Difference in the response to PIF/activin between animal caps excised from mid- or late blastula stages of Xenopus laevis.

Animal caps from Xenopus embryos at Stage 7/8 cultured in salt solution, were capable of elongating, and formed various embryonic tissues including axial mesoderm, nervous tissues and pigmented retina. In contrast, animal caps from Stage 9 only developed into permanent blastulae. Following exposure to PIF/activin, however, such animal caps displayed morphogenetic movements. They formed tube-shaped embryoids that frequently had one or more tails but no head. We conclude that animal caps from Stage 9 produce more reliable results than those from Stage 7/8 because the latter are most likely contaminated with mesodermal cells.     

ω10-Lipoxygenase products of α-linolenic acid are esterified to phospholipids inHydra vulgaris

We have recently reported the occurrence of 9(R)-hydroxy-, 9(R)-hydroperoxy- and 9-keto-octadeca-10E,12Z,15Z-trienoic acids (9-HOTrE, 9-HPOTrE and 9-KOTrE) inHydra vulgaris, and their biosynthesis from -linolenic acid (-LA) through the action of an enantioselective 10(R)-lipoxygenase (10-LO). Here we describe the finding of these -LA metabolites as esters to the 2-position of phosphatidylcholine, phosphatidylethanolamine and, in trace amounts, phosphatidylinositol. Small amounts of a compound co-eluting with an authentic standard of 9(R)-hydroxy-octadeca-10E,12Z-dienoic acid, a metabolite potentially derived from the action of 10-LO on linoleic acid, were also found esterified with phospholipids. Since direct peroxidation of membrane lipids has been described, experiments were aimed at establishing whether -LA metabolite-containing phospholipids could originate, inH. vulgaris, from either spontaneous or 10-LO-catalyzed oxidation of phospholipid-bound -LA. Incubation of either unlabelled or radiolabelled PUFA-containing phosphoglycerides withH. vulgaris 10-LO did not result in their peroxidation. This suggests that -LA and LA metabolites are incorporated into glycerophospholipids after their formation by 10-LO, and that, as in mamals, membrane phospholipids may serve as a reservoir for these bioactive compounds. This is the first example in an invertebrate species of lipoxygenase products esterified to phosphoglycerides.     

Über das Vorkommen und die Natur der Cholinesterase der Schlangengifte

Summary An enzyme that hydrolyzes acetylcholine is present in the dried venoms of 19 species of theColubridae (9 genera), but not in the venoms of more than 20 species of theViperidae (7 genera). The enzyme behaves like the e-Cholinesterase of the mammalian tissues.     

Morphological and histochemical demonstration of a glycocalyx on the cell surface ofChattonella antiqua,a ‘naked flagellate’

Summary Electron microscopy demonstrated the presence of glycocalyx on the cell surface ofChattonella antiqua, which was previously believed to be naked. Histochemical analysis of this structure indicates that the glycocalyx consists of at least two different types of acidic complex carbohydrates, sulfated and nonsulfated, together with a neural carbohydrate-protein complex with 1,2-glycol groups and -D-mannosyl and -D-glucosyl residues.     

Kondensationsprodukte von Oxyketonen und Aminoketonen mit 2,4,5-Triamino-6-oxy-pyrimidin

Summary By condensing 2:4:5-triamino-6-hydroxy-pyrimidine with dihydroxyacetone (diacetate), diaminoacetone or acetone-1,3-di (p-formylaminobenzoic acid) not the expected 8- or 9-oxymethyl resp. -aminomethyl-pteridines but 8-or 9-methyl-pteridines were obtained. With p-tolyl-d-isoglucosamine not a tetrahydroxybutyl-pteridine but a trihydroxybutyl-pteridine was formed. For an explanation of these results it is supposed that from the dihydro-pteridines formed at first by intramolecular splitting off of H₂O or R·NH₂ aromatization takes place.     

The toxicity of twoBacillus thuringiensis δ-endotoxins to gypsy moth larvae is inversely related to the affinity of binding sites on midgut brush border membranes for the toxins

Summary The-endotoxin fromBacillus thuringiensis subspecieskurstaki strain HD1-9 is almost 400 times more potent than the-endotoxin from strain HD-73 as a gypsy moth larvicide. The two-endotoxins compete for a high-affinity binding site on the brush border membrane of larval gypsy moth midguts. The affinity for the-endotoxin from strain HD-73 is much greater than the affinity for the-endotoxin from strain HD1-9.     

A newTrichoplusia ni antennal receptor neuron that responds to attomolar concentrations of a minor pheromone component

Summary A newly discovered third class of sensillum trichodea on the antenna ofTrichoplusia ni contains an olfactory receptor neuron that responds to (Z)-9-tetradecen-1-ol acetate at 1×10^–18 M. The threshold of this neuron is 100–1000 times lower than the thresholds of two previously described pheromone-sensitive neurons that detect (Z)-7-dodecen-1-ol acetate and (Z)-7-tetradecen-1-ol acetate. The sensitivity and selectivity of this receptor neuron is evidence that (Z)-9-tetradecen-1-ol acetate may be important for sexual behavior.     

Determination of diel periodicity of sex pheromone release in three species of Lepidoptera by ‘closed-loop-stripping’

Summary By means of closed-loop-stripping and subsequent GC analyses the diel periodicity of release of (Z)-11-hexadecenyl acetate, (E)-8-dodecenyl acetate, and (Z)-9-tetradecenyl acetate, the main constituents of the respective sex pheromone blends ofMamestra brassicae, Cryptophlebia leucotreta andSpodoptera sunia females, was determined.Pheromones, 64. For the 63rd contribution we have taken from: Szöcs, G., Toth, M., Bestmann, H. J., Vostrowsky, O., Heath, R. R., and Tumlinson, J. H., Z. Naturforsch.42c (1987) 165; Pheromones, 62: Bestmann et al.¹³.     

γ-Glutamyl-transpeptidase in lymphatic tissues ofMastomys natalensis during an infection withAcanthocheilonema viteae

Summary DuringAcanthocheilonema viteae infection, the specific activity of -glutamyltranspeptidase (-GT) increased in peritoneal exudate cells and bone marrow and decreased in lymphnodes ofMastomys natalensis throughout the course of infection. However, though there was an increase in specific activity of -GT in thymus and spleen during the prepatent phase ofA. viteae infection, the level either returned to normal or decreased during the latent phase of infection. A close correlation was observed between the host's immune status duringA. viteae infection and the level of -GT in lymphoid tissues.Communication No. 4535 from Central Drug Research Institute, Lucknow.     

Partial sequence of the gene for a serine protease from a halophilic archaeumhaloferax mediterranei R4, and nucleotide sequences of 16S rRNA encoding genes from several halophilic archaea

A part of the gene coding for a halophilic serine protease from a halophilic archaeumHaloferax mediterranei R4 was amplified by PCR and its 672 nucleotide sequence was determined. Tentative translation to the amino acid sequence suggested that the enzyme was quite similar to halolysin produced by another halophilic archaeum strain 172P1. Nucleotide sequences of 16S rRNA encoding genes from 9 halophilic archaea were determined. Alignment of 19 sequences known so far showed that there are more than 20 positions carrying bases or deletions specific for each halobacterial genus:Halobacterium, Haloarcula, Haloferax, andHalococcus.     

Multiple sex-linked reciprocal translocations in a termite from Jamaica

Summary Males of the termiteIncisitermes schwarzi from Jamaica have a diploid chromosome number of 32. In male meiosis there are 7 bivalents, and a ring of 18 chromosomes equivalent to sex chromosomes, 9 X's and 9 Y's. This is the largest reciprocal translocation complex so far described for any plant or animal species.This work was supported by a grant from the National Science Foundation, No. DEB 78-02042.     

A single tryptophan residue of endomannosidase is crucial for Golgi localization and <Emphasis Type="Italic">in vivo</Emphasis> activity

Golgi-endomannosidase provides an alternate glucosidase-independent pathway of glucose trimming. Activity for endomannosidase is detectable in various tissues and cell lines but not in CHO cells. Cloning of CHO cell endomannosidase revealed that the highly conserved Trp188 and Arg177 of vertebrate endomannosidase were both substituted by Cys. The Trp188Cys substitution was functionally important since it alone resulted in endoplasmic reticulum (ER) mislocalization of endomannosidase and caused the greatly reduced in vivo activity. These effects could be reversed in cells with a back-engineered Cys188Trp CHO cell endomannosidase, in particular N-glycans of α1-antitrypsin became fully processed. The intramolecular disulfide bridge of CHO cell endomannosidase formed with the additional Cys188 was not solely responsible for the reduced enzyme activity since endomannosidase with engineered Cys188Ala or Ser substitutions did not restore enzyme activity and was ER mislocalized. Thus, the conserved Trp188 residue in endomannosidases is of critical importance for correct subcellular localization and in vivo activity of the enzyme. Received 7 May 2007; received after revision 31 May 2007; accepted 11 June 2007     

Sexual behavior without adult morphogenesis inLocusta migratoria

Summary Injection of azadirachtin into young Vth (=last) instarLocusta hoppers inhibits molt and a considerable portion of the animals survice for more than 40 days as over-aged nymphs; in contrast, the duration of the Vth instar is 8–10 days in normal controls. Males of over-aged nymphs exhibit adult sexual behavior, and injection of juvenile hormone intensifies this behavior. The results demonstrate that the terminal molt leading to morphogenetic adult differentiation is not necessary for an adult behavioral pattern to develop, and/or to become overt, in a hemimetabolous insect.We thank Prof. H. Rembold for a generous gift of azadirachtin and Mr Y. Toren for keeping the locust culture.     

A cyanoglucoside stored by aSedum-feeding Apollo butterfly,Parnassius phoebus

A bitter tasting cyanoglucoside, sarmentosin, was isolated from an aposematic Apollo butterfly,Parnassius phoebus, and from its plant-host,Sedum stenopetalum. The content of sarmentosin in the body tissues was as high as 500 g/insect, suggesting a defensive role for this substance; a high concentration was detected in the wings. Sarmentosin was also present in the eggs.     

Horizontal gene transfer from Eukarya to Bacteria and domain shuffling: the α-amylase model

-Amylases are present in all kingdoms of the living world. Despite strong conservation of the tertiary structure, only a few amino acids are conserved in interkingdom comparisons. Animal -amylases are characterized by several typical motifs and biochemical properties. A few cases of such -amylases have been previously reported in some eubacterial species. We screened the bacterial genomes available in the sequence databases for new occurrences of animal-like -amylases. Three novel cases were found, which belong to unrelated bacterial phyla: Chloroflexus aurantiacus, Microbulbifer degradans, and Thermobifida fusca. All the animal-like -amylases in Bacteria probably result from repeated horizontal gene transfer from animals. The M. degradans genome also contains bacterial-type and plant-type -amylases in addition to the animal-type one. Thus, this species exhibits -amylases of animal, plant, and bacterial origins. Moreover, the similarities in the extra C-terminal domains (different from both the -amylase domain C and the starch-binding domain), when present, also suggest interkingdom as well as intragenomic shuffling.Received 17 October 2003; accepted 6 November 2003     

Identification of mucondialdehyde as a novel stress metabolite

In a survey of antifungal stress compounds induced by cupric chloride we found that leaves ofChenopodium album exuded a highly fungitoxic metabolite mucondialdehyde (trans-2,trans-4-hexadienedial), which was associated with 13-oxo-9,11-tridecadienoic acids (cis-9,trans-11 andtrans-9,trans-11 isomers) presumably resulting from -scission of 13-hydroperoxy-octadecadi(tri)enoic acid. The biogenesis and role as a general defensive agent in plants are briefly discussed.     

Effect of actinomycin D onTrypanosoma cruzi

Summary Viable metacyclic forms ofT. cruzi, Y strain, treated with an adequate dose of actinomycin D (50 g Act-D/ml/10⁷ parasites/ml for 72 h at 28° C) showed the following properties: 1) they lost their ability to replicate in culture medium, in blood and in tissues of normal mice and were no longer able to incorporate tritiated thymidine; 2) they could no penetrate into Vero cells and could not replicate inside normal macrophages; 3) they retained their immunogenicity and the ability to protect mice against a virulent infection; 4) they did not induce histological lesions as described in chronic experimental Chagas' disease.     

Sex pheromone of the pine sawflyDiprion pini (Hymenoptera: Diprionidae): Chemical identification,synthesis and biological activity

The main component of the sex pheromone secretion of femaleDiprion pini L. (Hymenoptera: Diprionidae) from insects collected both in Finland and in France has been identified as athreo-3,7-dimethyl-2-tridecanol (8 ng per female) stereoisomer by GC-MS and synthesis. The secretion also contains lower and higher homologues in small amounts (1–4% of the main component). Combined gas chromatographic-electroantennographic detection showed activity in both natural and esterified extracts (acetates and propionates); the esters of the main component gave the largest responses. The acetates and propionates of the eight stereoisomers of 3,7-dimethyl-2-tridecanol were synthesized from enantiomerically highly enriched (>99% ee) building blocks. The stereochemistry of the main component was established to be (2S,3R,7R)-3,7-dimethyl-2-tridecanol by GC analysis of the natural material. It was purified by liquid chromatography prior to the GC analysis of both its pentafluorobenzoates and its isopropylcarbamates on a non-chiral polar column (ECD) and a chiral column (NPD), respectively. Field tests demonstrated that both the acetate and propionate of the main component (100 g of each applied on cotton roll dispensers) were active in attracting males, with or without the presence of several of the minor compounds. Experiments with smaller amounts of the acetate and the propionate (1 g in France and 50 g in Finland) demonstrated that the propionate was more active than the acetate, and that it also caught more males than a blend of the two compounds.     

Ein Töne erzeugender Fisch im Neapler Aquarium

Summary During a stay at the Naples Zoological Station in July the production of a knocking sound byCorvina nigra (Sciaenidae) was observed. Each sound signal consisted of a short series of knocks (ranging from 2 to 7) which followed each other at a rate of 8 per second. The sound-producing animal, probably a male, knocked every time when it was driving away another individual of the same species. All this occurred most frequently in the evening during twilight.     

Role of <Emphasis Type="Italic">N</Emphasis>-linked polymannose oligosaccharides in targeting glycoproteins for endoplasmic reticulum-associated degradation

Misfolded or incompletely assembled multisubunit glycoproteins undergo endoplasmic reticulum-associated degradation (ERAD) regulated in large measure by their N-linked polymannose oligosaccharides. In this quality control system lectin interaction with Glc₃Man₉GlcNAc₂ glycans after trimming with endoplasmic reticulum (ER) -glucosidases and -mannosidases sorts out persistently unfolded glycoproteins for N-deglycosylation and proteolytic degradation. Monoglucosylated (Glc₁Man₉GlcNAc₂) glycoproteins take part in the calnexin/calreticulin glucosylation-deglucosylation cycle, while the Man₈GlcNAc₂ isomer B product of ER mannosidase I interacts with EDEM. Proteasomal degradation requires retrotranslocation into the cytosol through a Sec61 channel and deglycosylation by peptide: N-glycosidase (PNGase); in alternate models both PNGase and proteasomes may be either free in the cytosol or ER membrane-imbedded/attached. Numerous proteins appear to undergo nonproteasomal degradation in which deglycosylation and proteolysis take place in the ER lumen. The released free oligosaccharides (OS) are transported to the cytosol as OS-GlcNAc₂ along with similar components produced by the hydrolytic action of the oligosaccharyltransferase, where they together with OS from the proteasomal pathway are trimmed to Man₅GlcNAc₁ by the action of cytosolic endo--N-acetylglucosaminidase and -mannosidase before entering the lysosomes. Some misfolded glycoproteins can recycle between the ER, intermediate and Golgi compartments, where they are further processed before ERAD. Moreover, properly folded glycoproteins with mannose-trimmed glycans can be deglucosylated in the Golgi by endomannosidase, thereby releasing calreticulin and permitting formation of complex OS. A number of regulatory controls have been described, including the glucosidase-glucosyltransferase shuttle, which controls the level of Glc₃Man₉GlcNAc₂-P-P-Dol, and the unfolded protein response, which enhances synthesis of components of the quality control system.Received 26 January 2004; accepted 25 February 2004