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81.
FREE CHOICE PROFILING OF CHILEAN GOAT CHEESE   总被引:1,自引:0,他引:1  
Different goat cheeses from Chile were studied by Free-Choice Profile (FCP) analysis. Generalized Procrustes Analysis (GPA) applied to FCP data permitted differentiation between samples and informed on the attributes responsible for the observed differences. Appearance was a dominant factor in discriminating samples and to a lesser degree textural variables were also correlated with GPA dimensions. In acceptability the fresh cheeses were significantly preferred over the ripened ones.  相似文献   
82.

Background  

There are four widely used experimental strains of N. gonorrhoeae, one of which has been sequenced and used as the basis for the construction of a multi-strain, mutli-species pan-neisserial microarray. Although the N. gonorrhoeae population structure is thought to be less diverse than N. meningitidis, there are some recognized gene-complement differences between strains, including the 59 genes of the Gonococcal Genetic Island. In this study we have investigated the three experimental strains that have not been sequenced to determine the extent and nature of their similarities and differences.  相似文献   
83.
In the article the short information about A.V. Palladin Memorial Museum, displaying some documentary materials on the life, scientific, scientific-administrative and enlightenment activity of the founder of the Institute of Biochemistry and Ukrainian Biochemical school, President of UkSSR Academy of Sciences (1946-1962), outstanding scientist and public figure, Academician Alexander Vladimirovich Palladin (1885-1972). The Museum created according to the Resolution of the UkSSR Soviet of Ministers due to the efforts of the Institute personnel, is officially considered as an affiliate of the State Historical Museum of Kiev and acquired a wide-spread reputation as a center of propagation and study of the history of Ukraine biochemical science, its achievements, contribution of the native scientists into the world treasury of the life sciences.  相似文献   
84.
Nitric oxide (NO) reacts with superoxide anion to form the peroxynitrite anion (ONOO-), a molecule with pulmonary vasodilator properties in the adult rat. The purpose of this study was to compare the effects of ONOO- on intrapulmonary arteries from the newborn (days 4-7), juvenile (day 14), and adult rat. Following thromboxane A2 (TXA2) analogue (U46619) prestimulation, newborn vessels were more sensitive to ONOO- -induced muscle contraction, compared to both the juvenile and the adult vessels. Peroxynitrite-induced contraction in newborn vessels was abrogated by ibuprofen, an endothelin B-receptor blocker (A-192621), or a rho-kinase-specific inhibitor (Y27632) (all p < 0.01). Following KCl stimulation and TXA2 receptor blockade, ONOO- induced NO-dependent muscle relaxation in newborn vessels via stimulation of the endothelial and inducible nitric oxide synthases. However, in the presence of ONOO-, the pulmonary artery relaxation response to endothelium-dependent stimulation was significantly reduced (p < 0.01). Finally, newborn but not adult pulmonary arteries exposed to ONOO- showed a 10-fold increase in 8-isoprostane production, a possible mediator of ONOO- -induced contraction. We conclude that exposure to ONOO- results in a unique response in newborn intrapulmonary arteries characterized by increased 8-isoprostane generation, which we believe is responsible for its vasoconstrictor effect. This unique response potentially renders the newborn more susceptible to ONOO- -induced pulmonary hypertension than older animals.  相似文献   
85.
86.
文章对相同条件下培养的莱茵衣藻野生型CC-137和八氢番茄红素脱氢酶(phytoene desaturase,PDS)基因突变株Nfr-4的生长进行分析;并用反相高效液相色谱分析总有色类胡萝卜素以及叶绿素含量变化,结果表明两者生长的差异明显;Nfr-4突变株的单细胞叶绿素和总有色类胡萝卜素含量高于野生型CC-137的。  相似文献   
87.
Anoxic conditions should hamper the transport of sugar in the phloem, as this is an active process. The canopy is a carbohydrate source and the roots are carbohydrate sinks. By fumigating the shoot with N2 or flooding the rhizosphere, anoxic conditions in the source or sink, respectively, were induced. Volume flow, velocity, conducting area and stationary water of the phloem were assessed by non‐invasive magnetic resonance imaging (MRI) flowmetry. Carbohydrates and δ13C in leaves, roots and phloem saps were determined. Following flooding, volume flow and conducting area of the phloem declined and sugar concentrations in leaves and in phloem saps slightly increased. Oligosaccharides appeared in phloem saps and after 3 d, carbon transport was reduced to 77%. Additionally, the xylem flow declined and showed finally no daily rhythm. Anoxia of the shoot resulted within minutes in a reduction of volume flow, conductive area and sucrose in the phloem sap decreased. Sugar transport dropped to below 40% by the end of the N2 treatment. However, volume flow and phloem sap sugar tended to recover during the N2 treatment. Both anoxia treatments hampered sugar transport. The flow velocity remained about constant, although phloem sap sugar concentration changed during treatments. Apparently, stored starch was remobilized under anoxia.  相似文献   
88.

Background  

Genetic code alterations have been reported in mitochondrial, prokaryotic, and eukaryotic cytoplasmic translation systems, but their evolution and how organisms cope and survive such dramatic genetic events are not understood.  相似文献   
89.
A specific endo-1,3-β-d-glucanase (GFA) gene was found in genome of marine bacterium Formosa algae KMM 3553. For today this is the only characterized endo-1,3-β-d-glucanase (EC 3.2.1.39) in Formosa genus and the only bacterial EC 3.2.1.39 GH16 endo-1,3-β-d-glucanase with described transglycosylation activity. It was expressed in E. coli and isolated in homogeneous state. Investigating the products of polysaccharides digestion with GFA allowed to establish it’s substrate specificity and classify this enzyme as glucan endo-1,3-β-d-glucosidase (EC 3.2.1.39). The amino-acid sequence of GFA consists of 556 residues and shows sequence similarity of 45–85% to β-1,3-glucanases of bacteria belonging to the CAZy 16th structural family of glycoside hydrolases GH16. Enzyme has molecular weight 61 kDa, exhibits maximum of catalytic activity at 45?°C, pH 5.5. Half-life period at 45 °С is 20 min, complete inactivation happens at 55?°C within 10 min. Km for hydrolysis of laminarin is 0.388 mM. GFA glucanase from marine bacteria F. algae is one of rare enzymes capable to catalyze reactions of transglycosylation. It catalyzed transfer of glyconic part of substrate molecule on methyl-β-d-xylopyranoside, glycerol and methyl-α-d-glucopyranoside. The enzyme can be used in structure determination of β-1,3-glucans (or mixed 1,3;1,4- and 1,3;1,6-β-d-glucans) and enzymatic synthesis of new carbohydrate-containing compounds.  相似文献   
90.
Bacteria are able “to sense” an increase in the cell population density and to respond to it by the induction of special sets of genes. This type of regulation, called Quorum Sensing (QS), includes the production and excretion of low-molecular-weight signaling molecules (autoinducers, AI), which diffuse readily through the cell wall, from cells into the medium. As the bacterial population reaches the critical level of density, the concentration of these signaling molecules in the medium increases as a function of population density. On reaching the critical threshold concentration, AIs bind to specific receptor regulatory proteins, which induce the expression of target genes. By means of AIs, bacteria accomplish the communication that is the transmission of information between bacteria belonging to the same or different species, genera, and even families: the signaling molecules of some bacteria affect the receptors of others causing a coordinated reply of cells of the bacterial population. Bacteria of different taxonomic groups use the QS systems in regulation of a broad range of physiological activities. These processes include virulence, symbiosis, conjugation, biofilm formation, bioluminescence, synthesis of enzymes, antibiotic substances, etc. Here we review different QS systems of bacteria, the role of QS in bacterial communication, and some applied aspects of QS regulation application.  相似文献   
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