Studies on the structure of a novel peptide antibiotic, K-582

A novel peptide antibiotic, K-582, which exhibited significant growth inhibition of Candida, viruses and ascites tumor in mice, was found in the culture medium of a strain of Metarhizium anisopliae by Kondo et al. (J. Antibiotics 33, 535-542 (1980) ]. K-582 consisted of two components, designated K-582 A and K-582 B. Threonine, tyrosine, ornithine, and an unusual amino acid were common in both peptides, but lysine was an extra component of K-582 A. The unusual amino acid was identified to be threo-gamma-hydroxy-L-arginine (OHArg) by means of mass, nuclear magnetic resonance and infrared spectrometries of the derivatives and the related compounds. The threonine and the arginine were assigned to be L-configuration, and the ornithine and the tyrosine to be D-configuration in both K-582 A and K-582 B, and the lysine to be L-configuration by comparison of their optical rotatory dispersion spectra with those of standard amino acids. The elucidation of primary structure revealed that they were closely related heptapeptides with the following sequence: K-582 A:H-Arg-OHArg-Orn-Thr-Orn-Lys-Tyr-OH; K-582 B:H-Arg-OHArg-Orn-Thr-Orn-OHArg-Tyr-OH, and had the identical sequence in terms of the configuration of their constituents, namely L-L-D-L-D-L-D.     

Studies on the formation of germ cells in a compound ascidian Botryllus,primigenus oka

Gametogenesis of a compound ascidian Botryllus primigenus was studied histologically. On either side of the zooid (stage 9), in the gonadal space between the epidermis and the atrial epithelium, either a single testis or a complex of an egg follicle and a testis can be formed. The egg follicle consists of a single ovum (occasionally two ova) and its accessory cells and is connected with the atrial epithelium by the follicle stalk. The egg follicle is always accompanied by the brood pouch, a diverticulum of the atrial cavity. The testis is equipped with a vestigial spermiduct and is attached to the atrial epithelium. Buds of stage 8 comprise, besides the developing testes and, egg follicles, loose aggregations of hemoblasts and oocytes of early developmental stages, which are already accompanied by primary follicular cells. Both the oocytes and the primary follicular cells seem to arise from the hemoblasts. The young oocytes are isolated in the gonadal space of the buds nnd are transferred to buds of the succeeding generations until they finally mature. In the bud of stage 3, a compact mass of cells appears, attaching to tbe inner vesicle on either side of the body. It is derived from the hemoblasts lodged there in the preceding generation and presumably also from the circulating hemoblasts. When the cell mass receives a large oocyte derived from the preceding generation, part of the cell mass differentiates into egg envelopes, forming an egg follicle, and a follicle stalk and the remainder into a testis. When the cell mass receives no oocyte, it differentiate as a whole into a testis. In the egg follicle thus formed the outer and inner follicular cells increase in number by mitotic division. Subsequently, initial test cells are derived from the inner follicle by migration across the developing chorion; then they increas2 in number by mitosis. In the testis, meiosis and spermiogenesis take place.     

Partial characterization of the secretory material from the dorsal bodies in the snail Helisoma duryi (Mollusca: Pulmonata), and its effects on reproduction

Abstract. Both dorsal body tissue extracts and dorsal body-conditioned medium stimulated in vitro polysaccharide synthesis in albumen gland explants in Helisoma duryi . This activity is heat- and protease-resistant. Dorsal body tissue extracts and dorsal body-conditioned medium were passed through solid-phase extraction cartridges, then eluted with increasing concentrations of methanol (20%, 70%, and 100%) and the various eluates tested for their biological activity. An active factor was found in the 100% methanol wash from both dorsal body tissue extracts and the conditioned medium. In addition, another bioactive factor in the conditioned medium eluted with 70% methanol. The endocrine dorsal bodies in the freshwater snail H. duryi were maintained in vitro , and following incubation, the culture medium was collected and tested for the presence of ecdysteroids. Radioimmunoassay of the culture medium demonstrated the presence of ecdysteroid-like immunoreactivity, suggesting the dorsal bodies are capable of secreting ecdysteroids in vitro . Identification of released ecdysteroids by HPLC/RIA revealed a number of immunoreactive fractions, which were tested for bioactivity. To test for possible physiological functions of ecdysteroids in Helisoma duryi , 20-hydroxyecdysone (a potent ecdysteroid in arthropods) was injected into non-egg laying (virgin) snails. Injections of ecdysteroid induced low egg-laying activity and the maturation of oocytes in the ovotestis. Incubation of albumen glands with ecdysteroid stimulated polysaccharide synthesis. The results are discussed in relation to the possible function(s) of ecdysteroids in pulmonate snails.     

Genetic diversity of the cytoplasm in Triticum and Aegilops

Summary Twelve kinds of common wheat nuclei were placed into the cytoplasms of 23 species of Aegilops and Triticum by repeated backcrosses in the Laboratory of Genetics, Kyoto University. Using these nucleus-cytoplasm hybrids, the distribution of the variegation-inducing cytoplasms was investigated. The variegation was maternally inherited, and was found to be temperature-dependent; it was expressed only at low temperatures, accompanied by a remarkable reduction in the content of chlorophyll a and b, and recovered to almost normal level in a greenhouse kept at 25 °C. The variegation was expressed only by special combinations of the wheat nuclei and alien cytoplasms; nine common wheat nuclei, Tve, P168, CS, N26, Slm, Sk, S615, Sphr, and Splt, and six cytoplasms, T. boeoticum, Ae. umbellulata, Ae. triuncialis, Ae. biuncialis, Ae. columaris, and Ae. triaristata 6x, expressed weak to strong variegation in almost all combinations. Combinations of three common wheat nuclei (JF , Comp and Macha) and 17 other cytoplasms showed no variegation: JF , Comp and Macha appeared to have a sort of restoring gene(s) against variegation. Since distribution of the variegation-inducing cytoplasms was confined to the A and C^u type plasmas, it was assumed that the plasmagene(s) responsible for the variegation originated in the diploid level and was transmitted from Ae. umbellulata to three tetraploid and one hexaploid species of Polyeides section through the process of amphidiploidization.Contribution from the Laboratory of Genetics, Faculty of Agriculture, Kyoto University, No. 399. The present work was supported in part by a Grant-in-Aid (No. 036023) from the Ministry of Education, Japan.     

Nonradioactive labeling with chemically modified cytosine tails by the polymerase chain reaction.

We developed a modified nonradioactive method for the detection of DNA. This method makes use of the polymerase chain reaction for preparation of probes; that is, a DNA fragment inserted in the polylinker region of an M13 or pUC vector is amplified with primers that have a modified cytosine tail at the 5' terminus (C-tailed primers). By this method, large amounts of labeled probes can be obtained easily. After hybridization, modified cytosine tails can be detected immunologically. DNA labeled by this method could be used in plaque hybridization. We could detect 0.05 pg of dot-blotted labeled DNA in 30 min with an enzyme-catalyzed chemiluminescence reaction.     

Synthesis of deoxynucleoside-5'-tri-3'-diphosphates by Streptomyces adephospholyticus ATP:nucleotide pyrophosphokinase

ATP: nucleotide pyrophosphokinase (EC 2.7.6.4.) of Streptomyces adephospholyticus catalyzes an efficient transfer of the 5′-β,γ-pyrophosphoryl group of dATP to the four common deoxynucleoside-5′-triphosphates at their 3′-OH positions in the alkaline pH and in the presence of Co²⁺ ions, giving the respective 3′-pyrophosphoryl derivatives. Deoxyadenosine-5′-tri-3′-diphosphate was chromatographically prepared and structurally characterized.     

Light-Independent and Tissue-Specific Accumulation of Light-Harvesting Chlorophyll a/b Binding Protein and Ribulose Bisphosphate Carboxylase in Dark-Grown Pine Seedlings

The presence of light-harvesting chlorophyll a/b binding proteinsand the small and large subunits of ribulose bisphosphate carboxylasewas revealed in dark-grown pine seedlings. The light-independentaccumulation of the proteins was observed in photosyntheticand/or green tissue, such as cotyledons and hypocotyls, butnot in non-photosynthetic roots. ¹ This work was supported by Grants-in-Aid from the Ministryof Agriculture, Forestry and Fisheries of Japan (IntegratedResearch Program for the Use of Biotechnological Proceduresfor Plant Breeding), and from the Science and Technology Agencyof Japan (Encouragement of Basic Research). (Received May 2, 1991; Accepted August 13, 1991)