功能性食品提供理论依据。以面包粉和黑米粉为原料,添加一定比例葵花粕分离蛋白,利用布拉本德(Brabender)粉质仪测定面团吸水率、形成时间、稳定时间和弱化度。面包粉中添加30%黑米粉、4%谷朊粉、1%~5%的葵花粕分离蛋白后,混粉面团的吸水率增加,形成时间和稳定时间先增加后减少,弱化度先下降后上升。添加1%~3%的葵花粕分离蛋白,可以改善黑米面包混粉的粉质特性,进而改变其加工特性。%The effect of adding sunflower meal isolated protein on the farinograph characteristics of black rice bread dough were studied,it provided a theoretical basis for sunflower meal isolated protein as a functional mate-rial to develop functional foods. Bread flour and black rice flour as raw materials,adding the right amount of sunflower meal isolated protein,Brabender farinograph was used to determination dough water absorption,devel-opment time,stability time,softening degree of mixed dough. Adding 30%black rice flour,4%gluten flour, 1 %-5%sunflower meal isolated protein in the bread flour,the water absorption of mixed dough increased,the development time and the stability time increased first and then decreased,the softening degree decreased first and then increased. Adding 1%-3%sunflower meal isolated protein could improve the farinograph properties of black rice bread mixed dough,and then change the processing characteristics.

  5. Expression of lysozymes from Erwinia amylovora phages and Erwinia genomes and inhibition by a bacterial protein.

    Science.gov (United States)

    Müller, Ina; Gernold, Marina; Schneider, Bernd; Geider, Klaus

    2012-01-01

    Genes coding for lysozyme-inhibiting proteins (Ivy) were cloned from the chromosomes of the plant pathogens Erwinia amylovora and Erwinia pyrifoliae. The product interfered not only with activity of hen egg white lysozyme, but also with an enzyme from E. amylovora phage ΦEa1h. We have expressed lysozyme genes from the genomes of three Erwinia species in Escherichia coli. The lysozymes expressed from genes of the E. amylovora phages ΦEa104 and ΦEa116, Erwinia chromosomes and Arabidopsis thaliana were not affected by Ivy. The enzyme from bacteriophage ΦEa1h was fused at the N- or C-terminus to other peptides. Compared to the intact lysozyme, a His-tag reduced its lytic activity about 10-fold and larger fusion proteins abolished activity completely. Specific protease cleavage restored lysozyme activity of a GST-fusion. The bacteriophage-encoded lysozymes were more active than the enzymes from bacterial chromosomes. Viral lyz genes were inserted into a broad-host range vector, and transfer to E. amylovora inhibited cell growth. Inserted in the yeast Pichia pastoris, the ΦEa1h-lysozyme was secreted and also inhibited by Ivy. Here we describe expression of unrelated cloned 'silent' lyz genes from Erwinia chromosomes and a novel interference of bacterial Ivy proteins with a viral lysozyme.

  6. UGT-29 protein expression and localization during bacterial infection in Caenorhabditis elegans

    Science.gov (United States)

    Wong, Rui-Rui; Lee, Song-Hua; Nathan, Sheila

    2014-09-01

    The nematode Caenorhabditis elegans is routinely used as an animal model to delineate complex molecular mechanisms involved in the host response to pathogen infection. Following up on an earlier study on host-pathogen interaction, we constructed a ugt-29::GFP transcriptional fusion transgenic worm strain to examine UGT-29 protein expression and localization upon bacterial infection. UGT-29 orthologs can be found in higher organisms including humans and is proposed as a member of the UDP-Glucoronosyl Transferase family of proteins which are involved in phase II detoxification of compounds detrimental to the host organism. Under uninfected conditions, UGT-29::GFP fusion protein was highly expressed in the C. elegans anterior pharynx and intestine, two major organs involved in detoxification. We further evaluated the localization of the enzyme in worms infected with the bacterial pathogen, Burkholderia pseudomallei. The infected ugt-29::GFP transgenic strain exhibited increased fluorescence in the pharynx and intestine with pronounced fluorescence also extending to body wall muscle. This transcriptional fusion GFP transgenic worm is a convenient and direct tool to provide information on UGT detoxification enzyme gene expression and could be a useful tool for a number of diverse applications.

  7. Structural studies of bacterial transcriptional regulatory proteins by multidimensional heteronuclear NMR

    Energy Technology Data Exchange (ETDEWEB)

    Volkman, B.F.

    1995-02-01

    Nuclear magnetic resonance spectroscopy was used to elucidate detailed structural information for peptide and protein molecules. A small peptide was designed and synthesized, and its three-dimensional structure was calculated using distance information derived from two-dimensional NMR measurements. The peptide was used to induce antibodies in mice, and the cross-reactivity of the antibodies with a related protein was analyzed with enzyme-linked immunosorbent assays. Two proteins which are involved in regulation of transcription in bacteria were also studied. The ferric uptake regulation (Fur) protein is a metal-dependent repressor which controls iron uptake in bacteria. Two- and three-dimensional NMR techniques, coupled with uniform and selective isotope labeling allowed the nearly complete assignment of the resonances of the metal-binding domain of the Fur protein. NTRC is a transcriptional enhancer binding protein whose N-terminal domain is a {open_quote}receiver domain{close_quote} in the family of {open_quote}two-component{close_quote} regulatory systems. Phosphorylation of the N-terminal domain of NTRC activates the initiation of transcription of aeries encoding proteins involved in nitrogen regulation. Three- and four-dimensional NMR spectroscopy methods have been used to complete the resonance assignments and determine the solution structure of the N-terminal receiver domain of the NTRC protein. Comparison of the solution structure of the NTRC receiver domain with the crystal structures of the homologous protein CheY reveals a very similar fold, with the only significant difference being the position of helix 4 relative to the rest of the protein. The determination of the structure of the NTRC receiver domain is the first step toward understanding a mechanism of signal transduction which is common to many bacterial regulatory systems.

  8. Bacterial resistance to complement killing mediated by the Ail protein of Yersinia enterocolitica.

    OpenAIRE

    Bliska, J B; Falkow, S

    1992-01-01

    Ail is a 17-kDa outer membrane Yersinia protein that mediates bacterial attachment to, and invasion of, cultured epithelial cells. We report here an alternative role for Ail in the pathogenesis of Yersinia infection. We found that Escherichia coli HB101 harboring the 4-kilobase recombinant ail clone pVM102 were highly resistant to killing in up to 50% normal human serum. A 674-base-pair fragment of DNA from pVM102, which encodes the ail gene, was inserted into pUC18 and shown to promote full ...

  9. A Simple and Rapid Method for Preparing a Cell-Free Bacterial Lysate for Protein Synthesis

    Science.gov (United States)

    Kaduri, Maya; Shainsky-Roitman, Janna; Goldfeder, Mor; Ivanir, Eran; Benhar, Itai; Shoham, Yuval; Schroeder, Avi

    2016-01-01

    Cell-free protein synthesis (CFPS) systems are important laboratory tools that are used for various synthetic biology applications. Here, we present a simple and inexpensive laboratory-scale method for preparing a CFPS system from E. coli. The procedure uses basic lab equipment, a minimal set of reagents, and requires less than one hour to process the bacterial cell mass into a functional S30-T7 extract. BL21(DE3) and MRE600 E. coli strains were used to prepare the S30-T7 extract. The CFPS system was used to produce a set of fluorescent and therapeutic proteins of different molecular weights (up to 66 kDa). This system was able to produce 40–150 μg-protein/ml, with variations depending on the plasmid type, expressed protein and E. coli strain. Interestingly, the BL21-based CFPS exhibited stability and increased activity at 40 and 45°C. To the best of our knowledge, this is the most rapid and affordable lab-scale protocol for preparing a cell-free protein synthesis system, with high thermal stability and efficacy in producing therapeutic proteins. PMID:27768741

  10. Structural and sequence analysis of imelysin-like proteins implicated in bacterial iron uptake.

    Directory of Open Access Journals (Sweden)

    Qingping Xu

    Full Text Available Imelysin-like proteins define a superfamily of bacterial proteins that are likely involved in iron uptake. Members of this superfamily were previously thought to be peptidases and were included in the MEROPS family M75. We determined the first crystal structures of two remotely related, imelysin-like proteins. The Psychrobacter arcticus structure was determined at 2.15 Å resolution and contains the canonical imelysin fold, while higher resolution structures from the gut bacteria Bacteroides ovatus, in two crystal forms (at 1.25 Å and 1.44 Å resolution, have a circularly permuted topology. Both structures are highly similar to each other despite low sequence similarity and circular permutation. The all-helical structure can be divided into two similar four-helix bundle domains. The overall structure and the GxHxxE motif region differ from known HxxE metallopeptidases, suggesting that imelysin-like proteins are not peptidases. A putative functional site is located at the domain interface. We have now organized the known homologous proteins into a superfamily, which can be separated into four families. These families share a similar functional site, but each has family-specific structural and sequence features. These results indicate that imelysin-like proteins have evolved from a common ancestor, and likely have a conserved function.

  11. Bacterial Obg proteins: GTPases at the nexus of protein and DNA synthesis.

    Science.gov (United States)

    Kint, Cyrielle; Verstraeten, Natalie; Hofkens, Johan; Fauvart, Maarten; Michiels, Jan

    2014-08-01

    Obg proteins (also known as ObgE, YhbZ and CgtA) are conserved P-loop GTPases, essential for growth in bacteria. Like other GTPases, Obg proteins cycle between a GTP-bound ON and a GDP-bound OFF state, thereby controlling cellular processes. Interestingly, the in vitro biochemical properties of Obg proteins suggest that they act as sensors for the cellular GDP/GTP pools and adjust their activity according to the cellular energy status. Obg proteins have been attributed a host of cellular functions, including roles in essential cellular processes (DNA replication, ribosome maturation) and roles in different stress adaptation pathways (stringent response, sporulation, general stress response). This review summarizes the current knowledge on Obg activity and function. Furthermore, we present a model that integrates the different functions of Obg by assigning it a fundamental role in cellular physiology, at the hub of protein and DNA synthesis. In particular, we believe that Obg proteins might provide a connection between different global pathways in order to fine-tune cellular processes in response to a given energy status.

  12. FRACIONAMENTO DE PROTEÍNAS DE SILAGEM DE CAPIM-ELEFANTE EMURCHECIDO OU COM FARELO DE CACAU PROTEIN FRACTIONING OF SILAGE OF ELEPHANTGRASS WILTED OR WITH COCOA MEAL

    Directory of Open Access Journals (Sweden)

    Gleidson Giordano Pinto de Carvalho

    2008-10-01

    Full Text Available

    Desenvolveu-se o experimento para determinar as frações que compõem as proteínas da silagem de capim-elefante (Pennisetum purpureum Schum. cv. Camaroon submetido ao emurchecimento ou à adição de diferentes níveis de farelo de cacau. O capim-elefante utilizado foi colhido aos 50 dias de rebrota após o corte de uniformização e submetido aos seguintes tratamentos: capim-elefante emurchecido ao sol por oito horas, e capim-elefante sem emurchecimento com níveis de 0 %, 7 %, 14%, 21 % e 28 % de farelo de cacau (FC (% da matéria natural. Acondicionou-se o material em silos de PVC com capacidade para 5,3 litros, que foram abertos após 45 dias. Para todas as frações de proteínas estimadas, o tratamento emurchecido apresentou valores semelhantes (P>0,05 ao do tratamento sem emurchecimento. As frações protéicas foram influenciadas pelas adições de FC, verificando-se redução dos teores das frações A e B1+B2 e aumentos das frações B3 e C, para os níveis crescentes de FC.

    PALAVRAS-CHAVES: Conservação de forragens, forrageira, Pennisetum purpureum Schum. cv. Cameroon, subproduto, Theobroma cacao L.

    The experiment was conducted to determine the fractions that compose the protein of silage on the submitted elephant grass forage to wilting under the sun light for eight hours. Other treatments involved the same elephant grass without exposing to sun light but with addition of 0, 7, 14, 21, and 28% of cocoa meal (CM at the ensilage processing. The PVC silos used in the experiment were 5.3 liters in capacity, and were opened in 45 days. To all protein-estimated fractions, the wilted treatment showed similar values (P>.05 to the treatment without wilting. The protein fractions were influenced by CM addictions, verifying reduction in contents of A and B1+B2 fractions and increase in B3 and C fractions, with CM increasing levels

  13. Validation of extrusion as a killing step for Enterococcus faecium in a balanced carbohydrate-protein meal by using a response surface design.

    Science.gov (United States)

    Bianchini, Andreia; Stratton, Jayne; Weier, Steve; Hartter, Timothy; Plattner, Brian; Rokey, Galen; Hertzel, Gerry; Gompa, Lakshmi; Martinez, Bismarck; Eskridge, Andkent M

    2012-09-01

    Outbreaks of salmonellosis and recalls of low-moisture foods including extruded products highlight the need for the food and feed industries to validate their extrusion processes to ensure the destruction of pathogenic microorganisms. Response surface methodology was employed to study the effect of moisture and temperature on inactivation by extrusion of Enterococcus faecium NRRL B-2354 in a carbohydrate-protein mix. A balanced carbohydrate-protein mix was formulated to different combinations of moisture contents, ranging from 24.9 to 31.1%, and each was inoculated with a pure culture of E. faecium to a final level of 5 log CFU/g. Each mix of various moistures was then extruded in a pilot scale extruder at different temperatures (ranging from 67.5 to 85°C). After the extruder was allowed to equilibrate for 10 min, samples were collected in sterile bags, cooled in dry ice, and stored at 4°C prior to analysis. E. faecium was enumerated with tryptic soy agar and membrane Enterococcus media, followed by incubation at 35°C for 48 h. Each extrusion was repeated twice, with the central point of the design being repeated four times. From each extrusion, three subsamples were collected for microbial counts and moisture determination. Based on the results, the response surface model was y = 185.04 - 3.11X(1) - 4.23X(2) + 0.02X(1)(2) - 0.004X(1)X(2) + 0.08X(2)(2), with a good fit (R(2) = 0.92), which demonstrated the effects of moisture and temperature on the inactivation of E. faecium during extrusion. According to the response surface analysis, the greatest reduction of E. faecium for the inoculation levels studied here (about 5 log) in a carbohydrate-protein meal would occur at the temperature of 81.1°C and moisture content of 28.1%. Other temperature and moisture combinations needed to achieve specific log reductions were plotted in a three-dimensional response surface graph.

  14. Exogenous enzyme complex prevents intestinal soybean meal-induced enteritis in Mugil liza (Valenciennes, 1836 juvenile.

    Directory of Open Access Journals (Sweden)

    LEONARDO R.V. RAMOS

    Full Text Available ABSTRACT Four soybean meal-based diets containing increasing levels of an enzyme complex (E50, E100, E150 and E200 at 50, 100, 150 and 200 g ton-1, respectively and one soybean meal-based diet without the enzyme complex (E0 were fed in triplicate to M. liza juveniles in a semi-static flow system with 20 fish per tank for 75 days. There were no differences between the treatments for animal performance parameters, but fish fed the enzyme complex treatment exhibited significantly (P<0.05 higher values of calcium bone retention compared with control fish. Although there was no relationship between bacterial counts in different sections of the gastrointestinal tract or enzyme levels, filamentous bacteria were increased in E50 compared with E150. All of the treatments resulted in higher bacterial counts in the stomach than in intestinal segments. Histological screening showed serious to moderate infiltration of inflammatory cells, modification in villus morphology and necrosis in some cases in fish fed the E0 diet. In addition, fish from the E0 treatment exhibited significantly (P<0.05 lower lipid deposition in the peritoneal cavity. Therefore, the use of low levels of exogenous enzyme is recommended in diets for M. liza when soybean meal is used as the main source of protein.

  15. Biochemical Roles for Conserved Residues in the Bacterial Fatty Acid-binding Protein Family.

    Science.gov (United States)

    Broussard, Tyler C; Miller, Darcie J; Jackson, Pamela; Nourse, Amanda; White, Stephen W; Rock, Charles O

    2016-03-18

    Fatty acid kinase (Fak) is a ubiquitous Gram-positive bacterial enzyme consisting of an ATP-binding protein (FakA) that phosphorylates the fatty acid bound to FakB. In Staphylococcus aureus, Fak is a global regulator of virulence factor transcription and is essential for the activation of exogenous fatty acids for incorporation into phospholipids. The 1.2-Å x-ray structure of S. aureus FakB2, activity assays, solution studies, site-directed mutagenesis, and in vivo complementation were used to define the functions of the five conserved residues that define the FakB protein family (Pfam02645). The fatty acid tail is buried within the protein, and the exposed carboxyl group is bound by a Ser-93-fatty acid carboxyl-Thr-61-His-266 hydrogen bond network. The guanidinium of the invariant Arg-170 is positioned to potentially interact with a bound acylphosphate. The reduced thermal denaturation temperatures of the T61A, S93A, and H266A FakB2 mutants illustrate the importance of the hydrogen bond network in protein stability. The FakB2 T61A, S93A, and H266A mutants are 1000-fold less active in the Fak assay, and the R170A mutant is completely inactive. All FakB2 mutants form FakA(FakB2)2 complexes except FakB2(R202A), which is deficient in FakA binding. Allelic replacement shows that strains expressing FakB2 mutants are defective in fatty acid incorporation into phospholipids and virulence gene transcription. These conserved residues are likely to perform the same critical functions in all bacterial fatty acid-binding proteins.

  16. Nutritive value of fish meal.

    Directory of Open Access Journals (Sweden)

    Hossain M.E.

    2016-12-01

    Full Text Available The study was undertaken to find out the variations in the chemical composition of different types of fish meal available in the metropolitan areas of Chittagong, Bangladesh. Fifteen different types of fish meal samples were collected from study areas. Chemical analyses of the samples were carried out in triplicate for dry matter (DM, crude protein (CP, crude fiber (CF, nitrogen free extract (NFE, ether extract (EE and total ash (TA in the animal nutrition and poultry research and training centre (PRTC laboratory, Chittagong Veterinary and Animal Sciences University, Chittagong, Bangladesh. Metabolizable energy (ME was estimated mathematically for all samples by using standard formula. Results indicated that, DM, CP, NFE, EE, TA and ME content significantly differed (P0.05 variation was found in the CF contents of the samples. DM content varied from 86.7 to 96.7%, CP content varied from 31.3 to 61.2%, EE content varied from 0.8 to 23.5%, NFE content varied from 0.6 to 14.6%, Ash content varied from 13.3 to 36.7% and ME content varied from 1788.4 to 3478.8 kcal/kg. It could therefore be inferred that, the chemical composition of fish meal available in the local market are widely variable. Therefore, every sample needs to be analyzed before use for ration formulation.

  17. The pneumococcal serine-rich repeat protein is an intra-species bacterial adhesin that promotes bacterial aggregation in vivo and in biofilms.

    Directory of Open Access Journals (Sweden)

    Carlos J Sanchez

    Full Text Available The Pneumococcal serine-rich repeat protein (PsrP is a pathogenicity island encoded adhesin that has been positively correlated with the ability of Streptococcus pneumoniae to cause invasive disease. Previous studies have shown that PsrP mediates bacterial attachment to Keratin 10 (K10 on the surface of lung cells through amino acids 273-341 located in the Basic Region (BR domain. In this study we determined that the BR domain of PsrP also mediates an intra-species interaction that promotes the formation of large bacterial aggregates in the nasopharynx and lungs of infected mice as well as in continuous flow-through models of mature biofilms. Using numerous methods, including complementation of mutants with BR domain deficient constructs, fluorescent microscopy with Cy3-labeled recombinant (rBR, Far Western blotting of bacterial lysates, co-immunoprecipitation with rBR, and growth of biofilms in the presence of antibodies and competitive peptides, we determined that the BR domain, in particular amino acids 122-166 of PsrP, promoted bacterial aggregation and that antibodies against the BR domain were neutralizing. Using similar methodologies, we also determined that SraP and GspB, the Serine-rich repeat proteins (SRRPs of Staphylococcus aureus and Streptococcus gordonii, respectively, also promoted bacterial aggregation and that their Non-repeat domains bound to their respective SRRPs. This is the first report to show the presence of biofilm-like structures in the lungs of animals infected with S. pneumoniae and show that SRRPs have dual roles as host and bacterial adhesins. These studies suggest that recombinant Non-repeat domains of SRRPs (i.e. BR for S. pneumoniae may be useful as vaccine antigens to protect against Gram-positive bacteria that cause infection.

  18. Coordination of genomic structure and transcription by the main bacterial nucleoid-associated protein HU.

    Science.gov (United States)

    Berger, Michael; Farcas, Anca; Geertz, Marcel; Zhelyazkova, Petya; Brix, Klaudia; Travers, Andrew; Muskhelishvili, Georgi

    2010-01-01

    The histone-like protein HU is a highly abundant DNA architectural protein that is involved in compacting the DNA of the bacterial nucleoid and in regulating the main DNA transactions, including gene transcription. However, the coordination of the genomic structure and function by HU is poorly understood. Here, we address this question by comparing transcript patterns and spatial distributions of RNA polymerase in Escherichia coli wild-type and hupA/B mutant cells. We demonstrate that, in mutant cells, upregulated genes are preferentially clustered in a large chromosomal domain comprising the ribosomal RNA operons organized on both sides of OriC. Furthermore, we show that, in parallel to this transcription asymmetry, mutant cells are also impaired in forming the transcription foci-spatially confined aggregations of RNA polymerase molecules transcribing strong ribosomal RNA operons. Our data thus implicate HU in coordinating the global genomic structure and function by regulating the spatial distribution of RNA polymerase in the nucleoid.

  19. A bacterial protein enhances the release and efficacy of liposomal cancer drugs.

    Science.gov (United States)

    Cheong, Ian; Huang, Xin; Bettegowda, Chetan; Diaz, Luis A; Kinzler, Kenneth W; Zhou, Shibin; Vogelstein, Bert

    2006-11-24

    Clostridium novyi-NT is an anaerobic bacterium that can infect hypoxic regions within experimental tumors. Because C. novyi-NT lyses red blood cells, we hypothesized that its membrane-disrupting properties could be exploited to enhance the release of liposome-encapsulated drugs within tumors. Here, we show that treatment of mice bearing large, established tumors with C. novyi-NT plus a single dose of liposomal doxorubicin often led to eradication of the tumors. The bacterial factor responsible for the enhanced drug release was identified as a previously unrecognized protein termed liposomase. This protein could potentially be incorporated into diverse experimental approaches for the specific delivery of chemotherapeutic agents to tumors.

  20. Minimum inhibitory concentration of irradiated silk protein powder for bacterial activity

    Energy Technology Data Exchange (ETDEWEB)

    Tuntivisoottikul, Kunya; Bunnak, Jintana [King Mongkut' s Institute of Technology Chaokhun Taharn Ladkrabang, Faculty of Industrial Education, Dept. of Agricultural Educaiton, Bangkok (Thailand); Kume, Tamikazu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    2002-03-01

    The objective of this research was to study a minimum concentration level of irradiated silk protein powder, which inhibited bacterial activity. The concentration of 100 kGy irradiated silk protein powder (ISP) solution was ranged from 5 to 15% in distilled water. The activities of three types of bacteria, Escherichia coli B/r, Bacillus subtilis M3-1 and Staphylococcus aureus K, were tested by using minimum inhibition concentration method (MIC). The results indicated that the minimum concentration level that inhibited growth of E. coli B/r and S. aureus K was 5% ISP and all concentration levels studied could not inhibit the Bacilus subtilis M3-1 activity. (author)

  1. Single-stranded DNA bound to bacterial cold-shock proteins: preliminary crystallographic and Raman analysis.

    Science.gov (United States)

    Bienert, Ralf; Zeeb, Markus; Dostál, Lubomir; Feske, Anette; Magg, Christine; Max, Klaas; Welfle, Heinz; Balbach, Jochen; Heinemann, Udo

    2004-04-01

    The cold-shock response has been described for several bacterial species. It is characterized by distinct changes in intracellular protein patterns whereby a set of cold-shock-inducible proteins become abundant. The major cold-shock proteins of Bacillus subtilis (Bs-CspB) and Bacillus caldolyticus (Bc-Csp) are small oligonucleotide/oligosaccharide-binding (OB) fold proteins that have been described as binding single-stranded nucleic acids. Bs-CspB (Mr = 7365) and Bc-Csp (Mr = 7333) were crystallized in the presence of the deoxyhexanucleotide (dT)6. Crystals of (dT)6 with Bs-CspB grew in the orthorhombic space group C222(1), with unit-cell parameters a = 49.0, b = 53.2, c = 77.0 A. Crystals with Bc-Csp grew in the primitive orthorhombic space group P2(1)2(1)2, with unit-cell parameters a = 74.3, b = 64.9, c = 31.2 A. These crystals diffract to maximal resolutions of 1.78 and 1.29 A, respectively. The presence of protein and DNA in the crystals was demonstrated by Raman spectroscopy.

  2. NClassG+: A classifier for non-classically secreted Gram-positive bacterial proteins

    Directory of Open Access Journals (Sweden)

    Pino Camilo

    2011-01-01

    Full Text Available Abstract Background Most predictive methods currently available for the identification of protein secretion mechanisms have focused on classically secreted proteins. In fact, only two methods have been reported for predicting non-classically secreted proteins of Gram-positive bacteria. This study describes the implementation of a sequence-based classifier, denoted as NClassG+, for identifying non-classically secreted Gram-positive bacterial proteins. Results Several feature-based classifiers were trained using different sequence transformation vectors (frequencies, dipeptides, physicochemical factors and PSSM and Support Vector Machines (SVMs with Linear, Polynomial and Gaussian kernel functions. Nested k-fold cross-validation (CV was applied to select the best models, using the inner CV loop to tune the model parameters and the outer CV group to compute the error. The parameters and Kernel functions and the combinations between all possible feature vectors were optimized using grid search. Conclusions The final model was tested against an independent set not previously seen by the model, obtaining better predictive performance compared to SecretomeP V2.0 and SecretPV2.0 for the identification of non-classically secreted proteins. NClassG+ is freely available on the web at http://www.biolisi.unal.edu.co/web-servers/nclassgpositive/

  3. ATP-dependent transcriptional activation by bacterial PspF AAA+protein.

    Science.gov (United States)

    Schumacher, Jörg; Zhang, Xiaodong; Jones, Susan; Bordes, Patricia; Buck, Martin

    2004-05-14

    Transcription activation by bacterial sigma(54)-dependent enhancer-binding proteins (EBPs) requires their tri-nucleotide hydrolysis to restructure the sigma(54) RNA polymerase (RNAP). EBPs share sequence similarity with guanine nucleotide binding-proteins and ATPases associated with various cellular activities (AAA) proteins, especially in the mononucleotide binding P-loop fold. Using the phage shock protein F (PspF) EBP, we identify P-loop residues responsible for nucleotide binding and hydrolysis, consistent with their roles in other P-loop NTPases. We show the refined low-resolution structure of an EBP, PspF, revealing a hexameric ring organisation characteristic of AAA proteins. Functioning of EBPs involves ATP binding, higher oligomer formation and ATP hydrolysis coupled to the restructuring of the RNAP. This is thought to be a highly coordinated multi-step process, but the nucleotide-driven mechanism of oligomerisation and ATP hydrolysis is little understood. Our kinetic and structural data strongly suggest that three PspF dimers assemble to form a hexamer upon nucleotide binding. During the ATP hydrolysis cycle, both ATP and ADP are bound to oligomeric PspF, in line with a sequential hydrolysis cycle. We identify a putative R-finger, and show its involvement in ATP hydrolysis. Substitution of this arginine residue results in nucleotide-independent formation of hexameric rings, structurally linking the putative R-finger and, by inference, a specific nucleotide interaction to the control of PspF oligomerisation.

  4. Effect of replacement of fish meal by meat and bone meal and poultry by-product meal in diets on the growth and immune response of Macrobrachium nipponense.

    Science.gov (United States)

    Yang, Yong; Xie, Shouqi; Lei, Wu; Zhu, Xiaoming; Yang, Yunxia

    2004-08-01

    The potential use of poultry by-product meal (PBM) and meat and bone meal (MBM) as alternative dietary protein sources for juvenile Macrobrachium nipponense was studied by a 70-day growth trial. Triplicate groups of M. nipponense (initial body weight: 0.37 g) were fed at 20.7-22.4 degrees C on each of the five isoenergetic and isonitrogenous diets (protein content about 38%) with different replacement of fish meal by MBM or PBM. The control diet used white fish meal as the sole protein source, the other four diets were prepared with 15% or 50% fish meal protein substituted by either MBM (MBM(15), MBM(50)) or PBM (PBM(15), PBM(50)). The results showed that replacement of fish meal by MBM in diets did not affect growth performance of M. nipponense (P > 0.05), while specific growth rate in PBM(15) was significantly higher than that in other groups (P meal protein in diets for M. nipponense.

  5. De novo generation of infectious prions with bacterially expressed recombinant prion protein.

    Science.gov (United States)

    Zhang, Zhihong; Zhang, Yi; Wang, Fei; Wang, Xinhe; Xu, Yuanyuan; Yang, Huaiyi; Yu, Guohua; Yuan, Chonggang; Ma, Jiyan

    2013-12-01

    The prion hypothesis is strongly supported by the fact that prion infectivity and the pathogenic conformer of prion protein (PrP) are simultaneously propagated in vitro by the serial protein misfolding cyclic amplification (sPMCA). However, due to sPMCA's enormous amplification power, whether an infectious prion can be formed de novo with bacterially expressed recombinant PrP (rPrP) remains to be satisfactorily resolved. To address this question, we performed unseeded sPMCA with rPrP in a laboratory that has never been exposed to any native prions. Two types of proteinase K (PK)-resistant and self-perpetuating recombinant PrP conformers (rPrP-res) with PK-resistant cores of 17 or 14 kDa were generated. A bioassay revealed that rPrP-res(17kDa) was highly infectious, causing prion disease in wild-type mice with an average survival time of about 172 d. In contrast, rPrP-res(14kDa) completely failed to induce any disease. Our findings reveal that sPMCA is sufficient to initiate various self-perpetuating PK-resistant rPrP conformers, but not all of them possess in vivo infectivity. Moreover, generating an infectious prion in a prion-free environment establishes that an infectious prion can be formed de novo with bacterially expressed rPrP.

  6. The participation of outer membrane proteins in the bacterial sensitivity to nanosilver.

    Science.gov (United States)

    Kędziora, Anna; Krzyżewska, Eva; Dudek, Bartłomiej; Bugla-Płoskońska, Gabriela

    2016-01-01

    The presented study is to analyze the participation of outer membrane proteins of Gram- negative bacteria in sensitivity to silver nanomaterials. The mechanism of interaction of silver with the bacterial cell is best described in this group of microorganisms. There are several theories regarding the effectiveness of antimicrobial ions and nanosilver, and at the indicated differences in the way they work. Outer membrane proteins of Gram-negative bacteria are involved in the procurement of silver from the environment and contribute to the development mechanisms of resistance to nanometals. They are measurable parameter in the field of cell phenotypic response to the presence of Gram-negative bacteria in the environment silver nanoforms: its properties, chemical composition, content or times of action. Proteomic methods (including two dimensional electrophoresis and MALDI‑TOF MS) are therefore relevant techniques for determining the susceptibility of bacteria to silver and the changes taking place in the outer membrane under the influence: uptime/exposure and physical and chemical parameters of silver nanomaterials. Many products containing nanosilver is still in the research phase in terms of physico‑chemical characteristics and biological activity, others have been already implemented in many industries. During the very fast nanotechnology developing and introduction to the market products based on the nanosilver the bacterial answer to nanosilver is needed.

  7. Disordered patterns in clustered Protein Data Bank and in eukaryotic and bacterial proteomes.

    Directory of Open Access Journals (Sweden)

    Michail Yu Lobanov

    Full Text Available We have constructed the clustered Protein Data Bank and obtained clusters of chains of different identity inside each cluster, http://bioinfo.protres.ru/st_pdb/. We have compiled the largest database of disordered patterns (141 from the clustered PDB where identity between chains inside of a cluster is larger or equal to 75% (version of 28 June 2010 by using simple rules of selection. The results of these analyses would help to further our understanding of the physicochemical and structural determinants of intrinsically disordered regions that serve as molecular recognition elements. We have analyzed the occurrence of the selected patterns in 97 eukaryotic and in 26 bacterial proteomes. The disordered patterns appear more often in eukaryotic than in bacterial proteomes. The matrix of correlation coefficients between numbers of proteins where a disordered pattern from the library of 141 disordered patterns appears at least once in 9 kingdoms of eukaryota and 5 phyla of bacteria have been calculated. As a rule, the correlation coefficients are higher inside of the considered kingdom than between them. The patterns with the frequent occurrence in proteomes have low complexity (PPPPP, GGGGG, EEEED, HHHH, KKKKK, SSTSS, QQQQQP, and the type of patterns vary across different proteomes, http://bioinfo.protres.ru/fp/search_new_pattern.html.

  8. Motion of single MreB bacterial actin proteins in Caulobacter show treadmilling in vivo

    Science.gov (United States)

    Moerner, W. E.; Kim, Soyeon; Gitai, Zemer; Kinkhabwala, Anika; McAdams, Harley; Shapiro, Lucy

    2006-03-01

    Ensemble imaging of a bacterial actin homologue, the MreB protein, suggests that the MreB proteins form a dynamic filamentous spiral along the long axis of the cell in Caulobacter crescentus. MreB contracts and expands along the cell axis and plays an important role in cell shape and polarity maintenance, as well as chromosome segregation and translocation of the origin of replication during cell division. In this study we investigated the real-time polymerization of MreB in Caulobacter crescentus using single-molecule fluorescence imaging. With time-lapse imaging, polymerized MreB could be distinguished from cytoplasmic MreB monomers, because single monomeric MreB showed fast motion characteristic of Brownian diffusion, while single polymerized MreB displayed slow, directed motion. This directional movement of labeled MreB in the growing polymer implies that treadmilling is the predominant mechanism in MreB filament formation. These single-molecule imaging experiments provide the first available information on the velocity of bacterial actin polymerization in a living cell.

  9. The bacterial cell cycle checkpoint protein Obg and its role in programmed cell death

    Directory of Open Access Journals (Sweden)

    Liselot Dewachter

    2016-03-01

    Full Text Available The phenomenon of programmed cell death (PCD, in which cells initiate their own demise, is not restricted to multicellular organisms. Unicellular organisms, both eukaryotes and prokaryotes, also possess pathways that mediate PCD. We recently identified a PCD mechanism in Escherichia coli that is triggered by a mutant isoform of the essential GTPase ObgE (Obg of E. coli. Importantly, the PCD pathway mediated by mutant Obg (Obg* differs fundamentally from other previously described bacterial PCD pathways and thus constitutes a new mode of PCD. ObgE was previously proposed to act as a cell cycle checkpoint protein able to halt cell division. The implication of ObgE in the regulation of PCD further increases the similarity between this protein and eukaryotic cell cycle regulators that are capable of doing both. Moreover, since Obg is conserved in eukaryotes, the elucidation of this cell death mechanism might contribute to the understanding of PCD in higher organisms. Additionally, if Obg*-mediated PCD is conserved among different bacterial species, it will be a prime target for the development of innovative antibacterials that artificially induce this pathway.

  10. Effects of a Protein Preload on Gastric Emptying, Glycemia, and Gut Hormones After a Carbohydrate Meal in Diet-Controlled Type 2 Diabetes

    OpenAIRE

    Ma, Jing; Stevens, Julie E.; Cukier, Kimberly; Maddox, Anne F.; Wishart, Judith M.; Jones, Karen L.; Clifton, Peter M.; Horowitz, Michael; Rayner, Christopher K.

    2009-01-01

    OBJECTIVE We evaluated whether a whey preload could slow gastric emptying, stimulate incretin hormones, and attenuate postprandial glycemia in type 2 diabetes. RESEARCH DESIGN AND METHODS Eight type 2 diabetic patients ingested 350 ml beef soup 30 min before a potato meal; 55 g whey was added to either the soup (whey preload) or potato (whey in meal) or no whey was given. RESULTS Gastric emptying was slowest after the whey preload (P < 0.0005). The incremental area under the blood glucose cur...

  11. Summer Meal Capacity Builder

    Data.gov (United States)

    Department of Agriculture — Allows users to search for summer meal sites from the previous summer by zip code, adding “layers” of information, such as free and reduced-price lunch participation...

  12. Avaliação do desempenho de coelhas alimentadas com farelo de canola em substituição parcial ou total ao farelo de soja Evaluation of the performance of female rabbits fed on canola meal in partial and total substitution of crude protein by soybean meal

    Directory of Open Access Journals (Sweden)

    Ivanor Nunes do Prado

    2001-05-01

    Full Text Available The effect of partial and total substitution of soybean meal crude protein (SBM by canola meal (CM on live weight (LW, daily weight gain (DWG, daily feed intake (DFI and feed conversion (FC in female rabbits are provided. Rabbits were evaluated from weaning period (43 days of age to adult life when they are capable of reproduction (150 days of age. Forty-eight White New Zealand females were used and distributed in four treatments. SBM was substituted at 00%, 33%, 66% and 100% levels by CM. The partial or total substitution of SBM by CM did not change (P > 0.05 the LW after 70 days old. Dunnett’s test showed that, independently of substitution level, FC of animals fed on meal with 33% SBM substitution by CM from age 43 to 90 days and 43 to 150 days was worse than that of animals fed on reference meal. LW120, DWG of 43 – 120-day-old animals receiving 33% SBM substitution by CM and LW150 and DWG of 43 – 150-day-old animals receiving meal with SBM substitution by 33% and 66% of CM were lower than those for animals that received reference meal. Excluding the reference meal, SBM substitution by CM during the periods in which animals were 43 - 120 days old and 43 - 150 days old caused an increase of DFI. Independently of level of inclusion as a substitute for SBM, results show that CM worsened the animals’ performance.Objetivando-se avaliar os efeitos da substiuição parcial e total do farelo de soja pelo farelo de canola sobre o peso, ganho médio diário (GMD, ingestão de alimentos (IA e conversão alimentar (CA em coelhas do desmame (43 dias até a idade de reprodução (150 dias, quarente e oito coelhas da raça Nova Zelândia, foram distribuídas, inteiramente ao acaso, em um experimento com quatro tratamentos e doze repetições. O farelo de soja foi substituído em 00, 33, 66 e 100% pelo farelo de canola. A substituição parcial ou total do farelo de soja não alterarou o peso após os 70 dias de idade. Por meio do uso do teste de

  13. Substituição parcial e total da proteína do farelo de soja pela proteína dos farelos de canola e algodão em dietas para alevinos de piavuçu, Leporinus macrocephalus (Garavello & Britski, 1988 Partial and total replacement of soybean meal protein by canola or cottonseed meal protein in diets of Leporinus macrocephalus (Garavello & Britski, 1988 fingerlings

    Directory of Open Access Journals (Sweden)

    Anna Christina Esper Amaro de Faria

    2001-05-01

    Full Text Available Com o objetivo de avaliar a substituição da proteína do farelo de soja (FS pela proteína do farelo de canola (FC e farelo de algodão (FA, em dietas para alevinos de piavuçu, Leporinus macrocephalus (Characiformes, Anostomidae, realizou-se um experimento com duração de 60 dias, utilizando-se 300 alevinos, com peso inicial médio de 0,10 g distribuídos em um delineamento em blocos casualizados, com seis tratamentos e cinco repetições. As dietas isoprotéicas foram formuladas de forma a terem o FS, FC, FA, FS+FC, FS+FA e FC+FA como fonte protéica. Os alevinos, alimentados com dietas contendo FS e FS+FA, apresentaram valores de peso final e taxa de eficiência protéica superiores (p 0,05 pelo uso das diferentes dietas. Observou-se redução linear dos valores de peso final, da taxa de eficiência protéica e aumento linear (p The effects of soybean meal (SB protein replacement by canola meal (CN or cottonseed meal (CT protein in diets of Leporinus macrocephalus (Characiformes, Anostomidae fingerlings are provided. Assay was carried out during 60 days. Three hundred fingerlings with mean initial weight of 1.00g were distributed in a block randomized design with six treatments and five replicates. Isoprotein diets contained SB, CN, CT, SB+CN, SB+CT and CN+CT as protein source. Fingerlings fed on diets with SB, SB+CN, SB+CT showed better final mean weight and protein efficiency rate values (p 0.05 by different diets linear reduction (p macrocephalus fingerlings, replacing 50.00% of SB protein.

  14. STUDIES ON THE BLOOD PROTEINS : I. THE SERUM GLOBULINS IN BACTERIAL INFECTION AND IMMUNITY.

    Science.gov (United States)

    Hurwitz, S H; Meyer, K F

    1916-11-01

    The progress of an infection is usually associated with marked changes in the serum proteins. There may be an increase in the percentage of the total protein during some stage of the infection, and there is usually a change in the albumin-globulin ratio with an increase in the total globulins. This rise may antedate the development of any resistance by a considerable period of time. The non-protein constituents of the blood show fluctuations with a tendency to rise as the infection progresses. The process of immunization is in almost all instances associated with a definite increase in the globulins of the blood, and in some cases with a complete inversion of the normal albumin-globulin ratio. This may be produced both by living and dead organisms and by bacterial endotoxins. Massive doses usually result in an upset which shows no tendency to right itself during the period of observation. A rise in the globulins has been shown to occur long before the animal develops immune bodies in any appreciable concentration; and where the globulin curve and antibody curve appear to parallel one another, it can be shown by a careful analysis of both curves that there is a definite lack of correspondence at various periods of the experiment. Animals possessing a basic immunity show a more rapid rise in the globulin curve following inoculation. There is no parallelism between the leukocytic reaction and the globulin reaction. During periods of leukopenia the globulins may be as high as during the period of a leukocytosis. Bacterial endotoxins produce as striking an increase in the serum globulins as do living and killed bacteria. This would seem to indicate that a bacterial invasion of the organism is not absolutely essential for the globulin changes, and that the toxogenic factor in infection and immunity must play a part in the production of the changes noted. Inflammatory irritants injected intraperitoneally also result in a globulin increase. In this case the changes

  15. Direct and Indirect Targeting of PP2A by Conserved Bacterial Type-III Effector Proteins.

    Directory of Open Access Journals (Sweden)

    Lin Jin

    2016-05-01

    Full Text Available Bacterial AvrE-family Type-III effector proteins (T3Es contribute significantly to the virulence of plant-pathogenic species of Pseudomonas, Pantoea, Ralstonia, Erwinia, Dickeya and Pectobacterium, with hosts ranging from monocots to dicots. However, the mode of action of AvrE-family T3Es remains enigmatic, due in large part to their toxicity when expressed in plant or yeast cells. To search for targets of WtsE, an AvrE-family T3E from the maize pathogen Pantoea stewartii subsp. stewartii, we employed a yeast-two-hybrid screen with non-lethal fragments of WtsE and a synthetic genetic array with full-length WtsE. Together these screens indicate that WtsE targets maize protein phosphatase 2A (PP2A heterotrimeric enzyme complexes via direct interaction with B' regulatory subunits. AvrE1, another AvrE-family T3E from Pseudomonas syringae pv. tomato strain DC3000 (Pto DC3000, associates with specific PP2A B' subunit proteins from its susceptible host Arabidopsis that are homologous to the maize B' subunits shown to interact with WtsE. Additionally, AvrE1 was observed to associate with the WtsE-interacting maize proteins, indicating that PP2A B' subunits are likely conserved targets of AvrE-family T3Es. Notably, the ability of AvrE1 to promote bacterial growth and/or suppress callose deposition was compromised in Arabidopsis plants with mutations of PP2A genes. Also, chemical inhibition of PP2A activity blocked the virulence activity of both WtsE and AvrE1 in planta. The function of HopM1, a Pto DC3000 T3E that is functionally redundant to AvrE1, was also impaired in specific PP2A mutant lines, although no direct interaction with B' subunits was observed. These results indicate that sub-component specific PP2A complexes are targeted by bacterial T3Es, including direct targeting by members of the widely conserved AvrE-family.

  16. Bacterial-based systems for expression and purification of recombinant Lassa virus proteins of immunological relevance

    Directory of Open Access Journals (Sweden)

    Cashman Kathleen A

    2008-06-01

    Full Text Available Abstract Background There is a significant requirement for the development and acquisition of reagents that will facilitate effective diagnosis, treatment, and prevention of Lassa fever. In this regard, recombinant Lassa virus (LASV proteins may serve as valuable tools in diverse antiviral applications. Bacterial-based systems were engineered for expression and purification of recombinant LASV nucleoprotein (NP, glycoprotein 1 (GP1, and glycoprotein 2 (GP2. Results Full-length NP and the ectodomains of GP1 and GP2 were generated as maltose-binding protein (MBP fusions in the Rosetta strains of Escherichia coli (E. coli using pMAL-c2x vectors. Average fusion protein yields per liter of culture for MBP-NP, MBP-GP1, and MBP-GP2 were 10 mg, 9 mg, and 9 mg, respectively. Each protein was captured from cell lysates using amylose resin, cleaved with Factor Xa, and purified using size-exclusion chromatography (SEC. Fermentation cultures resulted in average yields per liter of 1.6 mg, 1.5 mg, and 0.7 mg of purified NP, GP1 and GP2, respectively. LASV-specific antibodies in human convalescent sera specifically detected each of the purified recombinant LASV proteins, highlighting their utility in diagnostic applications. In addition, mouse hyperimmune ascitic fluids (MHAF against a panel of Old and New World arenaviruses demonstrated selective cross reactivity with LASV proteins in Western blot and enzyme-linked immunosorbent assay (ELISA. Conclusion These results demonstrate the potential for developing broadly reactive immunological assays that employ all three arenaviral proteins individually and in combination.

  17. Urokinase-targeted recombinant bacterial protein toxins-a rationally designed and engineered anticancer agent for cancer therapy

    Institute of Scientific and Technical Information of China (English)

    Yizhen LIU; Shi-Yan LI

    2009-01-01

    Urokinase-targeted recombinant bacterial protein toxins are a sort of rationally designed and engineered anticancer recombinant fusion proteins representing a novel class of agents for cancer therapy.Bacterial protein toxins have long been known as the primary virulence factor(s) for a variety of pathogenic bacteria and are the most powerful human poisons.On the other hand,it has been well documented that urokinase-type plasminogen activator (uPA) and urokinase plasminogen activator receptor (uPAR),making up the uPA system,are overexpressed in a variety of human tumors and tumor cell lines.The expression of uPA system is highly correlated with tumor invasion and metastasis.To exploit these characteristics in the design of tumor cell-selective cytotoxins,two prominent bacterial protein toxins,i.e.,the diphtheria toxin and anthrax toxin are deliberately engineered through placing a sequence targeted specifically by the uPA system to form anticancer recombinant fusion proteins.These uPA system-targeted bacterial protein toxins are activated selectively on the surface of uPA systemexpressing tumor cells,thereby killing these cells.This article provides a review on the latest progress in the exploitation of these recombinant fusion proteins as potent tumoricidal agents.It is perceptible that the strategies for cancer therapy are being innovated by this novel therapeutic approach.

  18. Growth Performance of Clarias Gariepinus Fed Soaked Moringa Oleifera Leaf Meal

    Directory of Open Access Journals (Sweden)

    Ayegba, E. O

    2016-06-01

    Full Text Available The present study evaluates the nutritional potential of soaked-dried Moringa oleifera leaf meal in the diet of Clarias gariepinus. Four isonitrogenous (35% crude protein diets were formulated with Moringa leaf replacing soybean meal at 0%, 10%, 20% and 30%. Result obtained revealed declined in weight gain, specific growth rate, feed conversion efficiency, protein efficiency ratio and apparent net protein utilization as dietary replacement of Moringa leaf meal increased beyond 10%. It is concluded that Moringa oleifera leaf meal can replace soybeans meal up to 10% without affecting the growth performance of African catfish.

  19. The Staphylococcus aureus extracellular adherence protein promotes bacterial internalization by keratinocytes independent of fibronectin-binding proteins.

    Science.gov (United States)

    Bur, Stephanie; Preissner, Klaus T; Herrmann, Mathias; Bischoff, Markus

    2013-08-01

    Staphylococcus aureus, the leading causal pathogen of skin infections, is strongly associated with skin atopy, and a number of bacterial adhesins allow the microbe to adhere to and invade eukaryotic cells. One of these adhesive molecules is the multifunctional extracellular adherence protein (Eap), which is overexpressed in situ in authentic human wounds and was shown to delay wound healing in experimental models. Yet, its role during invasion of keratinocytes is not clearly defined. By using a gentamicin/lysostaphin protection assay we demonstrate here that preincubation of HaCaT cells or primary keratinocytes with Eap results in a concentration-dependent significant increase in staphylococcal adhesion, followed by an even more pronounced internalization of bacteria by eukaryotic cells. Flow cytometric analysis revealed that Eap increased both the number of infected eukaryotic cells and the bacterial load per infected cell. Moreover, treatment of keratinocytes with Eap strongly enhanced the internalization of coagulase-negative staphylococci, as well as of E. coli, and markedly promoted staphylococcal invasion into extended-culture keratinocytes, displaying expression of keratin 10 and involucrin as differentiation markers. Thus, wound-related staphylococcal Eap may provide a major cellular invasin function, thereby enhancing the pathogen's ability to hide from the host immune system during acute and chronic skin infection.

  20. Fluorescence quenching as a tool to investigate quinolone antibiotic interactions with bacterial protein OmpF.

    Science.gov (United States)

    Neves, Patrícia; Sousa, Isabel; Winterhalter, Mathias; Gameiro, Paula

    2009-02-01

    The outer membrane porin OmpF is an important protein for the uptake of antibiotics through the outer membrane of gram-negative bacteria; however, the possible binding sites involved in this uptake are still not recognized. Determination, at the molecular level, of the possible sites of antibiotic interaction is very important, not only to understand their mechanism of action but also to unravel bacterial resistance. Due to the intrinsic OmpF fluorescence, attributed mainly to its tryptophans (Trp(214), Trp(61)), quenching experiments were used to assess the site(s) of interaction of some quinolone antibiotics. OmpF was reconstituted in different organized structures, and the fluorescence quenching results, in the presence of two quenching agents, acrylamide and iodide, certified that acrylamide quenches Trp(61) and iodide Trp(214). Similar data, obtained in presence of the quinolones, revealed distinct behaviors for these antibiotics, with nalidixic acid interacting near Trp(214) and moxifloxacin near Trp(61). These studies, based on straightforward and quick procedures, show the existence of conformational changes in the protein in order to adapt to the different organized structures and to interact with the quinolones. The extent of reorganization of the protein in the presence of the different quinolones allowed an estimate on the sites of protein/quinolone interaction.

  1. A functional interaction between ribosomal proteins S7 and S11 within the bacterial ribosome.

    Science.gov (United States)

    Robert, Francis; Brakier-Gingras, Léa

    2003-11-01

    In this study, we used site-directed mutagenesis to disrupt an interaction that had been detected between ribosomal proteins S7 and S11 in the crystal structure of the bacterial 30 S subunit. This interaction, which is located in the E site, connects the head of the 30 S subunit to the platform and is involved in the formation of the exit channel through which passes the 30 S-bound messenger RNA. Neither mutations in S7 nor mutations in S11 prevented the incorporation of the proteins into the 30 S subunits but they perturbed the function of the ribosome. In vivo assays showed that ribosomes with either mutated S7 or S11 were altered in the control of translational fidelity, having an increased capacity for frameshifting, readthrough of a nonsense codon and codon misreading. Toeprinting and filter-binding assays showed that 30 S subunits with either mutated S7 or S11 have an enhanced capacity to bind mRNA. The effects of the S7 and S11 mutations can be related to an increased flexibility of the head of the 30 S, to an opening of the mRNA exit channel and to a perturbation of the proposed allosteric coupling between the A and E sites. Altogether, our results demonstrate that S7 and S11 interact in a functional manner and support the notion that protein-protein interactions contribute to the dynamics of the ribosome.

  2. Structural and functional homology between periplasmic bacterial molecular chaperones and small heat shock proteins.

    Science.gov (United States)

    Zav'yalov, V P; Zav'yalova, G A; Denesyuk, A I; Gaestel, M; Korpela, T

    1995-07-01

    The periplasmic Yersinia pestis molecular chaperone Caf1M belongs to a superfamily of bacterial proteins for one of which (PapD protein of Escherichia coli) the immunoglobulin-like fold was solved by X-ray analysis. The N-terminal domain of Caf1M was found to share a 20% amino acid sequence identity with an inclusion body-associated protein IbpB of Escherichia coli. One of the regions that was compared, was 32 amino acids long, and displayed more than 40% identity, probability of random coincidence was 1.2 x 10(-4). IbpB is involved in a superfamily of small heat shock proteins which fulfil the function of molecular chaperone. On the basis of the revealed homology, an immunoglobulin-like one-domain model of IbpB three-dimensional structure was designed which could be a prototype conformation of sHsp's. The structure suggested is in good agreement with the known experimental data obtained for different members of sHsp's superfamily.

  3. Meals served in Danish nursing homes and to meals-on-wheels clients may not offer nutritionally adequate choices

    DEFF Research Database (Denmark)

    Beck, Anne Marie; Hansen, Kirsten S.

    2010-01-01

    ), extra portions of different menus were made (3 days in a row). The meal samples (total n = 389) were analyzed for content of energy, protein, fat and carbohydrate. The findings were compared with recommendations regarding the foods to be served in Danish institutions. The nutrient content of the meals...

  4. Evaluation of ultra-low Gossypol cottonseed and regular glandless cottonseed meals as dietary protein and lipid sources for Litopenaeus Vannamei reared under zero-exchange conditions

    Science.gov (United States)

    Our previous studies showed that glandless cottonseed meal (GCSM), produced from naturally occurring mutant plants, can replace 67-100% of fishmeal in shrimp diets without any negative effects on the growth and survival of shrimp. However, glandless cotton plants, completely lacking protective goss...

  5. Novel cyclic di-GMP effectors of the YajQ protein family control bacterial virulence.

    Science.gov (United States)

    An, Shi-qi; Caly, Delphine L; McCarthy, Yvonne; Murdoch, Sarah L; Ward, Joseph; Febrer, Melanie; Dow, J Maxwell; Ryan, Robert P

    2014-10-01

    Bis-(3',5') cyclic di-guanylate (cyclic di-GMP) is a key bacterial second messenger that is implicated in the regulation of many critical processes that include motility, biofilm formation and virulence. Cyclic di-GMP influences diverse functions through interaction with a range of effectors. Our knowledge of these effectors and their different regulatory actions is far from complete, however. Here we have used an affinity pull-down assay using cyclic di-GMP-coupled magnetic beads to identify cyclic di-GMP binding proteins in the plant pathogen Xanthomonas campestris pv. campestris (Xcc). This analysis identified XC_3703, a protein of the YajQ family, as a potential cyclic di-GMP receptor. Isothermal titration calorimetry showed that the purified XC_3703 protein bound cyclic di-GMP with a high affinity (K(d)∼2 µM). Mutation of XC_3703 led to reduced virulence of Xcc to plants and alteration in biofilm formation. Yeast two-hybrid and far-western analyses showed that XC_3703 was able to interact with XC_2801, a transcription factor of the LysR family. Mutation of XC_2801 and XC_3703 had partially overlapping effects on the transcriptome of Xcc, and both affected virulence. Electromobility shift assays showed that XC_3703 positively affected the binding of XC_2801 to the promoters of target virulence genes, an effect that was reversed by cyclic di-GMP. Genetic and functional analysis of YajQ family members from the human pathogens Pseudomonas aeruginosa and Stenotrophomonas maltophilia showed that they also specifically bound cyclic di-GMP and contributed to virulence in model systems. The findings thus identify a new class of cyclic di-GMP effector that regulates bacterial virulence.

  6. Novel cyclic di-GMP effectors of the YajQ protein family control bacterial virulence.

    Directory of Open Access Journals (Sweden)

    Shi-qi An

    2014-10-01

    Full Text Available Bis-(3',5' cyclic di-guanylate (cyclic di-GMP is a key bacterial second messenger that is implicated in the regulation of many critical processes that include motility, biofilm formation and virulence. Cyclic di-GMP influences diverse functions through interaction with a range of effectors. Our knowledge of these effectors and their different regulatory actions is far from complete, however. Here we have used an affinity pull-down assay using cyclic di-GMP-coupled magnetic beads to identify cyclic di-GMP binding proteins in the plant pathogen Xanthomonas campestris pv. campestris (Xcc. This analysis identified XC_3703, a protein of the YajQ family, as a potential cyclic di-GMP receptor. Isothermal titration calorimetry showed that the purified XC_3703 protein bound cyclic di-GMP with a high affinity (K(d∼2 µM. Mutation of XC_3703 led to reduced virulence of Xcc to plants and alteration in biofilm formation. Yeast two-hybrid and far-western analyses showed that XC_3703 was able to interact with XC_2801, a transcription factor of the LysR family. Mutation of XC_2801 and XC_3703 had partially overlapping effects on the transcriptome of Xcc, and both affected virulence. Electromobility shift assays showed that XC_3703 positively affected the binding of XC_2801 to the promoters of target virulence genes, an effect that was reversed by cyclic di-GMP. Genetic and functional analysis of YajQ family members from the human pathogens Pseudomonas aeruginosa and Stenotrophomonas maltophilia showed that they also specifically bound cyclic di-GMP and contributed to virulence in model systems. The findings thus identify a new class of cyclic di-GMP effector that regulates bacterial virulence.

  7. Molecular Characterization of Soybean Mosaic Virus NIa Protein and its Processing Event in Bacterial Expression

    Directory of Open Access Journals (Sweden)

    Bong K. Choi

    2006-01-01

    Full Text Available Soybean mosaic virus (SMV-CN18 is an Rsv resistance-breaking (RB isolate to overcome soybean resistance genes Rsv1, Rsv3 and Rsv4. The aim of this study was to characterize nuclear inclusion protein a (NIa protein of RB isolate at the molecular level and demonstrate its processing into genome-linked protein (VPg and NIa-Pro domains in Esherichia coli containing a bacterial expression pET vector inserted with NIa gene. The full-length of NIa gene was synthesized by reverse transcription-polymerase chain reaction (RT-PCR and its 1298 nucleotides (nt and 432 amino acids (aa were deduced. The nt and aa sequences of NIa gene of SMV-CN18 shared high identities with the corresponding sequences of the NIa gene of the known SMV isolates, suggesting that the NIa is a highly conserved protein. The NIa-Pro domain contains a highly conserved structural motif for proteolysis, while the VPg domain contains a nuclear localization signal (NLS, a putative NTP-binding site and cellular factor-binding sites. The phylogenetic tree revealed that less divergence of NIa protein exists among twelve SMV isolates, which can be supported by a low bootstrap value between clades. In addition, the full-length of NIa gene, amplified by RT-PCR, was ligated into pET-28b E. coli expression vector with an N-terminal His6-tag. Optimal conditions for expression were at 1mM treatment of IPTG at 25°C for 5 hr. The released protein from bacterial lysates remained soluble and proved the processing form of the NIa polyprotein. E. coli expression system shows the processed product of 29 kDa VPg in SDS-PAGE confirmed by western blot analysis in both crude extracts and purified elution products, using Ni2+-NTA resin. The present study indicates that the N-terminal region of NIa which is processed and expressed in bacteria.

  8. Remodeling a DNA-binding protein as a specific in vivo inhibitor of bacterial secretin PulD

    OpenAIRE

    Mouratou, Barbara; Schaeffer, Francis; Guilvout, Ingrid; Tello-Manigne, Diana; Pugsley, Anthony P.; Alzari, Pedro M.; Pecorari, Frédéric

    2007-01-01

    We engineered a class of proteins that binds selected polypeptides with high specificity and affinity. Use of the protein scaffold of Sac7d, belonging to a protein family that binds various ligands, overcomes limitations inherent in the use of antibodies as intracellular inhibitors: it lacks disulfide bridges, is small and stable, and can be produced in large amounts. An in vitro combinatorial/selection approach generated specific, high-affinity (up to 140 pM) binders against bacterial outer ...

  9. The host antimicrobial peptide Bac71-35 binds to bacterial ribosomal proteins and inhibits protein synthesis.

    Science.gov (United States)

    Mardirossian, Mario; Grzela, Renata; Giglione, Carmela; Meinnel, Thierry; Gennaro, Renato; Mergaert, Peter; Scocchi, Marco

    2014-12-18

    Antimicrobial peptides (AMPs) are molecules from innate immunity with high potential as novel anti-infective agents. Most of them inactivate bacteria through pore formation or membrane barrier disruption, but others cross the membrane without damages and act inside the cells, affecting vital processes. However, little is known about their intracellular bacterial targets. Here we report that Bac71-35, a proline-rich AMP belonging to the cathelicidin family, can reach high concentrations (up to 340 μM) inside the E. coli cytoplasm. The peptide specifically and completely inhibits in vitro translation in the micromolar concentration range. Experiments of incorporation of radioactive precursors in macromolecules with E. coli cells confirmed that Bac71-35 affects specifically protein synthesis. Ribosome coprecipitation and crosslinking assays showed that the peptide interacts with ribosomes, binding to a limited subset of ribosomal proteins. Overall, these results indicate that the killing mechanism of Bac71-35 is based on a specific block of protein synthesis.

  10. Stealth Proteins: In Silico Identification of a Novel Protein Family Rendering Bacterial Pathogens Invisible to Host Immune Defense.

    Directory of Open Access Journals (Sweden)

    2005-11-01

    Full Text Available There are a variety of bacterial defense strategies to survive in a hostile environment. Generation of extracellular polysaccharides has proved to be a simple but effective strategy against the host's innate immune system. A comparative genomics approach led us to identify a new protein family termed Stealth, most likely involved in the synthesis of extracellular polysaccharides. This protein family is characterized by a series of domains conserved across phylogeny from bacteria to eukaryotes. In bacteria, Stealth (previously characterized as SacB, XcbA, or WefC is encoded by subsets of strains mainly colonizing multicellular organisms, with evidence for a protective effect against the host innate immune defense. More specifically, integrating all the available information about Stealth proteins in bacteria, we propose that Stealth is a D-hexose-1-phosphoryl transferase involved in the synthesis of polysaccharides. In the animal kingdom, Stealth is strongly conserved across evolution from social amoebas to simple and complex multicellular organisms, such as Dictyostelium discoideum, hydra, and human. Based on the occurrence of Stealth in most Eukaryotes and a subset of Prokaryotes together with its potential role in extracellular polysaccharide synthesis, we propose that metazoan Stealth functions to regulate the innate immune system. Moreover, there is good reason to speculate that the acquisition and spread of Stealth could be responsible for future epidemic outbreaks of infectious diseases caused by a large variety of eubacterial pathogens. Our in silico identification of a homologous protein in the human host will help to elucidate the causes of Stealth-dependent virulence. At a more basic level, the characterization of the molecular and cellular function of Stealth proteins may shed light on fundamental mechanisms of innate immune defense against microbial invasion.

  11. Stealth proteins: in silico identification of a novel protein family rendering bacterial pathogens invisible to host immune defense.

    Directory of Open Access Journals (Sweden)

    Peter Sperisen

    2005-11-01

    Full Text Available There are a variety of bacterial defense strategies to survive in a hostile environment. Generation of extracellular polysaccharides has proved to be a simple but effective strategy against the host's innate immune system. A comparative genomics approach led us to identify a new protein family termed Stealth, most likely involved in the synthesis of extracellular polysaccharides. This protein family is characterized by a series of domains conserved across phylogeny from bacteria to eukaryotes. In bacteria, Stealth (previously characterized as SacB, XcbA, or WefC is encoded by subsets of strains mainly colonizing multicellular organisms, with evidence for a protective effect against the host innate immune defense. More specifically, integrating all the available information about Stealth proteins in bacteria, we propose that Stealth is a D-hexose-1-phosphoryl transferase involved in the synthesis of polysaccharides. In the animal kingdom, Stealth is strongly conserved across evolution from social amoebas to simple and complex multicellular organisms, such as Dictyostelium discoideum, hydra, and human. Based on the occurrence of Stealth in most Eukaryotes and a subset of Prokaryotes together with its potential role in extracellular polysaccharide synthesis, we propose that metazoan Stealth functions to regulate the innate immune system. Moreover, there is good reason to speculate that the acquisition and spread of Stealth could be responsible for future epidemic outbreaks of infectious diseases caused by a large variety of eubacterial pathogens. Our in silico identification of a homologous protein in the human host will help to elucidate the causes of Stealth-dependent virulence. At a more basic level, the characterization of the molecular and cellular function of Stealth proteins may shed light on fundamental mechanisms of innate immune defense against microbial invasion.

  12. A simple model for DNA bridging proteins and bacterial or human genomes: bridging-induced attraction and genome compaction

    Science.gov (United States)

    Johnson, J.; Brackley, C. A.; Cook, P. R.; Marenduzzo, D.

    2015-02-01

    We present computer simulations of the phase behaviour of an ensemble of proteins interacting with a polymer, mimicking non-specific binding to a piece of bacterial DNA or eukaryotic chromatin. The proteins can simultaneously bind to the polymer in two or more places to create protein bridges. Despite the lack of any explicit interaction between the proteins or between DNA segments, our simulations confirm previous results showing that when the protein-polymer interaction is sufficiently strong, the proteins come together to form clusters. Furthermore, a sufficiently large concentration of bridging proteins leads to the compaction of the swollen polymer into a globular phase. Here we characterise both the formation of protein clusters and the polymer collapse as a function of protein concentration, protein-polymer affinity and fibre flexibility.

  13. Making novel bio-interfaces through bacterial protein recrystallization on biocompatible polylactide derivative films

    Science.gov (United States)

    Lejardi, Ainhoa; López, Aitziber Eleta; Sarasua, José R.; Sleytr, U. B.; Toca-Herrera, José L.

    2013-09-01

    Fabrication of novel bio-supramolecular structures was achieved by recrystallizing the bacterial surface protein SbpA on amorphous and semicrystalline polylactide derivatives. Differential scanning calorimetry showed that the glass transition temperature (Tg) for (poly-L-lactide)-PLLA, poly(L,D-lactide)-PDLLA, poly(lactide-co-glycolide)-PLGA and poly(lactide-co-caprolactone)-PLCL was 63 °C, 53 °C, 49 °C and 15 °C, respectively. Tensile stress-strain tests indicated that PLLA, PLGA, and PDLLA had a glassy behaviour when tested below Tg. The obtained Young modulus were 1477 MPa, 1330 MPa, 1306 MPa, and 9.55 MPa for PLLA, PLGA, PDLLA, and PLCL, respectively. Atomic force microscopy results confirmed that SbpA recrystallized on every polymer substrate exhibiting the native S-layer P4 lattice (a = b = 13 nm, γ = 90°). However, the polymer substrate influenced the domain size of the S-protein crystal, with the smallest size for PLLA (0.011 μm2), followed by PDLLA (0.034 μm2), and PLGA (0.039 μm2), and the largest size for PLCL (0.09 μm2). quartz crystal microbalance with dissipation monitoring (QCM-D) measurements indicated that the adsorbed protein mass per unit area (˜1800 ng cm-2) was independent of the mechanical, thermal, and crystalline properties of the polymer support. The slowest protein adsorption rate was observed for amorphous PLCL (the polymer with the weakest mechanical properties and lowest Tg). QCM-D also monitored protein self-assembly in solution and confirmed that S-layer formation takes place in three main steps: adsorption, self-assembly, and crystal reorganization. Finally, this work shows that biodegradable polylactide derivatives films are a suitable support to form robust biomimetic S-protein layers.

  14. Making novel bio-interfaces through bacterial protein recrystallization on biocompatible polylactide derivative films.

    Science.gov (United States)

    Lejardi, Ainhoa; López, Aitziber Eleta; Sarasua, José R; Sleytr, U B; Toca-Herrera, José L

    2013-09-28

    Fabrication of novel bio-supramolecular structures was achieved by recrystallizing the bacterial surface protein SbpA on amorphous and semicrystalline polylactide derivatives. Differential scanning calorimetry showed that the glass transition temperature (T(g)) for (poly-L-lactide)-PLLA, poly(L,D-lactide)-PDLLA, poly(lactide-co-glycolide)-PLGA and poly(lactide-co-caprolactone)-PLCL was 63 °C, 53 °C, 49 °C and 15 °C, respectively. Tensile stress-strain tests indicated that PLLA, PLGA, and PDLLA had a glassy behaviour when tested below T(g). The obtained Young modulus were 1477 MPa, 1330 MPa, 1306 MPa, and 9.55 MPa for PLLA, PLGA, PDLLA, and PLCL, respectively. Atomic force microscopy results confirmed that SbpA recrystallized on every polymer substrate exhibiting the native S-layer P4 lattice (a = b = 13 nm, γ = 90°). However, the polymer substrate influenced the domain size of the S-protein crystal, with the smallest size for PLLA (0.011 μm(2)), followed by PDLLA (0.034 μm(2)), and PLGA (0.039 μm(2)), and the largest size for PLCL (0.09 μm(2)). quartz crystal microbalance with dissipation monitoring (QCM-D) measurements indicated that the adsorbed protein mass per unit area (~1800 ng cm(-2)) was independent of the mechanical, thermal, and crystalline properties of the polymer support. The slowest protein adsorption rate was observed for amorphous PLCL (the polymer with the weakest mechanical properties and lowest T(g)). QCM-D also monitored protein self-assembly in solution and confirmed that S-layer formation takes place in three main steps: adsorption, self-assembly, and crystal reorganization. Finally, this work shows that biodegradable polylactide derivatives films are a suitable support to form robust biomimetic S-protein layers.

  15. Effect of pH, salt and chemical rinses on bacterial attachment to extracellular matrix proteins.

    Science.gov (United States)

    Zulfakar, Siti Shahara; White, Jason D; Ross, Tom; Tamplin, Mark

    2013-06-01

    Microbial contamination of carcass surfaces occurs during slaughter and post-slaughter processing steps, therefore interventions are needed to enhance meat safety and quality. Although many studies have been done at the macro-level, little is known about specific processes that influence bacterial attachment to carcass surfaces, particularly the role of extracellular matrix (ECM) proteins. In the present study, the effect of pH and salt (NaCl, KCl and CaCl2) on attachment of Escherichia coli and Salmonella isolates to dominant ECM proteins: collagen I, fibronectin, collagen IV and laminin were assessed. Also, the effects of three chemical rinses commonly used in abattoirs (2% acetic acid, 2% lactic acid and 10% trisodium phosphate (TSP)) were tested. Within a pH range of 5-9, there was no significant effect on attachment to ECM proteins, whereas the effect of salt type and concentration varied depending on combination of strain and ECM protein. A concentration-dependant effect was observed with NaCl and KCl (0.1-0.85%) on attachment of E. coli M23Sr, but only to collagen I. One-tenth percent CaCl2 produced the highest level of attachment to ECM proteins for E. coli M23Sr and EC614. In contrast, higher concentrations of CaCl2 increased attachment of E. coli EC473 to collagen IV. Rinses containing TSP produced >95% reduction in attachment to all ECM proteins. These observations will assist in the design of targeted interventions to prevent or disrupt contamination of meat surfaces, thus improving meat safety and quality.

  16. LocateP: Genome-scale subcellular-location predictor for bacterial proteins

    Directory of Open Access Journals (Sweden)

    Zhou Miaomiao

    2008-03-01

    current tools especially where the N-terminally anchored and the SPIase-cleaved secreted proteins are concerned. Overall, the accuracy of LocateP was always higher than 90%. LocateP was then used to predict the SCLs of all proteins encoded by completed Gram-positive bacterial genomes. The results are stored in the database LocateP-DB http://www.cmbi.ru.nl/locatep-db1. Conclusion LocateP is by far the most accurate and detailed protein SCL predictor for Gram-positive bacteria currently available.

  17. Platform for identification of Salmonella serovar differentiating bacterial proteins by top-down mass spectrometry: S. Typhimurium vs S. Heidelberg.

    Science.gov (United States)

    McFarland, Melinda A; Andrzejewski, Denis; Musser, Steven M; Callahan, John H

    2014-07-15

    Intact protein expression profiling has proven to be a powerful tool for bacterial subspecies differentiation. To facilitate typing, epidemiology, and trace-back of Salmonella contamination in the food supply, a minimum of serovar level differentiation is required. Subsequent identification and validation of marker proteins is integral to rapid screening development and to determining which proteins are subject to environmental pressure. Bacterial sequencing efforts have expanded the number of sequenced genomes available for single-nucleotide polymorphism (SNP) analyses, but annotation is often missing, start site errors are not uncommon, and the likelihood of expression is not known. In this work we show that the combination of intact protein expression profiles and top-down liquid chromatography-mass spectrometry (LC-MS/MS) facilitates the identification of proteins that result from expressed serovar specific nonsynonymous SNPs. Combinations of these marker proteins can be used in assays for rapid differentiation of bacteria. LC-MS generated intact protein expression profiles establish which bacterial protein masses differ across samples and can be determined without prior knowledge of the sample. Subsequent top-down LC-MS/MS is used to identify expressed proteins and their post-translational modifications (PTM), identify serovar specific markers, and validate genomic predicted orthologues as expressed biomarkers.

  18. 植物蛋白源替代鱼粉对鱼类机体氧化胁迫的研究进展%Advances in the Effects of Dietary Substitution of Plant Protein Sources for Fish Meal on Oxidative Stress of Fish

    Institute of Scientific and Technical Information of China (English)

    姜海波

    2012-01-01

    合理的开发与利用植物蛋白源已成为解决鱼粉全球性缺乏的重要途径之一。较高比例的植物蛋白源会导致鱼体承受的氧化胁迫加剧,进而造成机体损伤,影响鱼类对植物蛋白源的利用效率。文章对已开展的研究结果进行归纳、分析与讨论,旨在为提高鱼类对植物蛋白源利用研究开拓新的思路。%Fish meal is the major source of animal protein in aquaculture diet, the increasing demand for fish meal by aquaculture industry makes fish meal become an increasingly expensive and limiting commodity. Therefore, it is necessary to find alternatives to partially or completely replace fish meal to make plant protein sources more affordable. Aiming to the potential application of plant protein sources for fish, the present paper summarized the oxidative stress caused by the dietary fish meal replacement practice. It is mentioned that the study about the dietary fish meal replacement for fish species served as an important way for the sustainability of aquaculture.

  19. Evaluation of millet residue meal based diets as feed for the domestic rabbit (Oryctolagus cuniculus

    Directory of Open Access Journals (Sweden)

    P. K. Karikari,

    2011-03-01

    Full Text Available This research evaluated the nutritive value of millet residue meal with fish meal, soybean meal or fish-soybean meal combination (1:2 as protein source. The treatments were labelled according to protein source as fish meal diet, soybean meal diet and fish-soybean meal diet. Thirty nulliparous mixed-breed rabbits of an initial mean (±SD body weight of 1852.6±122.7 g were used in a completely randomised design with 10 rabbits per treatment. The rabbits were allowed four weeks to adjust to the experimental diets before breeding was initiated. The feed intake during gestation and the reproductive data of the rabbits were assessed over two reproductive cycles. Does on the fish meal diet had poorer (P<0.05 DMI, daily growth rate and FCR than those on the soybean meal diet during the pre-breeding period. Does on the fish meal diet delivered less (P<0.05 number of kits at birth and weaned less kits compared to those on the soybean meal diet. Those on the soybean meal diet were heaviest (P<0.05 at mating and at kindling. They out-performed does on the fish meal diet in most of the parameters measured. Parity did not affect reproductive performance, but growth rate of the does had a positive linear relationship with DMI (r= 0.77; P<0.01 and a negative linear relationship with FCR (r= -0.83; P<0.01 during the pre-breeding period. It was concluded that millet residue meal may be a better feed source for rabbit does if soybean meal rather than fish meal or fish-soybean meal combination (1:2 is used to improve the protein content.

  20. Super Resolution Fluorescence Microscopy and Tracking of Bacterial Flotillin (Reggie Paralogs Provide Evidence for Defined-Sized Protein Microdomains within the Bacterial Membrane but Absence of Clusters Containing Detergent-Resistant Proteins.

    Directory of Open Access Journals (Sweden)

    Felix Dempwolff

    2016-06-01

    Full Text Available Biological membranes have been proposed to contain microdomains of a specific lipid composition, in which distinct groups of proteins are clustered. Flotillin-like proteins are conserved between pro-and eukaryotes, play an important function in several eukaryotic and bacterial cells, and define in vertebrates a type of so-called detergent-resistant microdomains. Using STED microscopy, we show that two bacterial flotillins, FloA and FloT, form defined assemblies with an average diameter of 85 to 110 nm in the model bacterium Bacillus subtilis. Interestingly, flotillin microdomains are of similar size in eukaryotic cells. The soluble domains of FloA form higher order oligomers of up to several hundred kDa in vitro, showing that like eukaryotic flotillins, bacterial assemblies are based in part on their ability to self-oligomerize. However, B. subtilis paralogs show significantly different diffusion rates, and consequently do not colocalize into a common microdomain. Dual colour time lapse experiments of flotillins together with other detergent-resistant proteins in bacteria show that proteins colocalize for no longer than a few hundred milliseconds, and do not move together. Our data reveal that the bacterial membrane contains defined-sized protein domains rather than functional microdomains dependent on flotillins. Based on their distinct dynamics, FloA and FloT confer spatially distinguishable activities, but do not serve as molecular scaffolds.

  1. Super Resolution Fluorescence Microscopy and Tracking of Bacterial Flotillin (Reggie) Paralogs Provide Evidence for Defined-Sized Protein Microdomains within the Bacterial Membrane but Absence of Clusters Containing Detergent-Resistant Proteins

    Science.gov (United States)

    Dempwolff, Felix; Schmidt, Felix K.; Hervás, Ana B.; Stroh, Alex; Rösch, Thomas C.; Riese, Cornelius N.; Dersch, Simon; Heimerl, Thomas; Lucena, Daniella; Hülsbusch, Nikola; Stuermer, Claudia A. O.; Takeshita, Norio; Fischer, Reinhard; Graumann, Peter L.

    2016-01-01

    Biological membranes have been proposed to contain microdomains of a specific lipid composition, in which distinct groups of proteins are clustered. Flotillin-like proteins are conserved between pro—and eukaryotes, play an important function in several eukaryotic and bacterial cells, and define in vertebrates a type of so-called detergent-resistant microdomains. Using STED microscopy, we show that two bacterial flotillins, FloA and FloT, form defined assemblies with an average diameter of 85 to 110 nm in the model bacterium Bacillus subtilis. Interestingly, flotillin microdomains are of similar size in eukaryotic cells. The soluble domains of FloA form higher order oligomers of up to several hundred kDa in vitro, showing that like eukaryotic flotillins, bacterial assemblies are based in part on their ability to self-oligomerize. However, B. subtilis paralogs show significantly different diffusion rates, and consequently do not colocalize into a common microdomain. Dual colour time lapse experiments of flotillins together with other detergent-resistant proteins in bacteria show that proteins colocalize for no longer than a few hundred milliseconds, and do not move together. Our data reveal that the bacterial membrane contains defined-sized protein domains rather than functional microdomains dependent on flotillins. Based on their distinct dynamics, FloA and FloT confer spatially distinguishable activities, but do not serve as molecular scaffolds. PMID:27362352

  2. Super Resolution Fluorescence Microscopy and Tracking of Bacterial Flotillin (Reggie) Paralogs Provide Evidence for Defined-Sized Protein Microdomains within the Bacterial Membrane but Absence of Clusters Containing Detergent-Resistant Proteins.

    Science.gov (United States)

    Dempwolff, Felix; Schmidt, Felix K; Hervás, Ana B; Stroh, Alex; Rösch, Thomas C; Riese, Cornelius N; Dersch, Simon; Heimerl, Thomas; Lucena, Daniella; Hülsbusch, Nikola; Stuermer, Claudia A O; Takeshita, Norio; Fischer, Reinhard; Eckhardt, Bruno; Graumann, Peter L

    2016-06-01

    Biological membranes have been proposed to contain microdomains of a specific lipid composition, in which distinct groups of proteins are clustered. Flotillin-like proteins are conserved between pro-and eukaryotes, play an important function in several eukaryotic and bacterial cells, and define in vertebrates a type of so-called detergent-resistant microdomains. Using STED microscopy, we show that two bacterial flotillins, FloA and FloT, form defined assemblies with an average diameter of 85 to 110 nm in the model bacterium Bacillus subtilis. Interestingly, flotillin microdomains are of similar size in eukaryotic cells. The soluble domains of FloA form higher order oligomers of up to several hundred kDa in vitro, showing that like eukaryotic flotillins, bacterial assemblies are based in part on their ability to self-oligomerize. However, B. subtilis paralogs show significantly different diffusion rates, and consequently do not colocalize into a common microdomain. Dual colour time lapse experiments of flotillins together with other detergent-resistant proteins in bacteria show that proteins colocalize for no longer than a few hundred milliseconds, and do not move together. Our data reveal that the bacterial membrane contains defined-sized protein domains rather than functional microdomains dependent on flotillins. Based on their distinct dynamics, FloA and FloT confer spatially distinguishable activities, but do not serve as molecular scaffolds.

  3. Cross-phosphorylation of bacterial serine/threonine and tyrosine protein kinases on key regulatory residues

    Directory of Open Access Journals (Sweden)

    Lei eShi

    2014-09-01

    Full Text Available Bacteria possess protein serine/threonine and tyrosine kinases which resemble eukaryal kinases in their capacity to phosphorylate multiple substrates. We hypothesized that the analogy might extend further, and bacterial kinases may also undergo mutual phosphorylation and activation, which is currently considered as a hallmark of eukaryal kinase networks. In order to test this hypothesis, we explored the capacity of all members of four different classes of serine/threonine and tyrosine kinases present in the firmicute model organism Bacillus subtilis to phosphorylate each other in vitro and interact with each other in vivo. The interactomics data suggested a high degree of connectivity among all types of kinases, while phosphorylation assays revealed equally wide-spread cross-phosphorylation events. Our findings suggest that the Hanks-type kinases PrkC, PrkD and YabT exhibit the highest capacity to phosphorylate other B. subtilis kinases, while the BY-kinase PtkA and the two-component-like kinases RsbW and SpoIIAB show the highest propensity to be phosphorylated by other kinases. Analysis of phosphorylated residues on several selected recipient kinases suggests that most cross-phosphorylation events concern key regulatory residues. Therefore, cross-phosphorylation events are very likely to influence the capacity of recipient kinases to phosphorylate substrates downstream in the signal transduction cascade. We therefore conclude that bacterial serine/threonine and tyrosine kinases probably engage in a network-type behavior previously described only in eukaryal cells.

  4. Structural reorganization of the bacterial cell-division protein FtsZ from Staphylococcus aureus.

    Science.gov (United States)

    Matsui, Takashi; Yamane, Junji; Mogi, Nobuyuki; Yamaguchi, Hiroto; Takemoto, Hiroshi; Yao, Min; Tanaka, Isao

    2012-09-01

    FtsZ is a key molecule in bacterial cell division. In the presence of GTP, it polymerizes into tubulin-like protofilaments by head-to-tail association. Protofilaments of FtsZ seem to adopt a straight or a curved conformation in relation to the bound nucleotide. However, although several bacterial and archaeal FtsZ structures have been determined, all of the structures reported previously are considered to have a curved conformation. In this study, structures of FtsZ from Staphylococcus aureus (SaFtsZ) were determined in apo, GDP-bound and inhibitor-complex forms and it was found that SaFtsZ undergoes marked conformational changes. The accumulated evidence suggests that the GDP-bound structure has the features of the straight form. The structural change between the curved and straight forms shows intriguing similarity to the eukaryotic cytoskeletal protein tubulin. Furthermore, the structure of the apo form showed an unexpectedly large conformational change in the core region. FtsZ has also been recognized as a novel target for antibacterial drugs. The structure of the complex with the inhibitor PC190723, which has potent and selective antistaphylococcal activity, indicated that the inhibitor binds at the cleft between the two subdomains.

  5. Malaria Vaccine Development: Are Bacterial Flagellin Fusion Proteins the Bridge between Mouse and Humans?

    Directory of Open Access Journals (Sweden)

    Daniel Y. Bargieri

    2011-01-01

    Full Text Available In the past 25 years, the development of an effective malaria vaccine has become one of the biggest riddles in the biomedical sciences. Experimental data using animal infection models demonstrated that it is possible to induce protective immunity against different stages of malaria parasites. Nonetheless, the vast body of knowledge has generated disappointments when submitted to clinical conditions and presently a single antigen formulation has progressed to the point where it may be translated into a human vaccine. In parallel, new means to increase the protective effects of antigens in general have been pursued and depicted, such as the use of bacterial flagellins as carriers/adjuvants. Flagellins activate pathways in the innate immune system of both mice and humans. The recent report of the first Phase I clinical trial of a vaccine containing a Salmonella flagellin as carrier/adjuvant may fuel the use of these proteins in vaccine formulations. Herein, we review the studies on the use of recombinant flagellins as vaccine adjuvants with malarial antigens in the light of the current state of the art of malaria vaccine development. The available information indicates that bacterial flagellins should be seriously considered for malaria vaccine formulations to the development of effective human vaccines.

  6. Communication: Microsecond dynamics of the protein and water affect electron transfer in a bacterial bc{sub 1} complex

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Daniel R.; Matyushov, Dmitry V., E-mail: dmitrym@asu.edu [Department of Physics and Department of Chemistry and Biochemistry, Arizona State University, P.O. Box 871504, Tempe, Arizona 85287 (United States)

    2015-04-28

    Cross-membrane electron transport between cofactors localized in proteins of mitochondrial respiration and bacterial photosynthesis is the source of all biological energy. The statistics and dynamics of nuclear fluctuations in these protein/membrane/water heterogeneous systems are critical for their energetic efficiency. The results of 13 μs of atomistic molecular dynamics simulations of the membrane-bound bc{sub 1} bacterial complex are analyzed here. The reaction is affected by a broad spectrum of nuclear modes, with the slowest dynamics in the range of time-scales ∼0.1-1.6 μs contributing half of the reaction reorganization energy. Two reorganization energies are required to describe protein electron transfer due to dynamical arrest of protein conformations on the observation window. This mechanistic distinction allows significant lowering of activation barriers for reactions in proteins.

  7. EXPRESSION OF BACTERIAL PROTEIN-A IN TOBACCO LEADS TO ENHANCED RESISTANCE TO STRESS CONDITIONS

    Directory of Open Access Journals (Sweden)

    Chaitali Roy

    2014-08-01

    Full Text Available Tobacco is the most commonly used plant for expression of transgenes from a variety of organisms because it can be easily grown and transformed, it provides abundant amounts of fresh tissue and has a well-established cell culture system. As bacterial enzymes can be synthesized in tobacco, here we explore the possibility of in planta expression of staphylococcal protein-A(PA which is an antibody, an important group among biopharmaceuticals. In our study we have shown that the tobacco plants harboring PA gene could combat the crown gall infection and also effective in resisting abiotic stress conditions. Transgenic plants when subjected to interact with wild variety of Agrobacterium shows its enhanced capability to resist the gall formation. And when transgenic tobacco plants were grown in presence of 200mM NaCl and/or MG(Methylglyoxal solution, shows their increased tolerance towards salinity stress and high MG stress. So far transgenic tobacco plants are concerned, improvements in the expression of recombinant proteins and their recovery from tobacco may also enhance production and commercial use of this protein.

  8. Structure-to-function relationships of bacterial translocator protein (TSPO: a focus on Pseudomonas

    Directory of Open Access Journals (Sweden)

    Charlène eLeneveu-Jenvrin

    2014-11-01

    Full Text Available The translocator protein (TSPO, which was previously designated as the peripheral-type benzodiazepine receptor, is a 3.5 billion year-old evolutionarily conserved protein expressed by most Eukarya, Archae and Bacteria, but its organization and functions differ remarkably. By taking advantage of the genomic data available on TSPO, we focused on bacterial TSPO and attempted to define functions of TSPO in Pseudomonas via in silico approaches. A tspo ortholog has been identified in several fluorescent Pseudomonas. This protein presents putative binding motifs for cholesterol and PK 11195, which is a specific drug ligand of mitochondrial TSPO. While it is a common surface distribution, the sense of insertion and membrane localization differ between α- and γ-proteobacteria. Experimental published data and STRING analysis of common TSPO partners in fluorescent Pseudomonas indicate a potential role of TSPO in the oxidative stress response, iron homeostasis and virulence expression. In these bacteria, TSPO could also take part in signal transduction and in the preservation of membrane integrity.

  9. Bacterial cytosolic proteins with a high capacity for Cu(I) that protect against copper toxicity

    Science.gov (United States)

    Vita, Nicolas; Landolfi, Gianpiero; Baslé, Arnaud; Platsaki, Semeli; Lee, Jaeick; Waldron, Kevin J.; Dennison, Christopher

    2016-12-01

    Bacteria are thought to avoid using the essential metal ion copper in their cytosol due to its toxicity. Herein we characterize Csp3, the cytosolic member of a new family of bacterial copper storage proteins from Methylosinus trichosporium OB3b and Bacillus subtilis. These tetrameric proteins possess a large number of Cys residues that point into the cores of their four-helix bundle monomers. The Csp3 tetramers can bind a maximum of approximately 80 Cu(I) ions, mainly via thiolate groups, with average affinities in the (1–2) × 1017 M‑1 range. Cu(I) removal from these Csp3s by higher affinity potential physiological partners and small-molecule ligands is very slow, which is unexpected for a metal-storage protein. In vivo data demonstrate that Csp3s prevent toxicity caused by the presence of excess copper. Furthermore, bacteria expressing Csp3 accumulate copper and are able to safely maintain large quantities of this metal ion in their cytosol. This suggests a requirement for storing copper in this compartment of Csp3-producing bacteria.

  10. Symmetry and scale orient Min protein patterns in shaped bacterial sculptures

    Science.gov (United States)

    Wu, Fabai; van Schie, Bas G. C.; Keymer, Juan E.; Dekker, Cees

    2015-08-01

    The boundary of a cell defines the shape and scale of its subcellular organization. However, the effects of the cell's spatial boundaries as well as the geometry sensing and scale adaptation of intracellular molecular networks remain largely unexplored. Here, we show that living bacterial cells can be ‘sculpted’ into defined shapes, such as squares and rectangles, which are used to explore the spatial adaptation of Min proteins that oscillate pole-to-pole in rod-shaped Escherichia coli to assist cell division. In a wide geometric parameter space, ranging from 2 × 1 × 1 to 11 × 6 × 1 μm3, Min proteins exhibit versatile oscillation patterns, sustaining rotational, longitudinal, diagonal, stripe and even transversal modes. These patterns are found to directly capture the symmetry and scale of the cell boundary, and the Min concentration gradients scale with the cell size within a characteristic length range of 3-6 μm. Numerical simulations reveal that local microscopic Turing kinetics of Min proteins can yield global symmetry selection, gradient scaling and an adaptive range, when and only when facilitated by the three-dimensional confinement of the cell boundary. These findings cannot be explained by previous geometry-sensing models based on the longest distance, membrane area or curvature, and reveal that spatial boundaries can facilitate simple molecular interactions to result in far more versatile functions than previously understood.

  11. Decreased Bacterial Attachment and Protein Adsorption to Coatings Produced by Low Enegy Plasma Polymerization

    DEFF Research Database (Denmark)

    Andersen, T.E.; Kingshott, Peter; Benter, M.

    with a surface less prone to the adsorption of biological matter. In the current study two different hydrophilic nanoscale coatings were produced by low energy plasma polymerization [3] and investigated· f()rl()w ... pr()tein adsorption and bacterial attachment properties. Methods were setup to enable...... and Methods: Coatings: Plasma polymerized poly(vinyl pyrrolidone) (PP-PVP), poly(2-methoxyethyl methacrylate) (PPPMEA) or an inorganic oxide (10) coating were applied onto medical grade silicon rubber sheets (Silopren LSR 2050, Momentive Performance Materials Inc.). Plasma polymerization chamber......-coated crystals were then treated with one of the plasma polymerized coatings. Adsorption of fibrinogen, human serum albumin or immunoglobulin G was measured using a QCM-D instrument [5] (model E4, Q-Sense AB, Vastra Frolunda, Sweden) using a solution of 50llg/1 protein in PBS buffer. Results and Discussion: Our...

  12. Stainless steel modified with poly(ethylene glycol) can prevent protein adsorption but not bacterial adhesion

    DEFF Research Database (Denmark)

    Wei, Jiang; Bagge, Dorthe; Gram, Lone

    2003-01-01

    by the adsorption of branched poly(ethylenimine) (PEI) from water. Methoxy-terminated aldehyde-poly(ethylene glycol) (M-PEG-CHO) was then grafted onto the PEI layers using reductive amination at the lower critical solution temperature (LCST) of the PEG in order to optimize the graft density of the linear PEG chains......The surface of AISI 316 grade stainless steel (SS) was modified with a layer of poly(ethylene glycol) (PEG) (molecular weight 5000) with the aim of preventing protein adsorption and bacterial adhesion. Model SS substrates were first modified to introduce a very high density of reactive amine groups....... The chemical composition and uniformity of the surfaces were determined using X-ray photoelectron spectroscopy (XPS) and time-of-flight static secondary ion mass spectrometry (ToF-SSIMS) in the imaging mode. The effects of PEI concentration and different substrate pre-cleaning methods on the structure...

  13. Temporal expression of bacterial proteins instructs host CD4 T cell expansion and Th17 development.

    Directory of Open Access Journals (Sweden)

    Seung-Joo Lee

    2012-01-01

    Full Text Available Pathogens can substantially alter gene expression within an infected host depending on metabolic or virulence requirements in different tissues, however, the effect of these alterations on host immunity are unclear. Here we visualized multiple CD4 T cell responses to temporally expressed proteins in Salmonella-infected mice. Flagellin-specific CD4 T cells expanded and contracted early, differentiated into Th1 and Th17 lineages, and were enriched in mucosal tissues after oral infection. In contrast, CD4 T cells responding to Salmonella Type-III Secretion System (TTSS effectors steadily accumulated until bacterial clearance was achieved, primarily differentiated into Th1 cells, and were predominantly detected in systemic tissues. Thus, pathogen regulation of antigen expression plays a major role in orchestrating the expansion, differentiation, and location of antigen-specific CD4 T cells in vivo.

  14. Evaluate the effect of mutans Aspergillus niger to the nutritive value of fermentation at coconut meal and karnel palm meal

    Directory of Open Access Journals (Sweden)

    TRESNAWATI PURWADARIA

    2004-07-01

    Full Text Available Agricultural wastes, such as coconut meal and kernel palm meal can be used to fulfill the need of feed for ruminants or monogastrics. Fermentation technology using Aspergillus niger has been reported allow to increase their nutritive value. Isolation of the asporogenous strain which could spored at room temperature but could not spored at 37oC is expected to sole the fermentation of spores in the fermentation product. The spore formation of mutants at the fourth day incubation time (10% was less than the wild type (100%. The variance analysis of protein content in vitro Dry Matter Digestibility (IVDMD and in vitro Protein Digestibility (IVPD showed that the kind of mutants were interacted with the incubation time (P<0,01. The highest protein content of coconut meal was obtained from E27 mutant (33.0%, kernel palm meal was obtained from E14 mutant (31.4% at the fourth day of incubation time. The highest IVDMD of coconut meal (62.1%, kernel palms meal (61.8% at the fourth day incubation time and from all E27 mutant. The highest IVPD of coconut meal was obtained from E27 mutant (20.49% at the fourth day incubation time, kernel palm meal was obtained from E27 mutant (18.66% at the fourth days incubation time.

  15. Studies of fish meal in aquafeeds%鱼粉在水产饲料中的应用研究

    Institute of Scientific and Technical Information of China (English)

    杨勇; 解绶启; 刘建康

    2004-01-01

    As a main protein source in aquafeeds, fish meal has been extensively studied. Fish sources, freshness, processing temperature, lipid quality and microbiological index are five main aspects of the evaluation of fish meal quality. This paper reviewed the researches on fish meal including the evaluation of fish meal quality, the use of fishmeal and the environmental problems. Biogenic amine is the main potential toxin in decomposed fish meal including mainly histamine, cadaverine, putrescine and tyramine and most studies showed that they could affect the fish growth performance and health. The determination of protein digestibility of fish meal includes pepsin-digestion method, animal test, capillary electrophoresis, etc. The content of phosphorus in fish meal and its utilization can introduce pollution to water bodies and the use of alternative protein and improvement of utilization of fish meal can help to reduce the pollution from fish meal.

  16. Meals in nursing homes

    DEFF Research Database (Denmark)

    Kofod, Jens Erik; Birkemose, A.

    2004-01-01

    Undernutrition is present among 33% of nursing home residents in Denmark. Hence, it is relevant to examine the meal situation at nursing homes to single out factors that may increase or reduce the residents' food intake. in the ongoing Danish nursing home debate it is claimed that a new type...... of nursing home improves the residents' meal situation with a positive effect on nutrition. The aim of this work is to test the general hypothesis that (i) residents appreciate the meal situation in these nursing homes and (ii) nutritional status of the residents is improved in this type of nursing home....... This study was carried out in four Danish nursing homes at various locations in Denmark. The methods used are qualitative interviews and observations at four nursing homes in combination with measurement of body mass index (BMI) at two of the four nursing homes. Undernutrition is defined as a BMI below 20...

  17. Phosphorus reduction by sifting fish waste meal

    Directory of Open Access Journals (Sweden)

    Ronaldo Lima de Lima

    2014-10-01

    Full Text Available Fish meal is widely included in animal feed because it contains ideal essential amino acids profile, it is rich in energy, essential fatty acids, vitamins and minerals and with >80% apparent protein digestibility in peneid shrimp. In human nutrition, studies are investigating the inclusion of fish meal in snacks, cakes, breads and cookies, as an enrichment in calcium, phosphorus, iron, protein and, especially, omega-3 fatty acids. Omega-3 fatty acids reduces heart diseases and have antithrombotic and anti-inflammatory properties (eicosapentaenoic acid, and are essential to the formation of brain tissue and retina in infants and are important during pregnancy and lactation (docosahexaenoic acid. Fish meal produced from fish waste is rich in minerals (phosphorus, which may cause eutrophication and impair water quality in aquaculture. The aim of this study was to reduce phosphorus content from commercial fish meal produced from waste by sifting (0.60 - 1.00 - 1.18 - 1.40 - 2.36 and 3.35mm mesh sizes. Fish meal samples were collected monthly for 24 months. Proximate composition of subsamples per mesh size was compared to the unsieved sample. Results indicate that sifting through a 0.60mm sieve total phosphorus and ash contents were reduced up to 32% and 36%, respectively, further to increase protein content up to 20%. Average composition of the subsamples was 47.04% ash, 5.56% of total phosphorus and 39.45% protein, suggesting that the residue of the fractionation may be marketed as a mineral and protein supplement.

  18. A bacterial view of the periodic table: genes and proteins for toxic inorganic ions.

    Science.gov (United States)

    Silver, Simon; Phung, Le T

    2005-12-01

    Essentially all bacteria have genes for toxic metal ion resistances and these include those for Ag+, AsO2-, AsO4(3-), Cd2+ Co2+, CrO4(2-), Cu2+, Hg2+, Ni2+, Pb2+, TeO3(2-), Tl+ and Zn2+. The largest group of resistance systems functions by energy-dependent efflux of toxic ions. Fewer involve enzymatic transformations (oxidation, reduction, methylation, and demethylation) or metal-binding proteins (for example, metallothionein SmtA, chaperone CopZ and periplasmic silver binding protein SilE). Some of the efflux resistance systems are ATPases and others are chemiosmotic ion/proton exchangers. For example, Cd2+-efflux pumps of bacteria are either inner membrane P-type ATPases or three polypeptide RND chemiosmotic complexes consisting of an inner membrane pump, a periplasmic-bridging protein and an outer membrane channel. In addition to the best studied three-polypeptide chemiosmotic system, Czc (Cd2+, Zn2+, and Co2), others are known that efflux Ag+, Cu+, Ni2+, and Zn2+. Resistance to inorganic mercury, Hg2+ (and to organomercurials, such as CH3Hg+ and phenylmercury) involve a series of metal-binding and membrane transport proteins as well as the enzymes mercuric reductase and organomercurial lyase, which overall convert more toxic to less toxic forms. Arsenic resistance and metabolizing systems occur in three patterns, the widely-found ars operon that is present in most bacterial genomes and many plasmids, the more recently recognized arr genes for the periplasmic arsenate reductase that functions in anaerobic respiration as a terminal electron acceptor, and the aso genes for the periplasmic arsenite oxidase that functions as an initial electron donor in aerobic resistance to arsenite.

  19. Engineered Bacterial Metal-binding Proteins for Nanoscale Self-assembly and heavy Metal Tolerance

    Science.gov (United States)

    Hall Sedlak, Ruth Amanda

    Implementing biological principles in material synthesis and assembly is one way to expand our abilities to efficiently assemble nanoscale materials and devices. Specifically, recent advances in identifying peptides that bind inorganic materials with high affinity and specificity has spurred investigation of protein models for nanoscale inorganic assembly. This dissertation presents the results of my studies of several E. coli proteins engineered to bind inorganic materials through simple peptide motifs. I demonstrate that these proteins modulate the self-assembly of DNA-based nanostructures and can introduce heavy metal tolerance into metal-sensitive bacteria. Chapter 2 explores use of the engineered F plasmid DNA relaxase/helicase TraI for the self-assembly of complex DNA-protein-gold nanostructures. The full-length protein is engineered with a gold binding motif at an internal permissive site (TraI369GBP1-7x), while a truncated version of TraI is engineered with the same gold binding motif at the C-terminus (TraI361GBP1-7x). Both constructs bind gold nanoparticles while maintaining their DNA binding activity, and transmission electron microscopy reveals TraI369GBP1-7x utilizes its non-specific DNA binding activity to decorate single-stranded and double-stranded DNA with gold nanoparticles. The self assembly principles demonstrated in this work will be fundamental to constructing higher ordered hybrid nanostructures through DNA-protein-nanoparticle interactions. Chapter 3 studies the effects of expressing inorganic binding peptides within cells. I identified a silver binding peptide that, when fused to the periplasmic maltose binding protein, protects E. coli from silver toxicity in batch culture and reduces silver ions to silver nanoparticles within the bacterial periplasm. Engineered metal-ion tolerant microorganisms such as this E. coli could potentially be used in applications ranging from remediation to interrogation of biomolecule-metal interactions in vivo

  20. Effect of uncoupler on assembly pathway for pigment-binding protein of bacterial photosynthetic membranes. [Rhodobacter capsulatus

    Energy Technology Data Exchange (ETDEWEB)

    Dierstein, R.; Drews, G.

    1986-10-01

    The uncoupler carbonylcyanide m-chlorophenylhydrazone (CCCP) was used to investigate membrane protein assembly in the phototrophic bacterium Rhodobacter capsulatus. As found for Escherichia coli and mitochondrial proteins, assembly across the bacterial photosynthetic membranes was sensitive to CCCP. At uncoupler concentrations which were sufficient to block the export of the periplasmic cytochrome c/sub 2/ and an outer membrane protein, the integration of pigment-binding protein into the photosynthetic apparatus was abolished. The unassembled protein was detected on the inner surface of the intracytoplasmic membrane. After inactivation of CCCP, accumulated protein continued insertion into the membrane. The data suggest that after binding to the cytoplasmic face of the membrane (i), translocation of protein into a transmembrane orientation takes place (ii), which is a prerequisite for the formation of a functional pigment-protein complex (iii).

  1. The structure of SAV1646 from Staphylococcus aureus belonging to a new `ribosome-associated' subfamily of bacterial proteins.

    Science.gov (United States)

    Chirgadze, Yuri N; Clarke, Teresa E; Romanov, Vladimir; Kisselman, Gera; Wu-Brown, Jean; Soloveychik, Maria; Chan, Tiffany S Y; Gordon, Roni D; Battaile, Kevin P; Pai, Emil F; Chirgadze, Nickolay Y

    2015-02-01

    The crystal structure of the SAV1646 protein from the pathogenic microorganism Staphylococcus aureus has been determined at 1.7 Å resolution. The 106-amino-acid protein forms a two-layer sandwich with α/β topology. The protein molecules associate as dimers in the crystal and in solution, with the monomers related by a pseudo-twofold rotation axis. A sequence-homology search identified the protein as a member of a new subfamily of yet uncharacterized bacterial `ribosome-associated' proteins with at least 13 members to date. A detailed analysis of the crystal protein structure along with the genomic structure of the operon containing the sav1646 gene allowed a tentative functional model of this protein to be proposed. The SAV1646 dimer is assumed to form a complex with ribosomal proteins L21 and L27 which could help to complete the assembly of the large subunit of the ribosome.

  2. A man-made ATP-binding protein evolved independent of nature causes abnormal growth in bacterial cells.

    Directory of Open Access Journals (Sweden)

    Joshua M Stomel

    Full Text Available Recent advances in de novo protein evolution have made it possible to create synthetic proteins from unbiased libraries that fold into stable tertiary structures with predefined functions. However, it is not known whether such proteins will be functional when expressed inside living cells or how a host organism would respond to an encounter with a non-biological protein. Here, we examine the physiology and morphology of Escherichia coli cells engineered to express a synthetic ATP-binding protein evolved entirely from non-biological origins. We show that this man-made protein disrupts the normal energetic balance of the cell by altering the levels of intracellular ATP. This disruption cascades into a series of events that ultimately limit reproductive competency by inhibiting cell division. We now describe a detailed investigation into the synthetic biology of this man-made protein in a living bacterial organism, and the effect that this protein has on normal cell physiology.

  3. Diabetes type 2 - meal planning

    Science.gov (United States)

    ... ency/article/007429.htm Diabetes type 2 - meal planning To use the sharing features on this page, ... foods have carbohydrates. This will help with meal planning so that you can keep your blood sugar ...

  4. Research on the production of compound protein powder by mixed strain fermentation of soybean meal%混合菌株发酵豆粕生产复合蛋白粉研究

    Institute of Scientific and Technical Information of China (English)

    张艳; 崔青曼; 袁春营; 王英光

    2012-01-01

    Six experimental groups were designed with shrimp shell fermentation liquid and soybean as raw materials according to several factors affecting fermentation effect,fermentation effect of different treatment groups were compared by measuring the range of indicators, the results showed that: fermented soybean meal (compound protein powder )compared with raw meal,the former had wine, sensory good, strong acid flavor, trypsin inhibitor and phytic acid content decreased significantly(P<0.05), soluble protein, free amino acid, peptide content increased significantly (P<0.05), protein content increased significantly (P<0.05), it was illustrated that nutritional value of soybean meal had been greatly improved by mixed fermentation. The fifth experimental group was the best in all the experimental groups, fermentation parameters of the group: fermented liquor pH value was 6.5, added the non-sterilized soybean meal, solid-liquid ratio was 1 : 1.8, yeast inoculation quantity was 15% of soybean meal quality,10% glucose of soybean meal quality was added after 12 h fermentation,fermentation temperature was 35 t,fermentation time was 48 h.%以虾壳发酵液和豆粕为原料,根据影响发酵效果的几个因素,设计6组实验,通过测定系列指标,比较不同处理组豆粕的发酵效果.结果表明,发酵豆粕(复合蛋白粉)与原料豆粕相比,感官良好,带有酒香的浓郁酸香味,胰蛋白酶抑制因子和植酸含量显著降低(P<0.05),酸溶蛋白、游离氨基酸、小肽含量显著升高(P<0.05),蛋白质含量显著升高(P<0.05),说明经过混菌发酵,豆粕的营养价值得到极大提高.在各实验组中,以实验5组效果最佳,该组的发酵参数是:发酵原液·pH值6.5,添加未灭菌豆粕,料液比为1:1.8,酿酒酵母接菌量为豆粕质量的15%,发酵后12 h添加豆粕质量10%的葡萄糖,发酵温度35℃,发酵时间48 h.

  5. Traditional processing treatments as a promising approach To enhance the functional properties of rapeseed (Brassica campestris var. toria) and sesame seed (Sesamum indicum) meals.

    Science.gov (United States)

    Mahajan, A; Bhardwaj, S; Dua, S

    1999-08-01

    Different processing treatments were applied to rapeseed and sesame seed meals, and the functional properties of these products were assessed. All treatments except puffing for both meals and pressure cooking in sesame meal increased water absorption capacity (WAC). Fat absorption capacity (FAC) of rapeseed meals was enhanced significantly by all treatments. The full-fat meals of both sources showed maximum protein solubility when fermented and minimum protein solubility when pressure-cooked. Germinated and microwave-cooked meals enhanced foaming properties of rapeseed meals. Heat treatments, except microwave cooking, considerably reduced emulsifying properties of both meals. Fermentation and germination increased the specific viscosity of rapeseed meals, whereas processed sesame meals showed lower viscosity than dry sesame meals.

  6. Optimization of Mutation Pressure in Relation to Properties of Protein-Coding Sequences in Bacterial Genomes.

    Directory of Open Access Journals (Sweden)

    Paweł Błażej

    Full Text Available Most mutations are deleterious and require energetically costly repairs. Therefore, it seems that any minimization of mutation rate is beneficial. On the other hand, mutations generate genetic diversity indispensable for evolution and adaptation of organisms to changing environmental conditions. Thus, it is expected that a spontaneous mutational pressure should be an optimal compromise between these two extremes. In order to study the optimization of the pressure, we compared mutational transition probability matrices from bacterial genomes with artificial matrices fulfilling the same general features as the real ones, e.g., the stationary distribution and the speed of convergence to the stationarity. The artificial matrices were optimized on real protein-coding sequences based on Evolutionary Strategies approach to minimize or maximize the probability of non-synonymous substitutions and costs of amino acid replacements depending on their physicochemical properties. The results show that the empirical matrices have a tendency to minimize the effects of mutations rather than maximize their costs on the amino acid level. They were also similar to the optimized artificial matrices in the nucleotide substitution pattern, especially the high transitions/transversions ratio. We observed no substantial differences between the effects of mutational matrices on protein-coding sequences in genomes under study in respect of differently replicated DNA strands, mutational cost types and properties of the referenced artificial matrices. The findings indicate that the empirical mutational matrices are rather adapted to minimize mutational costs in the studied organisms in comparison to other matrices with similar mathematical constraints.

  7. Third order nonlinear optical properties of stacked bacteriochlorophylls in bacterial photosynthetic light-harvesting proteins

    Energy Technology Data Exchange (ETDEWEB)

    Chen, L.X.; Laible, P.D. [Argonne National Lab., IL (United States). Chemistry Div.; Spano, F.C.; Manas, E.S. [Temple Univ., Philadelphia, PA (United States). Dept. of Chemistry

    1997-09-01

    Enhancement of the nonresonant second order molecular hyperpolarizabilities {gamma} were observed in stacked macrocyclic molecular systems, previously in a {micro}-oxo silicon phthalocyanine (SiPcO) monomer, dimer and trimer series, and now in bacteriochlorophyll a (BChla) arrays of light harvesting (LH) proteins. Compared to monomeric BChla in a tetrahydrofuran (THF) solution, the <{gamma}> for each macrocycle was enhanced in naturally occurring stacked macrocyclic molecular systems in the bacterial photosynthetic LH proteins where BChla`s are arranged in tilted face-to-face arrays. In addition, the {gamma} enhancement is more significant in B875 of LH1 than in B850 in LH2. Theoretical modeling of the nonresonant {gamma} enhancement using simplified molecular orbitals for model SiPcO indicated that the energy level of the two photon state is crucial to the {gamma} enhancement when a two photon process is involved, whereas the charge transfer between the monomers is largely responsible when one photon near resonant process is involved. The calculated results can be extended to {gamma} enhancement in B875 and B850 arrays, suggesting that BChla in B875 are more strongly coupled than in B850. In addition, a 50--160 fold increase in <{gamma}> for the S{sub 1} excited state of relative to S{sub 0} of bacteriochlorophyll in vivo was observed which provides an alternative method for probing excited state dynamics and a potential application for molecular switching.

  8. Optimization of Mutation Pressure in Relation to Properties of Protein-Coding Sequences in Bacterial Genomes.

    Science.gov (United States)

    Błażej, Paweł; Miasojedow, Błażej; Grabińska, Małgorzata; Mackiewicz, Paweł

    2015-01-01

    Most mutations are deleterious and require energetically costly repairs. Therefore, it seems that any minimization of mutation rate is beneficial. On the other hand, mutations generate genetic diversity indispensable for evolution and adaptation of organisms to changing environmental conditions. Thus, it is expected that a spontaneous mutational pressure should be an optimal compromise between these two extremes. In order to study the optimization of the pressure, we compared mutational transition probability matrices from bacterial genomes with artificial matrices fulfilling the same general features as the real ones, e.g., the stationary distribution and the speed of convergence to the stationarity. The artificial matrices were optimized on real protein-coding sequences based on Evolutionary Strategies approach to minimize or maximize the probability of non-synonymous substitutions and costs of amino acid replacements depending on their physicochemical properties. The results show that the empirical matrices have a tendency to minimize the effects of mutations rather than maximize their costs on the amino acid level. They were also similar to the optimized artificial matrices in the nucleotide substitution pattern, especially the high transitions/transversions ratio. We observed no substantial differences between the effects of mutational matrices on protein-coding sequences in genomes under study in respect of differently replicated DNA strands, mutational cost types and properties of the referenced artificial matrices. The findings indicate that the empirical mutational matrices are rather adapted to minimize mutational costs in the studied organisms in comparison to other matrices with similar mathematical constraints.

  9. Surface-modified nanoparticles as a new, versatile, and mechanically robust nonadhesive coating: Suppression of protein adsorption and bacterial adhesion

    NARCIS (Netherlands)

    Holmes, P.F.; Currie, E.P.K.; Thies, J.C.; Mei, van der H.C.; Busscher, H.J.; Norde, W.

    2009-01-01

    The synthesis of surface-modified silica nanoparticles, chemically grafted with acrylate and poly(ethylene glycol) (PEG) groups, and the ability of the resulting crosslinked coatings to inhibit protein adsorption and bacterial adhesion are explored. Water contact angles, nanoindentation, and atomic

  10. Surface-modified nanoparticles as a new, versatile, and mechanically robust nonadhesive coating : Suppression of protein adsorption and bacterial adhesion

    NARCIS (Netherlands)

    Holmes, P. F.; Currie, E. P. K.; Thies, J. C.; van der Mei, H. C.; Busscher, H. J.; Norde, W.

    2009-01-01

    The synthesis of surface-modified silica nanoparticles, chemically grafted with acrylate and poly(ethylene glycol) (PEG) groups, and the ability of the resulting crosslinked coatings to inhibit protein adsorption and bacterial adhesion are explored. Water contact angles, nanoindentation, and atomic

  11. Development of Phage-Based Antibody Fragment Reagents for Affinity Enrichment of Bacterial Immunoglobulin G Binding Proteins.

    Science.gov (United States)

    Säll, Anna; Sjöholm, Kristoffer; Waldemarson, Sofia; Happonen, Lotta; Karlsson, Christofer; Persson, Helena; Malmström, Johan

    2015-11-06

    Disease and death caused by bacterial infections are global health problems. Effective bacterial strategies are required to promote survival and proliferation within a human host, and it is important to explore how this adaption occurs. However, the detection and quantification of bacterial virulence factors in complex biological samples are technically demanding challenges. These can be addressed by combining targeted affinity enrichment of antibodies with the sensitivity of liquid chromatography-selected reaction monitoring mass spectrometry (LC-SRM MS). However, many virulence factors have evolved properties that make specific detection by conventional antibodies difficult. We here present an antibody format that is particularly well suited for detection and analysis of immunoglobulin G (IgG)-binding virulence factors. As proof of concept, we have generated single chain fragment variable (scFv) antibodies that specifically target the IgG-binding surface proteins M1 and H of Streptococcus pyogenes. The binding ability of the developed scFv is demonstrated against both recombinant soluble protein M1 and H as well as the intact surface proteins on a wild-type S. pyogenes strain. Additionally, the capacity of the developed scFv antibodies to enrich their target proteins from both simple and complex backgrounds, thereby allowing for detection and quantification with LC-SRM MS, was demonstrated. We have established a workflow that allows for affinity enrichment of bacterial virulence factors.

  12. Study on the Effect of Sunflower Meal Protein Isolate on Extensograph Properties of Black Rice Bread Dough%葵花粕分离蛋白对黑米面包面团拉伸特性的影响

    Institute of Scientific and Technical Information of China (English)

    李云玲; 孙世锴; 朱效兵; 石晶红

    2016-01-01

    以面包专用粉为对照,研究黑米粉、谷朊粉及葵花粕分离蛋白与面包专用粉不同配比混粉面团的拉伸特性,并对各混粉面团的理化指标与拉伸参数进行相关性分析,结果表明,当添加黑米粉的添加量为30%时,添加2%~4%的谷朊粉,1%~3%的葵花粕分离蛋白,能明显改善混粉面团的拉伸特性。%Taking the bread special flour as the contrast,the extensograph properties were studied on bread spe-cial flour dough mixed with different ratio of black rice flour, gluten flour and sunflower meal protein isolate, the correlation analysis of the physical and chemical indexes and extensograph parameters of the mixed flour was carried out, and the results showed that the addition of black rice flour was 30%, added 2%-4%of gluten powder and 1%-3%of sunflower meal protein isolate, could significantly improve the extensograph properties of mixed flour dough.

  13. Photorhabdus adhesion modification protein (Pam) binds extracellular polysaccharide and alters bacterial attachment

    LENUS (Irish Health Repository)

    Jones, Robert T

    2010-05-12

    Abstract Background Photorhabdus are Gram-negative nematode-symbiotic and insect-pathogenic bacteria. The species Photorhabdus asymbiotica is able to infect humans as well as insects. We investigated the secreted proteome of a clinical isolate of P. asymbiotica at different temperatures in order to identify proteins relevant to the infection of the two different hosts. Results A comparison of the proteins secreted by a clinical isolate of P. asymbiotica at simulated insect (28°C) and human (37°C) temperatures led to the identification of a small and highly abundant protein, designated Pam, that is only secreted at the lower temperature. The pam gene is present in all Photorhabdus strains tested and shows a high level of conservation across the whole genus, suggesting it is both ancestral to the genus and probably important to the biology of the bacterium. The Pam protein shows limited sequence similarity to the 13.6 kDa component of a binary toxin of Bacillus thuringiensis. Nevertheless, injection or feeding of heterologously produced Pam showed no insecticidal activity to either Galleria mellonella or Manduca sexta larvae. In bacterial colonies, Pam is associated with an extracellular polysaccharide (EPS)-like matrix, and modifies the ability of wild-type cells to attach to an artificial surface. Interestingly, Surface Plasmon Resonance (SPR) binding studies revealed that the Pam protein itself has adhesive properties. Although Pam is produced throughout insect infection, genetic knockout does not affect either insect virulence or the ability of P. luminescens to form a symbiotic association with its host nematode, Heterorhabditis bacteriophora. Conclusions We studied a highly abundant protein, Pam, which is secreted in a temperature-dependent manner in P. asymbiotica. Our findings indicate that Pam plays an important role in enhancing surface attachment in insect blood. Its association with exopolysaccharide suggests it may exert its effect through mediation of

  14. Photorhabdus adhesion modification protein (Pam binds extracellular polysaccharide and alters bacterial attachment

    Directory of Open Access Journals (Sweden)

    Joyce Susan A

    2010-05-01

    Full Text Available Abstract Background Photorhabdus are Gram-negative nematode-symbiotic and insect-pathogenic bacteria. The species Photorhabdus asymbiotica is able to infect humans as well as insects. We investigated the secreted proteome of a clinical isolate of P. asymbiotica at different temperatures in order to identify proteins relevant to the infection of the two different hosts. Results A comparison of the proteins secreted by a clinical isolate of P. asymbiotica at simulated insect (28°C and human (37°C temperatures led to the identification of a small and highly abundant protein, designated Pam, that is only secreted at the lower temperature. The pam gene is present in all Photorhabdus strains tested and shows a high level of conservation across the whole genus, suggesting it is both ancestral to the genus and probably important to the biology of the bacterium. The Pam protein shows limited sequence similarity to the 13.6 kDa component of a binary toxin of Bacillus thuringiensis. Nevertheless, injection or feeding of heterologously produced Pam showed no insecticidal activity to either Galleria mellonella or Manduca sexta larvae. In bacterial colonies, Pam is associated with an extracellular polysaccharide (EPS-like matrix, and modifies the ability of wild-type cells to attach to an artificial surface. Interestingly, Surface Plasmon Resonance (SPR binding studies revealed that the Pam protein itself has adhesive properties. Although Pam is produced throughout insect infection, genetic knockout does not affect either insect virulence or the ability of P. luminescens to form a symbiotic association with its host nematode, Heterorhabditis bacteriophora. Conclusions We studied a highly abundant protein, Pam, which is secreted in a temperature-dependent manner in P. asymbiotica. Our findings indicate that Pam plays an important role in enhancing surface attachment in insect blood. Its association with exopolysaccharide suggests it may exert its effect

  15. Growth Performance of Clarias Gariepinus Fed Soaked Moringa Oleifera Leaf Meal

    OpenAIRE

    2016-01-01

    The present study evaluates the nutritional potential of soaked-dried Moringa oleifera leaf meal in the diet of Clarias gariepinus. Four isonitrogenous (35% crude protein) diets were formulated with Moringa leaf replacing soybean meal at 0%, 10%, 20% and 30%. Result obtained revealed declined in weight gain, specific growth rate, feed conversion efficiency, protein efficiency ratio and apparent net protein utilization as dietary replacement of Moringa leaf meal increased beyond 10%. It is con...

  16. Effects of partially replacing dietary soybean meal or cottonseed meal with completely hydrolyzed feather meal (defatted rice bran as the carrier) on production, cytokines, adhesive gut bacteria, and disease resistance in hybrid tilapia (Oreochromis niloticus ♀ × Oreochromis aureus ♂).

    Science.gov (United States)

    Zhang, Zhen; Xu, Li; Liu, Wenshu; Yang, Yalin; Du, Zhenyu; Zhou, Zhigang

    2014-12-01

    We formulated experimental diets for hybrid tilapia to investigate the effects of replacing dietary soybean meal (SBM) or cottonseed meal (CSM) by completely hydrolyzed feather meal (defatted rice bran as the carrier; abbreviated as CHFM), with emphasis on fish growth, the composition of adhesive gut bacteria, intestinal and hepatic immune responses, and disease resistance. A series of four isonitrogenous (33% crude protein) and isolipidic (6% crude lipid) diets were formulated to replace the isonitrogenous percentages of CSM or SBM by 6% or 12% CHFM. Quadruplicate groups of healthy and uniformly sized hybrid tilapia were assigned to each experimental diet. Fish were hand fed three times a day for 8 weeks at a rearing temperature of 25-28 °C. The growth performance of hybrid tilapia fed diets with partial replacement of dietary SBM or CSM with CHFM was comparable to the group of fish fed the control diet. The CHFM-containing diets affected the intestinal autochthonous bacterial community in similar ways. All CHFM-containing diets stimulated the expression of heat shock protein 70 in the intestine but suppressed its expression in the liver. Only the CHFM6/SBM diet stimulated the expression of interleukin-1β in intestine, and no effects were observed in all diets to the expression of interleukin-1β in liver. Thus, regarding the immune response in the intestine and liver, CHFM is a good alternative protein source that induces less stress in the host. CHFM did not affect disease resistance to Aeromonas hydrophila infection in hybrid tilapia. These data suggest that CHFM is a good alternative to partially replace SBM and CSM in tilapia feed.

  17. Receptor interacting protein kinase-2 inhibition by CYLD impairs anti-bacterial immune responses in macrophages

    Directory of Open Access Journals (Sweden)

    Katharina eWex

    2016-01-01

    Full Text Available Upon infection with intracellular bacteria, nucleotide oligomerization domain protein 2 (NOD2 recognizes bacterial muramyl dipeptide and binds, subsequently, to receptor-interacting serine/threonine kinase 2 (RIPK2. RIPK2 mediates the activation of immune responses via the nuclear factor-κB (NF-κB and extracellular-signal regulated kinase (ERK pathways. Previously, it has been shown that RIPK2 activation dependens on its K63-ubiquitination by the E3 ligases pellino-3 and ITCH, whereas the deubiquitinating enzyme A20 counter-regulates RIPK2 activity by cleaving K63-polyubiquitin chains from RIPK2. Here, we newly identify the deubiquitinating enzyme CYLD as a new interacting partner and inhibitor of RIPK2. We show that CYLD binds to and removes K63-polyubiquitin chains from RIPK2 in Listeria monocytogenes (Lm infected bone-marrow-derived macrophages (BMDM. CYLD-mediated K63-deubiquitination of RIPK2 resulted in an impaired activation of both NF-κB and ERK1/2 pathways, reduced production of proinflammatory cytokines (IL-6, IL-12, anti-listerial ROS and NO, and, finally, impaired pathogen control. In turn, RIPK2 inhibition by siRNA prevented activation of NF-κB and ERK1/2 and completely abolished the protective effect of CYLD-deficiency with respect to the production of IL-6, NO, ROS and pathogen control. Noteworthy, CYLD also inhibited autophagy of Listeria in a RIPK2-ERK1/2 dependent manner.The protective function of CYLD-deficiency was dependent on IFN-γ pre-stimulation of infected macrophages. Interestingly, the reduced NF-κB activation in CYLD-expressing macrophages limited the protective effect of IFN-γ by reducing NF-κB-dependent STAT1 activation. Taken together, our study identifies CYLD as an important inhibitor of RIPK2-dependent anti-bacterial immune responses in macrophages.

  18. 黑豆饼粕蛋白的超声波提取及其性质的研究%Studies on the Ultrasonic Extraction and the Functional Properties of Black Bean Meal Protein

    Institute of Scientific and Technical Information of China (English)

    张艳; 朱珠; 张传智; 徐淼

    2014-01-01

    以黑豆饼粕为原料,利用超声波辅助法提取黑豆蛋白。最佳工艺参数为:料液比1∶14(g/mL),碱液pH8.5,经过40 min,600 W超声波处理,在pH为4.0盐酸溶液沉降分离,提取率可达58.1%。同时,把所提取的黑豆蛋白与大豆蛋白进行对比分析,其溶解性、乳化性、持水性、持油性都高于大豆蛋白,所以黑豆蛋白可以有更多的应用价值。%To study on the ultrasonic extraction of protein in black bean meal. The result showed the optimum processing parameters are:material liquid ratio 1∶14 (g/mL), pH of alkaline liquid 8.5, ultrasonic time 40 min utes , ultrasonic power 600 W, pH of separation acid solution 4.0. By the above conditions, the extraction rate can reach 58.1%. In addition, to analysis and compare the functional properties of the black bean protein with of soybean protein. The result showed that the black bean meal protein was betters than the soybean protein in solubility, emulsification, features of hold water and hold oil.

  19. Host and bacterial proteins that repress recruitment of LC3 to Shigella early during infection.

    Directory of Open Access Journals (Sweden)

    Leigh A Baxt

    Full Text Available Shigella spp. are intracytosolic gram-negative pathogens that cause disease by invasion and spread through the colonic mucosa, utilizing host cytoskeletal components to form propulsive actin tails. We have previously identified the host factor Toca-1 as being recruited to intracellular S. flexneri and being required for efficient bacterial actin tail formation. We show that at early times during infection (40 min., the type three-secreted effector protein IcsB recruits Toca-1 to intracellular bacteria and that recruitment of Toca-1 is associated with repression of recruitment of LC3, as well as with repression of recruitment of the autophagy marker NDP52, around these intracellular bacteria. LC3 is best characterized as a marker of autophagosomes, but also marks phagosomal membranes in the process LC3-associated phagocytosis. IcsB has previously been demonstrated to be required for S. flexneri evasion of autophagy at late times during infection (4-6 hr by inhibiting binding of the autophagy protein Atg5 to the Shigella surface protein IcsA (VirG. Our results suggest that IcsB and Toca-1 modulation of LC3 recruitment restricts LC3-associated phagocytosis and/or LC3 recruitment to vacuolar membrane remnants. Together with published results, our findings suggest that IcsB inhibits innate immune responses in two distinct ways, first, by inhibiting LC3-associated phagocytosis and/or LC3 recruitment to vacuolar membrane remnants early during infection, and second, by inhibiting autophagy late during infection.

  20. Sequence context of indel mutations and their effect on protein evolution in a bacterial endosymbiont.

    Science.gov (United States)

    Williams, Laura E; Wernegreen, Jennifer J

    2013-01-01

    Indel mutations play key roles in genome and protein evolution, yet we lack a comprehensive understanding of how indels impact evolutionary processes. Genome-wide analyses enabled by next-generation sequencing can clarify the context and effect of indels, thereby integrating a more detailed consideration of indels with our knowledge of nucleotide substitutions. To this end, we sequenced Blochmannia chromaiodes, an obligate bacterial endosymbiont of carpenter ants, and compared it with the close relative, B. pennsylvanicus. The genetic distance between these species is small enough for accurate whole genome alignment but large enough to provide a meaningful spectrum of indel mutations. We found that indels are subjected to purifying selection in coding regions and even intergenic regions, which show a reduced rate of indel base pairs per kilobase compared with nonfunctional pseudogenes. Indels occur almost exclusively in repeat regions composed of homopolymers and multimeric simple sequence repeats, demonstrating the importance of sequence context for indel mutations. Despite purifying selection, some indels occur in protein-coding genes. Most are multiples of three, indicating selective pressure to maintain the reading frame. The deleterious effect of frameshift-inducing indels is minimized by either compensation from a nearby indel to restore reading frame or the indel's location near the 3'-end of the gene. We observed amino acid divergence exceeding nucleotide divergence in regions affected by frameshift-inducing indels, suggesting that these indels may either drive adaptive protein evolution or initiate gene degradation. Our results shed light on how indel mutations impact processes of molecular evolution underlying endosymbiont genome evolution.

  1. Carob pod (Ceratonia siliqua) meal in geese diets.

    Science.gov (United States)

    Sahle, M; Coleou, J; Haas, C

    1992-07-01

    1. The apparent and true metabolisable energy values of carob pods meal for geese were measured to be 6.1 MJ/kg and 6.6 MJ/kg respectively. 2. Performance from 5 to 12 weeks was examined in geese fed on four diets containing 0, 100, 200 and 300 g/kg of carob pods meal. 3. The inclusion of carob pods meal up to 200 g/kg in geese diets did not affect the performance. 4. At 300 g/kg performance was highly depressed. 5. The digestibility of protein in the diets decreased linearly with an increase in the level of inclusion of carob pods meal. 6. The length of small intestine, large intestine and caeca and the weight of gizzard expressed per kg of body weight increased with an increase in the level of carob pods meal, which is rich in fibre, in the diets.

  2. Thermal properties of defatted meal, concentrate, and protein isolate of baru nuts (Dipteryx alata Vog. Propriedades térmicas de farinha desengordurada, concentrado e isolado proteico de baru (Dipteryx alata Vog.

    Directory of Open Access Journals (Sweden)

    Rita de Cássia Avellaneda Guimarães

    2012-03-01

    Full Text Available Baru (Dipteryx alata Vog., a species of legume found in the Brazilian savannas, was investigated in this study for the composition of its flesh and seed. Thermal analyses, Thermogravimetry (TG, and Differential Scanning Calorimetry (DSC were used to investigate the proteins in defatted meal, concentrate, and protein isolate. The protein concentrate was extracted at pH 10, followed by a precipitation at the isoelectric point to obtain the isolate that was spray dried. The thermogravimetric curves were obtained under a nitrogen atmosphere with a 100 mL/minutes flow. The initial, final and peak temperatures and mass loss were analyzed. Within the performed temperature ranges studied, the defatted meal and concentrate presented four steps of mass loss, while the isolate showed only two steps. The protein content of defatted meal from Baru nuts was higher than that of the isolate. On the other hand, there was a reduction in enthalpy, which suggests that the process applied to obtain the baru concentrate and isolate led to protein denaturation.Componentes de polpa e de semente de baru (Dipteryx alata Vog., leguminosa do cerrado brasileiro, foram objetos de estudo neste trabalho. Análises térmicas, Termogravimetria (TG e Calorimetria Exploratória Diferencial (DSC foram utilizadas na investigação de proteínas em farinha desengordurada, concentrado e isolado proteico. A extração do concentrado proteico foi em pH 10, seguida de precipitação no ponto isoelétrico para obter o isolado, o qual foi seco por atomização. As curvas termogravimétricas foram obtidas em atmosfera de nitrogênio em vazão de 100 mL/minutos. As temperaturas iniciais, finais e de pico foram analisadas, assim como a perda de massa. Na faixa de temperatura avaliada, a farinha desengordurada e o concentrado apresentaram quatro etapas de perda de massa, enquanto que o isolado apenas duas etapas. O conteúdo de proteína da farinha desengordurada da semente de Baru foi mais

  3. The use of C-reactive protein in predicting bacterial co-Infection in children with bronchiolitis

    Directory of Open Access Journals (Sweden)

    Mohamad Fares

    2011-03-01

    Full Text Available Background: Bronchiolitis is a potentially life-threatening respiratory illness commonly affecting children who are less than two years of age. Patients with viral lower respiratory tract infection are at risk for co-bacterial infection. Aim: The aim of our study was to evaluate the use of C-reactive protein (CRP in predicting bacterial co-infection in patients hospitalized for bronchiolitis and to correlate the results with the use of antibiotics. Patients and Methods: This is a prospective study that included patients diagnosed with bronchiolitis admitted to Makassed General Hospital in Beirut from October 2008 to April 2009. A tracheal aspirate culture was taken from all patients with bronchiolitis on admission to the hospital. Blood was drawn to test C-reactive protein level, white cell count, transaminases level, and blood sugar level. Results: Forty-nine patients were enrolled in the study and were divided into two groups. Group 1 included patients with positive tracheal aspirate culture and Group 2 included those with negative culture. All patients with a CRP level ≥2 mg/dL have had bacterial co-infection. White cell count, transaminases and blood sugar levels were not predictive for bacterial co-infection. The presence of bacterial co-infection increased the length of hospital stay in the first group by 2 days compared to those in the second group. Conclusion: Bacterial co-infection is frequent in infants with moderate to severe bronchiolitis and requires admission. Our data showed that a CRP level greater than 1.1 mg/dL raised suspicion for bacterial co-infection. Thus, a tracheal aspirate should be investigated microbiologically in all hospitalized patients in order to avoid unnecessary antimicrobial therapy and to shorten the duration of the hospital stay.

  4. Extraction, characterization of components, and potential thermoplastic applications of camelina meal grafted with vinyl monomers.

    Science.gov (United States)

    Reddy, Narendra; Jin, Enqi; Chen, Lihong; Jiang, Xue; Yang, Yiqi

    2012-05-16

    Camelina meal contains oil, proteins, and carbohydrates that can be used to develop value-added bioproducts. In addition to containing valuable polymers, coproducts generated during the production of biofuels are inexpensive and renewable. Camelina is a preferred oilseed crop for biodiesel production because camelina is easier to grow and provides better yields. In this research, the components in camelina meal were extracted and studied for their composition, structure, and properties. The potential of using the camelina meal to develop thermoplastics was also studied by grafting various vinyl monomers. Oil (19%) extracted from camelina meal could be useful for food and fuel applications, and proteins and cellulose in camelina meal could be useful in the development of films, fibers, and thermoplastics. Thermoplastic films developed from grafted camelina meal had excellent wet tensile properties, unlike thermoplastics developed from other biopolymers. Camelina meal grafted with butylmethacrylate (BMA) had high dry and wet tensile strengths of 53.7 and 17.3 MPa, respectively.

  5. Pigments and proteins in green bacterial chlorosomes studied by matrix-assisted laser desorption ionization mass spectrometry

    DEFF Research Database (Denmark)

    Persson, S; Sönksen, C P; Frigaard, N-U

    2000-01-01

    We have used matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS) for mass determination of pigments and proteins in chlorosomes, the light-harvesting organelles from the photosynthetic green sulfur bacterium Chlorobium tepidum. By applying a small volume (1...... homologs in a small amount of green bacterial cells. In addition to information on pigments, the MALDI spectra also contained peaks from chlorosome proteins. Thus we have been able with high precision to confirm the molecular masses of the chlorosome proteins CsmA and CsmE which have been previously...

  6. Bacterial effector binding to ribosomal protein s3 subverts NF-kappaB function.

    Directory of Open Access Journals (Sweden)

    Xiaofei Gao

    2009-12-01

    Full Text Available Enteric bacterial pathogens cause food borne disease, which constitutes an enormous economic and health burden. Enterohemorrhagic Escherichia coli (EHEC causes a severe bloody diarrhea following transmission to humans through various means, including contaminated beef and vegetable products, water, or through contact with animals. EHEC also causes a potentially fatal kidney disease (hemolytic uremic syndrome for which there is no effective treatment or prophylaxis. EHEC and other enteric pathogens (e.g., enteropathogenic E. coli (EPEC, Salmonella, Shigella, Yersinia utilize a type III secretion system (T3SS to inject virulence proteins (effectors into host cells. While it is known that T3SS effectors subvert host cell function to promote diarrheal disease and bacterial transmission, in many cases, the mechanisms by which these effectors bind to host proteins and disrupt the normal function of intestinal epithelial cells have not been completely characterized. In this study, we present evidence that the E. coli O157:H7 nleH1 and nleH2 genes encode T3SS effectors that bind to the human ribosomal protein S3 (RPS3, a subunit of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kappaB transcriptional complexes. NleH1 and NleH2 co-localized with RPS3 in the cytoplasm, but not in cell nuclei. The N-terminal region of both NleH1 and NleH2 was required for binding to the N-terminus of RPS3. NleH1 and NleH2 are autophosphorylated Ser/Thr protein kinases, but their binding to RPS3 is independent of kinase activity. NleH1, but not NleH2, reduced the nuclear abundance of RPS3 without altering the p50 or p65 NF-kappaB subunits or affecting the phosphorylation state or abundance of the inhibitory NF-kappaB chaperone IkappaBalpha NleH1 repressed the transcription of a RPS3/NF-kappaB-dependent reporter plasmid, but did not inhibit the transcription of RPS3-independent reporters. In contrast, NleH2 stimulated RPS3-dependent transcription, as well

  7. Estimating the bending modulus of a FtsZ bacterial-division protein filament

    Science.gov (United States)

    Cytrynbaum, Eric N.; Li, Yongnan Devin; Allard, Jun F.; Mehrabian, Hadi

    2012-01-01

    FtsZ, a cytoskeletal protein homologous to tubulin, is the principle constituent of the division ring in bacterial cells. It is known to have force-generating capacity in vitro and has been conjectured to be the source of the constriction force in vivo. Several models have been proposed to explain the generation of force by the Z ring. Here we re-examine data from in vitro experiments in which Z rings formed and constricted inside tubular liposomes, and we carry out image analysis on previously published data with which to better estimate important model parameters that have proven difficult to measure by direct means. We introduce a membrane-energy-based model for the dynamics of multiple Z rings moving and colliding inside a tubular liposome and a fluid model for the drag of a Z ring as it moves through the tube. Using this model, we estimate an effective membrane bending modulus of 500-700 pNnm. If we assume that FtsZ force generation is driven by hydrolysis into a highly curved conformation, we estimate the FtsZ filament bending modulus to be 310-390 pNnm2. If we assume instead that force is generated by the non-hydrolysis-dependent intermediate curvature conformation, we find that Bf>1400pNnm2. The former value sits at the lower end of the range of previously estimated values and, if correct, may raise challenges for models that rely on filament bending to generate force.

  8. Structural insights into alginate binding by bacterial cell-surface protein.

    Science.gov (United States)

    Temtrirath, Kanate; Murata, Kousaku; Hashimoto, Wataru

    2015-03-02

    A gram-negative Sphingomonas sp. strain A1 inducibly forms a mouth-like pit on the cell surface in the presence of alginate and directly incorporates polymers into the cytoplasm via the pit and ABC transporter. Among the bacterial proteins involved in import of alginate, a cell-surface EfeO-like Algp7 shows an ability to bind alginate, suggesting its contribution to accumulate alginate in the pit. Here, we show identification of its positively charged cluster involved in alginate binding using X-ray crystallography, docking simulation, and site-directed mutagenesis. The tertiary structure of Algp7 was determined at a high resolution (1.99Å) by molecular replacement, although no alginates were included in the structure. Thus, an in silico model of Algp7/oligoalginate was constructed by docking simulation using atomic coordinates of Algp7 and alginate oligosaccharides, where some charged residues were found to be potential candidates for alginate binding. Site-directed mutagenesis was conducted and five purified mutants K68A, K69A, E194A, N221A, and K68A/K69A were subjected to a binding assay. UV absorption difference spectroscopy along with differential scanning fluorimetry analysis indicated that K68A/K69A exhibited a significant reduction in binding affinity with alginate than wild-type Algp7. Based on these data, Lys68/Lys69 residues of Algp7 probably play an important role in binding alginate.

  9. Mass Spectrometric Detection of Bacterial Protein Toxins and Their Enzymatic Activity.

    Science.gov (United States)

    Kalb, Suzanne R; Boyer, Anne E; Barr, John R

    2015-08-31

    Mass spectrometry has recently become a powerful technique for bacterial identification. Mass spectrometry approaches generally rely upon introduction of the bacteria into a matrix-assisted laser-desorption time-of-flight (MALDI-TOF) mass spectrometer with mass spectrometric recognition of proteins specific to that organism that form a reliable fingerprint. With some bacteria, such as Bacillus anthracis and Clostridium botulinum, the health threat posed by these organisms is not the organism itself, but rather the protein toxins produced by the organisms. One such example is botulinum neurotoxin (BoNT), a potent neurotoxin produced by C. botulinum. There are seven known serotypes of BoNT, A-G, and many of the serotypes can be further differentiated into toxin variants, which are up to 99.9% identical in some cases. Mass spectrometric proteomic techniques have been established to differentiate the serotype or toxin variant of BoNT produced by varied strains of C. botulinum. Detection of potent biological toxins requires high analytical sensitivity and mass spectrometry based methods have been developed to determine the enzymatic activity of BoNT and the anthrax lethal toxins produced by B. anthracis. This enzymatic activity, unique for each toxin, is assessed with detection of the toxin-induced cleavage of strategically designed peptide substrates by MALDI-TOF mass spectrometry offering unparalleled specificity. Furthermore, activity assays allow for the assessment of the biological activity of a toxin and its potential health risk. Such methods have become important diagnostics for botulism and anthrax. Here, we review mass spectrometry based methods for the enzymatic activity of BoNT and the anthrax lethal factor toxin.

  10. Genetic evidence for inhibition of bacterial division protein FtsZ by berberine.

    Directory of Open Access Journals (Sweden)

    Jaroslaw M Boberek

    Full Text Available BACKGROUND: Berberine is a plant alkaloid that is widely used as an anti-infective in traditional medicine. Escherichia coli exposed to berberine form filaments, suggesting an antibacterial mechanism that involves inhibition of cell division. Berberine is a DNA ligand and may induce filamentation through induction of the SOS response. Also, there is biochemical evidence for berberine inhibition of the cell division protein FtsZ. Here we aimed to assess possible berberine mechanism(s of action in growing bacteria using genetics tools. METHODOLOGY/PRINCIPAL FINDINGS: First, we tested whether berberine inhibits bacterial growth through DNA damage and induction of the SOS response. The SOS response induced by berberine was much lower compared to that induced by mitomycin C in an SOS response reporter strain. Also, cell filamentation was observed in an SOS-negative E. coli strain. To test whether berberine inhibits FtsZ, we assessed its effects on formation of the cell division Z-rings, and observed a dramatic reduction in Z-rings in the presence of berberine. We next used two different strategies for RNA silencing of ftsZ and both resulted in sensitisation of bacteria to berberine, visible as a drop in the Minimum Inhibitory Concentration (MIC. Furthermore, Fractional Inhibitory Concentration Indices (FICIs showed a high level of synergy between ftsZ silencing and berberine treatment (FICI values of 0.23 and 0.25 for peptide nucleic acid- and expressed antisense RNA-based silencing of ftsZ, respectively. Finally, over-expression of ftsZ led to a mild rescue effect in berberine-treated cells. CONCLUSIONS: The results argue against DNA binding as the primary mechanism of action of berberine and support the hypothesis that its antibacterial properties are due to inhibition of the cell division protein FtsZ. In addition, the genetic approach used here provides a means to rapidly test the activity of other putative FtsZ inhibitors.

  11. Study of total dry matter and protein extraction from canola meal as affected by the pH, salt addition and use of zeta-potential/turbidimetry analysis to optimize the extraction conditions.

    Science.gov (United States)

    Gerzhova, Alina; Mondor, Martin; Benali, Marzouk; Aider, Mohammed

    2016-06-15

    Total dry matter and proteins were differentially and preferentially extracted from canola meal (CM) under different conditions. The effect of the extraction medium pH, CM concentration and salt concentrations were found to have different influences on the extractability of total dry matter and proteins from CM. The pH of the extracting medium had the most significant effect. The maximal total dry matter (42.8±1.18%) extractability was obtained with 5% CM at pH 12 without salt addition, whereas the maximal for total protein (58.12±1.47%) was obtained with 15% CM under the same conditions. The minimal extractability for the dry matter (26.63±0.67%) was obtained with 5% CM at pH 10 without salt added and the minimal protein extractability was observed in a 10% CM at pH 10, in 0.01 NaCl. Turbidity and ζ-potential measurements indicated that pH 5 was the optimum condition for the highest protein extraction yield. SDS-PAGE analysis showed that salt addition contributes to higher solubility of canola proteins specifically cruciferin fraction, although it reduces napin extraction.

  12. Bacterial Surface-Displayed GII.4 Human Norovirus Capsid Proteins Bound to HBGA-Like Molecules in Romaine Lettuce.

    Science.gov (United States)

    Wang, Ming; Rong, Shaofeng; Tian, Peng; Zhou, Yue; Guan, Shimin; Li, Qianqian; Wang, Dapeng

    2017-01-01

    Human Noroviruses (HuNoVs) are the main cause of non-bacterial gastroenteritis. Contaminated produce is a main vehicle for dissemination of HuNoVs. In this study, we used an ice nucleation protein mediated surface display system to present the protruding domain of GII.4 HuNoV capsid protein on bacterial surface and used it as a new strategy to explore interaction between HuNoV protein and receptor candidates from romaine lettuce. The surface-displayed HuNoV proteins were confirmed on the surface of the transformed bacteria by an immunofluorescence assay. The distribution patterns of the surface-displayed HuNoV proteins in romaine lettuce were identified through a confocal immunofluorescence assay. The surface-displayed HuNoV proteins could be found in the stomata, and the surfaces of vein and leaf of romaine lettuce. The surface-displayed HuNoV proteins could be captured by an ELISA assay utilizing extract from leaf (LE) or vein (VE). The binding of the surface-displayed HuNoV proteins to LE or VE could be competitively blocked by histo-blood group antigens from human saliva. In addition, the binding of the surface-displayed HuNoV proteins to LE or VE could also be attenuated by heat denaturation of lettuce proteins, and abolished by oxidation of lettuce carbohydrates. The results indicated that histo-blood group antigen-like molecules in LE or VE were involved in the binding of the surface-displayed HuNoV proteins to romaine lettuce. All data demonstrated that the surface-displayed HuNoV proteins could be utilized in a new and simple system for investigation of the interaction between the HuNoVs and their candidate ligands.

  13. Interferon-alpha in viral and bacterial gastroenteritis: a comparison with C-reactive protein and interleukin-6.

    Science.gov (United States)

    Mangiarotti, P; Moulin, F; Palmer, P; Ravilly, S; Raymond, J; Gendrel, D

    1999-06-01

    The aim of the study was to identify serum markers able to differentiate bacterial and viral origin in acute diarrhoea. Interferon-alpha (INF-alpha), C-reactive protein (CRP) and interleukin-6 were determined on admission in the sera of 119 children aged between 1 mo and 14 y who were hospitalized for rotavirus (n = 60) or bacterial diarrhoea (Salmonella spp. 39 cases, Shigella spp. 15 cases, Campylobacter jejuni 5 cases). CRP concentration was >10 mg/l in 48.3% of children with viral gastroenteritis and 86.4% of children with bacterial gastroenteritis. IL6 concentration was >100 pg/ml in 11.7% and 26.3% of cases, respectively. INF-alpha was detected in 79.1% of children with rotavirus (sens 79%) and in 3.5% (spec 93%) with bacterial gastroenteritis. However the INF-alpha assay takes 48 h and pathogens are often identified from stools before interferon results are available. We found that serum markers are not discriminating enough to differentiate between viral and bacterial gastroenteritis in emergency cases.

  14. Structure of the complex between teicoplanin and a bacterial cell-wall peptide: use of a carrier-protein approach

    Energy Technology Data Exchange (ETDEWEB)

    Economou, Nicoleta J.; Zentner, Isaac J. [Drexel University College of Medicine, 245 North 15th Street, Philadelphia, PA 19102 (United States); Lazo, Edwin; Jakoncic, Jean; Stojanoff, Vivian [Brookhaven National Laboratory, Upton, NY 11973 (United States); Weeks, Stephen D.; Grasty, Kimberly C.; Cocklin, Simon; Loll, Patrick J. [Drexel University College of Medicine, 245 North 15th Street, Philadelphia, PA 19102 (United States)

    2013-04-01

    Using a carrier-protein strategy, the structure of teicoplanin bound to its bacterial cell-wall target has been determined. The structure reveals the molecular determinants of target recognition, flexibility in the antibiotic backbone and intrinsic radiation sensitivity of teicoplanin. Multidrug-resistant bacterial infections are commonly treated with glycopeptide antibiotics such as teicoplanin. This drug inhibits bacterial cell-wall biosynthesis by binding and sequestering a cell-wall precursor: a d-alanine-containing peptide. A carrier-protein strategy was used to crystallize the complex of teicoplanin and its target peptide by fusing the cell-wall peptide to either MBP or ubiquitin via native chemical ligation and subsequently crystallizing the protein–peptide–antibiotic complex. The 2.05 Å resolution MBP–peptide–teicoplanin structure shows that teicoplanin recognizes its ligand through a combination of five hydrogen bonds and multiple van der Waals interactions. Comparison of this teicoplanin structure with that of unliganded teicoplanin reveals a flexibility in the antibiotic peptide backbone that has significant implications for ligand recognition. Diffraction experiments revealed an X-ray-induced dechlorination of the sixth amino acid of the antibiotic; it is shown that teicoplanin is significantly more radiation-sensitive than other similar antibiotics and that ligand binding increases radiosensitivity. Insights derived from this new teicoplanin structure may contribute to the development of next-generation antibacterials designed to overcome bacterial resistance.

  15. Appetite regulation via exercise prior or subsequent to high-fat meal consumption.

    Science.gov (United States)

    Cheng, Mary Huey-Yu; Bushnell, Darcy; Cannon, Daniel T; Kern, Mark

    2009-02-01

    This study assessed the effect of exercise timing relative to meal consumption on appetite and its hormonal regulators (i.e., PYY(3-36), ghrelin and leptin) in moderately active young men. Twelve men performed three trials in a random order: (1) meal consumption, (2) exercise 2h after a meal, (3) exercise 1h before a meal. The test meal provided 16.5 kcal kg(-1) with 70% fat, 26% carbohydrate and 4% protein. Exercise was performed at a work rate eliciting 60% of VO(2max) for 50 min. Hunger ratings and plasma leptin concentrations were measured at baseline and hours 1, 3, 5, and 7 post-meal, and plasma concentrations of ghrelin and PYY(3-36) were measured at baseline and 1, 3, and 7h after meal consumption. Exercise performed 2h after meal consumption extended the appetite suppressing effect of food intake. Furthermore, plasma PYY(3-36) concentration tended to be elevated by exercise after meal consumption. Exercise prior to food intake decreased appetite and increased plasma ghrelin concentrations. No response to timing of exercise relative to food intake on plasma leptin concentration was detected. These data indicated the timing of exercise to meal consumption may influence appetite and its hormonal regulators. Post-meal exercise may extend the suppressive effects of meal consumption on appetite.

  16. The effects of McDonalds, Kentucky Fried Chicken and Pizza Hut meals on recommended diets.

    Science.gov (United States)

    Malouf, N M; Colagiuri, S

    1995-06-01

    The objective was to study the effect of three common takeaway meals on recommended healthy diets. New South Wales Department of Health recommended diets of 5020, 6275, 9205 and 12,540 kilojoules were used. An evening meal from each of these diets was substituted with one of three common fast food chain takeaway meals 1, 2, 3 and 5 times per week. The 3 takeaway meals were from McDonalds, Pizza Hut and Kentucky Fried Chicken. The effects of each of these meals on average daily kilojoule, fibre, fat, P/S ratio, protein and carbohydrate intakes were assessed. The takeaway meals were high in fat and kilojoules and low in fibre and therefore contravened the Dietary Guidelines for Australians. Addition of these meals increased average kilojoule consumption and the percentage energy contribution of fat and decreased the P/S ratio and fibre intake. The magnitude of these deleterious effects was directly proportional to the number of times the meals were included each week and inversely proportional to the energy content of the diet. The adverse effects were greatest with the McDonalds and Kentucky Fried Chicken meals. Takeaway meals may be convenient but the meals which were tested were too high in fat and kilojoules and too low in fibre to be a regular part of a balanced diet. Even one takeaway meal per week adversely affects the lower kilojoule recommended healthy diets.

  17. Substitution of soybean meal for cottonseed meal in multiple supplements for grazing beef heifers in the dry season

    Directory of Open Access Journals (Sweden)

    Román Maza Ortega

    2016-02-01

    Full Text Available The objective of this study was to evaluate the effect of substituting soybean meal for cottonseed meal in multiple supplements on the nutritional characteristics and performance of beef heifers in their postweaning phase on Brachiaria decumbens pastures during the dry season. Twenty-four Nellore beef heifers (average initial age and weight of 8 mo and 210±6 kg, respectively were used. The design was completely randomized, with four treatments and six replicates. Supplements contained approximately 30% crude protein (CP and a progressive substitution of soybean meal for cottonseed meal (0, 50 and 100%. The control animals received only a mineral mixture ad libitum, and those on the other treatments received supplementation at 1.0 kg/animal/day. No differences were found in ADG between supplemented and control animals (P>0.10. Supplementation increased crude protein (CP intake only (P<0.10. The level of substitution of soybean meal for cottonseed meal did not affect (P>0.10 the intake of supplemented animals. Supplementation elevated the apparent digestibility coefficients (P<0.10 of OM, CP, NFC and TDN, but not EE or NDFap (P>0.10. A positive linear effect (P<0.10 of the level of substitution of soybean meal for cottonseed cake was observed on the digestibility of OM, NFC and TDN. Supplementation and the level of substitution had an effect (P<0.10 on the serum urea nitrogen and urine urea nitrogen contents. Supplementation or substitution level had no effect on the flow of microbial nitrogen to the intestine (MICN or efficiency of microbial protein synthesis (EMPS (P>0.10. Substitution caused a decreasing linear effect (P<0.10 on microbial nitrogen/nitrogen intake ratio (MICNR. In conclusion, substitution of soybean meal for cottonseed meal in multiple supplements during the dry season does not impair the productive performance of beef heifers.

  18. Ras GTPase-like protein MglA, a controller of bacterial social-motility in Myxobacteria, has evolved to control bacterial predation by Bdellovibrio.

    Directory of Open Access Journals (Sweden)

    David S Milner

    2014-04-01

    Full Text Available Bdellovibrio bacteriovorus invade Gram-negative bacteria in a predatory process requiring Type IV pili (T4P at a single invasive pole, and also glide on surfaces to locate prey. Ras-like G-protein MglA, working with MglB and RomR in the deltaproteobacterium Myxococcus xanthus, regulates adventurous gliding and T4P-mediated social motility at both M. xanthus cell poles. Our bioinformatic analyses suggested that the GTPase activating protein (GAP-encoding gene mglB was lost in Bdellovibrio, but critical residues for MglA(Bd GTP-binding are conserved. Deletion of mglA(Bd abolished prey-invasion, but not gliding, and reduced T4P formation. MglA(Bd interacted with a previously uncharacterised tetratricopeptide repeat (TPR domain protein Bd2492, which we show localises at the single invasive pole and is required for predation. Bd2492 and RomR also interacted with cyclic-di-GMP-binding receptor CdgA, required for rapid prey-invasion. Bd2492, RomR(Bd and CdgA localize to the invasive pole and may facilitate MglA-docking. Bd2492 was encoded from an operon encoding a TamAB-like secretion system. The TamA protein and RomR were found, by gene deletion tests, to be essential for viability in both predatory and non-predatory modes. Control proteins, which regulate bipolar T4P-mediated social motility in swarming groups of deltaproteobacteria, have adapted in evolution to regulate the anti-social process of unipolar prey-invasion in the "lone-hunter" Bdellovibrio. Thus GTP-binding proteins and cyclic-di-GMP inputs combine at a regulatory hub, turning on prey-invasion and allowing invasion and killing of bacterial pathogens and consequent predatory growth of Bdellovibrio.

  19. Lactoferrin Decreases the Intestinal Inflammation Triggered by a Soybean Meal-Based Diet in Zebrafish

    Science.gov (United States)

    Ulloa, Pilar E.; Solís, Camila J.; Alaurent, Trevor G. S.; Caruffo, Mario; Hernández, Adrián J.; Feijóo, Carmen G.

    2016-01-01

    Intestinal inflammation is a harmful condition in fish that can be triggered by the ingestion of soybean meal. Due to the positive costs-benefits ratio of including soybean meal in farmed fish diets, identifying additives with intestinal anti-inflammatory effects could contribute to solving the issues caused by this plant protein. This study evaluated the effect of incorporating lactoferrin (LF) into a soybean meal-based diet on intestinal inflammation in zebrafish. Larvae were fed with diets containing 50% soybean meal (50SBM) or 50SBM supplemented with LF to 0.5, 1, 1.5 g/kg (50SBM+LF0.5; 50SBM+LF1.0; 50SBM+LF1.5). The 50SBM+LF1.5 diet was the most efficient and larvae had a reduced number of neutrophils in the intestine compared with 50SBM larvae and an indistinguishable number compared with control larvae. Likewise, the transcription of genes involved in neutrophil migration and intestinal mucosal barrier functions (mmp9, muc2.2, and β-def-1) were increased in 50SBM larvae but were normally expressed in 50SBM+LF1.5 larvae. To determine the influence of intestinal inflammation on the general immune response, larvae were challenged with Edwardsiella tarda. Larvae with intestinal inflammation had increased mortality rate compared to control larvae. Importantly, 50SBM+LF1.5 larvae had a mortality rate lower than control larvae. These results demonstrate that LF displays a dual effect in zebrafish, acting as an intestinal anti-inflammatory agent and improving performance against bacterial infection. PMID:27247950

  20. Lactoferrin Decreases the Intestinal Inflammation Triggered by a Soybean Meal-Based Diet in Zebrafish

    Directory of Open Access Journals (Sweden)

    Pilar E. Ulloa

    2016-01-01

    Full Text Available Intestinal inflammation is a harmful condition in fish that can be triggered by the ingestion of soybean meal. Due to the positive costs-benefits ratio of including soybean meal in farmed fish diets, identifying additives with intestinal anti-inflammatory effects could contribute to solving the issues caused by this plant protein. This study evaluated the effect of incorporating lactoferrin (LF into a soybean meal-based diet on intestinal inflammation in zebrafish. Larvae were fed with diets containing 50% soybean meal (50SBM or 50SBM supplemented with LF to 0.5, 1, 1.5 g/kg (50SBM+LF0.5; 50SBM+LF1.0; 50SBM+LF1.5. The 50SBM+LF1.5 diet was the most efficient and larvae had a reduced number of neutrophils in the intestine compared with 50SBM larvae and an indistinguishable number compared with control larvae. Likewise, the transcription of genes involved in neutrophil migration and intestinal mucosal barrier functions (mmp9, muc2.2, and β-def-1 were increased in 50SBM larvae but were normally expressed in 50SBM+LF1.5 larvae. To determine the influence of intestinal inflammation on the general immune response, larvae were challenged with Edwardsiella tarda. Larvae with intestinal inflammation had increased mortality rate compared to control larvae. Importantly, 50SBM+LF1.5 larvae had a mortality rate lower than control larvae. These results demonstrate that LF displays a dual effect in zebrafish, acting as an intestinal anti-inflammatory agent and improving performance against bacterial infection.

  1. Dielectric properties of wheat flour mixed with oat meal

    Science.gov (United States)

    Łuczycka, D.; Czubaszek, A.; Fujarczuk, M.; Pruski, K.

    2013-03-01

    Possibilities of using electric methods for determining admixtures of oat meal to wheat flour, type 650 are presented. In wheat flour, oat meal and mixtures containing 10, 20 and 30% of the oat meal, moisture, protein, starch and ash content, sedimentation value, yield and softening of wet gluten were determined. In samples containing 0, 5, 10, 15, 20, 25, 30 and 100% of oat meal, the dielectric loss factor and conductivity were determined using an impedance analyzer for electromagnetic field frequency ranging from 0.1-20 kHz. It was found that the dielectric loss factor varied for tested material. The best distinguishing between tested mixtures was obtained at the measuring electromagnetic field frequency of 20 kHz. The loss factor was significantly correlated with the yield of wet gluten and the sedimentation value, parameters indicating the amount and quality of gluten proteins in flour.

  2. An Evolutionary Strategy for All-Atom Folding of the 60-Amino-Acid Bacterial Ribosomal Protein L20

    Science.gov (United States)

    Schug, A.; Wenzel, W.

    2006-01-01

    We have investigated an evolutionary algorithm for de novo all-atom folding of the bacterial ribosomal protein L20. We report results of two simulations that converge to near-native conformations of this 60-amino-acid, four-helix protein. We observe a steady increase of “native content” in both simulated ensembles and a large number of near-native conformations in their final populations. We argue that these structures represent a significant fraction of the low-energy metastable conformations, which characterize the folding funnel of this protein. These data validate our all-atom free-energy force field PFF01 for tertiary structure prediction of a previously inaccessible structural family of proteins. We also compare folding simulations of the evolutionary algorithm with the basin-hopping technique for the Trp-cage protein. We find that the evolutionary algorithm generates a dynamic memory in the simulated population, which leads to faster overall convergence. PMID:16565067

  3. N-terminal fusion tags for effective production of g-protein-coupled receptors in bacterial cell-free systems.

    Science.gov (United States)

    Lyukmanova, E N; Shenkarev, Z O; Khabibullina, N F; Kulbatskiy, D S; Shulepko, M A; Petrovskaya, L E; Arseniev, A S; Dolgikh, D A; Kirpichnikov, M P

    2012-10-01

    G-protein-coupled receptors (GPCR) constitute one of the biggest families of membrane proteins. In spite of the fact that they are highly relevant to pharmacy, they have remained poorly explored. One of the main bottlenecks encountered in structural-functional studies of GPCRs is the difficulty to produce sufficient amounts of the proteins. Cell-free systems based on bacterial extracts fromE. colicells attract much attention as an effective tool for recombinant production of membrane proteins. GPCR production in bacterial cell-free expression systems is often inefficient because of the problems associated with the low efficiency of the translation initiation process. This problem could be resolved if GPCRs were expressed in the form of hybrid proteins with N-terminal polypeptide fusion tags. In the present work, three new N-terminal fusion tags are proposed for cell-free production of the human β2-adrenergic receptor, human M1 muscarinic acetylcholine receptor, and human somatostatin receptor type 5. It is demonstrated that the application of an N-terminal fragment (6 a.a.) of bacteriorhodopsin fromExiguobacterium sibiricum(ESR-tag), N-terminal fragment (16 а.о.) of RNAse A (S-tag), and Mistic protein fromB. subtilisallows to increase the CF synthesis of the target GPCRs by 5-38 times, resulting in yields of 0.6-3.8 mg from 1 ml of the reaction mixture, which is sufficient for structural-functional studies.

  4. Monoclonal antibodies against DNA-binding tips of DNABII proteins disrupt biofilms in vitro and induce bacterial clearance in vivo

    Directory of Open Access Journals (Sweden)

    Laura A. Novotny

    2016-08-01

    Full Text Available The vast majority of chronic and recurrent bacterial diseases are attributed to the presence of a recalcitrant biofilm that contributes significantly to pathogenesis. As such, these diseases will require an innovative therapeutic approach. We targeted DNABII proteins, an integral component of extracellular DNA (eDNA which is universally found as part of the pathogenic biofilm matrix to develop a biofilm disrupting therapeutic. We show that a cocktail of monoclonal antibodies directed against specific epitopes of a DNABII protein is highly effective to disrupt diverse biofilms in vitro as well as resolve experimental infection in vivo, in both a chinchilla and murine model. Combining this monoclonal antibody cocktail with a traditional antibiotic to kill bacteria newly released from the biofilm due to the action of the antibody cocktail was highly effective. Our results strongly support these monoclonal antibodies as attractive candidates for lead optimization as a therapeutic for resolution of bacterial biofilm diseases.

  5. Feature extraction by statistical contact potentials and wavelet transform for predicting subcellular localizations in gram negative bacterial proteins.

    Science.gov (United States)

    Arango-Argoty, G A; Jaramillo-Garzón, J A; Castellanos-Domínguez, G

    2015-01-07

    Predicting the localization of a protein has become a useful practice for inferring its function. Most of the reported methods to predict subcellular localizations in Gram-negative bacterial proteins make use of standard protein representations that generally do not take into account the distribution of the amino acids and the structural information of the proteins. Here, we propose a protein representation based on the structural information contained in the pairwise statistical contact potentials. The wavelet transform decodes the information contained in the primary structure of the proteins, allowing the identification of patterns along the proteins, which are used to characterize the subcellular localizations. Then, a support vector machine classifier is trained to categorize them. Cellular compartments like periplasm and extracellular medium are difficult to predict, having a high false negative rate. The wavelet-based method achieves an overall high performance while maintaining a low false negative rate, particularly, on "periplasm" and "extracellular medium". Our results suggest the proposed protein characterization is a useful alternative to representing and predicting protein sequences over the classical and cutting edge protein depictions.

  6. Diversity and evolution of bacterial twin arginine translocase protein, TatC, reveals a protein secretion system that is evolving to fit its environmental niche.

    Directory of Open Access Journals (Sweden)

    Domenico Simone

    Full Text Available BACKGROUND: The twin-arginine translocation (Tat protein export system enables the transport of fully folded proteins across a membrane. This system is composed of two integral membrane proteins belonging to TatA and TatC protein families and in some systems a third component, TatB, a homolog of TatA. TatC participates in substrate protein recognition through its interaction with a twin arginine leader peptide sequence. METHODOLOGY/PRINCIPAL FINDINGS: The aim of this study was to explore TatC diversity, evolution and sequence conservation in bacteria to identify how TatC is evolving and diversifying in various bacterial phyla. Surveying bacterial genomes revealed that 77% of all species possess one or more tatC loci and half of these classes possessed only tatC and tatA genes. Phylogenetic analysis of diverse TatC homologues showed that they were primarily inherited but identified a small subset of taxonomically unrelated bacteria that exhibited evidence supporting lateral gene transfer within an ecological niche. Examination of bacilli tatCd/tatCy isoform operons identified a number of known and potentially new Tat substrate genes based on their frequent association to tatC loci. Evolutionary analysis of these Bacilli isoforms determined that TatCy was the progenitor of TatCd. A bacterial TatC consensus sequence was determined and highlighted conserved and variable regions within a three dimensional model of the Escherichia coli TatC protein. Comparative analysis between the TatC consensus sequence and Bacilli TatCd/y isoform consensus sequences revealed unique sites that may contribute to isoform substrate specificity or make TatA specific contacts. Synonymous to non-synonymous nucleotide substitution analyses of bacterial tatC homologues determined that tatC sequence variation differs dramatically between various classes and suggests TatC specialization in these species. CONCLUSIONS/SIGNIFICANCE: TatC proteins appear to be diversifying within

  7. Nutrient quality of fast food kids meals

    Science.gov (United States)

    Exposure of children to kids’ meals at fast food restaurants is high; however, the nutrient quality of such meals has not been systematically assessed. We assessed the nutrient quality of fast food meals marketed to young children, i.e., "kids meals". The nutrient quality of kids’ meals was assessed...

  8. Coevolved Mutations Reveal Distinct Architectures for Two Core Proteins in the Bacterial Flagellar Motor.

    Directory of Open Access Journals (Sweden)

    Alessandro Pandini

    Full Text Available Switching of bacterial flagellar rotation is caused by large domain movements of the FliG protein triggered by binding of the signal protein CheY to FliM. FliG and FliM form adjacent multi-subunit arrays within the basal body C-ring. The movements alter the interaction of the FliG C-terminal (FliGC "torque" helix with the stator complexes. Atomic models based on the Salmonella entrovar C-ring electron microscopy reconstruction have implications for switching, but lack consensus on the relative locations of the FliG armadillo (ARM domains (amino-terminal (FliGN, middle (FliGM and FliGC as well as changes during chemotaxis. The generality of the Salmonella model is challenged by the variation in motor morphology and response between species. We studied coevolved residue mutations to determine the unifying elements of switch architecture. Residue interactions, measured by their coevolution, were formalized as a network, guided by structural data. Our measurements reveal a common design with dedicated switch and motor modules. The FliM middle domain (FliMM has extensive connectivity most simply explained by conserved intra and inter-subunit contacts. In contrast, FliG has patchy, complex architecture. Conserved structural motifs form interacting nodes in the coevolution network that wire FliMM to the FliGC C-terminal, four-helix motor module (C3-6. FliG C3-6 coevolution is organized around the torque helix, differently from other ARM domains. The nodes form separated, surface-proximal patches that are targeted by deleterious mutations as in other allosteric systems. The dominant node is formed by the EHPQ motif at the FliMMFliGM contact interface and adjacent helix residues at a central location within FliGM. The node interacts with nodes in the N-terminal FliGc α-helix triad (ARM-C and FliGN. ARM-C, separated from C3-6 by the MFVF motif, has poor intra-network connectivity consistent with its variable orientation revealed by structural data. ARM

  9. pH6 antigen (PsaA protein) of Yersinia pestis, a novel bacterial Fc-receptor.

    Science.gov (United States)

    Zav'yalov, V P; Abramov, V M; Cherepanov, P G; Spirina, G V; Chernovskaya, T V; Vasiliev, A M; Zav'yalova, G A

    1996-05-01

    It was found that recombinant pH6 antigen (rPsaA protein) forming virulence-associated fimbriae on the surface of Yersinia pestis at pH 6.7 in host macrophage phagolysosomes or extracellularly in abscesses such as buboes, is a novel bacterial Fc-receptor. rPsaA protein displays reactivity with human IgG1, IgG2 and IgG3 subclasses but does not react with rabbit, mouse and sheep IgG.

  10. Healthy meals on the menu

    DEFF Research Database (Denmark)

    Thunström, Linda; Nordström, Leif Jonas; Shogren, Jason

    2016-01-01

    Menu labelling of meals prepared away from home is a policy designed to help consumers make healthier food choices. In this paper we use a field experiment in Sweden to examine if a restaurant benefits from introducing a meal labelled as healthy on its menu by experiencing an overall increase...... in sales. We cannot reject the hypothesis that sales are the same before and after the introduction of a meal labelled as healthy on the menu, i.e. our data does not support the idea that restaurants increase their sales from supplying a meal labelled as healthy....

  11. Bacterial beta-lactamase fragmentation complementation strategy can be used as a method for identifying interacting protein pairs.

    Science.gov (United States)

    Park, Jong-Hwa; Back, Jung Ho; Hahm, Soo Hyun; Shim, Hye-Young; Park, Min Ju; Ko, Sung Il; Han, Ye Sun

    2007-10-01

    We investigated the applicability of the TEM-1 beta- lactamase fragment complementation (BFC) system to develop a strategy for the screening of protein-protein interactions in bacteria. A BFC system containing a human Fas-associated death domain (hFADD) and human Fas death domain (hFasDD) was generated. The hFADD-hFasDD interaction was verified by cell survivability in ampicillin-containing medium and the colorimetric change of nitrocefin. It was also confirmed by His pull-down assay using cell lysates obtained in selection steps. A coiled-coil helix coiled-coil domain-containing protein 5 (CHCH5) was identified as an interacting protein of human uracil DNA glycosylase (hUNG) from the bacterial BFC cDNA library strategy. The interaction between hUNG and CHCH5 was further confirmed with immunoprecipitation using a mammalian expression system. CHCH5 enhanced the DNA glycosylase activity of hUNG to remove uracil from DNA duplexes containing a U/G mismatch pair. These results suggest that the bacterial BFC cDNA library strategy can be effectively used to identify interacting protein pairs.

  12. International Society of Sports Nutrition position stand: meal frequency

    Directory of Open Access Journals (Sweden)

    Stout Jeffrey R

    2011-03-01

    Full Text Available Abstract Position Statement: Admittedly, research to date examining the physiological effects of meal frequency in humans is somewhat limited. More specifically, data that has specifically examined the impact of meal frequency on body composition, training adaptations, and performance in physically active individuals and athletes is scant. Until more research is available in the physically active and athletic populations, definitive conclusions cannot be made. However, within the confines of the current scientific literature, we assert that: 1. Increasing meal frequency does not appear to favorably change body composition in sedentary populations. 2. If protein levels are adequate, increasing meal frequency during periods of hypoenergetic dieting may preserve lean body mass in athletic populations. 3. Increased meal frequency appears to have a positive effect on various blood markers of health, particularly LDL cholesterol, total cholesterol, and insulin. 4. Increased meal frequency does not appear to significantly enhance diet induced thermogenesis, total energy expenditure or resting metabolic rate. 5. Increasing meal frequency appears to help decrease hunger and improve appetite control. The following literature review has been prepared by the authors in support of the aforementioned position statement.

  13. Crystal structure of bacterial cell-surface alginate-binding protein with an M75 peptidase motif

    Energy Technology Data Exchange (ETDEWEB)

    Maruyama, Yukie; Ochiai, Akihito [Laboratory of Basic and Applied Molecular Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011 (Japan); Mikami, Bunzo [Laboratory of Applied Structural Biology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011 (Japan); Hashimoto, Wataru [Laboratory of Basic and Applied Molecular Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011 (Japan); Murata, Kousaku, E-mail: kmurata@kais.kyoto-u.ac.jp [Laboratory of Basic and Applied Molecular Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011 (Japan)

    2011-02-18

    Research highlights: {yields} Bacterial alginate-binding Algp7 is similar to component EfeO of Fe{sup 2+} transporter. {yields} We determined the crystal structure of Algp7 with a metal-binding motif. {yields} Algp7 consists of two helical bundles formed through duplication of a single bundle. {yields} A deep cleft involved in alginate binding locates around the metal-binding site. {yields} Algp7 may function as a Fe{sup 2+}-chelated alginate-binding protein. -- Abstract: A gram-negative Sphingomonas sp. A1 directly incorporates alginate polysaccharide into the cytoplasm via the cell-surface pit and ABC transporter. A cell-surface alginate-binding protein, Algp7, functions as a concentrator of the polysaccharide in the pit. Based on the primary structure and genetic organization in the bacterial genome, Algp7 was found to be homologous to an M75 peptidase motif-containing EfeO, a component of a ferrous ion transporter. Despite the presence of an M75 peptidase motif with high similarity, the Algp7 protein purified from recombinant Escherichia coli cells was inert on insulin B chain and N-benzoyl-Phe-Val-Arg-p-nitroanilide, both of which are substrates for a typical M75 peptidase, imelysin, from Pseudomonas aeruginosa. The X-ray crystallographic structure of Algp7 was determined at 2.10 A resolution by single-wavelength anomalous diffraction. Although a metal-binding motif, HxxE, conserved in zinc ion-dependent M75 peptidases is also found in Algp7, the crystal structure of Algp7 contains no metal even at the motif. The protein consists of two structurally similar up-and-down helical bundles as the basic scaffold. A deep cleft between the bundles is sufficiently large to accommodate macromolecules such as alginate polysaccharide. This is the first structural report on a bacterial cell-surface alginate-binding protein with an M75 peptidase motif.

  14. Meal Elements - a Way of optimising ready to eat Meals

    DEFF Research Database (Denmark)

    Engelund, Eva Høy; Friis, Alan; Jacobsen, Peter

    The aim of this project is to develop a concept for improvement of the quality of food produced in large-scale kitchens. Using meal elements in large-scale kitchens in combination with production planning and over-all structuring of activities generally improves the quality of the meal prepared....

  15. Comparative proteome analysis of psychrophilic versus mesophilic bacterial species: Insights into the molecular basis of cold adaptation of proteins

    Directory of Open Access Journals (Sweden)

    Reddy Boojala

    2009-01-01

    Full Text Available Abstract Background Cold adapted or psychrophilic organisms grow at low temperatures, where most of other organisms cannot grow. This adaptation requires a vast array of sequence, structural and physiological adjustments. To understand the molecular basis of cold adaptation of proteins, we analyzed proteomes of psychrophilic and mesophilic bacterial species and compared the differences in amino acid composition and substitution patterns to investigate their likely association with growth temperatures. Results In psychrophilic bacteria, serine, aspartic acid, threonine and alanine are overrepresented in the coil regions of secondary structures, whilst glutamic acid and leucine are underrepresented in the helical regions. Compared to mesophiles, psychrophiles comprise a significantly higher proportion of amino acids that contribute to higher protein flexibility in the coil regions of proteins, such as those with tiny/small or neutral side chains. Amino acids with aliphatic, basic, aromatic and hydrophilic side chains are underrepresented in the helical regions of proteins of psychrophiles. The patterns of amino acid substitutions between the orthologous proteins of psychrophiles versus mesophiles are significantly different for several amino acids when compared to their substitutions in orthologous proteins of within the mesophiles or psychrophiles. Conclusion Current results provide quantitative substitution preferences (or avoidance of amino acids that lead to the adaptation of proteins to cold temperatures. These finding would help future efforts in selecting mutations for rational design of proteins with enhanced psychrophilic properties.

  16. Localization of a bacterial group II intron-encoded protein in eukaryotic nuclear splicing-related cell compartments.

    Directory of Open Access Journals (Sweden)

    Rafael Nisa-Martínez

    Full Text Available Some bacterial group II introns are widely used for genetic engineering in bacteria, because they can be reprogrammed to insert into the desired DNA target sites. There is considerable interest in developing this group II intron gene targeting technology for use in eukaryotes, but nuclear genomes present several obstacles to the use of this approach. The nuclear genomes of eukaryotes do not contain group II introns, but these introns are thought to have been the progenitors of nuclear spliceosomal introns. We investigated the expression and subcellular localization of the bacterial RmInt1 group II intron-encoded protein (IEP in Arabidopsis thaliana protoplasts. Following the expression of translational fusions of the wild-type protein and several mutant variants with EGFP, the full-length IEP was found exclusively in the nucleolus, whereas the maturase domain alone targeted EGFP to nuclear speckles. The distribution of the bacterial RmInt1 IEP in plant cell protoplasts suggests that the compartmentalization of eukaryotic cells into nucleus and cytoplasm does not prevent group II introns from invading the host genome. Furthermore, the trafficking of the IEP between the nucleolus and the speckles upon maturase inactivation is consistent with the hypothesis that the spliceosomal machinery evolved from group II introns.

  17. Amino acid digestibility and concentration of digestible and metabolizable energy in soybean meal produced from conventional, high-protein, or low-oligosaccharide varieties of soybeans and fed to growing pigs.

    Science.gov (United States)

    Baker, K M; Stein, H H

    2009-07-01

    Two experiments were conducted to determine AA digestibility and the concentration of DE and ME in 5 sources of soybean meal (SBM). The 5 sources included hexane-extracted SBM produced from high-protein soybeans (SBM-HP) and conventional soybeans (SBM-CONV), and mechanically extruded-expelled SBM produced from high-protein soybeans (EE-SBM-HP), low-oligosaccharide soybeans (EE-SBM-LO), and conventional soybeans (EE-SBM-CONV). Five diets that each contained 1 source of SBM and a N-free diet were used in Exp. 1 to determine AA digestibility in each meal. Twelve growing barrows (initial BW: 67.7 +/- 1.34 kg) were allotted to a replicated 6 x 6 Latin square design with 6 periods and 6 diets in each square. Each period lasted 7 d, and ileal digesta were collected on d 6 and 7 of each period. Results of the experiment showed that the standardized ileal digestibility (SID) of all AA except Trp was similar for SBM-HP and SBM-CONV, but EE-SBM-HP and EE-SBM-LO had greater (P < 0.05) SID of His, Ile, Lys, Thr, and Val than EE-SBM-CONV. The SID of all indispensable AA in EE-SBM-HP was greater (P < 0.05) than in SBM-HP. The SID of Arg, Ile, Leu, and Phe in EE-SBM-CONV was greater (P < 0.05) than in SBM-CONV, but the SID of Trp was also greater (P < 0.05) in SBM-CONV than in EE-SBM-CONV. Experiment 2 was conducted to measure DE and ME in the same 5 sources of SBM as used in Exp. 1. Forty-eight growing barrows (initial BW: 38.6 +/- 3.46 kg) were placed in metabolism cages and randomly allotted to 6 diets with 8 replicates per diet. A corn-based diet and 5 diets based on a mixture of corn and each source of SBM were formulated. Urine and feces were collected during a 5-d collection period, and values for DE and ME in each source of SBM were calculated using the difference procedure. Results showed that the ME in SBM-HP tended to be greater (P = 0.10) than in SBM-CONV (4,074 vs. 3,672 kcal/kg of DM). The ME in EE-SBM-HP also tended to be greater (P = 0.10) than in EE-SBM-CONV and

  18. Borrelia burgdorferi EbfC defines a newly-identified, widespread family of bacterial DNA-binding proteins.

    Science.gov (United States)

    Riley, Sean P; Bykowski, Tomasz; Cooley, Anne E; Burns, Logan H; Babb, Kelly; Brissette, Catherine A; Bowman, Amy; Rotondi, Matthew; Miller, M Clarke; DeMoll, Edward; Lim, Kap; Fried, Michael G; Stevenson, Brian

    2009-04-01

    The Lyme disease spirochete, Borrelia burgdorferi, encodes a novel type of DNA-binding protein named EbfC. Orthologs of EbfC are encoded by a wide range of bacterial species, so characterization of the borrelial protein has implications that span the eubacterial kingdom. The present work defines the DNA sequence required for high-affinity binding by EbfC to be the 4 bp broken palindrome GTnAC, where 'n' can be any nucleotide. Two high-affinity EbfC-binding sites are located immediately 5' of B. burgdorferi erp transcriptional promoters, and binding of EbfC was found to alter the conformation of erp promoter DNA. Consensus EbfC-binding sites are abundantly distributed throughout the B. burgdorferi genome, occurring approximately once every 1 kb. These and other features of EbfC suggest that this small protein and its orthologs may represent a distinctive type of bacterial nucleoid-associated protein. EbfC was shown to bind DNA as a homodimer, and site-directed mutagenesis studies indicated that EbfC and its orthologs appear to bind DNA via a novel alpha-helical 'tweezer'-like structure.

  19. S-layer proteins from Lactobacillus sp. inhibit bacterial infection by blockage of DC-SIGN cell receptor.

    Science.gov (United States)

    Prado Acosta, Mariano; Ruzal, Sandra M; Cordo, Sandra M

    2016-11-01

    Many species of Lactobacillus sp. possess Surface(s) layer proteins in their envelope. Among other important characteristics S-layer from Lactobacillus acidophilus binds to the cellular receptor DC-SIGN (Dendritic Cell-Specific Intercellular adhesion molecule-3-Grabbing Non-integrin; CD209), which is involved in adhesion and infection of several families of bacteria. In this report we investigate the activity of new S-layer proteins from the Lactobacillus family (Lactobacillus acidophilus, Lactobacillus brevis, Lactobacillus helveticus and Lactobacillus kefiri) over the infection of representative microorganisms important to human health. After the treatment of DC-SIGN expressing cells with these proteins, we were able to diminish bacterial infection by up to 79% in both gram negative and mycobacterial models. We discovered that pre-treatment of the bacteria with S-layers from Lactobacillus acidophilus and Lactobacillus brevis reduced bacteria viability but also prevent infection by the pathogenic bacteria. We also proved the importance of the glycosylation of the S-layer from Lactobacillus kefiri in the binding to the receptor and thus inhibition of infection. This novel characteristic of the S-layers proteins may contribute to the already reported pathogen exclusion activity for these Lactobacillus probiotic strains; and might be also considered as a novel enzymatic antimicrobial agents to inhibit bacterial infection and entry to host cells.

  20. 酶法处理玉米胚芽粕提取蛋白质的条件初探%Preliminary Study on Conditions Related to Protein Extraction by Enzymatic Processing of Corn Germ Meal

    Institute of Scientific and Technical Information of China (English)

    杨丽; 王联结; 郑有为

    2011-01-01

    选用提油后的玉米胚芽粕为原料,利用纤维素酶对预处理后的胚芽粕进行水解,通过测定离心液中的糖量,残渣中纤维素水解率及浓缩后蛋白质含量等指标,考察胚芽粕预处理过程及酶解过程中几个主要因素对蛋白提取效果的影响.结果表明,预处理过程中4个因素对蛋白质提取效果影响的次序依次为:浸泡温度>浸泡时间>料液比>样品粒度.酶解过程中3个因素对蛋白质提取效果影响的次序依次为:加酶量>酶解时间>pH.结合正交试验的结果,同时考虑经济节约的原则,得到最佳组合为:浸泡温度35℃,浸泡时间48h,料液比1:12,粒度100目,加酶量2%,酶解时间48h,pH值4.5.最佳条件下测定产品中蛋白质含量可达42.5%.%Oil - extracted corn germ meal was selected as raw material and the pretreated germ meal was hydrolyzed with cellulase. The sugar content of the liquid, cellulose hydrolysis rate of the residue and the protein content of final product were measured to investigate the effects of several major factors in germ meal processing on protein extraction. The results showed that the effects of the pretreatment process factors on protein extraction followed the following order: soaking temperature > soaking time > liquid ratio > sample size. The effects of digestion process factors on the protein extraction sequence were as follows: enzyme dosage > hydrolysis time > pH. As per the results of the orthogonal test and on the basis of the economic saving principle,the best combination is as follows :liquid ratio 1: 12,soaking temperature 35 ℃ ,soaking time 48 h,particle size 100 mesh,enzyme 2% ,hydrolysis time 48h and pH value 4.5. Under the best conditions,the protein content of products reached to 42.5%.

  1. Recovery and techno-functionality of flours and proteins from two edible insect species: Meal worm (Tenebrio molitor and black soldier fly (Hermetia illucens larvae

    Directory of Open Access Journals (Sweden)

    Sara Bußler

    2016-12-01

    Full Text Available Depending on the species, edible insects are highly nutritious and thus represent a noteworthy alternative food and feed source. The current work investigates the protein extractability and techno-functionality of insect flour fractions recovered from Tenebrio molitor and Hermetia illucens. T. molitor and H. illucens flours contained about 20% crude fat and 60% and 36 % crude protein, respectively. Defatting reduced the crude fat content to 2.8% (T. molitor and 8.8% (H. illucens and increased the crude protein content to 68% and 47%, respectively. To isolate proteins from the flours, protein solubility was optimized by varying the pH, the ionic strength, and the extraction temperature of the solvent. All products and by-products accumulated in the protein production process were characterized by composition, selected techno-functional properties, protein solubility, composition and structure as well as their microbial load.

  2. Orally administered P22 phage tailspike protein reduces salmonella colonization in chickens: prospects of a novel therapy against bacterial infections.

    Directory of Open Access Journals (Sweden)

    Shakeeba Waseh

    Full Text Available One of the major causes of morbidity and mortality in man and economically important animals is bacterial infections of the gastrointestinal (GI tract. The emergence of difficult-to-treat infections, primarily caused by antibiotic resistant bacteria, demands for alternatives to antibiotic therapy. Currently, one of the emerging therapeutic alternatives is the use of lytic bacteriophages. In an effort to exploit the target specificity and therapeutic potential of bacteriophages, we examined the utility of bacteriophage tailspike proteins (Tsps. Among the best-characterized Tsps is that from the Podoviridae P22 bacteriophage, which recognizes the lipopolysaccharides of Salmonella enterica serovar Typhimurium. In this study, we utilized a truncated, functionally equivalent version of the P22 tailspike protein, P22sTsp, as a prototype to demonstrate the therapeutic potential of Tsps in the GI tract of chickens. Bacterial agglutination assays showed that P22sTsp was capable of agglutinating S. Typhimurium at levels similar to antibodies and incubating the Tsp with chicken GI fluids showed no proteolytic activity against the Tsp. Testing P22sTsp against the three major GI proteases showed that P22sTsp was resistant to trypsin and partially to chymotrypsin, but sensitive to pepsin. However, in formulated form for oral administration, P22sTsp was resistant to all three proteases. When administered orally to chickens, P22sTsp significantly reduced Salmonella colonization in the gut and its further penetration into internal organs. In in vitro assays, P22sTsp effectively retarded Salmonella motility, a factor implicated in bacterial colonization and invasion, suggesting that the in vivo decolonization ability of P22sTsp may, at least in part, be due to its ability to interfere with motility… Our findings show promise in terms of opening novel Tsp-based oral therapeutic approaches against bacterial infections in production animals and potentially in

  3. Variations in the binding pocket of an inhibitor of the bacterial division protein FtsZ across genotypes and species.

    Directory of Open Access Journals (Sweden)

    Amanda Miguel

    2015-03-01

    Full Text Available The recent increase in antibiotic resistance in pathogenic bacteria calls for new approaches to drug-target selection and drug development. Targeting the mechanisms of action of proteins involved in bacterial cell division bypasses problems associated with increasingly ineffective variants of older antibiotics; to this end, the essential bacterial cytoskeletal protein FtsZ is a promising target. Recent work on its allosteric inhibitor, PC190723, revealed in vitro activity on Staphylococcus aureus FtsZ and in vivo antimicrobial activities. However, the mechanism of drug action and its effect on FtsZ in other bacterial species are unclear. Here, we examine the structural environment of the PC190723 binding pocket using PocketFEATURE, a statistical method that scores the similarity between pairs of small-molecule binding sites based on 3D structure information about the local microenvironment, and molecular dynamics (MD simulations. We observed that species and nucleotide-binding state have significant impacts on the structural properties of the binding site, with substantially disparate microenvironments for bacterial species not from the Staphylococcus genus. Based on PocketFEATURE analysis of MD simulations of S. aureus FtsZ bound to GTP or with mutations that are known to confer PC190723 resistance, we predict that PC190723 strongly prefers to bind Staphylococcus FtsZ in the nucleotide-bound state. Furthermore, MD simulations of an FtsZ dimer indicated that polymerization may enhance PC190723 binding. Taken together, our results demonstrate that a drug-binding pocket can vary significantly across species, genetic perturbations, and in different polymerization states, yielding important information for the further development of FtsZ inhibitors.

  4. Use of biofuel by-product from the green algae Desmochloris sp. and diatom Nanofrustulum sp. meal in diets for nile tilapia Oreochromis niloticus

    Science.gov (United States)

    Algal by-product meals from the Hawaiian biofuels industry were evaluated as protein ingredients in diets for juveniles of Nile tilapia (Oreochromis niloticus). Four experimental diets were formulated to contain 40% protein and were made with fish meal, soybean meal, whole diatom (Nanofrustulum sp.)...

  5. Bio-Nanofabrication: Structuring Polymer Thin Films via Bacterial S-layer Proteins for Subsequent Use with Subtractive Nanofabrication Techniques

    Science.gov (United States)

    Esch, Mandy B.; Amponsah, Ebenezer K.; Bergkvist, Magnus

    2007-03-01

    Bio-molecule assisted lithography is a novel approach to create ordered patterns on the micro and nanometer size scale on thin films. The technique bears the potential to utilize self assembling properties of bio-molecules and to be integrated with conventional nanofabrication techniques. In the past, bacterial cell wall proteins (S-layers proteins) have been utilized to create ordered nanoparticle arrays. The work presented here employs S-layer proteins to shape UV-curable resist via an S-layer imprinted parylene template. Using this technique we can replicate S-layer patterns in resist thereby rendering the shape more resistant to subtractive nanofabrication techniques. The technique also demonstrates the adequacy of Nano Imprint Lithography to produce complex patterns not achievable with conventional lithography.

  6. Pigments and proteins in green bacterial chlorosomes studied by matrix-assisted laser desorption ionization mass spectrometry

    DEFF Research Database (Denmark)

    Persson, S; Sönksen, C P; Frigaard, N U;

    2000-01-01

    We have used matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS) for mass determination of pigments and proteins in chlorosomes, the light-harvesting organelles from the photosynthetic green sulfur bacterium Chlorobium tepidum. By applying a small volume (1...... proportional to peak areas obtained from HPLC analysis of the same sample. The same result was also obtained when whole cells of Chl. tepidum were applied to the target, indicating that MALDI-MS can provide a rapid method for obtaining a semiquantitative determination or finger-print of the bacteriochlorophyll...... homologs in a small amount of green bacterial cells. In addition to information on pigments, the MALDI spectra also contained peaks from chlorosome proteins. Thus we have been able with high precision to confirm the molecular masses of the chlorosome proteins CsmA and CsmE which have been previously...

  7. A census of membrane-bound and intracellular signal transduction proteins in bacteria: Bacterial IQ, extroverts and introverts

    Directory of Open Access Journals (Sweden)

    Galperin Michael Y

    2005-06-01

    Full Text Available Abstract Background Analysis of complete microbial genomes showed that intracellular parasites and other microorganisms that inhabit stable ecological niches encode relatively primitive signaling systems, whereas environmental microorganisms typically have sophisticated systems of environmental sensing and signal transduction. Results This paper presents results of a comprehensive census of signal transduction proteins – histidine kinases, methyl-accepting chemotaxis receptors, Ser/Thr/Tyr protein kinases, adenylate and diguanylate cyclases and c-di-GMP phosphodiesterases – encoded in 167 bacterial and archaeal genomes, sequenced by the end of 2004. The data have been manually checked to avoid false-negative and false-positive hits that commonly arise during large-scale automated analyses and compared against other available resources. The census data show uneven distribution of most signaling proteins among bacterial and archaeal phyla. The total number of signal transduction proteins grows approximately as a square of genome size. While histidine kinases are found in representatives of all phyla and are distributed according to the power law, other signal transducers are abundant in certain phylogenetic groups but virtually absent in others. Conclusion The complexity of signaling systems differs even among closely related organisms. Still, it usually can be correlated with the phylogenetic position of the organism, its lifestyle, and typical environmental challenges it encounters. The number of encoded signal transducers (or their fraction in the total protein set can be used as a measure of the organism's ability to adapt to diverse conditions, the 'bacterial IQ', while the ratio of transmembrane receptors to intracellular sensors can be used to define whether the organism is an 'extrovert', actively sensing the environmental parameters, or an 'introvert', more concerned about its internal homeostasis. Some of the microorganisms with the

  8. NbCSPR underlies age-dependent immune responses to bacterial cold shock protein in Nicotiana benthamiana.

    Science.gov (United States)

    Saur, Isabel M L; Kadota, Yasuhiro; Sklenar, Jan; Holton, Nicholas J; Smakowska, Elwira; Belkhadir, Youssef; Zipfel, Cyril; Rathjen, John P

    2016-03-22

    Plants use receptor kinases (RKs) and receptor-like proteins (RLPs) as pattern recognition receptors (PRRs) to sense pathogen-associated molecular patterns (PAMPs) that are typical of whole classes of microbes. After ligand perception, many leucine-rich repeat (LRR)-containing PRRs interact with the LRR-RK BRI1-ASSOCIATED KINASE 1 (BAK1). BAK1 is thus expected to interact with unknown PRRs. Here, we used BAK1 as molecular bait to identify a previously unknown LRR-RLP required for the recognition of the csp22 peptide derived from bacterial cold shock protein. We established a method to identify proteins that interact with BAK1 only after csp22 treatment. BAK1 was expressed transiently in Nicotiana benthamiana and immunopurified after treatment with csp22. BAK1-associated proteins were identified by mass spectrometry. We identified several proteins including known BAK1 interactors and a previously uncharacterized LRR-RLP that we termed RECEPTOR-LIKE PROTEIN REQUIRED FOR CSP22 RESPONSIVENESS (NbCSPR). This RLP associates with BAK1 upon csp22 treatment, and NbCSPR-silenced plants are impaired in csp22-induced defense responses. NbCSPR confers resistance to bacteria in an age-dependent and flagellin-induced manner. As such, it limits bacterial growth and Agrobacterium-mediated transformation of flowering N. benthamiana plants. Transgenic expression of NbCSPR into Arabidopsis thaliana conferred responsiveness to csp22 and antibacterial resistance. Our method may be used to identify LRR-type RKs and RLPs required for PAMP perception/responsiveness, even when the active purified PAMP has not been defined.

  9. Manipulating the glycosylation pathway in bacterial and lower eukaryotes for production of therapeutic proteins.

    Science.gov (United States)

    Anyaogu, Diana Chinyere; Mortensen, Uffe Hasbro

    2015-12-01

    The medical use of pharmaceutical proteins is rapidly increasing and cheap, fast and efficient production is therefore attractive. Microbial production hosts are promising candidates for development and production of pharmaceutical proteins. However, as most therapeutic proteins are secreted proteins, they are frequently N-glycosylated. This hampers production in microbes as these hosts glycosylate proteins differently. The resulting products may therefore be immunogenic, unstable and show reduced efficacy. Recently, successful glycoengineering of microbes has demonstrated that it is possible to produce proteins with humanlike glycan structures setting the stage for production of pharmaceutical proteins in bacteria, yeasts and algae.

  10. 固体发酵豆粕、菜粕和棉粕的复合菌筛选%Choose Complex Bacterium and Fungus as Fermentation Microform on Soybean Meal, Rapeseed Meal and Cottonseed Meal

    Institute of Scientific and Technical Information of China (English)

    邓露芳; 范学珊; 王加启

    2012-01-01

    试验根据豆粕、菜粕和棉粕作为植物性蛋白饲料的营养特性,选择中性蛋白酶活较高的细菌和真菌作为发酵豆粕、菜粕和棉粕的菌种以改善豆粕、菜粕和棉粕的蛋白质品质.通过细菌和真菌的两两组合生长试验,分别筛选出适合发酵豆粕、菜粕和棉粕的最佳复合菌各一组.试验结果表明,发酵豆粕、菜粕和棉粕的最佳菌株组合为BS-2和Ao、BS-natto和Ao、BS-natto和Ao.%Based on nutrition characters on soybean meal, rapeseed meal and cotton seed meal, high neutral enzyme production of bacteria and fungus were chose to inoculate in them to improve their protein quality as animal feed. Compounded one bacterium strain and one fungus strain cultured together, chose the best group to ferment the soybean meal, rapeseed meal and cotton seed meal. The results showed the best groups were BS-2 and Ao for soybean meal, BS-natto and Ao for rapeseed meal, and BS-natto and Ao for cotton seed meal.

  11. Oral mucosal lipids are antibacterial against Porphyromonas gingivalis, induce ultrastructural damage, and alter bacterial lipid and protein compositions.

    Science.gov (United States)

    Fischer, Carol L; Walters, Katherine S; Drake, David R; Dawson, Deborah V; Blanchette, Derek R; Brogden, Kim A; Wertz, Philip W

    2013-09-01

    Oral mucosal and salivary lipids exhibit potent antimicrobial activity for a variety of Gram-positive and Gram-negative bacteria; however, little is known about their spectrum of antimicrobial activity or mechanisms of action against oral bacteria. In this study, we examine the activity of two fatty acids and three sphingoid bases against Porphyromonas gingivalis, an important colonizer of the oral cavity implicated in periodontitis. Minimal inhibitory concentrations, minimal bactericidal concentrations, and kill kinetics revealed variable, but potent, activity of oral mucosal and salivary lipids against P. gingivalis, indicating that lipid structure may be an important determinant in lipid mechanisms of activity against bacteria, although specific components of bacterial membranes are also likely important. Electron micrographs showed ultrastructural damage induced by sapienic acid and phytosphingosine and confirmed disruption of the bacterial plasma membrane. This information, coupled with the association of treatment lipids with P. gingivalis lipids revealed via thin layer chromatography, suggests that the plasma membrane is a likely target of lipid antibacterial activity. Utilizing a combination of two-dimensional in-gel electrophoresis and Western blot followed by mass spectroscopy and N-terminus degradation sequencing we also show that treatment with sapienic acid induces upregulation of a set of proteins comprising a unique P. gingivalis stress response, including proteins important in fatty acid biosynthesis, metabolism and energy production, protein processing, cell adhesion and virulence. Prophylactic or therapeutic lipid treatments may be beneficial for intervention of infection by supplementing the natural immune function of endogenous lipids on mucosal surfaces.

  12. Oral mucosal lipids are antibacterial against Porphyromonas gingivalis, induce ultrastructural damage, and alter bacterial lipid and protein compositions

    Institute of Scientific and Technical Information of China (English)

    Carol L Fischer; Katherine S Walters; David R Drake; Deborah V Dawson; Derek R Blanchette; Kim A Brogden; Philip W Wertz

    2013-01-01

    Oral mucosal and salivary lipids exhibit potent antimicrobial activity for a variety of Gram-positive and Gram-negative bacteria;however, little is known about their spectrum of antimicrobial activity or mechanisms of action against oral bacteria. In this study, we examine the activity of two fatty acids and three sphingoid bases against Porphyromonas gingivalis, an important colonizer of the oral cavity implicated in periodontitis. Minimal inhibitory concentrations, minimal bactericidal concentrations, and kill kinetics revealed variable, but potent, activity of oral mucosal and salivary lipids against P. gingivalis, indicating that lipid structure may be an important determinant in lipid mechanisms of activity against bacteria, although specific components of bacterial membranes are also likely important. Electron micrographs showed ultrastructural damage induced by sapienic acid and phytosphingosine and confirmed disruption of the bacterial plasma membrane. This information, coupled with the association of treatment lipids with P. gingivalis lipids revealed via thin layer chromatography, suggests that the plasma membrane is a likely target of lipid antibacterial activity. Utilizing a combination of two-dimensional in-gel electrophoresis and Western blot followed by mass spectroscopy and N-terminus degradation sequencing we also show that treatment with sapienic acid induces upregulation of a set of proteins comprising a unique P. gingivalis stress response, including proteins important in fatty acid biosynthesis, metabolism and energy production, protein processing, cell adhesion and virulence. Prophylactic or therapeutic lipid treatments may be beneficial for intervention of infection by supplementing the natural immune function of endogenous lipids on mucosal surfaces.

  13. Antimicrobial proteins from snake venoms: direct bacterial damage and activation of innate immunity against Staphylococcus aureus skin infection.

    Science.gov (United States)

    Samy, R P; Stiles, B G; Gopalakrishnakone, P; Chow, V T K

    2011-01-01

    The innate immune system is the first line of defense against microbial diseases. Antimicrobial proteins produced by snake venoms have recently attracted significant attention due to their relevance to bacterial infection and potential development into new therapeutic agents. Staphylococcus aureus is one of the major human pathogens causing a variety of infections involving pneumonia, toxic shock syndrome, and skin lesions. With the recent emergence of methicillin (MRSA) and vancomycin (VRSA) resistance, S. aureus infection is a serious clinical problem that will have a grave socio-economic impact in the near future. Although S. aureus susceptibility to innate antimicrobial peptides has been reported recently, the protective effect of snake venom phospholipase A₂ (svPLA₂) proteins on the skin from S. aureus infection has been understudied. This review details the protective function of svPLA₂s derived from venoms against skin infections caused by S. aureus. We have demonstrated in vivo that local application of svPLA₂ provides complete clearance of S. aureus within 2 weeks after treatment compared to fusidic acid ointment (FAO). In vitro experiments also demonstrate that svPLA₂ proteins have inhibitory (bacteriostatic) and killing (bactericidal) effects on S. aureus in a dose-dependant manner. The mechanism of bacterial membrane damage and perturbation was clearly evidenced by electron microscopic studies. In summary, svPLA₂s from Viperidae and Elapidae snakes are novel molecules that can activate important mechanisms of innate immunity in animals to endow them with protection against skin infection caused by S. aureus.

  14. The topology of the bacterial co-conserved protein network and its implications for predicting protein function

    Directory of Open Access Journals (Sweden)

    Leach Sonia M

    2008-06-01

    Full Text Available Abstract Background Protein-protein interactions networks are most often generated from physical protein-protein interaction data. Co-conservation, also known as phylogenetic profiles, is an alternative source of information for generating protein interaction networks. Co-conservation methods generate interaction networks among proteins that are gained or lost together through evolution. Co-conservation is a particularly useful technique in the compact bacteria genomes. Prior studies in yeast suggest that the topology of protein-protein interaction networks generated from physical interaction assays can offer important insight into protein function. Here, we hypothesize that in bacteria, the topology of protein interaction networks derived via co-conservation information could similarly improve methods for predicting protein function. Since the topology of bacteria co-conservation protein-protein interaction networks has not previously been studied in depth, we first perform such an analysis for co-conservation networks in E. coli K12. Next, we demonstrate one way in which network connectivity measures and global and local function distribution can be exploited to predict protein function for previously uncharacterized proteins. Results Our results showed, like most biological networks, our bacteria co-conserved protein-protein interaction networks had scale-free topologies. Our results indicated that some properties of the physical yeast interaction network hold in our bacteria co-conservation networks, such as high connectivity for essential proteins. However, the high connectivity among protein complexes in the yeast physical network was not seen in the co-conservation network which uses all bacteria as the reference set. We found that the distribution of node connectivity varied by functional category and could be informative for function prediction. By integrating of functional information from different annotation sources and using the

  15. The liposoluble proteome of Mycoplasma agalactiae: an insight into the minimal protein complement of a bacterial membrane

    Directory of Open Access Journals (Sweden)

    Cacciotto Carla

    2010-08-01

    Full Text Available Abstract Background Mycoplasmas are the simplest bacteria capable of autonomous replication. Their evolution proceeded from gram-positive bacteria, with the loss of many biosynthetic pathways and of the cell wall. In this work, the liposoluble protein complement of Mycoplasma agalactiae, a minimal bacterial pathogen causing mastitis, polyarthritis, keratoconjunctivitis, and abortion in small ruminants, was subjected to systematic characterization in order to gain insights into its membrane proteome composition. Results The selective enrichment for M. agalactiae PG2T liposoluble proteins was accomplished by means of Triton X-114 fractionation. Liposoluble proteins were subjected to 2-D PAGE-MS, leading to the identification of 40 unique proteins and to the generation of a reference 2D map of the M. agalactiae liposoluble proteome. Liposoluble proteins from the type strain PG2 and two field isolates were then compared by means of 2D DIGE, revealing reproducible differences in protein expression among isolates. An in-depth analysis was then performed by GeLC-MS/MS in order to achieve a higher coverage of the liposoluble proteome. Using this approach, a total of 194 unique proteins were identified, corresponding to 26% of all M. agalactiae PG2T genes. A gene ontology analysis and classification for localization and function was also carried out on all protein identifications. Interestingly, the 11.5% of expressed membrane proteins derived from putative horizontal gene transfer events. Conclusions This study led to the in-depth systematic characterization of the M. agalactiae liposoluble protein component, providing useful insights into its membrane organization.

  16. Activation of the unfolded protein response is required for defenses against bacterial pore-forming toxin in vivo.

    Directory of Open Access Journals (Sweden)

    Larry J Bischof

    2008-10-01

    Full Text Available Pore-forming toxins (PFTs constitute the single largest class of proteinaceous bacterial virulence factors and are made by many of the most important bacterial pathogens. Host responses to these toxins are complex and poorly understood. We find that the endoplasmic reticulum unfolded protein response (UPR is activated upon exposure to PFTs both in Caenorhabditis elegans and in mammalian cells. Activation of the UPR is protective in vivo against PFTs since animals that lack either the ire-1-xbp-1 or the atf-6 arms of the UPR are more sensitive to PFT than wild-type animals. The UPR acts directly in the cells targeted by the PFT. Loss of the UPR leads to a normal response against unrelated toxins or a pathogenic bacterium, indicating its PFT-protective role is specific. The p38 mitogen-activated protein (MAPK kinase pathway has been previously shown to be important for cellular defenses against PFTs. We find here that the UPR is one of the key downstream targets of the p38 MAPK pathway in response to PFT since loss of a functional p38 MAPK pathway leads to a failure of PFT to properly activate the ire-1-xbp-1 arm of the UPR. The UPR-mediated activation and response to PFTs is distinct from the canonical UPR-mediated response to unfolded proteins both in terms of its activation and functional sensitivities. These data demonstrate that the UPR, a fundamental intracellular pathway, can operate in intrinsic cellular defenses against bacterial attack.

  17. Interaction of Gram-negative bacteria with cationic proteins: Dependence on the surface characteristics of the bacterial cell

    Directory of Open Access Journals (Sweden)

    Isabella R Prokhorenko

    2009-03-01

    Full Text Available Isabella R Prokhorenko1, Svetlana V Zubova1, Alexandr Yu Ivanov2, Sergey V Grachev31Laboratory of Molecular Biomedicine, Institute of Basic Biological Problems; 2Institute of Cell Biophysics, Russian Academy of Sciences, Moscow, Russia; 3I.M. Sechenov’s Moscow Medical Academy, Moscow, Russia Abstract: Gram-negative bacteria can enter the bloodstream and interact with serum cationic proteins. The character of interaction will depend on the surface characteristics of bacterial cells, which are determined by bacterial chemotype and density of lipopolysaccharide (LPS packing in the cell wall. It was shown that the lysozyme treatment resulted in the increase sensitivity to hypotonic shock. Signifi cant differences to this effect were found between Escherichia coli strain D21 and D21f2 under treatment with physiological protein concentration. On the basis of electrokinetic measurements and studies of the interaction of cells with lysozyme, the hypothesis was formed that the cell wall of the E. coli strain D21f2 contains more LPS and has a higher density of their packing than the cell wall of the E. coli D21 cells. The effect of lysozyme and lactoferrin on the viability of E. coli cells of two different strains was examined. Lysozyme was found to more effectively inhibit the growth of the E. coli D21 bacteria, and lactoferrin suppressed mainly the growth of the E. coli D21f2 bacteria. These results indicate that the differences in LPS core structure of bacterial R-chemotype, which determines surface charge and density of LPS packing, plays an essential role in the mechanisms of interaction of the cationic proteins with the cell wall.Keywords: lipopolysaccharide, Escherichia coli, chemotype, lysozyme, lactoferrin, colony-forming units

  18. Performance of broilers fed with snail (Pomacea caniculata meal as substitute to fish meal or meat and bone meal

    Directory of Open Access Journals (Sweden)

    Ulep, LJL.

    1991-01-01

    Full Text Available Snail meal was used as a substitution to fish meat and bone meal in broiler rations. Final weightand feed conversion efficiency of the birds, profit and return on investment differed significantly among treatments. Feed consumption and production costs were comparable. Results show that snail meal can replace fish or meat and bone meal in broiler diets.

  19. Ruminal Degradability of Dry Matter and Crude Protein from Moist Dehulled Lupin and Extruded Rapeseed Meal Degradabilidad Ruminal de la Materia Seca y de la Proteína Cruda de Lupino Descascarado y Torta de Raps Extruidos

    Directory of Open Access Journals (Sweden)

    Claudia Barchiesi-Ferrari

    2011-09-01

    Full Text Available The flow of ruminal undegradable protein (RUP to the small intestine can be increased if ruminal degradation of dietary protein is reduced. The objective of this study was to evaluate the effect of extrusion on ruminal degradability of dry matter (DM and crude protein (CP from dehulled lupin (Lupinus albus L. (DL and rapeseed (Brassica napus L. meal (RM. Unextruded soybean (Glicine max L. meal (SBM was used as a control. The DL was extruded at 130 ºC with 20% moisture and RM was extruded at 120 ºC with 20% moisture. Ruminal degradability was evaluated in situ by incubating feed samples for 2, 4, 8, 12, 24, and 48 h of fermentation in the rumen using three rumen-fistulated dairy cows. Values of CP soluble fraction (“a” in SBM, DL, extruded dehulled lupin (EDL, RM, and extruded rapeseed meal (ERM was lower in the extruded feeds (P El flujo de proteína no degradable en el rumen (RUP hacia el intestino delgado puede ser incrementado si se reduce la degradación ruminal de la proteína dietaria. El objetivo de este trabajo fue evaluar el efecto de la extrusión sobre la degradabilidad ruminal de la materia seca (DM y proteína cruda (CP de lupino (Lupinus albus L. descascarado (DL y torta de raps (Brassica napus L. (RM. Se utilizó afrecho de soya (Glicine max L. sin extruir (SBM como control. El DL fue extruido a 130 ºC con 20% de humedad y la RM fue extruida a 120 ºC con 20% de humedad. La degradabilidad ruminal se evaluó in situ incubando las muestras de alimentos a 2, 4, 8, 12, 24 y 48 h de fermentación en tres vacas lecheras con fístula ruminal. Los valores de la fracción soluble de la CP (“a” en SBM, en DL, lupino descascarado extruido (EDL, RM y torta de raps extruida (ERM fue menor en los extruidos (P < 0.05. La fracción lentamente degradable (“b” de SBM, DL, EDL, RM y de ERM fue 858; 593; 622 y 451 y 457 g kg-1, respectivamente, y se incrementó por extrusión (P < 0.05. La extrusión redujo la degradabilidad efectiva

  20. The quality of meal elements for professional prepared meals

    DEFF Research Database (Denmark)

    Løje, Hanne; Adler-Nissen, Jens

    Meal elements are convenience products which are partially prepared meal components to be used in professional kitchens. Examples are meat, vegetables or fish which are preprepared for example by heat-treatment before distribution to the professional kitchens. The pre-fried vegetables and meat can...... robust against freezing, thawing and reheating without excessive drip losses as observed from raw or blanched vegetables. The results show that the pre-fried vegetables have a potential to be used as meal elements for professional prepared meals....... for examples be used as ingredients in hot or cold dishes. We have evaluated the quality of several kinds of pre-fried vegetables. The vegetables were prepared in pilot plan using a continuous stir-frying process, frozen and analysis during the thawing period. The results show that the shelf life determined...

  1. Strategies for production of active eukaryotic proteins in bacterial expression system

    Institute of Scientific and Technical Information of China (English)

    Orawan Khow; Sunutcha Suntrarachun

    2012-01-01

    Bacteria have long been the favorite expression system for recombinant protein production. However, the flaw of the system is that insoluble and inactive proteins are co-produced due to codon bias, protein folding, phosphorylation, glycosylation, mRNA stability and promoter strength. Factors are cited and the methods to convert to soluble and active proteins are described, for example a tight control of Escherichia coli milieu, refolding from inclusion body and through fusion technology.

  2. Comparison of amino acid digestibility coefficients for soybean meal, canola meal, fish meal, and meat and bone meal among 3 different bioassays

    Science.gov (United States)

    The objective of this study was to determine amino acid digestibility of 4 feedstuffs [soybean meal (SBM), canola meal, fish meal, and meat and bone meal (MBM)] using the precision-fed cecectomized rooster assay (PFR), the standardized ileal assay (SIAAD), and a newly developed precision-fed ileal b...

  3. Intrinsic disorder of the bacterial cell division protein ZipA: coil-to-brush conformational transition.

    Science.gov (United States)

    López-Montero, Iván; López-Navajas, Pilar; Mingorance, Jesús; Rivas, Germán; Vélez, Marisela; Vicente, Miguel; Monroy, Francisco

    2013-08-01

    The full-length ZipA protein from Escherichia coli, one of the essential elements of the cell division machinery, was studied in a surface model built as adsorbed monolayers. The interplay between lateral packing and molecular conformation was probed using a combined methodology based on the scaling analysis of the surface pressure isotherms and ellipsometry measurements of the monolayer thickness. The observed behavior is compatible with the one expected for an intrinsically disordered and highly flexible protein that is preferentially structured in a random coil conformation. At low grafting densities, ZipA coils organize in a mushroom-like regime, whereas a coil-to-brush transition occurs on increasing lateral packing. The structural results suggest a functional scenario in which ZipA acts as a flexible tether anchoring bacterial proto-ring elements to the membrane during the earlier stages of division.

  4. Effects of a dietary mixture of meat and bone meal, feather meal, blood meal, and fish meal on nitrogen utilization in finishing Holstein steers.

    Science.gov (United States)

    Knaus, W F; Beermann, D H; Robinson, T F; Fox, D G; Finnerty, K D

    1998-05-01

    Our objective was to determine to what extent rate and efficiency of protein gain in finishing cattle can be enhanced by feeding an amino acid-balanced mixture of undegraded intake proteins. The Cornell Net Carbohydrate and Protein System (CNCPS) model was used to formulate a corn-based diet that would meet the rumen requirements for 410-kg large-framed steers with an estrogen implant and fed an ionophore. The CNCPS model was also used to formulate a highly undegradable intake protein (UIP) mixture from meat and bone meal, blood meal, fish meal, and hydrolyzed feather meal to provide the amino acids needed to supplement those derived from microbial protein to better meet amino acid requirements for growth. Four Holstein steers weighing 407 kg were offered a 90:10 concentrate-forage diet at hourly intervals at 95% of ad libitum intake. The steers were injected with 500 microg of estradiol-17beta at 12-h intervals to mimic the effects of an estrogenic implant. Treatments planned consisted of inclusion of the UIP mixture at 0, 2.5, 5, and 7.5% of the diet DM. Dry matter intake was fixed at 6.4 kg/d, and DM digestibility was not significantly affected by varying the amount of UIP addition. Apparent digestibility of N increased (P = .011) from 63.8 to 65.8, 70.7, and 71.5%, the amount of N absorbed increased (P = .001) from 73 to 84, 100, and 106 g/d, and N balance increased (P = .003) from 20 to 30, 33, and 39 g/d when UIP was fed at 0, 2.6, 5.2, and 7.8% of diet DM, respectively. The efficiency of N use increased 39.7%, and biological value increased 31.6% when the UIP mixture was added to the diet. Circulating concentrations of plasma urea N (PUN) were increased (P = .017) from 4.5 for the control diet to 5.7, 6.2, and 6.1 mg/dL when the UIP mixture was added at 2.6, 5.2, and 7.8%, respectively. Corresponding IGF-I concentrations were also increased from 491 to 558 and 624 ng/mL with 2.6 and 5.2% levels of UIP addition. Plasma glucose, NEFA, and insulin

  5. Studies on Bacterial Proteins Corona Interaction with Saponin Imprinted ZnO Nanohoneycombs and Their Toxic Responses.

    Science.gov (United States)

    Sharma, Deepali; Ashaduzzaman, Md; Golabi, Mohsen; Shriwastav, Amritanshu; Bisetty, Krishna; Tiwari, Ashutosh

    2015-11-01

    Molecular imprinting generates robust, efficient, and highly mesoporous surfaces for biointeractions. Mechanistic interfacial interaction between the surface of core substrate and protein corona is crucial to understand the substantial microbial toxic responses at a nanoscale. In this study, we have focused on the mechanistic interactions between synthesized saponin imprinted zinc oxide nanohoneycombs (SIZnO NHs), average size 80-125 nm, surface area 20.27 m(2)/g, average pore density 0.23 pore/nm and number-average pore size 3.74 nm and proteins corona of bacteria. The produced SIZnO NHs as potential antifungal and antibacterial agents have been studied on Sclerotium rolfsii (S. rolfsii), Pythium debarynum (P. debarynum) and Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), respectively. SIZnO NHs exhibited the highest antibacterial (∼50%) and antifungal (∼40%) activity against Gram-negative bacteria (E. coli) and fungus (P. debarynum), respectively at concentration of 0.1 mol. Scanning electron spectroscopy (SEM) observation showed that the ZnO NHs ruptured the cell wall of bacteria and internalized into the cell. The molecular docking studies were carried out using binding proteins present in the gram negative bacteria (lipopolysaccharide and lipocalin Blc) and gram positive bacteria (Staphylococcal Protein A, SpA). It was envisaged that the proteins present in the bacterial cell wall were found to interact and adsorb on the surface of SIZnO NHs thereby blocking the active sites of the proteins used for cell wall synthesis. The binding affinity and interaction energies were higher in the case of binding proteins present in gram negative bacteria as compared to that of gram positive bacteria. In addition, a kinetic mathematical model (KMM) was developed in MATLAB to predict the internalization in the bacterial cellular uptake of the ZnO NHs for better understanding of their controlled toxicity. The results obtained from KMM exhibited a good

  6. A multiple information fusion method for predicting subcellular locations of two different types of bacterial protein simultaneously.

    Science.gov (United States)

    Chen, Jing; Xu, Huimin; He, Ping-An; Dai, Qi; Yao, Yuhua

    2016-01-01

    Subcellular localization prediction of bacterial protein is an important component of bioinformatics, which has great importance for drug design and other applications. For the prediction of protein subcellular localization, as we all know, lots of computational tools have been developed in the recent decades. In this study, we firstly introduce three kinds of protein sequences encoding schemes: physicochemical-based, evolutionary-based, and GO-based. The original and consensus sequences were combined with physicochemical properties. And elements information of different rows and columns in position-specific scoring matrix were taken into consideration simultaneously for more core and essence information. Computational methods based on gene ontology (GO) have been demonstrated to be superior to methods based on other features. Then principal component analysis (PCA) is applied for feature selection and reduced vectors are input to a support vector machine (SVM) to predict protein subcellular localization. The proposed method can achieve a prediction accuracy of 98.28% and 97.87% on a stringent Gram-positive (Gpos) and Gram-negative (Gneg) dataset with Jackknife test, respectively. At last, we calculate "absolute true overall accuracy (ATOA)", which is stricter than overall accuracy. The ATOA obtained from the proposed method is also up to 97.32% and 93.06% for Gpos and Gneg. From both the rationality of testing procedure and the success rates of test results, the current method can improve the prediction quality of protein subcellular localization.

  7. High Protein Pasta is Not More Satiating than High Fiber Pasta at a Lunch Meal, Nor Does it Decrease Mid-Afternoon Snacking in Healthy Men and Women.

    Science.gov (United States)

    Korczak, Renee; Timm, Derek; Ahnen, Rylee; Thomas, William; Slavin, Joanne L

    2016-09-01

    This study compared satiety after high protein pasta (16 g protein, 6 g fiber), high fiber pasta (11 g protein, 8 g fiber) or control pasta (11 g protein, 6 g fiber) in a randomized, placebo-controlled, double-blind crossover trial. Participants were 36 healthy and men and women from the University of Minnesota campus. Fasted men and women ate calorie controlled, but macronutrient different pastas at 12:00 pm along with 500 mL of water. The primary outcome was satiety assessed by Visual Analogue Scales at 0, 15, 30, 45, 60, 90, 120, and 180 min daily after consuming the pastas. Secondary outcomes were calories consumed at an ad libitum snack at 3:00 pm, calories from food intake, gastrointestinal tolerance, and palatability. No differences were found among the pasta treatments for satiety, snacking, or gastrointestinal tolerance. Men ate significantly more calories for the rest of the (P = 0.007) after the high protein pasta versus the high fiber pasta (1701 ± 154 compared with 1083 ± 154) with control pasta being intermediate to the other treatments. No significant differences were found for gastrointestinal tolerance, but the palatability ratings showed the high protein pasta was less tasty (P = 0.03) and less pleasant (P = 0.01) than the other 2 pastas. Satisfaction was positively associated with pleasantness and negatively associated with aftertaste. Our results do not support the idea that high protein or high fiber pasta produces a greater satiety response compared to pasta with lower amounts of either nutrient. It is likely that since pasta is already a very satiating food, the subjects were unable to differentiate between the 3 conditions.

  8. A high-throughput method to examine protein-nucleotide interactions identifies targets of the bacterial transcriptional regulatory protein fur.

    Science.gov (United States)

    Yu, Chunxiao; Lopez, Carlos A; Hu, Han; Xia, Yu; Freedman, David S; Reddington, Alexander P; Daaboul, George G; Unlü, M Selim; Genco, Caroline Attardo

    2014-01-01

    The Ferric uptake regulatory protein (Fur) is a transcriptional regulatory protein that functions to control gene transcription in response to iron in a number of pathogenic bacteria. In this study, we applied a label-free, quantitative and high-throughput analysis method, Interferometric Reflectance Imaging Sensor (IRIS), to rapidly characterize Fur-DNA interactions in vitro with predicted Fur binding sequences in the genome of Neisseria gonorrhoeae, the causative agent of the sexually transmitted disease gonorrhea. IRIS can easily be applied to examine multiple protein-protein, protein-nucleotide and nucleotide-nucleotide complexes simultaneously and demonstrated here that seventy percent of the predicted Fur boxes in promoter regions of iron-induced genes bound to Fur in vitro with a range of affinities as observed using this microarray screening technology. Combining binding data with mRNA expression levels in a gonococcal fur mutant strain allowed us to identify five new gonococcal genes under Fur-mediated direct regulation.

  9. Process Development for Spray Drying a Value-Added Extract from Aflatoxin Contaminated Peanut Meal

    Science.gov (United States)

    Peanut meal, the primary byproduct of commercial oil crushing operations, is an excellent source of protein though aflatoxin contamination often limits applications for this material. Naturally aflatoxin contaminated (59 ppb) peanut meal dispersions were adjusted to pH 2.1 or pH 9.1, with or without...

  10. Optimizing fish meal-free commercial diets for Nile Tilapia, Oreochromis niloticus

    Science.gov (United States)

    A feeding trial was conducted in a closed recirculating aquaculture system with Nile tilapia Oreochromis niloticus juveniles (mean weight, 6.81 g) to examine the response to a practical diet containing protein primarily from menhaden fish meal (FM) and soybean meal (SBM) (control, Diet 1) or to diet...

  11. Inflammatory and metabolic responses to high-fat meals with and without dairy products in men.

    Science.gov (United States)

    Schmid, Alexandra; Petry, Nicolai; Walther, Barbara; Bütikofer, Ueli; Luginbühl, Werner; Gille, Doreen; Chollet, Magali; McTernan, Philip G; Gijs, Martin A M; Vionnet, Nathalie; Pralong, François P; Laederach, Kurt; Vergères, Guy

    2015-06-28

    Postprandial inflammation is an important factor for human health since chronic low-grade inflammation is associated with chronic diseases. Dairy products have a weak but significant anti-inflammatory effect on postprandial inflammation. The objective of the present study was to compare the effect of a high-fat dairy meal (HFD meal), a high-fat non-dairy meal supplemented with milk (HFM meal) and a high-fat non-dairy control meal (HFC meal) on postprandial inflammatory and metabolic responses in healthy men. A cross-over study was conducted in nineteen male subjects. Blood samples were collected before and 1, 2, 4 and 6 h after consumption of the test meals. Plasma concentrations of insulin, glucose, total cholesterol, LDL-cholesterol, HDL-cholesterol, TAG and C-reactive protein (CRP) were measured at each time point. IL-6, TNF-α and endotoxin concentrations were assessed at baseline and endpoint (6 h). Time-dependent curves of these metabolic parameters were plotted, and the net incremental AUC were found to be significantly higher for TAG and lower for CRP after consumption of the HFM meal compared with the HFD meal; however, the HFM and HFD meals were not different from the HFC meal. Alterations in IL-6, TNF-α and endotoxin concentrations were not significantly different between the test meals. The results suggest that full-fat milk and dairy products (cheese and butter) have no significant impact on the inflammatory response to a high-fat meal.

  12. Immunotoxicity of nucleic acid reduced BioProtein - a bacterial derived single cell protein - in Wistar rats

    DEFF Research Database (Denmark)

    Mølck, Anne-marie; Poulsen, Morten; Christensen, Hanne Risager;

    2002-01-01

    BioProtein is a single cell protein produced by a mixed methanotrophic and heterotrophic bacteria culture using natural gas as energy source, which has been approved for animal feed. BioProtein contains a large amount of nucleic acids making the product less suitable for human consumption...... the same tendency, although, not statistically significant (P = 0.09). The subsets of cells identified as neutrophils and eosinophils were increased and lymphocytes decreased. The histopathological examination revealed histiocytosis and accumulation of foamy macrophages in the mesenteric lymph nodes...

  13. Engineering bacterial surface displayed human norovirus capsid proteins: A novel system to explore interaction between norovirus and ligands

    Directory of Open Access Journals (Sweden)

    Mengya eNiu

    2015-12-01

    Full Text Available Human noroviruses (HuNoVs are major contributors to acute nonbacterial gastroenteritis outbreaks. Many aspects of HuNoVs are poorly understood due to both the current inability to culture HuNoVs, and the lack of efficient small animal models. Surrogates for HuNoVs, such as recombinant viral like particles (VLPs expressed in eukaryotic system or P particles expressed in prokaryotic system, have been used for studies in immunology and interaction between the virus and its receptors. However, it is difficult to use VLPs or P particles to collect or isolate potential ligands binding to these recombinant capsid proteins. In this study, a new strategy was used to collect HuNoVs binding ligands through the use of ice nucleation protein (INP to display recombinant capsid proteins of HuNoVs on bacterial surfaces. The viral protein-ligand complex could be easily separated by a low speed centrifugation step. This system was also used to explore interaction between recombinant capsid proteins of HuNoVs and their receptors. In this system, the VP1 capsid encoding gene (ORF2 and the protruding domain (P domain encoding gene (3’ terminal fragment of ORF2 of HuNoVs GI.1 and GII.4 were fused with 5’ terminal fragment of ice nucleation protein encoding gene (inaQn. The results demonstrated that the recombinant VP1 and P domains of HuNoVs were expressed and anchored on the surface of Escherichia coli BL21 cells after the bacteria were transformed with the corresponding plasmids. Both cell surface displayed VP1 and P domains could be recognized by HuNoVs specific antibodies and interact with the viral histo-blood group antigens receptors. In both cases, displayed P domains had better binding abilities than VP1. This new strategy of using displayed HuNoVs capsid proteins on the bacterial surface could be utilized to separate HuNoVs binding components from complex samples, to investigate interaction between the virus and its receptors, as well as to develop an

  14. In pursuit of protein targets: proteomic characterization of bacterial spore outer layers.

    Science.gov (United States)

    Abhyankar, Wishwas; Hossain, Abeer H; Djajasaputra, André; Permpoonpattana, Patima; Ter Beek, Alexander; Dekker, Henk L; Cutting, Simon M; Brul, Stanley; de Koning, Leo J; de Koster, Chris G

    2013-10-04

    Bacillus cereus, responsible for food poisoning, and Clostridium difficile, the causative agent of Clostridium difficile-associated diarrhea (CDAD), are both spore-forming pathogens involved in food spoilage, food intoxication, and other infections in humans and animals. The proteinaceous coat and the exosporium layers from spores are important for their resistance and pathogenicity characteristics. The exosporium additionally provides an ability to adhere to surfaces eventually leading to spore survival in food. Thus, studying these layers and identifying suitable protein targets for rapid detection and removal of spores is of the utmost importance. In this study, we identified 100 proteins from B. cereus spore coat, exosporium and 54 proteins from the C. difficile coat insoluble protein fraction. In an attempt to define a universal set of spore outer layer proteins, we identified 11 superfamily domains common to the identified proteins from two Bacilli and one Clostridium species. The evaluated orthologue relationships of identified proteins across different spore formers resulted in a set of 13 coat proteins conserved across the spore formers and 12 exosporium proteins conserved in the B. cereus group, which could be tested for quick and easy detection or targeted in strategies aimed at removal of spores from surfaces.

  15. A model for the condensation of the bacterial chromosome by the partitioning protein ParB

    Science.gov (United States)

    Broedersz, Chase; Wingreen, Ned

    2013-03-01

    The molecular machinery responsible for faithful segregation of the chromosome in bacteria such as Caulobacter crescentus and Bacillus subtilis includes the ParABS a.k.a. Spo0J/Soj partitioning system. In Caulobacter, prior to division, hundreds of ParB proteins bind to the DNA near the origin of replication, and localize to one pole of the cell. Subsequently, the ParB-DNA complex is translocated to the far pole by the binding and retraction of the ParA spindle-like apparatus. Remarkably, the localization of ParB proteins to specific regions of the chromosome appears to be controlled by only a few centromeric parS binding sites. Although lateral interactions between DNA-bound ParB are likely to be important for their localization, the long-range order of ParB domains on the chromosome appears to be inconsistent with a picture in which protein-protein interactions are limited to neighboring DNA-bound proteins. We developed a coarse-grained Brownian dynamics model that allows for lateral and 3D protein-protein interactions among bound ParB proteins. Our model shows how such interactions can condense and organize the DNA spatially, and can control the localization and the long-range order of the DNA-bound proteins.

  16. Proteome-wide identification of predominant subcellular protein localizations in a bacterial model organism

    Energy Technology Data Exchange (ETDEWEB)

    Stekhoven, Daniel J. [Univ. of Zurich (Switzerland); Omasits, Ulrich [Univ. of Zurich (Switzerland); ETH Zurich (Switzerland); Quebatte, Maxime [Univ. of Basel (Switzerland); Dehio, Christoph [Univ. of Basel (Switzerland); Ahrens, Christian H. [Univ. of Zurich (Switzerland)

    2014-03-01

    Proteomics data provide unique insights into biological systems, including the predominant subcellular localization (SCL) of proteins, which can reveal important clues about their functions. Here we analyzed data of a complete prokaryotic proteome expressed under two conditions mimicking interaction of the emerging pathogen Bartonella henselae with its mammalian host. Normalized spectral count data from cytoplasmic, total membrane, inner and outer membrane fractions allowed us to identify the predominant SCL for 82% of the identified proteins. The spectral count proportion of total membrane versus cytoplasmic fractions indicated the propensity of cytoplasmic proteins to co-fractionate with the inner membrane, and enabled us to distinguish cytoplasmic, peripheral innermembrane and bona fide inner membrane proteins. Principal component analysis and k-nearest neighbor classification training on selected marker proteins or predominantly localized proteins, allowed us to determine an extensive catalog of at least 74 expressed outer membrane proteins, and to extend the SCL assignment to 94% of the identified proteins, including 18% where in silico methods gave no prediction. Suitable experimental proteomics data combined with straightforward computational approaches can thus identify the predominant SCL on a proteome-wide scale. Finally, we present a conceptual approach to identify proteins potentially changing their SCL in a condition-dependent fashion.

  17. Exploring structure and interactions of the bacterial adaptor protein YjbH by crosslinking mass spectrometry

    DEFF Research Database (Denmark)

    Al-Eryani, Yusra; Ib Rasmussen, Morten; Kjellström, Sven;

    2016-01-01

    Adaptor proteins assist proteases in degrading specific proteins under appropriate conditions. The adaptor protein YjbH promotes the degradation of an important global transcriptional regulator Spx, which controls the expression of hundreds of genes and operons in response to thiol-specific oxida......Adaptor proteins assist proteases in degrading specific proteins under appropriate conditions. The adaptor protein YjbH promotes the degradation of an important global transcriptional regulator Spx, which controls the expression of hundreds of genes and operons in response to thiol......-specific oxidative stress in Bacillus subtilis. Under normal growth conditions, the transcription factor is bound to the adaptor protein and therefore degraded by the AAA+ protease ClpXP. If this binding is alleviated during stress, the transcription factor accumulates and turns on genes encoding stress...... and validate a structure model of YjbH and then to probe its interactions with other proteins. The core structure of YjbH is reminiscent of DsbA family proteins. One lysine residue in YjbH (K177), located in one of the α-helices outside the thioredoxin fold, crosslinked to both Spx K99 and Spx K117, thereby...

  18. A common theme in interaction of bacterial immunoglobulin-binding proteins with immunoglobulins illustrated in the equine system.

    Science.gov (United States)

    Lewis, Melanie J; Meehan, Mary; Owen, Peter; Woof, Jenny M

    2008-06-20

    The M protein of Streptococcus equi subsp. equi known as fibrinogen-binding protein (FgBP) is a cell wall-associated protein with antiphagocytic activity that binds IgG. Recombinant versions of the seven equine IgG subclasses were used to investigate the subclass specificity of FgBP. FgBP bound predominantly to equine IgG4 and IgG7, with little or no binding to the other subclasses. Competitive binding experiments revealed that FgBP could inhibit the binding of staphylococcal protein A and streptococcal protein G to both IgG4 and IgG7, implicating the Fc interdomain region in binding to FgBP. To identify which of the two IgG Fc domains contributed to the interaction with FgBP, we tested two human IgG1/IgA1 domain swap mutants and found that both domains are required for full binding, with the CH3 domain playing a critical role. The binding site for FgBP was further localized using recombinant equine IgG7 antibodies with single or double point mutations to residues lying at the CH2-CH3 interface. We found that interaction of FgBP with equine IgG4 and IgG7 was able to disrupt C1q binding and antibody-mediated activation of the classical complement pathway, demonstrating an effective means by which S. equi may evade the immune response. The mode of interaction of FgBP with IgG fits a common theme for bacterial Ig-binding proteins. Remarkably, for those interactions studied in detail, it emerges that all the Ig-binding proteins target the CH2-CH3 domain interface, regardless of specificity for IgG or IgA, streptococcal or staphylococcal origin, or host species (equine or human).

  19. Bacterial expression and isotope labeling of AIMP1/p43 codosome protein for structural studies by multidimensional NMR spectroscopy

    Directory of Open Access Journals (Sweden)

    Vorobyova N. V.

    2015-04-01

    Full Text Available AIMP1/p43 protein is a structural component of multisynthetase complex (codosome in eukaryotes, which reveals both tRNA binding and cytokine activities. Aim. Bacterial expression and purification of isotopically-labeled recombinant AIMP1/p43 protein in E. coli cells for studying its solution structure by multidimensional NMR spectroscopy. Methods. AIMP1/p43 protein was expressed in E. coli BL21(DE3pLysE cells on M9 minimal medium with 15N isotope labeling and purified by metal-chelated chromatography. Heteronuclear 2D 1H-15N NMR experiments were performed in solution at 293 K on Agilent DDR2 800 NMR spectrometer. Results. The AIMP1/p43 protein was obtained in uniformly 15N-labeled form as an NMR sample. A high dispersion of resonance signals in the 2D 1H-15N HSQC NMR spectra confirmed the presence of its compact 3D protein structure. The NMR spectrum of AIMP1/p43 demonstrated a high signal-to-noise ratio and sufficient stability to acquire other multidimensional NMR data sets for determination of the structure of AIMP1/p43 protein in solution. Conclusions. The 15N-labeled AIMP1/p43 protein was stable for 4–7 days, which makes possible acquiring the critical NMR experimental data for detailed structural analysis in solution. Our data on the initial NMR spectra indicated the presence of some additional signals in comparison with the NMR spectrum of EMAP II which could be assigned to amino acids of the N-terminal α-helical fragment of AIMP1/p43.

  20. Effects of Cooking and Screw-Pressing on Functional Properties of Protein in Milkweed (Asclepias spp.) Seed Meals and Press Cakes

    Science.gov (United States)

    This study determined the effects of oil processing conditions on functional properties of milkweed seed proteins to evaluate their potential for value-added uses. Flaked milkweed seeds were cooked at 82 degrees C (180 degrees F) for 30, 60 or 90 min in the seed conditioner, and then screw-pressed ...

  1. Desempenho de leitões submetidos a diferentes níveis de substituição da proteína do farelo de soja pela proteína do ovo desidratado = Performance of piglets submitted to different replacement levels of soybean meal protein by dehydrated egg protein

    Directory of Open Access Journals (Sweden)

    Janaína de Cássia Braga Arruda

    2008-10-01

    Full Text Available Objetivou-se determinar o ganho de peso, o consumo de ração e a conversão alimentar de suínos em fase inicial (15 a 30 kg de peso alimentados com quatro diferentes níveis de substituição (0, 3, 6 e 9% da proteína do farelo de soja pela proteína do ovo desidratado. Foram utilizados 32 suínos (16 machos castrados e 16 fêmeas em um delineamento em blocos casualizados, com quatro tratamentos e quatro repetições cada, em que a unidade experimental foi composta por um macho e uma fêmea. Os tratamentos foram 0, 3, 6 e 9% de proteína do ovo desidratado em substituição à proteína do farelo de soja. Os dados obtidos foram submetidos à regressão linear para os níveis de 3, 6 e 9% de ovo desidratado, e o tratamento-testemunha (0% foi comparado com os demais aplicando o teste Dunnet a 5% de probabilidade. Os níveis de substituição da proteína do farelo de sojapela proteína do ovo desidratado não influenciaram as variáveis de desempenho dos animais na fase inicial, até 9%. Entretanto, avaliando a relação custo-benefício, o tratamentocontrole foi o mais rentável.This study aimed to determine the average daily weight gain, daily feed intake and the feed conversion ratio of pigs in initialphase (15 to 30 kg of weight fed with four different levels of substitution (0, 3, 6 and 9% of soybean meal protein by dehydrated egg protein. Thirty-two pigs (16 castrated males and 16 females were used in a completely randomized blocks statistical design, with fourtreatments and four repetitions each; the experimental unit was composed by a male and a female. The treatments were 0, 3, 6 and 9% of dehydrated egg protein in replacement of soybean meal protein. The data obtained were subjected to linear regression for the levels 3,6 and 9% of dehydrated egg; the witness (0% was compared with the other treatments applying Dunnett’s test at 5% probability. The replacement levels of soybean meal protein by dehydrated egg protein did not influence

  2. Procalcitonin and C-reactive protein cannot differentiate bacterial or viral infection in COPD exacerbation requiring emergency department visits

    Directory of Open Access Journals (Sweden)

    Chang CH

    2015-04-01

    Full Text Available Chih-Hao Chang,1 Kuo-Chien Tsao,2,3 Han-Chung Hu,1,4 Chung-Chi Huang,1,4 Kuo-Chin Kao,1,4 Ning-Hung Chen,1,4 Cheng-Ta Yang,1,4 Ying-Huang Tsai,4,5 Meng-Jer Hsieh4,51Department of Pulmonary and Critical Care Medicine, Linkou Chang-Gung Memorial Hospital, Chang-Gung Medical Foundation, Chang-Gung University College of Medicine, Taoyuan, Taiwan; 2Department of Laboratory Medicine, Linkou Chang-Gung Memorial Hospital, Chang-Gung Medical Foundation; 3Department of Medical Biotechnology and Laboratory Science, Chang Gung University, Taoyuan, Taiwan; 4Department of Respiratory Therapy, Chang-Gung University, Taoyuan, Taiwan; 5Department of Pulmonary and Critical Care Medicine, Chiayi Chang-Gung Memorial Hospital, Chang-Gung Medical Foundation, Puzi City, TaiwanBackground: Viral and bacterial infections are the most common causes of chronic obstructive pulmonary disease (COPD exacerbations. Whether serum inflammatory markers can differentiate bacterial from virus infection in patients with COPD exacerbation requiring emergency department (ED visits remains controversial.Methods: Viral culture and polymerase chain reaction (PCR were used to identify the viruses in the oropharynx of patients with COPD exacerbations. The bacteria were identified by the semiquantitative culture of the expectorated sputum. The peripheral blood white blood cell (WBC counts, serum C-reactive protein (CRP, procalcitonin (PCT, and clinical symptoms were compared among patients with different types of infections.Results: Viruses were isolated from 16 (22.2% of the 72 patients enrolled. The most commonly identified viruses were parainfluenza type 3, influenza A, and rhinovirus. A total of 30 (41.7% patients had positive bacterial cultures, with the most commonly found bacteria being Haemophilus influenzae and Haemophilus parainfluenzae. Five patients (6.9% had both positive sputum cultures and virus identification. The WBC, CRP, and PCT levels of the bacteria-positive and bacteria

  3. Efficiency of bacterial protein synthesis during anaerobic degradation of cattle waste.

    OpenAIRE

    Mackie, R I; Bryant, M. P.

    1990-01-01

    The rate of [15N]ammonia (15NH3) uptake or incorporation into bacterial cells was studied, using stirred, 3-liter benchtop digestors fed on a semicontinuous basis with cattle waste. The fermentations were carried out at 40 and 60 degrees C and at four different loading rates (3, 6, 9, and 12 g of volatile solids per liter of reactor volume per day). The rate of NH3-N incorporation for the period 1 to 5 h after feeding at the four different loading rates was 0.49, 0.83, 1.05, and 1.08 mg/liter...

  4. A secretory system for bacterial production of high-profile protein targets

    DEFF Research Database (Denmark)

    Kotzsch, Alexander; Vernet, Erik; Hammarström, Martin;

    2011-01-01

    Escherichia coli represents a robust, inexpensive expression host for the production of recombinant proteins. However, one major limitation is that certain protein classes do not express well in a biologically relevant form using standard expression approaches in the cytoplasm of E. coli. To impr...

  5. Production of cocktail of polyclonal antibodies using bacterial expressed recombinant protein for multiple virus detection.

    Science.gov (United States)

    Kapoor, Reetika; Mandal, Bikash; Paul, Prabir Kumar; Chigurupati, Phaneendra; Jain, Rakesh Kumar

    2014-02-01

    Cocktail of polyclonal antibodies (PAb) were produced that will help in multiple virus detection and overcome the limitation of individual virus purification, protein expression and purification as well as immunization in multiple rabbits. A dual fusion construct was developed using conserved coat protein (CP) sequences of Cucumber mosaic virus (CMV) and Papaya ringspot virus (PRSV) in an expression vector, pET-28a(+). The fusion protein (∼40kDa) was expressed in Escherichia coli and purified. Likewise, a triple fusion construct was developed by fusing conserved CP sequences of CMV and PRSV with conserved nucleocapsid protein (N) sequence of Groundnut bud necrosis virus (GBNV) and expressed as a fusion protein (∼50kDa) in pET-28a(+). PAb made separately to each of these three viruses recognized the double and triple fusion proteins in Western blot indicating retention of desired epitopes for binding with target antibodies. The fusion proteins (∼40kDa and ∼50kDa) were used to produce cocktail of PAb by immunizing rabbits, which simultaneously detected natural infection of CMV and PRSV or CMV, PRSV and GBNV in Cucurbitaceous, Solanaceous and other hosts in DAC-ELISA. This is the first report on production of a cocktail of PAb to recombinant fusion protein of two or three distinct viruses.

  6. Avoiding acidic region streaking in two-dimensional gel electrophoresis: Case study with two bacterial whole cell protein extracts

    Indian Academy of Sciences (India)

    Arnab Roy; Umesh Varshney; Debnath Pal

    2014-09-01

    Acidic region streaking (ARS) is one of the lacunae in two-dimensional gel electrophoresis (2DE) of bacterial proteome. This streaking is primarily caused by nucleic acid (NuA) contamination and poses major problem in the downstream processes like image analysis and protein identification. Although cleanup and nuclease digestion are practiced as remedial options, these strategies may incur loss in protein recovery and perform incomplete removal of NuA. As a result, ARS has remained a common observation across publications, including the recent ones. In this work, we demonstrate how ultrasound wave can be used to shear NuA in plain ice-cooled water, facilitating the elimination of ARS in the 2DE gels without the need for any additional sample cleanup tasks. In combination with a suitable buffer recipe, IEF program and frequent paper-wick changing approach, we are able to reproducibly demonstrate the production of clean 2DE gels with improved protein recovery and negligible or no ARS. We illustrate our procedure using whole cell protein extracts from two diverse organisms, Escherichia coli and Mycobacterium smegmatis. Our designed protocols are straightforward and expected to provide good 2DE gels without ARS, with comparable times and significantly lower cost.

  7. Double-Stranded RNA-Binding Protein 4 Is Required for Resistance Signaling against Viral and Bacterial Pathogens

    Directory of Open Access Journals (Sweden)

    Shifeng Zhu

    2013-09-01

    Full Text Available Plant viruses often encode suppressors of host RNA silencing machinery, which occasionally function as avirulence factors that are recognized by host resistance (R proteins. For example, the Arabidopsis R protein, hypersensitive response to TCV (HRT, recognizes the turnip crinkle virus (TCV coat protein (CP. HRT-mediated resistance requires the RNA-silencing component double-stranded RNA-binding protein 4 (DRB4 even though it neither is associated with the accumulation of TCV-specific small RNA nor requires the RNA silencing suppressor function of CP. HRT interacts with the cytosolic fraction of DRB4. Interestingly, TCV infection both increases the cytosolic DRB4 pool and inhibits the HRT-DRB4 interaction. The virulent R8A CP derivative, which induces a subset of HRT-derived responses, also disrupts this interaction. The differential localization of DRB4 in the presence of wild-type and R8A CP implies the importance of subcellular compartmentalization of DRB4. The requirement of DRB4 in resistance to bacterial infection suggests a universal role in R-mediated defense signaling.

  8. Accommodating the bacterial decoding release factor as an alien protein among the RNAs at the active site of the ribosome

    Institute of Scientific and Technical Information of China (English)

    Elizabeth S Poole; David J Young; Marjan E Askarian-Amiri; Debbie-Jane G Scarlett; Warren P Tate

    2007-01-01

    The decoding release factor (RF) triggers termination of protein synthesis by functionally mimicking a tRNA to span the decoding centre and the peptidyl transferase centre (PTC) of the ribosome. Structurally, it must fit into a site crafted for a tRNA and surrounded by five other RNAs, namely the adjacent peptidyl tRNA carrying the completed polypeptide, the mRNA and the three rRNAs. This is achieved by extending a structural domain from the body of the protein that results in a critical conformational change allowing it to contact the PTC. A structural model of the bacterial termination complex with the accommodated RF shows that it makes close contact with the first, second and third bases of the stop codon in the mRNA with two separate loops of structure: the anticodon loop and the loop at the tip of helix a5. The anticodon loop also makes contact with the base following the stop codon that is known to strongly influence termination efficiency. It confirms the close contact of domain 3 of the protein with the key RNA structures of the PTC. The mRNA signal for termination includes sequences upstream as well as downstream of the stop codon, and this may reflect structural restrictions for specific combinations of tRNA and RF to be bound onto the ribosome together. An unbiased SELEX approach has been investigated as a tool to identify potential rRNA-binding contacts of the bacterial RF in its different binding conformations within the active centre of the ribosome.

  9. Multi-location gram-positive and gram-negative bacterial protein subcellular localization using gene ontology and multi-label classifier ensemble

    Science.gov (United States)

    2015-01-01

    Background It has become a very important and full of challenge task to predict bacterial protein subcellular locations using computational methods. Although there exist a lot of prediction methods for bacterial proteins, the majority of these methods can only deal with single-location proteins. But unfortunately many multi-location proteins are located in the bacterial cells. Moreover, multi-location proteins have special biological functions capable of helping the development of new drugs. So it is necessary to develop new computational methods for accurately predicting subcellular locations of multi-location bacterial proteins. Results In this article, two efficient multi-label predictors, Gpos-ECC-mPLoc and Gneg-ECC-mPLoc, are developed to predict the subcellular locations of multi-label gram-positive and gram-negative bacterial proteins respectively. The two multi-label predictors construct the GO vectors by using the GO terms of homologous proteins of query proteins and then adopt a powerful multi-label ensemble classifier to make the final multi-label prediction. The two multi-label predictors have the following advantages: (1) they improve the prediction performance of multi-label proteins by taking the correlations among different labels into account; (2) they ensemble multiple CC classifiers and further generate better prediction results by ensemble learning; and (3) they construct the GO vectors by using the frequency of occurrences of GO terms in the typical homologous set instead of using 0/1 values. Experimental results show that Gpos-ECC-mPLoc and Gneg-ECC-mPLoc can efficiently predict the subcellular locations of multi-label gram-positive and gram-negative bacterial proteins respectively. Conclusions Gpos-ECC-mPLoc and Gneg-ECC-mPLoc can efficiently improve prediction accuracy of subcellular localization of multi-location gram-positive and gram-negative bacterial proteins respectively. The online web servers for Gpos-ECC-mPLoc and Gneg

  10. Changes in the protein fraction of Merluccius bilinearis muscle under lactic acid bacterial fermentation using a Lactobacillus Acidophilus starter culture (ESP

    Directory of Open Access Journals (Sweden)

    Luis J. Elizondo

    2016-03-01

    Full Text Available The effect of lactic acid bacterial fermentation on the protein fraction of Merluccius bilinearis muscle was evaluated. The non-protein fraction increased progressively with corresponding decreases in the percentage protein (dry weight indicating proteolytic activity during fermentation. Significant increases in the percentages of the amino acids cystine, isoleucine, phenylalanine and tyrosine were observed after two months of fermentation. Percentages of arginine decreased significantly after one week and again after two months of fermentation.

  11. A high-throughput method to examine protein-nucleotide interactions identifies targets of the bacterial transcriptional regulatory protein fur.

    Directory of Open Access Journals (Sweden)

    Chunxiao Yu

    Full Text Available The Ferric uptake regulatory protein (Fur is a transcriptional regulatory protein that functions to control gene transcription in response to iron in a number of pathogenic bacteria. In this study, we applied a label-free, quantitative and high-throughput analysis method, Interferometric Reflectance Imaging Sensor (IRIS, to rapidly characterize Fur-DNA interactions in vitro with predicted Fur binding sequences in the genome of Neisseria gonorrhoeae, the causative agent of the sexually transmitted disease gonorrhea. IRIS can easily be applied to examine multiple protein-protein, protein-nucleotide and nucleotide-nucleotide complexes simultaneously and demonstrated here that seventy percent of the predicted Fur boxes in promoter regions of iron-induced genes bound to Fur in vitro with a range of affinities as observed using this microarray screening technology. Combining binding data with mRNA expression levels in a gonococcal fur mutant strain allowed us to identify five new gonococcal genes under Fur-mediated direct regulation.

  12. Exploring structure and interactions of the bacterial adaptor protein YjbH by crosslinking mass spectrometry.

    Science.gov (United States)

    Al-Eryani, Yusra; Ib Rasmussen, Morten; Kjellström, Sven; Højrup, Peter; Emanuelsson, Cecilia; von Wachenfeldt, Claes

    2016-09-01

    Adaptor proteins assist proteases in degrading specific proteins under appropriate conditions. The adaptor protein YjbH promotes the degradation of an important global transcriptional regulator Spx, which controls the expression of hundreds of genes and operons in response to thiol-specific oxidative stress in Bacillus subtilis. Under normal growth conditions, the transcription factor is bound to the adaptor protein and therefore degraded by the AAA+ protease ClpXP. If this binding is alleviated during stress, the transcription factor accumulates and turns on genes encoding stress-alleviating proteins. The adaptor protein YjbH is thus a key player involved in these interactions but its structure is unknown. To gain insight into its structure and interactions we have used chemical crosslinking mass spectrometry. Distance constraints obtained from the crosslinked monomer were used to select and validate a structure model of YjbH and then to probe its interactions with other proteins. The core structure of YjbH is reminiscent of DsbA family proteins. One lysine residue in YjbH (K177), located in one of the α-helices outside the thioredoxin fold, crosslinked to both Spx K99 and Spx K117, thereby suggesting one side of the YjbH for the interaction with Spx. Another lysine residue that crosslinked to Spx was YjbH K5, located in the long and presumably very flexible N-terminal arm of YjbH. Our crosslinking data lend support to a model proposed based on site-directed mutagenesis where the YjbH interaction with Spx can stabilize and present the C-terminal region of Spx for protease recognition and proteolysis. Proteins 2016; 84:1234-1245. © 2016 Wiley Periodicals, Inc.

  13. Dietary supplementation with L-arginine or N-carbamylglutamate enhances intestinal growth and heat shock protein-70 expression in weanling pigs fed a corn- and soybean meal-based diet.

    Science.gov (United States)

    Wu, Xin; Ruan, Zheng; Gao, Yunling; Yin, Yulong; Zhou, Xihong; Wang, Lei; Geng, Meimei; Hou, Yongqing; Wu, Guoyao

    2010-08-01

    This study determined effects of dietary supplementation with L-arginine (Arg) or N-carbamylglutamate (NCG) on intestinal health and growth in early-weaned pigs. Eighty-four Landrace x Yorkshire pigs (average body weight of 5.56+/-0.07 kg; weaned at 21 days of age) were fed for 7 days one of the three isonitrogenous diets: (1) a corn- and soybean meal-based diet (CSM), (2) CSM+0.08% NCG (0.08%), and (3) CSM+0.6% Arg. There were four pens of pigs per diet (7 pigs/pen). At the end of a 7-day feeding period, six piglets were randomly selected from each treatment for tissue collections. Compared with the control group, Arg or NCG supplementation increased (P<0.05): (1) Arg concentrations in plasma, (2) small-intestinal growth, (3) villus height in duodenum, jejunum and ileum, (4) crypt depth in jejunum and ileum, (5) goblet cell counts in intestinal mucosae, and (6) whole-body weight gain in pigs. Real-time polymerase chain reaction and western blotting analyses revealed that both mRNA and protein levels for heat shock protein-70 (HSP70) were higher (P<0.05) in the intestinal mucosae of Arg- or NCG-supplemented pigs than in the control group. Furthermore, the incidence of diarrhea in the NCG group was 18% lower (P<0.01) than that in the control group. Collectively, these results indicate that dietary supplementation with 0.6% Arg or 0.08% NCG enhances intestinal HSP70 gene expression, intestinal growth and integrity, and the availability of dietary nutrients for whole-body weight gain in postweaning pigs fed a CSM-based diet. Thus, Arg or NCG is a functional ingredient in the weaning diet to improve nutrition, health, and growth performance of these neonates.

  14. Over-expression of rice leucine-rich repeat protein results in activation of defense response, thereby enhancing resistance to bacterial soft rot in Chinese cabbage.

    Science.gov (United States)

    Park, Young Ho; Choi, Changhyun; Park, Eun Mi; Kim, Hyo Sun; Park, Hong Jae; Bae, Shin Cheol; Ahn, Ilpyung; Kim, Min Gab; Park, Sang Ryeol; Hwang, Duk-Ju

    2012-10-01

    Pectobacterium carotovorum subsp. carotovorum causes soft rot disease in various plants, including Chinese cabbage. The simple extracellular leucine-rich repeat (eLRR) domain proteins have been implicated in disease resistance. Rice leucine-rich repeat protein (OsLRP), a rice simple eLRR domain protein, is induced by pathogens, phytohormones, and salt. To see whether OsLRP enhances disease resistance to bacterial soft rot, OsLRP was introduced into Chinese cabbage by Agrobacterium-mediated transformation. Two independent transgenic lines over-expressing OsLRP were generated and further analyzed. Transgenic lines over-expressing OsLRP showed enhanced disease resistance to bacterial soft rot compared to non-transgenic control. Bacterial growth was retarded in transgenic lines over-expressing OsLRP compared to non-transgenic controls. We propose that OsLRP confers enhanced resistance to bacterial soft rot. Monitoring expression of defense-associated genes in transgenic lines over-expressing OsLRP, two different glucanases and Brassica rapa polygalacturonase inhibiting protein 2, PDF1 were constitutively activated in transgenic lines compared to non-transgenic control. Taken together, heterologous expression of OsLRP results in the activation of defense response and enhanced resistance to bacterial soft rot.

  15. Prebiotics affect nutrient digestibility but not faecal ammonia in dogs fed increased dietary protein levels.

    Science.gov (United States)

    Hesta, M; Roosen, W; Janssens, G P J; Millet, S; De Wilde, R

    2003-12-01

    An increased protein content and less digestible protein sources in the diet can induce bad faecal odour. The present study investigated the effect of adding prebiotics to dog diets enriched with animal-derived protein sources on apparent digestibilities and faecal ammonia concentration. In three subsequent periods eight healthy beagle dogs were fed a commercial dog diet that was gradually supplemented by up to 50 % with meat and bone meal (MBM), greaves meal (GM) or poultry meal (PM) respectively. Afterwards, 3 % fructo-oligosaccharides or 3 % isomalto-oligosaccharides were substituted for 3 % of the total diet. Supplementation with animal-derived protein sources did not decrease the apparent N digestibility significantly but oligosaccharides did. On the other hand the bacterial N content (% DM) in the faeces was highest in the oligosaccharide groups followed by the protein-supplemented groups and lowest in the control groups. When the apparent N digestibility was corrected for bacterial N no significant differences were noted anymore except for the GM group where the corrected N digestibility was still lower after oligosaccharide supplementation. The amount of faecal ammonia was significantly increased by supplementing with protein or oligosaccharides in the MBM and GM groups but not in the PM group. When apparent N digestibility is interpreted, a correction for bacterial N should be taken into account, especially when prebiotics are added to the diet. Oligosaccharides did not reduce the faecal ammonia concentrations as expected.

  16. Bacterial periplasmic sialic acid-binding proteins exhibit a conserved binding site

    Energy Technology Data Exchange (ETDEWEB)

    Gangi Setty, Thanuja [Institute for Stem Cell Biology and Regenerative Medicine, NCBS Campus, GKVK Post, Bangalore, Karnataka 560 065 (India); Cho, Christine [Carver College of Medicine, University of Iowa, Iowa City, IA 52242-1109 (United States); Govindappa, Sowmya [Institute for Stem Cell Biology and Regenerative Medicine, NCBS Campus, GKVK Post, Bangalore, Karnataka 560 065 (India); Apicella, Michael A. [Carver College of Medicine, University of Iowa, Iowa City, IA 52242-1109 (United States); Ramaswamy, S., E-mail: ramas@instem.res.in [Institute for Stem Cell Biology and Regenerative Medicine, NCBS Campus, GKVK Post, Bangalore, Karnataka 560 065 (India)

    2014-07-01

    Structure–function studies of sialic acid-binding proteins from F. nucleatum, P. multocida, V. cholerae and H. influenzae reveal a conserved network of hydrogen bonds involved in conformational change on ligand binding. Sialic acids are a family of related nine-carbon sugar acids that play important roles in both eukaryotes and prokaryotes. These sialic acids are incorporated/decorated onto lipooligosaccharides as terminal sugars in multiple bacteria to evade the host immune system. Many pathogenic bacteria scavenge sialic acids from their host and use them for molecular mimicry. The first step of this process is the transport of sialic acid to the cytoplasm, which often takes place using a tripartite ATP-independent transport system consisting of a periplasmic binding protein and a membrane transporter. In this paper, the structural characterization of periplasmic binding proteins from the pathogenic bacteria Fusobacterium nucleatum, Pasteurella multocida and Vibrio cholerae and their thermodynamic characterization are reported. The binding affinities of several mutations in the Neu5Ac binding site of the Haemophilus influenzae protein are also reported. The structure and the thermodynamics of the binding of sugars suggest that all of these proteins have a very well conserved binding pocket and similar binding affinities. A significant conformational change occurs when these proteins bind the sugar. While the C1 carboxylate has been identified as the primary binding site, a second conserved hydrogen-bonding network is involved in the initiation and stabilization of the conformational states.

  17. ParB Partition Proteins: Complex Formation and Spreading at Bacterial and Plasmid Centromeres

    Directory of Open Access Journals (Sweden)

    Barbara Funnell

    2016-08-01

    Full Text Available In bacteria, active partition systems contribute to the faithful segregation of both chromosomes and low-copy-number plasmids. Each system depends on a site-specific DNA binding protein to recognize and assemble a partition complex at a centromere-like site, commonly called parS. Many plasmid and all chromosomal centromere-binding proteins are dimeric helix-turn-helix DNA binding proteins, which are commonly named ParB. Although the overall sequence conservation among ParBs is not high, the proteins share similar domain and functional organization, and they assemble into similar higher-order complexes. In vivo, ParBs spread; that is, DNA binding extends away from the parS site into the surrounding nonspecific DNA, a feature that reflects higher-order complex assembly. ParBs bridge and pair DNA at parS and nonspecific DNA sites. ParB dimers interact with each other via flexible conformations of an N-terminal region. This review will focus on the properties of the HTH centromere-binding protein, in light of recent experimental evidence and models that are adding to our understanding of how these proteins assemble into large and dynamic partition complexes at and around their specific DNA sites.

  18. Phagocytosis escape by a Staphylococcus aureus protein that connects complement and coagulation proteins at the bacterial surface.

    Science.gov (United States)

    Ko, Ya-Ping; Kuipers, Annemarie; Freitag, Claudia M; Jongerius, Ilse; Medina, Eva; van Rooijen, Willemien J; Spaan, András N; van Kessel, Kok P M; Höök, Magnus; Rooijakkers, Suzan H M

    2013-01-01

    Upon contact with human plasma, bacteria are rapidly recognized by the complement system that labels their surface for uptake and clearance by phagocytic cells. Staphylococcus aureus secretes the 16 kD Extracellular fibrinogen binding protein (Efb) that binds two different plasma proteins using separate domains: the Efb N-terminus binds to fibrinogen, while the C-terminus binds complement C3. In this study, we show that Efb blocks phagocytosis of S. aureus by human neutrophils. In vitro, we demonstrate that Efb blocks phagocytosis in plasma and in human whole blood. Using a mouse peritonitis model we show that Efb effectively blocks phagocytosis in vivo, either as a purified protein or when produced endogenously by S. aureus. Mutational analysis revealed that Efb requires both its fibrinogen and complement binding residues for phagocytic escape. Using confocal and transmission electron microscopy we show that Efb attracts fibrinogen to the surface of complement-labeled S. aureus generating a 'capsule'-like shield. This thick layer of fibrinogen shields both surface-bound C3b and antibodies from recognition by phagocytic receptors. This information is critical for future vaccination attempts, since opsonizing antibodies may not function in the presence of Efb. Altogether we discover that Efb from S. aureus uniquely escapes phagocytosis by forming a bridge between a complement and coagulation protein.

  19. Location of glycine mutations within a bacterial collagen protein affects degree of disruption of triple-helix folding and conformation.

    Science.gov (United States)

    Cheng, Haiming; Rashid, Shayan; Yu, Zhuoxin; Yoshizumi, Ayumi; Hwang, Eileen; Brodsky, Barbara

    2011-01-21

    The hereditary bone disorder osteogenesis imperfecta is often caused by missense mutations in type I collagen that change one Gly residue to a larger residue and that break the typical (Gly-Xaa-Yaa)(n) sequence pattern. Site-directed mutagenesis in a recombinant bacterial collagen system was used to explore the effects of the Gly mutation position and of the identity of the residue replacing Gly in a homogeneous collagen molecular population. Homotrimeric bacterial collagen proteins with a Gly-to-Arg or Gly-to-Ser replacement formed stable triple-helix molecules with a reproducible 2 °C decrease in stability. All Gly replacements led to a significant delay in triple-helix folding, but a more dramatic delay was observed when the mutation was located near the N terminus of the triple-helix domain. This highly disruptive mutation, close to the globular N-terminal trimerization domain where folding is initiated, is likely to interfere with triple-helix nucleation. A positional effect of mutations was also suggested by trypsin sensitivity for a Gly-to-Arg replacement close to the triple-helix N terminus but not for the same replacement near the center of the molecule. The significant impact of the location of a mutation on triple-helix folding and conformation could relate to the severe consequences of mutations located near the C terminus of type I and type III collagens, where trimerization occurs and triple-helix folding is initiated.

  20. 2D and 3D crystallization of a bacterial homologue of human vitamin C membrane transport proteins.

    Science.gov (United States)

    Jeckelmann, Jean-Marc; Harder, Daniel; Ucurum, Zöhre; Fotiadis, Dimitrios

    2014-10-01

    Most organisms are able to synthesize vitamin C whereas humans are not. In order to contribute to the elucidation of the molecular working mechanism of vitamin C transport through biological membranes, we cloned, overexpressed, purified, functionally characterized, and 2D- and 3D-crystallized a bacterial protein (UraDp) with 29% of amino acid sequence identity to the human sodium-dependent vitamin C transporter 1 (SVCT1). Ligand-binding experiments by scintillation proximity assay revealed that uracil is a substrate preferably bound to UraDp. For structural analysis, we report on the production of tubular 2D crystals and present a first projection structure of UraDp from negatively stained tubes. On the other hand the successful growth of UraDp 3D crystals and their crystallographic analysis is described. These 3D crystals, which diffract X-rays to 4.2Å resolution, pave the way towards the high-resolution crystal structure of a bacterial homologue with high amino acid sequence identity to human SVCT1.

  1. Reducing the toxicity of castor seed meal through processing treatments

    Science.gov (United States)

    The castor plant produces a seed that is high in oil content and composed of approximately 90% ricinoleate. Due to the numerous uses of castor oil and ricinoleate, the oil is in high demand. However, the presence of a protein toxin in the seed meal is a key concern about processing the castor seed t...

  2. Concentration of Key Elements in North American Meat & Bone Meal

    Science.gov (United States)

    Meat & bone meal (MBM) and related rendered protein commodities have potential for use in applications other than animal feed, including use as a fuel or a phosphorus fertilizer. In order to develop these applications, data on the elemental composition are required; the currently available elementa...

  3. Monitoring Dynamic Protein Expression in Single Living E. Coli. Bacterial Cells by Laser Tweezers Raman Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Chan, J W; Winhold, H; Corzett, M H; Ulloa, J M; Cosman, M; Balhorn, R; Huser, T

    2007-01-09

    Laser tweezers Raman spectroscopy (LTRS) is a novel, nondestructive, and label-free method that can be used to quantitatively measure changes in cellular activity in single living cells. Here, we demonstrate its use to monitor changes in a population of E. coli cells that occur during overexpression of a protein, the extracellular domain of myelin oligodendrocyte glycoprotein (MOG(1-120)) Raman spectra were acquired of individual E. coli cells suspended in solution and trapped by a single tightly focused laser beam. Overexpression of MOG(1-120) in transformed E. coli Rosetta-Gami (DE3)pLysS cells was induced by addition of isopropyl thiogalactoside (IPTG). Changes in the peak intensities of the Raman spectra from a population of cells were monitored and analyzed over a total duration of three hours. Data was also collected for concentrated purified MOG(1-120) protein in solution, and the spectra compared with that obtained for the MOG(1-120) expressing cells. Raman spectra of individual, living E. coli cells exhibit signatures due to DNA and protein molecular vibrations. Characteristic Raman markers associated with protein vibrations, such as 1257 cm{sup -1}, 1340 cm{sup -1}, 1453 cm{sup -1} and 1660 cm{sup -1}, are shown to increase as a function of time following the addition of IPTG. Comparison of these spectra and the spectra of purified MOG protein indicates that the changes are predominantly due to the induction of MOG protein expression. Protein expression was found to occur mostly within the second hour, with a 470% increase relative to the protein expressed in the first hour. A 230% relative increase between the second and third hour indicates that protein expression begins to level off within the third hour. It is demonstrated that LTRS has sufficient sensitivity for real-time, nondestructive, and quantitative monitoring of biological processes, such as protein expression, in single living cells. Such capabilities, which are not currently available in

  4. PROTEIN QUALITY CONTROL IN BACTERIAL CELLS: INTEGRATED NETWORKS OF CHAPERONES AND ATP-DEPENDENT PROTEASES.

    Energy Technology Data Exchange (ETDEWEB)

    FLANAGAN,J.M.; BEWLEY,M.C.

    2001-12-03

    It is generally accepted that the information necessary to specify the native, functional, three-dimensional structure of a protein is encoded entirely within its amino acid sequence; however, efficient reversible folding and unfolding is observed only with a subset of small single-domain proteins. Refolding experiments often lead to the formation of kinetically-trapped, misfolded species that aggregate, even in dilute solution. In the cellular environment, the barriers to efficient protein folding and maintenance of native structure are even larger due to the nature of this process. First, nascent polypeptides must fold in an extremely crowded environment where the concentration of macromolecules approaches 300-400 mg/mL and on average, each ribosome is within its own diameter of another ribosome (1-3). These conditions of severe molecular crowding, coupled with high concentrations of nascent polypeptide chains, favor nonspecific aggregation over productive folding (3). Second, folding of newly-translated polypeptides occurs in the context of their vehtorial synthesis process. Amino acids are added to a growing nascent chain at the rate of -5 residues per set, which means that for a 300 residue protein its N-terminus will be exposed to the cytosol {approx}1 min before its C-terminus and be free to begin the folding process. However, because protein folding is highly cooperative, the nascent polypeptide cannot reach its native state until a complete folding domain (50-250 residues) has emerged from the ribosome. Thus, for a single-domain protein, the final steps in folding are only completed post-translationally since {approx}40 residues of a nascent chain are sequestered within the exit channel of the ribosome and are not available for folding (4). A direct consequence of this limitation in cellular folding is that during translation incomplete domains will exist in partially-folded states that tend to expose hydrophobic residues that are prone to aggregation and

  5. PROTEIN QUALITY CONTROL IN BACTERIAL CELLS: INTEGRATED NETWORKS OF CHAPERONES AND ATP-DEPENDENT PROTEASES.

    Energy Technology Data Exchange (ETDEWEB)

    FLANAGAN,J.M.BEWLEY,M.C.

    2002-10-01

    It is generally accepted that the information necessary to specify the native, functional, three-dimensional structure of a protein is encoded entirely within its amino acid sequence; however, efficient reversible folding and unfolding is observed only with a subset of small single-domain proteins. Refolding experiments often lead to the formation of kinetically-trapped, misfolded species that aggregate, even in dilute solution. In the cellular environment, the barriers to efficient protein folding and maintenance of native structure are even larger due to the nature of this process. First, nascent polypeptides must fold in an extremely crowded environment where the concentration of macromolecules approaches 300-400 mg/mL and on average, each ribosome is within its own diameter of another ribosome (1-3). These conditions of severe molecular crowding, coupled with high concentrations of nascent polypeptide chains, favor nonspecific aggregation over productive folding (3). Second, folding of newly-translated polypeptides occurs in the context of their vehtorial synthesis process. Amino acids are added to a growing nascent chain at the rate of {approx}5 residues per set, which means that for a 300 residue protein its N-terminus will be exposed to the cytosol {approx}1 min before its C-terminus and be free to begin the folding process. However, because protein folding is highly cooperative, the nascent polypeptide cannot reach its native state until a complete folding domain (50-250 residues) has emerged from the ribosome. Thus, for a single-domain protein, the final steps in ffolding are only completed post-translationally since {approx}40 residues of a nascent chain are sequestered within the exit channel of the ribosome and are not available for folding (4). A direct consequence of this limitation in cellular folding is that during translation incomplete domains will exist in partially-folded states that tend to expose hydrophobic residues that are prone to

  6. Effects of prior acute exercise on circulating cytokine concentration responses to a high-fat meal.

    Science.gov (United States)

    Brandauer, Josef; Landers-Ramos, Rian Q; Jenkins, Nathan T; Spangenburg, Espen E; Hagberg, James M; Prior, Steven J

    2013-08-01

    High-fat meal consumption alters the circulating cytokine profile and contributes to cardiometabolic diseases. A prior bout of exercise can ameliorate the triglyceride response to a high-fat meal, but the interactive effects of exercise and high-fat meals on cytokines that mediate cardiometabolic risk are not fully understood. We investigated the effects of prior exercise on the responses of circulating tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), IL-8, leptin, retinol-binding protein 4 (RBP4), vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), placental growth factor (PlGF), and soluble fms-like tyrosine kinase-1 (sFlt-1) to a high-fat meal. Ten healthy men were studied before and 4 h after ingestion of a high-fat meal either with or without ∼50 min of endurance exercise at 70% of VO2 max on the preceding day. In response to the high-fat meal, lower leptin and higher VEGF, bFGF, IL-6, and IL-8 concentrations were evident (P exercise (P exercise and the high-fat meal on sFlt-1 (P exercise and 218% with prior exercise (P exercise does not affect all high-fat meal-induced changes in circulating cytokines, but does affect fasting or postprandial concentrations of IL-6, leptin, and sFlt-1. These data may reflect a salutary effect of prior exercise on metabolic responses to a high-fat meal.

  7. Prevalence and Characterization of Salmonella in Animal Meals Collected from Rendering Operations.

    Science.gov (United States)

    Jiang, Xiuping

    2016-06-01

    As part of the Salmonella Education Reduction Program, the Animal Protein Producers Industry initiated a yearlong microbiological survey of animal meals from 1 January to 31 December 2010. The types of animal meals included poultry meal, pork and beef crax, meat meal, meat and bone meal, feather meal, blood meal, and fish meal from a variety of rendering operations (n = 65). Salmonella was positive in 731 (8.3%) of 8,783 analyzed samples, with contamination rates as 1.0, 33.2, and 21.3% from samples collected right after press, being loaded out, or unidentified, respectively. The randomly selected positive Salmonella samples (n = 100) representing 1.1% of the total samples tested were enumerated by the most-probable-number (MPN) method. The Salmonella contamination level ranged from meals declined compared with previous surveys, and none of the Salmonella serotypes concerning target animal health were isolated. In addition, most Salmonella isolates remained susceptible to the majority of the 15 most commonly used antibiotics.

  8. Rational design of ultrastable and reversibly photoswitchable fluorescent proteins for super-resolution imaging of the bacterial periplasm

    Science.gov (United States)

    El Khatib, Mariam; Martins, Alexandre; Bourgeois, Dominique; Colletier, Jacques-Philippe; Adam, Virgile

    2016-01-01

    Phototransformable fluorescent proteins are central to several nanoscopy approaches. As yet however, there is no available variant allowing super-resolution imaging in cell compartments that maintain oxidative conditions. Here, we report the rational design of two reversibly switchable fluorescent proteins able to fold and photoswitch in the bacterial periplasm, rsFolder and rsFolder2. rsFolder was designed by hybridisation of Superfolder-GFP with rsEGFP2, and inherited the fast folding properties of the former together with the rapid switching of the latter, but at the cost of a reduced switching contrast. Structural characterisation of the switching mechanisms of rsFolder and rsEGFP2 revealed different scenarios for chromophore cis-trans isomerisation and allowed designing rsFolder2, a variant of rsFolder that exhibits improved switching contrast and is amenable to RESOLFT nanoscopy. The rsFolders can be efficiently expressed in the E. coli periplasm, opening the door to the nanoscale investigation of proteins localised in hitherto non-observable cellular compartments. PMID:26732634

  9. Efficacy of coating activated carbon with milk proteins to prevent binding of bacterial cells from foods for PCR detection.

    Science.gov (United States)

    Opet, Nathan J; Levin, Robert E

    2013-08-01

    Foods contaminated with pathogens are common sources of illness. Currently, the most common and sensitive rapid detection method involves the PCR. However, food matrices are complex and contain inhibitors that limit the sensitivity of the PCR. The use of coated activated carbon can effectively facilitate the removal of PCR inhibitors without binding targeted bacterial cells from food samples. With the use of activated carbon coated with milk proteins, a cell recovery at pH 7.0 of 95.7%±2.0% was obtained, compared to control uncoated activated carbon, which yielded a cell recovery of only 1.1%±0.8%. In addition, the milk protein coated activated carbon was able to absorb similar amounts of soluble compounds as uncoated activated carbon, with the exception of bovine hemoglobin. This suggests that the use of milk proteins to coat activated carbon may therefore serve as a suitable replacement for bentonite in the coating of activated carbon, which has previously been used for the removal of PCR inhibitors from food.

  10. How covalent heme to protein bonds influence the formation and reactivity of redox intermediates of a bacterial peroxidase.

    Science.gov (United States)

    Auer, Markus; Nicolussi, Andrea; Schütz, Georg; Furtmüller, Paul G; Obinger, Christian

    2014-11-07

    The most striking feature of mammalian peroxidases, including myeloperoxidase and lactoperoxidase (LPO) is the existence of covalent bonds between the prosthetic group and the protein, which has a strong impact on their (electronic) structure and biophysical and chemical properties. Recently, a novel bacterial heme peroxidase with high structural and functional similarities to LPO was described. Being released from Escherichia coli, it contains mainly heme b, which can be autocatalytically modified and covalently bound to the protein by incubation with hydrogen peroxide. In the present study, we investigated the reactivity of these two forms in their ferric, compound I and compound II state in a multi-mixing stopped-flow study. Upon heme modification, the reactions between the ferric proteins with cyanide or H2O2 were accelerated. Moreover, apparent bimolecular rate constants of the reaction of compound I with iodide, thiocyanate, bromide, and tyrosine increased significantly and became similar to LPO. Kinetic data are discussed and compared with known structure-function relationships of the mammalian peroxidases LPO and myeloperoxidase.

  11. Functional roles of the pre-sensor I insertion sequence in an AAA+ bacterial enhancer binding protein.