Herpes simplex virus type 1 virion‐derived US11 inhibits type 1 interferon‐induced protein kinase R phosphorylation

The herpes simplex virus type 1 (HSV‐1) VRTK^? strain that was previously isolated in our laboratory as an acyclovir‐resistant thymidine kinase (TK)‐deficient mutant, is more sensitive to type 1 interferon than is the parent strain VR3. The properties of this mutant were investigated to clarify the mechanism for its hyper‐sensitivity to interferon (IFN). It was found that: (i) IFN‐pretreated cells, but not those treated with IFN after adsorption, are hyper‐sensitive to IFN; (ii) the mutant cannot inhibit protein kinase R phosphorylation efficiently during the early stage of replication (2 hrs post‐infection); (iii) expression of US11 in infected cells and its incorporation into the virion is reduced in the mutant compared to the wild type, despite the fact that a similar degree of DNA synthesis occurs during replication of both strains and; (iv) over‐expression of wild‐type viral TK has no effect on the phenotype of the VRTK^? strain, indicating that the phenotype is induced by a mutation(s) that does not involve the TK gene. These results suggested that the presence of US11 in the virion, but not that expressed after infection, plays an important role in the escape function of HSV‐1 from the antiviral activity of type 1 IFN.

     

Role of Swelling Pressure on the Distribution Coefficient of Maltooligosaccharide in a Cation-exchange Resin

The distribution coefficients of maltooligosaccharides with a degree of polymerization of 1 to 7 in cation-exchange resins (Amberlites HFS-471X and CG-60) with various crosslinkages and of counterion forms were used to estimate the swelling pressure of the resins. The distribution coefficient of glucose in the resin with 6 % divinylbenzene of various ionic forms was measured by varying the ionic strength of the eluent. Although the resins shrank with increasing ionic strength, the distribution coefficient became larger. These results suggest that the swelling pressure of an ion-exchange resin plays an important role in the distribution of a non-electrolyte such as maltooligosaccharide to the resin. A simple method to estimate the swelling pressure is also described.     

Studies on the Cereal Starches

Twenty purified rice starches of domestic and imported rices from eight countries including indica and japonica subspecies were submitted to the test of the chemical compositions, pasting characteristics and dynamic visco-elasticity of cold paste body. High correlations were found between some of these characteristics in which were observed obvious differences among the samples. For characterization of rice starches, the samples were classified in 4 groups, according to the degree of these starch characters, which were roughly expressed as “Sticky type” and “Non-sticky or Flaky type”     

Enzymatic Racemization of Leucine and α-Aminobutyrate

The distribution of amino acid racemase activities was investigated in the cell-free extracts of various strains of bacteria. Alanine racemase activity was exclusively found in all the strains tested. However, the cell-free extract of Strain 25-3, which has been identified as Pseudomonas striata, possessed the high activity catalyzing the racemization of alanine, α-aminobutyrate, leucine and methionine. The new and sensitive assay method of amino acid racemase with d-amino acid oxidase and 3-methyl-2-benzothiazolone hydrazone hydrochloride was established.

A new amino acid racemase catalyzing the conversion of either d or l enantiomorph of leucine and α-aminobutyrate to the racemates, was partially purified from the cell-free extract of Pseudomonas striata. Both the racemase reactions are suggested to be catalyzed by a single enzyme because of the constant ratio between the activities during the purification, and of their very resemble behavior to pH, temperature and heating the enzyme. Pyridoxal phosphate functions as the coenzyme for this racemase.     

Studies on Amino Acid Contents of Processed Soybean

Effect of heating on the nutritive value of defatted soybean flour has been investigated by animal experiments. Loss due to heat degradation was evaluated in two ways. In the first method, the amino acids lost during overheating were supplemented by cystine and mixture of lysine, arginine, tryptophan, and serine at dietary levels of 1.6% nitrogen, and cystine and mixture of those amino acids plus histidine at dietary levels of 3.2% nitrogen. The other procedure adopted was the absorbent test used with amino acid mixtures based on the pattern of amino acids released by pancreatic hydrolysis of unheated, properly heated, and overheated defatted soybean flour at 6 and 120 hr hydrolysis.

At 1.6% dietary nitrogen level, the nutritive value of overheated soybean flour increased by supplementation with cystine and amino acid mixture, but at the 3.2% nitrogen level only cystine was effective. Supplementation of lost amino acids to overheated flour did not restore the nutritive value to that of the properly heated flour. Based on the amino acids released by pancreatic hydrolysis of unheated, properly heated, and overheated soybean flour after 6 and 120 hr reaction, amino acid mixtures were prepared and tested for their nutritive value. While the nutritive value of amino acid mixture prepared based on the pattern of amino acid liberated by 6 hr digestion of unheated, properly heated, and overheated flour did not show similar trend to that of 3 kinds of flour itself, the nutritive value of the amino acid mixture prepared after the data obtained by 120 hr digestion agreed well with the trend of unheated or heated soybean flour.

The nutritive value was also measured by the nitrogen balance of test animals.     

CENP‐T provides a structural platform for outer kinetochore assembly

The kinetochore forms a dynamic interface with microtubules from the mitotic spindle during mitosis. The Ndc80 complex acts as the key microtubule‐binding complex at kinetochores. However, it is unclear how the Ndc80 complex associates with the inner kinetochore proteins that assemble upon centromeric chromatin. Here, based on a high‐resolution structural analysis, we demonstrate that the N‐terminal region of vertebrate CENP‐T interacts with the ‘RWD' domain in the Spc24/25 portion of the Ndc80 complex. Phosphorylation of CENP‐T strengthens a cryptic hydrophobic interaction between CENP‐T and Spc25 resulting in a phospho‐regulated interaction that occurs without direct recognition of the phosphorylated residue. The Ndc80 complex interacts with both CENP‐T and the Mis12 complex, but we find that these interactions are mutually exclusive, supporting a model in which two distinct pathways target the Ndc80 complex to kinetochores. Our results provide a model for how the multiple protein complexes at kinetochores associate in a phospho‐regulated manner.     

Fluorite Dissolution by a Phosphate-Solubilizing Bacterium Isolated from Groundwater of Xianghuangqi County,Inner Mongolia,China

Abstract

Xianghuangqi County of Inner Mongolia is a typical high-fluoride area in China. Present work discussed a possible role of phosphate-solubilizing bacteria (PSBs) in the formation of high-fluoride groundwater in this area. An indigenous PSB was isolated from the local groundwater. Analysis of 16S rDNA sequence indicates that the bacterium belongs to the Pseudomonas genus. This bacterium caused acidification of the culture media under phosphate-limited conditions. HPLC analysis detected several metabolites that are likely to acidify the cultural media. Fluorite dissolution experiment with this bacterium in minimum medium containing 2?mg/L, 20?mg/L, and 200?mg/L glucose showed that the initial concentration of glucose has a large effect on pH of the culture medium and the fluorite dissolution rate. The pH of bacterial cell-free medium remained constant throughout the experiment. Introduction of the PSB caused an initial decrease in pH, followed by an increase. The measured pH minima were 4.8, 5.8, and 6.0 for culture media amended with 200?mg/L, 20?mg/L, and 2?mg/L glucose, respectively. A slow increase of the fluoride concentration in bacterial cell-free medium was observed, and inoculation of the PSB increased the rate of fluoride release causing the concentration of fluoride in bacterial-inoculated medium to markedly exceed that found in control medium. The highest fluorite dissolution rate was observed in culture medium amended with 200?mg/L glucose, while the rates observed in culture medium amended with 20?mg/L and 2?mg/L glucose were comparable. Given the ubiquity of PSBs in natural environment, these findings show PSBs could be important contributors to fluoride mobilization in high fluoride area.     

Microbial monomers custom-synthesized to build true bio-derived aromatic polymers

Aromatic polymers include novel and extant functional materials although none has been produced from biotic building blocks derived from primary biomass glucose. Here we screened microbial aromatic metabolites, engineered bacterial metabolism and fermented the aromatic lactic acid derivative β-phenyllactic acid (PhLA). We expressed the Wickerhamia fluorescens gene (pprA) encoding a phenylpyruvate reductase in Escherichia coli strains producing high levels of phenylalanine, and fermented optically pure (>99.9 %) D-PhLA. Replacing pprA with bacterial ldhA encoding lactate dehydrogenase generated L-PhLA, indicating that the produced enzymes converted phenylpyruvate, which is an intermediate of phenylalanine synthesis, to these chiral PhLAs. Glucose was converted under optimized fermentation conditions to yield 29 g/l d-PhLA, which was purified from fermentation broth. The product satisfied the laboratory-scale chemical synthesis of poly(d-PhLA) with M _w 28,000 and allowed initial physiochemical characterization. Poly(d-PhLA) absorbed near ultraviolet light, and has the same potential as all other biomass-derived aromatic bioplastics of phenylated derivatives of poly(lactic acid). This approach to screening and fermenting aromatic monomers from glucose exploits a new era of bio-based aromatic polymer design and will contribute to petroleum conservation and carbon dioxide fixation.     

Quantitative Trait Loci (QTL) Associated with Resistance to a Monogenean Parasite (Benedenia seriolae) in Yellowtail (Seriola quinqueradiata) through Genome Wide Analysis

Benedenia infections caused by the monogenean fluke ectoparasite Benedenia seriolae seriously impact marine finfish aquaculture. Genetic variation has been inferred to play a significant role in determining the susceptibility to this parasitic disease. To evaluate the genetic basis of Benedenia disease resistance in yellowtail (Seriola quinqueradiata), a genome-wide and chromosome-wide linkage analyses were initiated using F₁ yellowtail families (n = 90 per family) based on a high-density linkage map with 860 microsatellite and 142 single nucleotide polymorphism (SNP) markers. Two major quantitative trait loci (QTL) regions on linkage groups Squ2 (BDR-1) and Squ20 (BDR-2) were identified. These QTL regions explained 32.9–35.5% of the phenotypic variance. On the other hand, we investigated the relationship between QTL for susceptibility to B. seriolae and QTL for fish body size. The QTL related to growth was found on another linkage group (Squ7). As a result, this is the first genetic evidence that contributes to detailing phenotypic resistance to Benedenia disease, and the results will help resolve the mechanism of resistance to this important parasitic infection of yellowtail.