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J Sugiyama

Publications and source records attributed to J Sugiyama.

At least 55 records · Page 3Linked to original sources

[Subserogrouping of 49 Legionella pneumophila serogroup 1 strains with monoclonal antibodies by slide latex agglutination method and its usefulness for epidemiologic study].

Legionella pneumophila serogroup (SG) 1 has been known as a most frequent and important causative bacteria of Legionella pneumonia. It was reported that antigenicity of the serogroup was composed by numerous antigenic factors. To study antigenic factor formula of Japanese isolates from both clinical and environmental sources together with Philadelphia 1 strain, we examined slide latex agglutination system with monoclonal antibodies for subsergorouping. Philadelphia 1 and GIFU10102 strain (environmental isolate) were used as immune strains based on a cross absorption test result by rabbit antisera. Five anti L. pneumophia SG1 monoclonal antibody-producing clones were established. All monoclonal antibodies were SG1 specific but showed different reactivities with strain to strain. We prepared monoclonal antibody sensitized latex and used for subserogrouping of isolated strains. Twenty-two clinical isolates from Legionella pneumonia patients and 26 environmental isolates were examined. Each strain was reacted with at least one of the 5 sensitized latex and its antigenic formula was designed by sensitized latex reaction pattern. As a total of 6 patterns demonstrated in clinical isolates and 7 patterns in environmental isolates, 48 L. pneumophila SG1 isolates were divided into 11 subserogroup patterns. The antigenic formula of Philadelphia 1 was same as one of clinical isolate patterns. It was considered that this subserogrouping system would be a useful tool for epidemiologic study.

Animals↗

Docking of congo red to the surface of crystalline cellulose using molecular mechanics.

A method for the docking of ligands to crystalline surfaces using molecular mechanics was developed and applied to study the molecular features of the adsorption of Congo Red to cellulose crystals. The docking procedure was based on a grid search exploring the surface repeat unit of the cellulose crystals using several orientations of Congo Red at each grid point. Results suggest a preferential adsorption of Congo Red onto certain faces of the cellulose crystals and that the lower energy conformers have a similar positioning and orientation with respect to the cellulose chains at the surface repeat unit.

Adsorption↗

A common group I intron between a plant parasitic fungus and its host.

The self-splicing RNAs known as group I introns exist in many organisms, but their distribution is difficult to explain. We hypothesize that group I introns have been transferred between a parasite and its host. We describe here the discovery of a common group I intron sequence between a plant-parasitic fungus, Protomyces inouyei, and its host, Youngia japonica. It strongly supports our theory that the group I intron had been transferred from the host plant to the parasitic fungus in the course of evolution.

Ascomycota↗

Dystroglycan binds nerve and muscle agrin.

Neurally released agrin is thought to cluster acetylcholine receptors (AChRs) and other synaptic proteins in the postsynaptic membrane during synaptogenesis at the neuromuscular junction. We have examined the binding of nerve and muscle agrins, which have dramatically different abilities to cluster AChRs, to the membrane proteins of Torpedo electric organ and C2 myotubes. Both bound with approximately nanomolar affinity to a single component identified as alpha-dystroglycan: agrin binding was blocked by antibodies to alpha-dystroglycan, and agrin bound to purified alpha-dystroglycan. Dystroglycan was altered in two genetic variants of C2 muscle cells that fail to form spontaneous clusters of AChRs and that show a diminished response to agrin. Antibodies that blocked alpha-dystroglycan binding, however, failed to block the clustering of AChRs by neural agrin. Although alpha-dystroglycan is the major agrin-binding protein in Torpedo and myotube membranes, its physiological role is unclear.

Agrin↗

[Superimposition of MR angiography and three dimensional radionuclide brain perfusion image with personal computer].

To investigate the correlation of arterial obstruction with brain perfusion, MR angiography (MRA) and three dimensional (3D) radionuclide brain perfusion image were superimposed. Eleven cases with intracranial artery obstructive patients were studied. Three dimensional brain perfusion images were generated based on the ray-tracing method. Superimposition of MRA on to 3D brain perfusion image was performed on a personal computer. Reconstructing time for 3D image was about 15 minutes for each patient, Superimposing time was about 5 minutes for each image. Correlation of arterial obstruction with decrease in brain perfusion was demonstrated clearly by superimposed image. With a personal computer, it was possible to produce clinically useful synthesized images with relatively short time and conveniently.

Adult↗

The higher fungus Protomyces inouyei has two group I introns in the 18S rRNA gene.

The nucleotide sequence of the small-subunit rRNA (18S rRNA) coding gene in the higher fungus Protomyces inouyei contains two group I introns. This is the first report of two group I introns in the 18S rRNA coding region. Based on the comparison of the two introns of Protomyces inouyei with those of the green alga Ankistrodesmus stipitatus, and the other two higher fungi Pneumocystis carinii and Ustilago maydis, the Protomyces introns are group I introns containing the highly conserved sequence elements P, Q, R, and S. Intron A of Protomyces inouyei is located in the same position as in Pneumocystis carinii while intron B shares the location with that in Ustilago maydis. The phylogenetic relationships strongly support horizontal transfer of these group I introns.

Ascomycota↗

Phylogenetic analysis of basidiomycetous yeasts by means of 18S ribosomal RNA sequences: relationship of Erythrobasidium hasegawianum and other basidiomycetous yeast taxa.

The basidiomycetous yeast genus Erythrobasidium Hamamoto, Sugiyama & Komagata, based on the type species E. hasegawianum Hamamoto et al., is characterized by filobasidiaceous basidia and the Q-10 (H2) system as its major ubiquinone. It is tentatively placed in the Filobasidiaceae. The molecular characterization is based on 18S ribosomal RNA sequence comparisons among the basidiomycetous yeasts, and the ultrastructural characterization on the cell wall and hyphal septal pores in E. hasegawianum clearly indicate a close relationship with the teliospore-forming yeasts Rhodosporidium toruloides and Leucosporidium scottii. Our molecular phylogeny with statistical analysis suggests that the existing taxonomic system of basidiomycetous yeasts, based primarily on the morphology of basidia including the teliospores (probasidia), should be revised.

Basidiomycota↗

Visualization of the adsorption of a bacterial endo-beta-1,4-glucanase and its isolated cellulose-binding domain to crystalline cellulose.

Endo-beta-1,4-glucanase A (CenA), a cellulase from the bacterium Cellulomonas fimi, is composed of two domains: a catalytic domain and a cellulose-binding domain. Adsorption of CenA and its isolated cellulose-binding domain (CBD.PTCenA) to Valonia cellulose microcrystals was examined by transmission electron microscopy using an antibody sandwich technique (CenA/CBD.PTCenA-alpha CenA IgG-protein A-gold conjugate). Adsorption of both CenA and CBD.PTCenA occurred along the lengths of the microcrystals, with an apparent preference for certain crystal faces or edges. CenA or CBD.PTCenA, but not the isolated catalytic domain, were shown to prevent the flocculation of microcrystalline bacterial cellulose. The cellulose-binding domain may assist crystalline cellulose hydrolysis in vitro by promoting substrate dispersion.

Actinomycetales↗

Phylogenetic relationships among Taphrina, Saitoella, and other higher fungi.

To determine the phylogenetic placement of the major groups of higher fungi, we sequenced the DNA sequences from the small-subunit ribosomal RNA (18S rRNA) coding regions from Taphrina wiesneri (synonym: T. cerasi) and Saitoella complicata and compared them to 18S rRNA sequences from the oomycetes, chytridiomycetes, zygomycetes, ascomycetes, and basidiomycetes. Here we demonstrate that the ascomycetes have at least two major evolutionary lineages. Taphrina wiesneri and Saitoella complicata form a monophyletic branch that diverged prior to the separation of other ascomycetes. The same treatment could be accorded to Schizosaccharomyces pombe.

Ascomycota↗

Molecular systematics of the genus Zoogloea and emendation of the genus.

Phylogenetic relationships among strains of Zoogloea and related taxa were determined by 16S rDNA sequencing and genomic DNA hybridization techniques. The 16S rRNA gene was amplified by the polymerase chain reaction with a pair of eubacterial consensus primers and sequenced directly by using an automated fluorescent DNA sequencer. Sequence comparisons and distance matrix tree analysis revealed that Zoogloea ramigera IAM 12136 (= N. C. Dondero 106, type strain) and Zoogloea sp. ATCC 19324 formed a lineage with Rhodocyclus purpureus in the beta subclass of Proteobacteria. Z. ramigera IAM 12670 (= P. R. Dugan 115) was shown to belong to another cluster with Alcaligenes eutrophus and Pseudomonas cepacia in the beta subclass. In contrast, Z. ramigera IAM 12669 (= K. Crabtree I-16-M) proved to be a member of the alpha subclass of the Proteobacteria, closely related to Agrobacterium tumefaciens. Genomic DNA hybridization studies also showed that there is genetic diversity among the strains currently designated Z. ramigera, but typical Zoogloea strains, characterized by their production of rhodoquinones, are highly related to each other and can be regarded as a single species. On the basis of the molecular data, together with the early phenotypic and chemotaxonomic information, we have emended the generic description of Zoogloea.

Base Composition↗

Phylogeny among the basidiomycetous yeasts inferred from small subunit ribosomal DNA sequence.

The sequence of the small subunit nuclear ribosomal DNA (18S rDNA) was determined for seven selected species of the teliospore-forming yeasts and Filobasidiaceae in the basidiomycetous yeasts. A phylogenetic tree, including published reference sequences, was inferred from 1623 sites which could be unambiguously aligned. The molecular phylogeny, using a chytridiomycete as an outgroup, divided the eight basidiomycetous yeasts into two groups which correlated well with both septal ultrastructure (simple pore or dolipore) and cellular xylose (present or absent). The first group included the teliospore-forming yeasts Rhodosporidium toruloides and Leucosporidium scottii, and Erythrobasidium hasegawianum, which is currently a member of the Filobasidiaceae. The second group was formed by the filobasidiaceous yeasts, comprising a Cystofilobasidium capitatum/Leucosporidium lari-marini/Mrakia frigida branch, and a Filobasidium floriforme/Filobasidiella neoformans branch. Our molecular data support the principal chemotaxonomic and ultrastructural evidence, which indicates a very close affinity between C. capitatum and L. lari-marini.

Basidiomycota↗

Evolutionary position of n-alkane-assimilating yeast Candida maltosa shown by nucleotide sequence of small-subunit ribosomal RNA gene.

We clarified the evolutionary position of Candida maltosa, an n-alkane-assimilating yeast, by sequencing the nucleotides of the small-subunit ribosomal RNA gene. Phylogenetic analyses showed the close evolutionary relationships of C. maltosa with C. tropicalis, C. viswanathii, C. albicans, C. parapsilosis, and C. guilliermondii, forming a sub-group within this genus.

Alkanes↗