Taxonomic studies of nectrioid fungi in Japan. III. The genus <Emphasis Type="Italic">Cosmospora</Emphasis>

Seven species of the genus Cosmospora collected in Japan are reported in this article. Among them, Cosmospora japonica is described as a new species. Cosmospora henanensis, C. rishbethii, and C. triqua, all of which are known only from their type localities, are added to the Japanese mycobiota. The other species, C. chaetopsinaecatenulatae, C. diminuta, and C. peponum, are new records for Japan. Additional distribution records are given for Cosmospora species hitherto known in Japan.     

Simple preparations of alkyl and cycloalkyl alpha-glycosides of maltose, cellobiose, and lactose

Alkyl, cycloalkyl, allyl, 4-pentenyl, and benzyl alpha-glycosides of maltose, cellobiose, and lactose were prepared (17-77% yield; alpha/beta=70/30-96/4) via a direct reaction of the free disaccharides with a binary AcBr-AcOH mixture, followed by glycosidation with alcohol using FeCl3 in MeNO2 or CH2Cl2, Zemplén deacetylation, and resolution of the anomeric mixture of glycosides by chromatography. Using MeCN as solvent for the glycosidation step, the corresponding beta-biosides were also prepared (16-61% yield; alpha/beta=25/75-5/95).     

Purification and properties of betaine aldehyde dehydrogenase from<Emphasis Type="Italic"> Avena sativa</Emphasis>

Betaine aldehyde dehydrogenase (BADH; EC 1.2.1.8) is the enzyme that catalyzes the second step in the synthesis of the osmoprotectant, glycine betaine. NAD-dependent BADH was purified from Avena sativa shoots by DEAE Sephacel, hydroxyapatite, 5′-AMP Sepharose 4B, Mono Q and TSK-GEL column chromatographies to homogeneity by the criterion of native PAGE, and the properties of BADH were compared with those of aminoaldehyde dehydrogenase purified to homogeneity from A. sativa. The molecular mass estimated by both gel filtration using TSK-GEL column and Sephacryl S-200 was 120 and 115, kDa, respectively. The enzyme is a homodimer with a subunit molecular mass of 61 kDa as shown by SDS-PAGE. The pI value of the enzyme was found to be 6.3. The purified enzyme catalyzed not only the oxidation of betaine aldehyde (BAL), but also that of aminoaldehydes, 3-aminopropionaldehyde (APAL), 4-aminobutyraldehyde (ABAL), and 4-guanidinobutyraldehyde (GBAL). The K _m values for BAL, APAL, ABAL and GBAL were 5×10⁻⁶, 5.4×10⁻⁷, 2.4×10⁻⁵ and 5×10⁻⁵ M, respectively. APAL showed substrate inhibition at a concentration of 0.1 mM. A fragment of BADH cleaved by V8 protease shared homology with other plant BADHs. Electronic Publication     

Photosynthesis-dependent removal of 2,4-dichlorophenol by Chlorella fusca var. vacuolata

Of 7 green algae, Chlorella fusca var. vacuolata removed about 23% of 2,4-dichlorophenol (DCP) at 10–80 M after 4 d when grown photoautotrophically. Removal of DCP was growth-dependent and was suppressed dose-dependently by the photosynthesis inhibitor, 3-(3,4-dichlorophenyl)-1,1-dimethyl urea.     

Pseudocospeciation of the mycoparasite Cosmospora with their fungal hosts

Species of Cosmospora are parasites of other fungi (mycoparasites), including species belonging to the Xylariales. Based on prior taxonomic work, these fungi were determined to be highly host specific. We suspected that the association of Cosmospora and their hosts could not be a result of random chance, and tested the cospeciation of Cosmospora and the their hosts with contemporary methods (e.g., ParaFit, PACo, and Jane). The cophylogeny of Cosmospora and their hosts was found to be congruent, but only host‐parasite links in more recent evolutionary lineages of the host were determined as coevolutionary. Reconciliation reconstructions determined at least five host‐switch events early in the evolution of Cosmospora. Additionally, the rates of evolution between Cosmospora and their hosts were unequal. This pattern is more likely to be explained by pseudocospeciation (i.e., host switches followed by cospeciation), which also produces congruent cophylogenies.     

Congenital goiter sustaining normal level of serum triiodothyronine

We attempted to elucidate the deficient site of thyroid hormone biosynthesis in the thyroid gland and the mechanism of sustaining normal T3 level in sera of a patient with congenital goiter. TY, a 8-yr-old boy, first noted the onset of a diffuse goiter at the age of 2. There was no clinical evidence of hypothyroidism except for the slight impairment of intellectual development and the awkward physical activity. BMR, T3-RSU and T4 showed low values (-13%, 20.8% and 2.2 micrograms/dl), but serum T3 was normal (180 ng/dl). Serum TSH was 18 microU/ml. The intrathyroidal T3 and T4 were slightly low. Thyroidal 131I uptake was high, but KSCN discharge test was negative. Percent distribution of 131I labelled amino acids in the pancreatin digested thyroid homogenate was 17.4% in MIT, 33.4% in DIT and 11.3% in T3 and T4. Thyroid iodide peroxidase activities in mitochondrial and microsomal fractions were slightly low (19.6 and 26.8 (normal: 32 +/- 3.0 and 37.4 +/- 9.5) mumoles/mg protein). The activity was not increased by the addition of hematin. Thyroglobulin was found to be normal. A biological half life of 131I labelled T4 was shorter (3.5 days) than that of the normal. Electron microscopic examination exhibited the increment and expansion of endoplasmic reticulum in the follicular cell. Low iodide peroxidase activity of this patient may correlate to low T3 and T4 level in the thyroid cell. Moreover, shortened biological half life of T4 implies that normal T3 level in serum is sustained by the accelerated conversion of T4 to T3 in peripheral tissues.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effects of histamine and related compounds on the release of immunoreactive thyrotropin-releasing hormone from the rat stomach in vitro

Effects of histamine and related compounds on the release of immunoreactive thyrotropin-releasing hormone (ir-TRH) from the rat stomach in vitro were studied. The rat stomach was incubated in medium 199 with 1.0 mg/ml of bacitracin and 100 micrograms/ml of ascorbic acid (pH 7.4) for 20 min. The amount of TRH release into the medium was measured by radioimmunoassay. The ir-TRH release from the rat stomach was enhanced significantly in a dose-related manner with the addition of histamine and inhibited with the addition of famotidine, but not with mepyramine. The stimulatory effect of histamine on ir-TRH release from the stomach was partially blocked with the addition of famotidine, but not with mepyramine. The elution profile of acid-methanol-extracted rat stomach on Sephadex G-10 was identical to that of synthetic TRH. These findings suggest that histamine stimulated ir-TRH release from the rat stomach in vitro, and that histamine's effects may be mediated via a H2-receptor.     

Effects of calcium hopantenate on the release of thyrotropin-releasing hormone from the rat adrenal gland in vitro

The effects of calcium hopantenate (HOPA), a GABA agonist, on the release of thyrotropin-releasing hormone (TRH) from the rat adrenal gland were studied in vitro. The adrenal glands were incubated in medium 199 with 1.0 mg/ml of bacitracin (pH 7.4) (medium) for 20 min. The amount of TRH release into the medium was measured by radioimmunoassay. The TRH release from the rat adrenal gland was inhibited significantly in a dose-related manner with the addition of HOPA to the medium. HOPA's effects on TRH release from the adrenal gland were blocked with the addition of bicuculline, a GABA receptor inhibitor. The elution profile of methanol-extracted rat adrenal gland TRH was identical to that for synthetic TRH. The findings suggest that HOPA inhibits TRH release from the rat adrenal gland, and that its effects are mediated via the GABA receptor.