Biological characteristics ofCryptosporiopsis abietina on Hinoki cypress and its antagonistic effect to other microorganisms

In isolation tests on different parts of sound Hinoki cypress (Chamaecyparis obtusa), the coelomyceteCryptosporiopsis abietina was isolated, mostly from immature cone scales and inner bark areas of branches and main stems. In isolation tests using branches or stems of 3-yr-old seedlings to 35-yr-old adult cypresses from various localities,C. abietina was isolated in 28 to 100% of the cypresses tested. It was also confirmed that the fungus rarely infects seeds of the cypress, and can survive in dried seeds for several years, though it is not a seed-borne fungus. No symptoms appeared in inoculation tests with the fungus on 8-yr-old cypress. In inoculation test in a greenhouse, reliable infection without symptoms was obtained on wounded cypress seedlings. These results reveal thatC. abietina is a common endophytic fungus in Hinoki cypress. Confrontation and volatile antagonistic tests in Petri dishes indicated that some isolates ofC. abietina produce antifungal substances in vitro. On these isolates, the reproduction of a mycophagous nematodeBursaphelenchus xylophilus was retarded. The results of inoculation tests suggest that the possibility ofC. abietina as a primary causal agent of the resinous stem canker of Hinoki cypress is low. The role ofC. abietina in the cypress is briefly discussed.     

Glutathione production by efficient ATP-regenerating Escherichia coli mutants

There is an ongoing demand to improve the ATP-regenerating system for industrial ATP-driven bioprocesses because of the low efficiency of ATP regeneration. To address this issue, we investigated the efficiency of ATP regeneration in Escherichia coli using the Permeable Cell Assay. This assay identified 40 single-gene deletion strains that had over 150% higher total cellular ATP synthetic activity relative to the parental strain. Most of them also showed higher ATP-driven glutathione synthesis. The deleted genes of the identified strains that showed increased efficiency of ATP regeneration for glutathione production could be divided into the following four groups: (1) glycolytic pathway-related genes, (2) genes related to degradation of ATP or adenosine, (3) global regulatory genes, and (4) genes whose contribution to the ATP regeneration is unknown. Furthermore, the high glutathione productivity of Δ nlpD , the highest glutathione-producing mutant strain, was due to its reduced sensitivity to the externally added ATP for ATP regeneration. This study showed that the Permeable Cell Assay was useful for improving the ATP-regenerating activity of E. coli for practical applications in various ATP-driven bioprocesses, much as that of glutathione production.     

A Basic Study on the Biological Monitoring for Vanadium—Effects of Vanadium on Vero Cells and the Evaluation of Intracellular Vanadium Contents

A high concentration of vanadium (V) has toxic effects on human and animals and is one of environmental pollutants. In the present study, we have conducted a fundamental study using cultured Vero cells from monkey kidney for the future environmental monitoring. Orthovanadate (VAN), one of V compounds, of 10⁻¹⁰ and 10⁻⁸ M did not affect the cell growth although the higher concentration of above 10⁻⁶ M VAN inhibited the cell growth accompanied with the decrease in cell numbers and morphological changes. Given that the washing method with ice-cold Li is also effective for determination of the cellular Na content, we used this method for the determination of the V content of the Vero cells. The V distributions in Vero cell; in the 10⁻³ M VAN solution, extracellular and intracellular were obtained as 1:0.564:0.036 and 1:0.662:0.098 at 60 and 120 min after the treatment of VAN. The intracellular V content was 10% of the applied concentration of VAN. Consequently, it was suggested that V concentration of 10⁻⁷ and 10⁻⁶ M in the tissue and environment, respectively, might become the threshold concentration; a criterion of the environmental contamination when we carry out environmental monitoring.     

Tim4 recognizes carbon nanotubes and mediates phagocytosis leading to granuloma formation

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Regulation of chondroitin sulfate biosynthesis by specific sulfation: acceptor specificity of serum {beta}-GalNAc transferase revealed by structurally defined oligosaccharides

The relationship between sulfation and polymerization in chondroitinsulfate (CS) biosynthesis has been poorly understood. In thisstudy, we investigated the specificity of bovine serum UDP-GalNAc:CS ß-GalNAc transferase responsible for chain elongationusing structurally defined acceptor substrates. They consistedof tetra- and hexasaccharide-serines that were chemically synthesizedand various regular oligosaccharides with a GlcA residue atthe nonreducing terminus, prepared from chondroitin and CS usingtesticular hyaluronidase. The enzyme preparation was obtainedfrom fetal bovine serum by means of heparin-Sepharose affinitychromatography. The preparation did not contain the     

1H- and 13C-n.m.r.-spectral study of synthetic methyl d-manno-oligosaccharides

¹H- and ¹³C-n.m.r. spectra for 16 synthetic methyl manno-oligosaccharides were recorded, and the signals for the anomeric protons and anomeric carbon atoms in branched manno-pentaosides and -hexaosides were assigned, based on the data for methyl manno-biosides and -triosides. These n.m.r. data identified the branching pattern of high-mannose types of glycans of glycopeptides with those of unambiguously synthesized manno-oligosaccharides, and confirmed the structures proposed for such glycans.     

Construction of a Contiguous 874-kb Sequence of the Escherichia coli-K12 Genome Corresponding to 50.0-68.8 min on the Linkage Map and Analysis of Its Sequence Features

The contiguous 874.423 base pair sequence corresponding to the50.0–68.8 min region on the genetic map of the Escherichiacoli K-12 (W3110) was constructed by the determination of DNAsequences in the 50.0–57.9 min region (360 kb) and twolarge (100 kb in all) and five short gaps in the 57.9–68.8min region whose sequences had been registered in the DNA databases.We analyzed its sequence features and found that this regioncontained at least 894 potential open reading frames (ORFs),of which 346 (38.7%) were previously reported, 158 (17.7%) werehomologous to other known genes, 232 (26.0%) were identicalor similar to hypothetical genes registered in databases, andthe remaining 158 (17.7%) showed no significant similarity toany other genes. A homology search of the ORFs also identifiedseveral new gene clusters. Those include two clusters of fimbrialgenes, a gene cluster of three genes encoding homologues ofthe human long chain fatty acid degradation enzyme complex inthe mitochondrial membrane, a cluster of at least nine genesinvolved in the utilization of ethanolamine, a cluster of thesecondary set of 11 hyc genes participating in the formate hydrogenlyasereaction and a cluster of five genes coding for the homologuesof degradation enzymes for aromatic hydrocarbons in Pseudomonasputida. We also noted a variety of novel genes, including twoORFs, which were homologous to the putative genes encoding xanthinedehydrogenase in the fly and a protein responsible for axonalguidance and outgrowth of the rat, mouse and nematode. An isoleucinetRNA gene, designated ileY , was also newly identified at 60.0min.