Production de deux glycopeptides par le Phialophora cinerescens (Wr.) van beyma cultive in vitro

Résumé Le Phialophora cinerescens alcalinise nettement le milieu liquide sur lequel il est cultivé durant 7 semaines; Le saccharose fourni est rapidement hydrolysé en glucose et fructose. La production des deux glycopeptides neutre et anodique — qui affectent la croissance des jeunes plantes d'Oeillet — a été appréciée. Le glycopeptite neutre est synthétisé dès le début de la culture, le glycopeptide anodique plus tardivement; les variations de la croissance du P. cinerescens cultivé in vitro suggèrent que les deux glycopeptides ne sont pas des produits de l'autolyse du mycélium.

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In vitro growth of the fungus Phialophora cinerescens was studied for 7 weeks. During this period the pH values were shown to increase in the culture filtrates; the added sucrose was rapidly hydrolyzed into glucose and fructose. The production of both neutral and anodic glycopeptides — which are know to affect the growth of carnation seedlings — was periodically monitored. The neutral glycopeptide was synthesized at the beginning of the culture period, the anodic one was synthesized later. The P. cinerescens growth curves indicated these two metabolites were probably not autolytic products of fungal cells.

     

Establishment of phosphate-solubilizing strains of Azotobacter chroococcum in the rhizosphere and their effect on wheat cultivars under green house conditions

A pot experiment was conducted in the green house to investigate the establishment of phosphate solubilizing strains of Azotobacter chroococcum, including soil isolates and their mutants, in the rhizosphere and their effect on growth parameters and root biomass of three genetically divergent wheat cultivars (Triticum aestivum L.). Five fertilizer treatments were performed: Control, 90 kg N ha^—1, 90 kg N + 60 kg P₂O₅ ha^—1, 120 kg N ha^—1 and 120 kg N + 60 kg P₂O₅ ha^—1. Phosphate solubilizing and phytohormone producing parent soil isolates and mutant strains of A. chroococcum were isolated and selected by an enrichment method. In vitro phosphate solubilization and growth hormone production by mutant strains was increased compared with soil isolates. Seed inoculation of wheat varieties with P solubilizing and phytohormone producing A. chroococcum showed better response compared with controls. Mutant strains of A. chroococcum showed higher increase in grain (12.6%) and straw (11.4%) yield over control and their survival (12—14%) in the rhizosphere as compared to their parent soil isolate (P4). Mutant strain M37 performed better in all three varieties in terms of increase in grain yield (14.0%) and root biomass (11.4%) over control.     

Genetic linkage relationships between two enzyme loci,Est-2 and acph,in the mosquito Aedes (Finlaya) togoi

An esterase locus (Est-2), coding for carboxylesterase, and an acid phosphatase locus (Acph) were genetically studied by agar gel electrophoresis in the mosquito Aedes (Finlaya) togoi. The Est-2 and Acph variants occur as a monomer and a dimer, respectively. Both enzyme loci are linked to the sex locus (M) and s (straw-colored larva); the gene arrangement and recombination distances were Est-2—12.6%—s—31.7%—M—2.9%—Acph—3.2%—Est-3. The Est-3 locus was previously shown to code for carboxylesterase.This work was supported by Grant AI 16983-02 from the National Institutes of Health, Bethesda, Md.     

NeueSilene-Arten (Caryophyllaceae) aus dem Gebiet der Flora Iranica

15 new species are described: Sect.Sclerocalycinae:S. farsistanica, S. stapfii. — Sect.Spergulifoliae:S. paktiensis. — Sect.Auriculatae:S. caroli-henrici, S. daënensis, S. gertraudiae, S. nizvana, S. oligophylla, S. persepolitana, S. pseudaucheriana, S. pseudonurensis, S. renzii, S. salangensis, S. sojakii. — Sect.Brachypodae:S. rasvandica. — All the new species are from Iran with exception ofS. paktiensis andS. parvanica which are from Afghanistan.

Florae Iranicae praecursores 46–60. — Praecursores praecurrentes in Pl. Syst. Evol.142: 239–246 (1983).     

Linkage of lactate dehydrogenase-2, Ldh-2, in the mouse

An electrophoretically detectable variant of lactate dehydrogenase-2 in Mus musculus has been found and used to locate the structural gene, Ldh-2, on chromosome 6. Gene order and recombination frequencies are estimated as Sig—36.0±4.8—Lc 21.0±4.1—Mi ^wh—20.0±4.0—Ldh-2.     

Entomophthora apiculata (Thaxter) Gustafs. (Zygomycetes,Entomophthorales) as a pathogen of calypterate flies in Nigeria

Entomophthora apiculata (Thaxter) Gustafs. was isolated from the following naturally-infected dipterans: Musca domestica L. (s.l.) (Muscidae); Hemipyrellia fernandica Macquart and Chrysomya chloropyga f. putoria Weidemann (Calliphoridae). This fungus produced rhizoids in vivo but not in vitro. Although it was readily cultured in vitro, experimental infection could not be achieved consistently — which calls for intensive research into the biology of this and other Entomophthora species.     

Omphalotaceae fam. nov. undPaxillaceae,ein chemotaxonomischer Vergleich zweier Pilzfamilien derBoletales

TheOmphalotaceae fam. nov., which include the generaOmphalotus andLampteromyces, are defined on the basis of characteristic sesquiterpenes and of their ability to cause white-rot. Anatomical and morphological features of the representatives of these genera support the creation of this new family. The occurrence of pigments, typical of theBoletales, and of cyanophilous spores, indicate membership of theOmphalotaceae in the orderBoletales. Relationships to the other families of this order — especially to thePaxillaceae — are discussed. The possible functional significance of fungal metabolites is considered.

Herrn Prof. Dr.J. Poelt zur Vollendung seines 60. Lebensjahres gewidmet.—Veränderte Fassung eines Vortrages auf der Tagung der Deutschen Botanischen Gesellschaft, Wien, September 1984.     

Strain difference (WKY,SPRD) in the hepatic antioxidant status in rat and effect of hypertension (SHR,DOCA). Ex vivo and in vitro data

We assessed the hepatic antioxidant status of spontaneously (SHR) and desoxicorticosterone acetate (DOCA)-induced hypertensive rats and that of respective normotensive Wistar Kyoto (WKY) and Sprague-Dawley (SPRD) rats. For this we evaluated, ex vivo in liver cytosols, reduced glutathione (GSH) content, glutathione-related enzyme (peroxidase, reductase and transferase) activities as well as the rate of lipid peroxidation in 9–11 week-old rats. The antioxidant status and the cytotoxicity of acetaminophen, a radical- and hydrogen peroxide-mediated hepatotoxic compound, were also assessed in vitro in cultured hepatocytes isolated from hypertensive (SHR, DOCA) and normotensive control (WKY, SPRD) rats. Our results suggest that a difference exists in the hepatic antioxidant status between rat strains, with GSH levels being lower (–15%) and lipid peroxidation rate higher (+30%) in WKY compared to SPRD rats. In hepatocyte cultures from WKY rats, both GSH content and catalase activity were lower (–30 and –70% respectively) compared to hepatocyte cultures from SPRD rats. This was associated with a 35% higher cytotoxicity of acetaminophen in cultured hepatocytes from WKY rats compared to that in hepatocytes from SPRD rats. Hypertension in DOCA rats (mmHg: 221 ± 9 vs. 138 ± 5 in control SPRD rats) was associated with decreases (about 30%) in both glutathione peroxidase (GSH-Px) and catalase activities, ex vivo in livers and in vitro in hepatocyte cultures. Hypertension in SHR (mmHg: 189 ± 7 vs. 130 ± 5 in control WKY rats) was also associated with decreases (about 50%) in GSH-Px activity, ex vivo in livers and in vitro in hepatocyte cultures but catalase activity was not modified. The IC₅₀ of acetaminophen was also lower in hepatocytes from hypertensive rats compared to respective controls, which could be related to the weakened antioxidant status in hepatocytes from hypertensive rats. Our data thus suggest that hepatocyte cultures are appropriated tools in which to assess hepatotoxicity and hepatoprotection in hypertension.     

In vitro propagation of taro,with spermine,arginine, and ornithine

In vitro growth and multiplication of taro [Colocasia esculenta var. antiquorum cv. Keladi Birah] was improved considerably, when primary shoot apices were cultured on two modifications of Linsmaier and Skoog [1965] medium, containing 5.5 mg 1^–1 naphthaleneacetic acid and 0.2 mg 1^–1 kinetin or 1.85 mg 1^–1 naphthaleneacetic acid and 2 mg 1^–1 kinetin and supplemented with 10^–4 or 10^–3 mol·1^–1 of polyamine spermine or either of the precursors of polyamine putrescine—arginine and ornithine. Plantlets were regenerated directly from primary shoot apices, axillary buds and protocorm-like bodies [PLB]. Frequency of plantlet regeneration, rate of development and growth in height of main plantlets were enhanced by the addition of arginine and ornithine to the media. Secondary plantlet formation from axillary buds and PLB were promoted by spermine and arginine respectively.     

Influence of ventilation closure, gelling agent and explant type on shoot bud proliferation and hyperhydricity in Scrophularia yoshimurae—A medicinal plant

Summary We report an improved procedure of in vitro propagation of Scrophularia yoshimurae—a medicinally important plant species indigenous to Taiwan. Induction of maximum shoot buds (22.75 per explant) was obtained with shoot tip explant cultured on Murashige and Skoog medium supplemented with 1.0mgl^−1 benzyladenine (BA) and 0.2mgl^−1 α-naphthaleneacetic acid and gelrite using dispense paper (DP) for ventilation closure of culture vessels. The type of gelling agents (agar and Gelrite) affected both quantity and quality of the shoots induced. Using aluminum foil for ventilation closure resulted in a higher number of hyperhydric shoots. Hyperhydricity was reduced by culturing shoots on a medium devoid of plant growth regulators in conjunction with the use of DP. Plantlet growth in vessels using DP was healthier and all plantlets survived after being transplanted to soil.     

Molecular phylogeny ofForsythia (Oleaceae) based on chloroplast DNA variation

Phylogenetic relationships of ten wild species and several cultivars ofForsythia were reconstructed based on the chloroplast (cp) DNA variation. A total of 216 cpDNA variants, 44 of which were potentially phylogenetically informative, was detected using 24 restriction endonucleases. Phylogenetic analysis usingFontanesia andAbeliophyllum as outgroups revealed four well defined species groups in the genus: 1)F. suspensa, 2)F. europaea — F. giraldiana, 3)F. ovata — F. japonica — F. viridissima, and 4)F. koreana — F. manshurica — F. saxatilis. The amount of support for each monophyletic group was evaluated by various methods including character number, decay analysis, parsimony bootstrapping, Neighbour-Joining (NJ) — bootstrapping, NJ-jackknifing, and the topology-dependent permutation tail probability (T-PTP) test. The data do not support the hybrid origin ofF. intermedia fromF. suspensa andF. viridissima. The disjunctly distributed European species,F. europaea, was identified as a sister species of the ChineseF. giraldiana and it was probably derived through recent long distance dispersal.     

Pollination ofDianthus gratianopolitanus (Caryophyllaceae)

Pollination ofDianthus gratianopolitanus was studied in a population of the Swiss Jura mountains. Pollinators of this plant species are reported here for the first time. The flowers were not only visited by butterflies as postulated in the literature, but also by diurnal hawkmoths (Macroglossum stellatarum) and by diurnal and nocturnal noctuid moths. — Nectar is sucrose-dominant, the sugar concentration is moderate but the amino acid concentration is high. Nectar characteristics correspond well with the syndrome ofLepidoptera-pollinated flowers. — Field observations and flower characters (colour, range of the calyx length) suggest thatDianthus gratianopolitanus is an intermediate species in the transition of butterfly to moth pollination. — Lack of reproductive success inDianthus gratianopolitanus can not be attributed to lack of suitable pollinators.     

Fünf neue Arten der GattungAnthemis (Compositae) aus Iraq und Afghanistan

Five new species ofAnthemis sect.Anthemis from the Flora Iranica region are described:A. gillettii (subsect.Anthemis) from NW. Iraq and adjacent Iran is allied toA. damascena.—A. kurdica (subsect.Anthemis) also grows in Iraqi Kurdistan.—A. hamrinensis (subsect.Rascheyana; akin toA. plebeia) is distributed in the Jabal Hamrin region at the extreme outer margin of the Zagros chains.—A. kandaharica (subsect.Anthemis) andA. freitagii (subsect.Rascheyana) are distributed in Afghanistan.

Anschrift des Herausgebers: Hofrat Univ.-Prof. Dr.Karl Heinz Rechinger, Beckgasse 22, A-1130 Wien, Österreich.     

The Leiognathus splendens complex (Perciformes: Leiognathidae) with the description of a new species, Leiognathus kupanensis Kimura and Peristiwady

Taxonomic analysis of a group of morphologically similar ponyfishes (Perciformes: Leiognathidae) establishes the Leiognathus splendens complex comprising four valid species: L. jonesi James, 1971, widely distributed in the Indo-West Pacific, from Mauritius to Papua New Guinea, north to Hainan I. (China), and south to Brisbane, Australia; L. kupanensis sp. nov., currently known only from Kupang, Timor, Indonesia; L. rapsoni Munro, 1964, currently known only from India, Indonesia, and Papua New Guinea, and L. splendens Cuvier, 1829, widely distributed in the eastern Indian and western Pacific oceans, from India to Papua New Guinea, and from southern Japan to northern Australia. The L. splendens complex can be defined by the following combination of characters: body depth 42–60% of standard length; mouth protruding downward; slender, minute teeth uniserially on jaws; lower margin of orbit above the horizontal through the gape when mouth closed; breast almost completely scaled; lateral line complete, and a dark blotch on top of spinous dorsal fin. Diagnostic characters of the members are as follows: L. jonesi—anterior dorsolateral body surface with a semicircular naked area on nape, and a paler dark blotch on spinous dorsal fin; L. kupanensis—anterior dorsolateral body surface widely naked; L. rapsoni—cheek scaled; L. splendens—anterior dorsolateral body surface completely scaled and a jet black blotch on spinous dorsal fin.     

Recombination During In Vitro Evolution

Recombination, the swapping of large portions of genetic information between and among parental genotypes, can be applied to in vitro evolution experiments on functional nucleic acids. Both homologous and heterologous recombination can be achieved using standard laboratory techniques. In many cases, recombination can allow for the discovery of a ribozyme or DNAzyme phenotype that would not likely be encountered by reliance on point mutations alone. In addition, recombination can often aid in the discovery of global optima in sequence space and/or lessen the number of generations it would take to reach optima. Recombination is most efficiently used in combination with point mutations and applied after the first couple of rounds of selection but before high-fitness genotypes dominate the selection. The “recombination zone” describes that region of sequence space—defined by the residues that will ultimately participate in the function of the winning nucleic acid(s)—where recombination is expected to be the most beneficial in the search for high-fitness genotypes.[Reviewing Editor: Martin Kreitman]Author order determined by a single Bernoulli trial as implemented by RPS.     

Genetic mapping,distribution, and properties of an aconitase isozyme in Anopheles albimanus (Diptera:Culicidae)

Electrophoretic analysis of the developmental stages and tissues of Anopheles albimanus showed that qualitatively similar allozymes of aconitase (Acon-2) occur at all stages, and the enzyme is widespread in every larval and adult tissues. Relative heat stabilities of the allozymes were investigated by electrophoresis of heated aqueous extracts and by heating the enzyme in situ in acrylamide gels after electrophoretic separation in Tris-citrate and Tris-maleate buffer systems. The pupal aconitase in the crude extract is more stable to heat than the larval and adult enzyme. The presence of citrate ions in the gel increased the stability of aconitase to heat. Studies of substrate specificities indicated that cis-aconitic acid is the best substrate but citric acid can also serve as a substrate. Zymograms developed with isocitric acid as a substrate showed no aconitase electromorphs and produced only isocitrate dehydrogenase bands. Aconitase has a pH optimum of 8.0 and this enzyme is completely inhibited if treated in situ with ethylenediaminetetra-acetic acid (EDTA), p-chloromercuribenzoate (PCMB), and urea at concentrations higher than 5mm, 5×10^–5 m, and 2 m, respectively. Acon-2¹⁰⁰ and Acon-2¹⁰⁵ do not respond differently to the above treatments. Genetic crosses involving a holandric translocation, pericentric inversions, visible mutants, and allozyme markers were analyzed to map the aconitase (Acon-2) locus on the left arm of chromosome 3. The gene sequence (and map distances) on 3L is centromere—esterase-8 (Est-8)—2—esterase-4 (Est-4)—25—esterase-2 (Est-2)—9—Acon-2—5—phosphoglucomutase (Pgm)—7—esterase-6 (Est-6).     

The interaction of phagocytes and the large-sized parasite Cryptococcus neoformans: Cytochemical and ultrastructural study

Summary The yeast Cryptococcus neoformans may develop under certain conditions a large polysaccharide capsule 50–100 M in diameter and therefore cannot be phagocytosed by either polymorphonuclear cells (PMN's) or mononuclear phagocytes (MN's). The cellular defense mechanism — in various animals — against the yeast is composed by formation of ringlike structure of PMN's or MN's cells which surround the C. neoformans. Ring structures develop either in vivo or in vitro in tissue culture; destruction of the yeast occurs within 36–72 hours.Several hydrolases, such as acid phosphatase, -glucuronidase and non-specific esterase were found to be released from the phagocytic cells into the enclosed yeast. Considerable reduction of NBT used as a marker for oxidative activity was observed in MN rings at contact regions of the MN cells and the yeast. Electron microscopic studies indicate that the phagocytic cells in the ring structure have many pseudopodes penetrating into the polysaccharide capsule of the yeast. Disintegration of the capsule was observed as well as phagocytosis of its material. A possible analogy between normal phagocytosis of small-sized bodies and the ring structure obtained when large bodies are involved is discussed.     

Zooplankton and their relationships with water quality and fisheries

Zooplankton population structure in Rutland Water changed over the first five years of the reservoir's existence. Daphnia pulex, initially dominant was replaced by D. hyalina in late 1975 and since 1979 this latter cladoceran has coexisted for part of each year with Bosmina longirostris. Population fluctuations of all the main crustacean zooplankton — D. hyalina, Cyclops spp. and Diaptomus gracilis — were erratic in the first three years (1975–1977) but have since become more regular. The relationships of the zooplankton with their potential algal food supply and with their potential predators, the fish population, are discussed.     

Anti-<Emphasis Type="Italic">Helicobacter pylori</Emphasis> substances from endophytic fungal cultures

The human pathogenic bacterium Helicobacter pylori has been ascertained to be an aetiological agent for chronic active gastritis and a significant determinant in peptic and duodenal ulcer diseases. Endophytic metabolites are being recognized as a versatile arsenal of antimicrobial agents, since some endophytes have been shown to possess superior biosynthetic capabilities owing to their presumable gene recombination with the host, while residing and reproducing inside the healthy plant tissues. A total of 32 endophytic fungi isolated from the medicinal herb Cynodon dactylon(Poaceae) were grown in in vitroculture, and the ethyl acetate extracts of the cultures were examined in vitro for the anti-H. pylori activity. As a result, a total of 16 endophyte culture extracts were identified as having potent anti-H. pyloriactivities. Subsequently, a detailed bioassay-guided fractionation of the extract of the most active endophyte (strain number: CY725) identified as Aspergillussp., was performed to afford eventually four anti-H. pylori secondary metabolites. The four isolated compounds were identified through a combination of spectral and chemical methods (IR, MS, ¹H- and ¹³C-NMR) to be helvolic acid, monomethylsulochrin, ergosterol and 3β-hydroxy-5α,8α-epidioxy- ergosta-6,22-diene with corresponding MICs of 8.0, 10.0, 20.0 and 30.0 μg/ml, respectively. The MIC of ampicillin co-assayed as a reference drug against H. pylori was 2.0 μg/ml. Furthermore, preliminary examination of the antimicrobial spectrum of helvolic acid, the most active anti-H. pylori metabolite characterized from the endophyte culture, showed that it was inhibitory to the growth of Sarcina lutea, Staphylococcus aureusand Candida albicans with MICs of 15.0, 20.0 and 30.0 μg/ml, respectively.     

In vitro spore formation and completion of the asexual life cycle of Neozygites parvispora, an obligate biotrophic pathogen of thrips

Capilliconidia, the asexual secondary spores of Neozygites parvispora (Zygomycetes, Entomophthorales) were produced in vitro either by entrapment of vegetative cells (hyphal bodies) in alginate pellets or after plating them onto water agar. Cultivation of the fungus for 3 days in a medium lacking hemolymph increased spore production 30 to 40-fold, and about 10% of the cells produced capilliconidia. The in vitro produced capilliconidia were infectious to Thrips tabaci and the fungus was reisolated from infected insects, thus completing its asexual life cycle under laboratory conditions. A decrease in capilliconidia production and a modification of the number of nuclei per spore were observed for isolates cultivated in vitro for more than 2 months, but subsequent host passages restored and increased sporulation efficiency without influencing the number of nuclei. Fungal cultures were stored at —80 °C for up to 7 months, and the capability to sporulate and infect T. tabaci was preserved. A bioassay procedure for infecting T. tabaci with N. parvispora is described, the first mycosed insects dying usually after 8 d of incubation.