Molecular evidence for species level divergence in African Nile Crocodiles Crocodylus niloticus (Laurenti, 1786)

Relationships of the newly discovered dwarf crocodiles from Mauritania were inferred from mitochondrial 12S sequences. Specimens from 13 different Crocodylus niloticus populations (from East Africa, West Africa and Madagascar) were compared. Additional representatives of the genus Crocodylus (one from Africa and one from Australia), the African genus Osteolaemus and the South American alligatorid Paleosuchus palpebrosus (as outgroup) were included in the analysis. Maximum-likelihood and Bayesian analyses yielded relationships that were strikingly different from currently prevailing phylogenetic hypotheses. Both analyses consistently revealed two groups, one consisting of the monophyletic West- and Central African populations and the other of a paraphyletic group containing the East African and Madagascan populations. High genetic divergence between those groups indicates separation on the species level. Furthermore ‘C’ cataphractus is clearly shown not to be a member of the genus Crocodylus. The resulting nomenclatural changes are discussed. To cite this article: A. Schmitz et al., C. R. Palevol 2 (2003).     

Use of PCR and partial sequencing of the large-subunit rRNA gene to identify Alexandrium catenella (Dinophyceae) from the South of Chile

A fragment of the large-subunit ribosomal DNA gene (LSU rDNA) from Chilean Alexandrium catenella clones isolated from two different geographic regions (XI and XII) was amplified by PCR and the products cloned and sequenced. Based on the analysis of the PCR products it is possible to distinguish two strains of A. catenella, denominated strain type 1 (a single PCR product band) and strain type 2 (two PCR product bands). These two strains proliferate in both, the XI and XII regions. Only in the XI region, there is evidence that they bloom simultaneously. The LSU rDNA sequence analysis indicate that the Chilean A. catenella isolated clones are more related to the North American ribotype-Western subribotype.     

白花地胆草的抗菌活性成分研究

从白花地胆草(Elephantopus tomentosus Linn.)全草的乙醇提取物中分离得到9个化合物,通过波谱分析,鉴定其结构分别为:表木栓醇(1)、羽扇豆醇(2)、6-deoxyisojacreubin(3)、桦木酸(4)、熊果酸(5)、阿魏酸(6)、3-甲酰吲哚(7)、半夏酸(8)和30-醛基羽扇豆醇(9)。所有化合物均为首次从白花地胆草中分离得到。用滤纸片琼脂扩散法测定上述化合物的抗菌活性,结果表明,化合物6和7对金黄色葡萄球菌的生长有抑制作用,化合物6和8对烟草青枯病菌的生长有抑制作用。     

Importance of Nutrient Competition and Allelopathic Effects in Suppression of the Green Alga Scenedesmus obliquus by the Macrophytes Chara, Elodea and Myriophyllum

Possible allelopathic effects of substances released from the macrophytes Chara globularis, Elodea canadensis, Myriophyllum spicatum on the common green alga Scenedesmus obliquus were tested in the laboratory with plastic plants and untreated medium as controls. A two-phase approach was used in which first the effects of physical presence of plants was studied (phase I) followed by the effects of plant culture filtrates (phase II). In the presence of plastic plants growth was reduced only marginally, but strong growth inhibition of Scenedesmus occurred in the physical presence of all macrophytes. In contrast, filtrates from Chara had no growth inhibitory effect on Scenedesmus. Myriophyllum filtrate reduced particle-based growth rate by 7% compared to filtration controls, while Elodea culture filtrate reduced volume-based growth by 12%, chlorophyll-based growth by 28% and particle-based growth by 15%. Photosystem II-efficiency of Scenedesmus was reduced in all three macrophyte treatments in phase I, but not in filtrates from macrophyte cultures (phase II). Thus, while enzyme activity or other physiological aspects may have been affected, the current study yielded no proof for allelopathically active compounds being directed at photosynthesis. Mean particle volume (MPV) of Scenedesmus was not influenced by macrophyte exudates and cultures remained dominated by unicells. The strong growth inhibitory effects found for Scenedesmus in the physical presence of macrophytes, but not in plastic controls, and no or weaker response in nutrient-enriched filtrates, suggest nutrient competition was a more powerful driving factor than allelochemicals. However, the experimental design does not exclude disappearance of allelochemicals during the filtration process.     

Proteome analysis of the medicinal plant <Emphasis Type="Italic">Catharanthus roseus</Emphasis>

A proteomic approach is undertaken aiming at the identification of novel proteins involved in the alkaloid biosynthesis of Catharanthus roseus. The C. roseus cell suspension culture A11 accumulates the terpenoid indole alkaloids strictosidine, ajmalicine and vindolinine. Cells were grown for 21 days, and alkaloid accumulation was monitored during this period. After a rapid increase between day 3 and day 6, the alkaloid content reached a maximum on day 16. Systematic analysis of the proteome was performed by two-dimensional polyacrylamide gel electrophoresis. After day 3, the proteome started to change with an increasing number of protein spots. On day 13, the proteome changed back to roughly the same as at the start of the growth cycle. 88 protein spots were selected for identification by mass spectrometry (MALDI-MS/MS). Of these, 58 were identified, including two isoforms of strictosidine synthase (EC 4.3.3.2), which catalyzes the formation of strictosidine in the alkaloid biosynthesis; tryptophan synthase (EC 4.1.1.28), which is needed for the supply of the alkaloid precursor tryptamine; 12-oxophytodienoate reductase, which is indirectly involved in the alkaloid biosynthesis as it catalyzes the last step in the biosynthesis of the regulator jasmonic acid. Unique sequences were found, which may also relate to unidentified biosynthetic proteins.     

Transformation of opium poppy (<Emphasis Type="Italic">Papaver somniferum</Emphasis>L.) with antisense berberine bridge enzyme gene (<Emphasis Type="Italic">anti-bbe</Emphasis>) via somatic embryogenesis results in an altered ratio of alkaloids in latex but not in roots

The berberine bridge enzyme cDNA bbe from Papaver somniferumL. was transformed in antisense orientation into seedling explants of the industrial elite line C048-6-14-64. In this way, 84 phenotypically normal T₀ plants derived from embryogenic callus cultures were produced. The selfed progeny of these 84 plants yielded several T₁ plants with an altered alkaloid profile. One of these plants T₁-47, and its siblings T₂-1.2 and T₂-1.5 are the subject of the present work. The transformation of these plants was evaluated by PCR, and northern and Southern hybridisation. The transgenic plants contained one additional copy of the transgene. The alkaloid content in latex and roots was determined with HPLC and LC-MS. We observed an increased concentration of several pathway intermediates from all biosynthetic branches, e.g., reticuline, laudanine, laudanosine, dehydroreticuline, salutaridine and (S)-scoulerine. The transformation altered the ratio of morphinan and tetrahydrobenzylisoquinoline alkaloids in latex but not the benzophenanthridine alkaloids in roots. The altered alkaloid profile is heritable at least to the T₂ generation. These results are the first example of metabolic engineering of the alkaloid pathways in opium poppy and, to our knowledge, the first time that an alkaloid biosynthetic gene has been transformed into the native species, followed by regeneration into a mature plant to enable analyses of the effect of the transgene on metabolism over several generations.     

Phylogeny of cardinalfishes (Teleostei: Gobiiformes: Apogonidae) and the evolution of visceral bioluminescence

The cardinalfishes (Apogonidae) are a diverse clade of small, mostly reef-dwelling fishes, for which a variety of morphological data have not yielded a consistent phylogeny. We use DNA sequence to hypothesize phylogenetic relationships within Apogonidae and among apogonids and other acanthomorph families, to examine patterns of evolution including the distribution of a visceral bioluminescence system. In conformance with previous studies, Apogonidae is placed in a clade with Pempheridae, Kurtidae, Leiognathidae, and Gobioidei. The apogonid genus Pseudamia is recovered outside the remainder of the family, not as sister to the superficially similar genus Gymnapogon. Species sampled from the Caribbean and Western Atlantic (Phaeoptyx, Astrapogon, and some Apogon species) form a clade, as do the larger-bodied Glossamia and Cheilodipterus. Incidence of visceral bioluminescence is found scattered throughout the phylogeny, independently for each group in which it is present. Examination of the fine structure of the visceral bioluminescence system through histology shows that light organs exhibit a range of morphologies, with some composed of complex masses of tubules (Siphamia, Pempheris, Parapriacanthus) and others lacking tubules but containing chambers formed by folds of the visceral epithelium (Acropoma, Archamia, Jaydia, and Rhabdamia). Light organs in Siphamia, Acropoma, Pempheris and Parapriacanthus are distinct from but connected to the gut; those in Archamia, Jaydia, and Rhabdamia are simply portions of the intestinal tract, and are little differentiated from the surrounding tissues. The presence or absence of symbiotic luminescent bacteria does not correlate with light organ structure; the tubular light organs of Siphamia and chambered tubes of Acropoma house bacteria, those in Pempheridae and the other Apogonidae do not.     

Kinetic modelling reveals current limitations in the production of ethanol from xylose by recombinant Saccharomyces cerevisiae

Saccharomyces cerevisiae lacks the ability to ferment the pentose sugar xylose that is the second most abundant sugar in nature. Therefore two different xylose catabolic pathways have been heterologously expressed in S. cerevisiae. Whereas the xylose reductase (XR)-xylitol dehydrogenase (XDH) pathway leads to the production of the by-product xylitol, the xylose isomerase (XI) pathway results in significantly lower xylose consumption. In this study, kinetic models including the reactions ranging from xylose transport into the cell to the phosphorylation of xylulose to xylulose 5-P were constructed. They were used as prediction tools for the identification of putative targets for the improvement of xylose utilization in S. cerevisiae strains engineered for higher level of the non-oxidative pentose phosphate pathway (PPP) enzymes, higher xylulokinase and inactivated GRE3 gene encoding an endogenous NADPH-dependent aldose reductase. For both pathways, the in silico analyses identified a need for even higher xylulokinase (XK) activity. In a XR-XDH strain expressing an integrated copy of the Escherichia coli XK encoding gene xylB about a six-fold reduction of xylitol formation was confirmed under anaerobic conditions. Similarly overexpression of the xylB gene in a XI strain increased the aerobic growth rate on xylose by 21%. In contrast to the in silico predictions, the aerobic growth also increased 24% when the xylose transporter gene GXF1 from Candida intermedia was overexpressed together with xylB in the XI strain. Under anaerobic conditions, the XI strains overexpressing xylB gene and the combination of xylB and GFX1 genes consumed 27% and 37% more xylose than the control strain.     

Phytochemical differentiation of Galanthus nivalis and Galanthus elwesii (Amaryllidaceae): A case study

The alkaloid patterns of two occasionally sympatric Galanthus nivalis and Galanthus elwesii populations were studied by GC/MS. Thirty-seven alkaloids were detected, 25 for G. nivalis and 17 for G. elwesii. Only five alkaloids were found to occur in both species. The populations of Galanthus differed in their alkaloid biosynthetic pathways. Thus, the alkaloid pattern of G. nivalis was dominated by compounds coming from a para–para′ oxidative coupling of O-methylnorbelladine. The predominant alkaloids in the roots of this species were found to belong to the lycorine and tazettine structural types; bulbs were dominated by tazettine, leaves by lycorine and flowers by haemanthamine type alkaloids. In contrast, the alkaloid pattern of G. elwesii was dominated mainly by compounds coming from an ortho–para′ oxidative coupling. The predominant alkaloids in G. elwesii roots, bulbs and leaves were those of homolycorine type, whereas the flowers accumulated mainly tyramine type compounds. The chemotaxonomical value of the alkaloids found in the studied species is discussed.     

Identification of Prosopis juliflora and Prosopis pallida Accessions Using Molecular Markers

There has been much taxonomic confusion over the identification of Prosopis species, especially where introduced. Prosopis juliflora is the most widespread species in the arid and semi-arid tropics, although it has been confused with other species, particularly the closely related Prosopis pallida. In this study, RAPDs markers were used for the first time to distinguish between these species. Eighteen primers were used in amplification reactions, which yielded an average of 120 bands per accession. A dendrogram showing genetic similarities among accessions was constructed using UPGMA cluster analysis and the Nei and Li similarity coefficient. The genetic similarity observed between P. juliflora and P. pallida is similar to the value in sympatric Prosopis species in North America, and reconsideration of the series rank in section Algarobia is suggested. Species-specific markers confirmed that material in Burkina Faso is P. juliflora, but suggested that material collected in Brazil, Cape Verde and Senegal is P. pallida, whereas this has previously been identified as P. juliflora.     

Natural establishment of a parasitoid complex on Bactrocera latifrons (Diptera: Tephritidae) in Hawaii

Bactrocera latifrons (Hendel) (Diptera: Tephritidae) is the most recent of four tephritid fruit fly species accidentally introduced into Hawaii. Although parasitoids have been released against other tephritid fruit fly species and have shown partial success in Hawaii, no parasitoids were released until 2004 to suppress populations of B. latifrons. The present study was conducted to document the parasitoid complex that has naturally established against B. latifrons in Hawaii and to assess whether there is a need for improving the biological control of this species. Based on ripe turkeyberry (Solanum torvum Sw) fruit collections over three consecutive years B. latifrons was the dominant tephritid fruit fly infestating turkeyberry at all four sites surveyed, across three major islands in Hawaii. The overall percentage parasitism of B. latifrons ranged from a low of 0.8% (Hana, Maui) to a high of 8.8% (Kahaluu, Oahu). Five primary parasitoid species were recovered from individually held B. latifrons puparia: Fopius arisanus (Sonan), Psyttalia incisi (Silvestri), Diachasmimorpha longicaudata (Ashmead), D. tryoni (Cameron), and Tetrastichus giffardianus Silvestri. F. arisanus was the predominant parasitoid at three of the four sites. Low levels of parasitism suggest that there is a need to improve biological control of B. latifrons, to minimize chances of this species causing economic impacts on crop production in Hawaii. We discuss the possibility of improving biological control of B. latifrons through augmentative releases of F. arisanus or introduction and release of specific and efficient new parasitoid species.     

Alkylbenzoquinones with antiproliferative effect against human cancer cell lines from stem of Ardisia kivuensis

Two new alkylbenzoquinone derivatives, named as ardisiaquinone J (1) and K (2) were isolated from the MeOH extract of the stem of Ardisia kivuensis Taton (Myrsinaceae), together with the known lupeol and β-sitosterol. Their structures were elucidated on the basis of spectroscopic analysis and comparison with authentic samples. The new compounds exhibited considerable antiproliferative activity against Ishikawa, HeLa, MCF7 and A431 cell lines with IC₅₀ values between 6.64 and 15.40 μM. In addition, compound 2 exerted a moderate free radical scavenging effect on DPPH-assay.     

Campylobacter,salmonella and chlamydia in free-living birds of Croatia

Campylobacteriosis, salmonellosis and avian chlamydiosis are zoonotic diseases in which birds have been suggested to play an important role as reservoirs. We have investigated the prevalence of Campylobacter and Salmonella spp. and Chlamydophila sp. in 107 free-living birds belonging to 25 species from 13 families from Croatia in order to examine the natural infections caused by these agents. Campylobacter jejuni-like organisms were isolated from 2 of 107 free-living bird species examined (1.9%). Salmonella was isolated from 8 fresh fecal specimens from free-living bird species (7.4%). These isolates were identified as S. typhimurium in 4 (3.7%), and S. enteriditis in 4 (3.7%) free-living birds. These samples originated from feral pigeons (Columba livia domesticus; n=14; 28.6%), rook (Corvus frugilegus; n=13; 15.4%), buzzard (Buteo buteo; n=12; 16.7%), black-headed gull (Larus ridibundus; n=8; 12.5%) and tawny owl (Strix aluco; n=8; 12.5%). The presence of Chlamydophila sp. was not detected in the free-living birds examined during this study. Epidemiological aspects and possible significance of the examined birds as a source of infections for domestic animals and humans are discussed.     

Eastern Cottontail (<Emphasis Type="Italic">Sylvilagus Floridanus)</Emphasis> as Carrier of Dermatophyte Fungi

Eastern cottontail (Sylvilagus floridanus, fam. Leporidae), introduced into Piedmont (Italy) in the 1960s, was studied as carrier of dermatophyte fungi. Of 216 hair samples collected from animals culled between September 1999 and July 2000 in the Province of Alessandria (Piedmont, Italy) during a pest control project, 57 (26.4%) yielded dermatophyte colonies. As two different species of dermatophytes grew from two samples, a total of 59 fungal isolates (26.5%) were obtained. Six dermatophyte species both geophilic (M. gypseum, M. cookei, Trichophyton ajelloi, T. terrestre) and zoophilic (M. canis, T. mentagrophytes) were identified. No sex-related differences were found but season-related differences were observed. The highest prevalence of dermatophyte-positive samples was recorded in May–September, due to the geophilic fungi whose prevalence decreased during colder and increased during warmer months ( p < 0.001). The presence of zoophilic dermatophytes, T. mentagrophytes, commonly associated with rodents, small mammals and lagomorphs and M. canis, usually correlated with domestic environment, did not change the whole year round. As Eastern cottontail has been showed to be a carrier of dermatophytes transmissible to man (M. canis, T. mentagrophytes and M. gypseum), it may represent a source of infection for gamekeepers, hunters and veterinarians.     

LC-MS导向分离山壳骨中主成分及其生物活性研究

为了解山壳骨(Pseuderanthemum latifolium)的化学成分和生物活性,运用LC-MS联用技术分离得到羽扇豆醇(1)和豆甾醇(2)。体外活性评价结果表明,化合物1和2均具有中等的抗MRSA活性,但不具有神经保护作用。这是首次对山壳骨进行化学成分和生物活性研究,为综合开发与利用山壳骨提供科学依据。     

Introduction and establishment of parasitoids for the biological control of the apple ermine moth, Yponomeuta malinellus (Lepidoptera: Yponomeutidae), in the Pacific Northwest

Four parasitoids were imported from five countries in Eurasia and released in northwestern Washington, US, to control the apple ermine moth (AEM), Yponomeuta malinellus Zeller, which colonized the Northwest around 1981. From 1988 to 1991, 95,474 individuals of Ageniaspis fuscicollis (Dalman) from France, China, Korea, and Russia were released in Washington. Parasitism of AEM increased 4- to 5-fold over that produced by preexisting natural enemies between 1989 and 1994 at 22 monitored sites. Subsequently, the wasp dispersed up to 20 km from release sites. A. fuscicollis also parasitized the cherry ermine moth, Yponomeuta padellus (L.), which was discovered in the Pacific Northwest in 1993. A total of 1813 individuals of Herpestomus brunnicornis (Gravenhorst) from France, Korea, and Japan were released in 1989–1991, and 26 wasps were recovered in 1994–1995. From 1989 to 1991, 2647 Diadegma armillata (Gravenhorst) individuals from France were released. D. armillata was recovered at one site in 1991 two months following release, but no other recoveries have been made. A total of 8274 Eurystheae scutellaris(Robineau-Desvoidy) individuals were released in 1989 to 1991. However, this tachinid has not been recovered. A consistent decline of AEM populations occurred in 1989–1995, including at sites where A. fuscicollis was not recovered, suggesting other factors also contributed to this pest’s decline. Now well established in western Washington, A. fuscicollis may help suppress future outbreaks of Y. malinellus and its congener, Y. padellus.     

Antiprotozoal alkaloids from Galanthus trojanus

Two new alkaloid N-oxides, 1-O-acetyldihydromethylpseudolycorine N-oxide, and 11-hydroxyvittatine N-oxide, ten known alkaloids; arolycoricidine, haemanthamine, O-methylnorbelladine, narcidine, dihydrolycorine, 8-O-demethylmaritidine, stylopine and protopine, nicotinic acid and tyramine were isolated from Galanthus trojanus A.P. Davis & N. Özhatay (Amaryllidaceae). The chemical structures of the isolates were elucidated by UV, IR, MS, CD, 1D and 2D NMR experiments. The in vitro antiprotozoal and cytotoxic potentials of the compounds were also evaluated.     

Rice Chlorina-1 and Chlorina-9 encode ChlD and ChlI subunits of Mg-chelatase, a key enzyme for chlorophyll synthesis and chloroplast development

Photosynthetic organisms exhibit a green color due to the accumulation of chlorophyll pigments in chloroplasts. Mg-protoporphyrin IX chelatase (Mg-chelatase) comprises three subunits (ChlH, ChlD and ChlI) and catalyzes the insertion of Mg²⁺ into protoporphyrin IX, the last common intermediate precursor in both chlorophyll and heme biosyntheses, to produce Mg-protoporphyrin IX (MgProto). Chlorophyll deficiency in higher plants results in chlorina (yellowish-green) phenotype. To date, 10 chlorina (chl) mutants have been isolated in rice, but the corresponding genes have not yet been identified. Rice Chl1 and Chl9 genes were mapped to chromosome 3 and isolated by map-based cloning. A missense mutation occurred in a highly conserved amino acid of ChlD in the chl1 mutant and ChlI in the chl9 mutant. Ultrastructural analyses have revealed that the grana are poorly stacked, resulting in the underdevelopment of chloroplasts. In the seedlings fed with aminolevulinate-dipyridyl in darkness, MgProto levels in the chl1 and chl9 mutants decreased up to 25% and 31% of that in wild-type, respectively, indicating that the Mg-chelatase activity is significantly reduced, causing the eventual decrease in chlorophyll synthesis. Furthermore, Northern blot analysis indicated that the nuclear genes encoding the three subunits of Mg-chelatase and LhcpII in chl1 mutant are expressed about 2-fold higher than those in WT, but are not altered in the chl9 mutant. This result indicates that the ChlD subunit participates in negative feedback regulation of plastid-to-nucleus in the expression of nuclear genes encoding chloroplast proteins, but not the ChlI subunit.Haitao Zhang and Jinjie Li contributed equally to this work     

The Bionomics ofCoptera Haywardi(Ogloblin) (Hymenoptera: Diapriidae) and Other Pupal Parasitoids of Tephritid Fruit Flies (Diptera)

The endoparasitoidCoptera haywardi(Ogloblin) (Diapriidae) was discovered in Mexico attacking the pupae of the Mexican fruit fly,Anastrepha ludens(Loew). Typically, parasitoids of Diptera Cychlorrhapha pupae develop as ectoparasitoids and are generalists that attack hosts in a number of families. Aspects of the bionomics ofC. haywardiwere compared to those of two chalcidoid ectoparasitoids,Dirhinus himalayanusWestwood andSpalangia geminaBoucek.C. haywardideveloped in three genera of Tephritidae, but not in species of other families. The two species of chalcidoids developed in all the calypterate and acalypterate hosts to which they were exposed. In an olfactometerC. haywardipreferredAnastrepha suspensa(Loew) pupae, while the chalcidoids preferred the pupae ofMusca domestica L.This preference inS. geminawas diminished in insects that had been reared onA. suspensa. C. haywardioviposited in theA. suspensapupae that had been previously parasitized by the braconidDiachasmimorpha longicaudata(Ashmead). However, it completed development only in unparasitized pupae. Mortality of the primary parasitoid due toD. himalayanuswas approximately two-thirds the mortality inflicted on the host fly.S. geminadid not discriminate between parasitized and unparasitized pupae ofA. suspensaand developed in both.C. haywardiappears to have a more restricted host range relative to chalcidoid pupal parasitoids and this may be due to its endoparasitic development.     

Alkaloid profile and antimicrobial activity of <Emphasis Type="Italic">Lupinus angustifolius</Emphasis> L. alkaloid extract

Purpose of the present study was to evaluate alkaloid profile of the aerial parts of Lupinus angustifolius growing in Turkey by capillary gas chromatography-mass spectrometry (GC-MS). Fifteen alkaloids were identified by capillary GC-MS. 13α-Hydroxylupanine (50.78%) and lupanine (23.55%) were determined as the main alkaloids in the aerial parts of L. angustifolius. Ammodendrine, isoangustifoline, tetrahydrorhombifoline, angustifoline, α-isolupanine, 5,6-dehydrolupanine, 11,12-dehydrolupanine, 13α-acetoxylupanine, 13α-isovaleroyloxylupanine, 13α-valeroyloxylupanine, 13α-tigloyloxylupanine, 13α-cis-cinnamoyloxylupanine and 13α-cis-cinnamoyloxy-17-oxolupanine were identified as the minor alkaloids of the plant. Furthermore, antibacterial and antifungal activities of L. angustifolius alkaloid extract were tested against standard strains of the following bacteria; Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis and Staphylococcus aureus as well as the fungi; Candida albicans and C. krusei. The alkaloid extract showed significant activity on B. subtilis, S. aureus and P. aeruginosa while it was weakly active on E. coli. On the other hand, the extract possessed moderate activity against C. albicans and C. krusei.