Phylogenetic relationships ofPythium species based on ITS and 5.8S sequences of the ribosomal DNA

The sequences of ITS regions in 30 species and two groups of the genusPythium were resolved. In the phylogenetic trees, the species were generally divided into two clusters, referred to here as the F and S groups. The species in the two groups correspond in terms of their sporangial morphology, with the F group being filamentous/lobulate and the S group being spherical. Genetic divergence within the F group was lower than that within the S group. Other morphological characteristics such as oogonial structure and sexual nature appeared to be unrelated to the groupings in these trees. An alignment analysis revealed common sequences to all the species and arrangements specific to each F or S group. It was found that the ITS region was a good target in designing species-specific primers for the identification and detection ofPythium species. In the tree based on 5.8S rDNA sequences, oomycetes are distantly related to other fungi but separated from algae in Chromista.     

Epitope study and cDNA screening of major surface glycoprotein of Pneumocystis carinii.

Use of monoclonal antibodies against the major glycoprotein of Pneumocystis carinii (P115) implicated the sugar moiety as being strongly antigenic. Furthermore, monoclonal antibodies directed against the peptide portion of P115 were generated by using synthetic oligopeptides after amino acid sequencing was done on P115 proteolytic fragments.     

Lipolysis induction in adipocytes by a protein from tumor cells

Extracts of thymic lymphoma that are obtained from AKR mice and are kept in the cold for at least several days can induce lipolytic activity in rat adipocyte suspensions. Freshly prepared extracts have low activity but contain a low molecular weight material of less than 10,000 daltons that aggregates on standing in the cold and becomes active. Treatment of aged extracts with trypsin causes a loss in activity indicating that the active material is a protein. It has been obtained in partially purified form, is relatively heat stable, and is not a lipase. Activity was also demonstrated in AKRXDBA/2 lymphoma (induced by AKR SL3-3 virus) and in transplanted lymphomas from a Friend-virus-induced erythroleukemia cell line in DBA/2 mice, but was not detected in normal thymus, spleen, liver, or other tissues. The partially purified material produced a massive fat mobilization when injected into normal mice.     

A 460-kb DNA Sequence of the Escherichia coli K-12 Genome Corresponding to the 40.1-50.0 min Region on the Linkage Map

The 465,813 base pair sequence corresponding to the 40.1–50.0min region on the genetic map of Escherichia coli K-12 (W3110)was determined. Analysis of the sequence revealed that thisregion contained at least 466 potential open reading frames,of which 187 (40%) were previously reported, 105 (23%) werehomologous to other known genes, 103 (22%) were identical orsimilar to hypothetical genes registered in databases, and theremaining 71 (15%) did not show a significant similarity toany other gene. At the 45.2–46.0 min region, we founda very large cluster of about 30 genes, whose functions areinvolved in the biosynthesis of polysaccharides as the componentsof outer membranes. In addition, we identified anew asn-tRNAgene, designated asnW, between the asnT and asnU genes and anew lysogenic phage attachment site as the cis-element.     

Optimal conditions for blastogenic response of peripheral blood lymphocytes to T and B cell mitogens in cynomolgus monkeys

Optimal conditions for the mitogen-induced proliferation of T and B lymphocytes of cynomolgus monkeys were determined. The T cell mitogens concanavalin A and phytohemagglutinin, at concentrations of 1.25–10 μg/ml and 1.25–10 μg/ml, respectively, and the T and B cell mitogen pokeweed mitogen, at concentrations of 0.2–10 μg/ml, induced high lymphoproliferative responses, the average stimulation index (SI) being 34–93. Since suitable mitogens have not been reported for monkey B cells, we tested three types of lipopolysaccharide (LPS): two derived from Escherichia coli—one extracted with phenol and one extracted with trichloroacetic acid (TCA); and one derived from Salmonella typhimurium, extracted with phenol. All three LPS had a high mitogenic effect for monkey lymphocytes, with SI of 2.3–6.4. The highest response was observed for 25 μg/ml of Salmonella LPS, and the addition of trypsin to the culture augmented the proliferative response of low or non-responder lymphocytes. © 1994 Wiley-Liss, Inc.     

Expression of human pituitary adenylate cyclase activating polypeptide (PACAP) cDNA in CHO cells and characterization of the products.

cDNA encoding human PACAP precursor was expressed in non-neuroendocrine Chinese hamster ovary cells, CHO-K1, The cells were transfected with expression vector (pTS705) containing the human PACAP cDNA by electroporation. A cell line which produced more than 80 ng/ml of immunoreactive PACAP (ir-PACAP) into the conditioned medium was established. RP-HPLC analysis of culture medium of this established cell line exhibited the presence of two types of PACAP, i.e. PACAP38 and PACAP27. At the same time, it was also revealed that immunoreactive PACAP-related peptide (ir-PRP) was secreted into the cultured medium. The ir-PACAPs were confirmed to ahve biological activities such as induction of cAMP and neurite outgrowth in rat pheochromocytoma PC12h cells.     

Solution conformation of endothelin determined by nuclear magnetic resonance and distance geometry

The solution conformation of endothelium-derived vasoconstrictor peptide, endothelin, has been determined by two-dimensional 1H-NMR spectroscopy and distance geometry. Conformation in the N-terminal core region (residues 1-15) is well-defined and a characteristic is the helix-like conformation in the segment from Lys9 to Cys15. Contrarily, the C-terminal tail region (residues 16-21) does not assume a defined conformation and there are no specific interactions between the core and the tail regions.