Elongation factor-2 in chick embryo is phosphorylated on tyrosine as well as serine and threonine.

An endogenous 95 kDa chick embryo cytosolic protein (p95) was phosphorylated in the presence of [gamma-32P]ATP and the kinase activity for p95 was mostly associated with particulate fraction. Phosphorylation of p95 was prominent in embryos of early developmental stage. Hydrolysis of p95 phosphoprotein yielded phosphotyrosine in addition to phosphothreonine and phosphoserine. Native p95 was also tyrosine-phosphorylated. p95 phosphoprotein was purified by DEAE-Sephacel chromatography and immunoprecipitation with anti-phosphotyrosine antibody and the amino acid sequence was determined. The N-terminal sequence, Val-Asn-Phe-Thr-Val-Asp-Gln-Ile-Arg-Ala-Ile-Met-Asp- Lys-Lys-Ala-Asn-Ile-Arg-Asn-Met-, was found to be identical to those of elongation factor-2 (EF-2) of both rat and hamster. Our results suggest the presence of other EF-2 kinase in chick embryo cell than the previously reported Ca2+/calmodulin-dependent protein kinase III.     

Suppression of Th2-driven, allergen-induced airway inflammation by sauchinone

Sauchinone, a lignan compound isolated from the root of Saururus chinensis, has been recently demonstrated to exhibit anti-inflammatory activity via the suppression of NF-kB p65 activity in vitro. In an effort to evaluate the in vivo anti-inflammatory function of sauchinone, we have evaluated the effects of sauchinone on allergen-induced airway inflammation using a murine model of allergic asthma. We observed that marked eosinophilic and lymphocyte infiltration in the BAL fluid were suppressed to a significant degree by sauchinone, and that mucus-secreting goblet cell hyperplasia and collagen deposition in the airways were also ameliorated by administration of sauchinone treatment. Moreover, gene expression of the inflammatory cytokines, IL-13, and IL-5 and eotaxin in the lung, and IL-5 in the draining lymph node were significantly decreased in sauchinone-treated mice. We demonstrated that sauchinone repressed Th2 cell development in vitro and IL-4 production by Th2 cells, and also inhibited GATA-3-mediated IL-5 promoter activity in a dose-dependent manner. Collectively, sauchinone ameliorated allergen-induced airway inflammation, in part, by repressing GATA-3 activity for Th2 cell development, indicating the possible therapeutic potential of sauchinone in airway inflammatory diseases including allergic asthma and rhinitis.     

Cloning of ribosomal protein S6 kinase cDNA and its involvement in meiotic maturation in Rana dybowskii oocytes

Several protein kinases are involved in the meiotic maturation of frog oocytes in order to activate the maturation-promoting factor (MPF). Among these kinases, the 90 kDa ribosomal protein S6 kinase (p90Rsk or Rsk) is directly phosphorylated and activated by the mitogen-activated protein kinase (MAPK). During Xenopus oocyte maturation, the activation of Rsk closely parallels that of MAPK. Both enzymes are dephosphorylated when the cytostatic factor (CSF) disappears after fertilization. Therefore, Rsk seems to play an essential role in the activation of MPF. To evaluate it in other frog oocytes, we cloned and characterized Rsk cDNA in Rana dybowskii oocytes. The cloned Rana Rsk cDNA had 2,961 bp of nucleotides, which contained a complete single open-reading frame with ATG codon and polyadenylation signal. The deduced amino acid sequence of Rana Rsk is 733 amino acids with 83 kDa. Rana Rsk shows a high homology (about 88%) with Xenopus Rsk. It also had two well-conserved kinase domains with specific phosphorylation sites, which are known to be essential for the activation of Rsk. A Northern analysis showed that Rana Rsk mRNA was strongly expressed in ovary tissue, but weakly in other tissue. Rana Rsk protein is expressed with the pTYB1 vector and purified with the IMPACT-CN system. The purified Rana Rsk cross-reacted with Xenopus, a p90Rsk2 antiserum. Therefore, we examined the phosphorylation of Rana Rsk during Rana oocyte maturation. In P4-treated oocytes, Rana Rsk was phosphorylated about 6-9 h, which correlated well with the germinal vesicle breakdown of Rana oocytes. Therefore, it is likely that Rana Rsk plays an important role in the meiotic maturation of seasonal breeding animals.     

Complete genome sequence of Bifidobacterium longum subsp. longum KACC 91563

Bifidobacterium longum strains predominate in the colonic microbiota of breast-fed infants. Here we report the complete genome sequence of B. longum subsp. longum KACC 91563, isolated from feces of neonates. A single circular chromosome of 2,385,301 bp contains 1,980 protein-coding genes, 56 tRNA genes, and 3 rRNA operons.     

The first report of the genus Tetramoera Diakonoff (Lepidoptera: Tortricidae) with description of a new species from the Korean peninsula

In the present study, the genus Tetramoera Diakonoff is reported for the first time from the Korean Peninsula. Also a new species of the genus, Tetramoera bongwaensis sp. nov., is described as new to sciences. Photographs of the adults and male genitalia are presented.     

Effect of the weak Ca(2+)-binding site of subtilisin J by site-directed mutagenesis on heat stability.

The functional role of the negatively charged amino acid residue in subtilisin J from Bacillus stearothermophilus has been investigated by site-directed mutagenesis. Glu-195 located at the weak Ca2+-binding site was replaced with Gln to examine the role of Glu-195 in the heat stability of subtilisin J. Mutant enzyme was expressed in Bacillus subtilis and was purified from the culture supernatant. When the mutant enzyme was expressed at 37 degrees C in the presence of 2mM calcium chloride, the pattern of enzyme production was quite different from that of wild-type. The purified Gln-195 mutant enzyme was analyzed with respect to optimal temperature, optimal pH, and heat stability. The mutation was found to decrease the heat stability but not catalytic efficiency (kcat/Km) and optimal pH. These results demonstrate the important role of the negatively charged side chains at the weak Ca(2+)-binding site in the heat stability of subtilisin.     

Regulation of proteins related to melanogenesis by heartwood extract of<Emphasis Type="Italic">Morus bombycis</Emphasis> using proteome analysis

The ability of heartwood extract ofMorus bombycis in controlling the melanogenesis in B16 melanoma was investigated. An inhibitory effect was observed when the dose concentration was less than 10 mg/L. When the dose was 10 mg/L, the extracellular melanin accumulated was only 5% of the control. Proteome analysis with 2-D PAGE and MALDI-TOF showed that there were various proteins involved in inhibitory melanogenesis. It seems that down-regulation of TRP2, vacuolar protontranslocating ATPase 100 kDa subunit isoform a1-I and V-ATPase E2 subunit were involved in melanosome development and regulation that could reduce melanin synthesis.     

Elicitation kinetics of taxane production in suspension cultures of Taxus baccata Pendula

Methyl jasmonate increased taxane production in suspension cultures of Taxus baccata Pendula. Time course changes of taxane production after methyl jasmonate addition were different from normal kinetics without elicitation. Baccatin III and 10-deacetyl baccatin III were detected first and paclitaxel, 10-deacetyl taxol and cephalomanine followed each other in sequence. Paclitaxel was not a dead-end metabolite.     

The leader sequence of streptokinase is responsible for its post-translational carboxyl-terminal cleavage

When the expression of streptokinase from two tac promoter-controlled expression vectors, one of these deleted a putative leader sequence of streptokinase and the other not, was compared, both normal and degraded streptokinase were detected in proteins expressed from the leader-contained vector, but only normal streptokinase was detected from the leader-deleted vector. These findings indicate that the characteristic carboxyl-terminal cleavage of streptokinase is correlated with its leader sequence and occurs during the defective secretion. The homogeneous preparation of streptokinase was facilitated by expressing from this leader-deleted vector.