Westerdykella globosa,a proposal for a new combination

The surface ornamentation of ascospores ofPreussia globosa was compared in an isolate from paddy soil in Japan and a culture derived from the holotype. The ascospores of two cultures were characterized by the surface ornamentation of a single, semicircular spiral ridge. This new finding strongly suggested that the fungus should be transferred to the genusWesterdykella. Therefore, the morphological and cultural characters of the fungus were re-examined, and the new combinationWesterdykella globosa is herein proposed.     

Inbreeding in a french peasant population

Genealogical pedigrees were collected from 976 farming couples who lived in a canton of central France in the XIXth and XXth century. Several methods (genealogical, isonymic and probability of origin of genes) were used to appraise the evolution of the biological structure of this population, which has gone through two phases. The first phase from 1800 to the World War I, shows gene flows between the farming population of the canton and those of neighbouring rural districts which are linked to an increase in consanguineous marriages. The second phase, from 1920 onwards, shows important gene flow from distant areas. This trend implies a decrease in consanguineous marriages.     

<Emphasis Type="Italic">hedgehog</Emphasis> is a segment polarity gene in a crustacean and a chelicerate

The evolution of arthropod segmentation has been studied by comparing expression patterns of pair-rule and segment polarity genes in various species. In Drosophila, the formation and maintenance of the parasegmental boundaries depend on the interactions between the wingless (wg), engrailed (en) and hedgehog (hh) genes. Until now, the expression pattern of hh has not been analysed to such a great extent as en or wg. We report the cloning and expression analysis of hh genes from Euscorpius flavicaudis, a chelicerate, and Artemia franciscana, a branchiopod crustacean. Our data provide evidence that hh, being expressed in the posterior part of every segment, is a segment polarity gene in both organisms. Additional hh expression sites were observed in the rostrum and appendages of Euscorpius and in the gut of Artemia. From the available data on hh expression in various bilaterians, we review the various hypotheses on the evolution of hh function and we suggest an ancestral role of hh in proctodeum specification and gut formation.Edited by D. Tautz     

Cyanobacteria dynamics in a restored Finnish lake: a long term simulation study

Several explanations have been presented for the formation of lacustrine cyanobacteria blooms. These include elevated water temperature, nutrient enrichment, low N/P ratios, low light energy requirements, high pH and/or low carbon dioxide concentration, selective zooplankton grazing, excretion of compounds which suppress the growth of competing algae, and migration. The impact of the first four were studied in Lake Tuusulanjärvi, a eutrophic Finnish lake, using deterministic simulation. The study, which covered 15 years, included a sequence of cases on the recovery of the lake after the implementation of two restoration measures: aeration of the hypolimnion, and termination of municipal waste discharge, both of which were done during the study period. The focus was on Microcystis and Oscillatoria, and on the N-fixing cyanobacteria, Anabaena and Aphanizomenon. Eukaryotic phytoplankton were also included in the study. Monitoring data were used. The roles of the hypotheses were discussed, from the point of view of the utility of the information in water resources management.     

Stomatal conductance in a tropical xerophilous shrubland at a lava substratum

Diurnal variation in leaf stomatal conductance (g _s) of three xerophilous species (Buddleia cordata, Senecio praecox and Dodonaea viscosa) was measured over a 10-month period during the dry and wet seasons in a shrubland that is developing in a lava substratum in Mexico. Averaged stomatal conductances were 147 and 60.2 (B. cordata), 145 and 24.8 (D. viscosa) and 142.8 and 14.1 mmol m^–2 s^–1 (S. praecox) during the wet and dry season respectively. Leaf water potential () varied in a range of –0.6 to –1.2 (S. praecox), –0.6 to –1.8 (B. cordata) and –0.9 to –3.4 MPa (D. viscosa) during the same measurement periods. Stomata were more sensitive to changes in irradiance, air temperature and leaf–air vapour pressure difference in the rainy season than the dry season. Although stomatal responses to were difficult to distinguish in any season (dry or rainy), data for the entire period of measurement showed a positive correlation, stomata tending to open as increased, but there is strong evidence of isohydric behaviour in S. praecox and B. cordata. A multiplicative model relating g _s to environmental variables and to accounted for 79%–83% of the variation of g _s in three sites (pooled data); however, the performance of the model was poorer (60%–76%) for individual species from other sites not included in the pooled data.     

Site selection by a social wasp in a nesting association (Hymenoptera: Vespidae)

The tropical social waspMischocyttarus immarginatus is a nesting associate ofPolybia occidentalis in northwestern Costa Rica. We show that an activeP. occidentalis colony is a necessary component of aM. immarginatus nesting site in this part of the latter’s range.M. immarginatus foundresses actively seekP. occidentalis colonies to initiate nests at a modal distance of 8 cm from them. There is an 18-mm lower limit to how closeM. immarginatus can nest in relation toP. occidentalis. At distances of less than this,P. occidentalis workers can reach theM. immarginatus nest while standing on their own nest and robM. immarginatus of its brood when the adults are absent.     

Utilisation of a tropical bay as a nursery area by sharks of the families Carcharhinidae and Sphyrnidae

Synopsis At least eight species of sharks of the families Carcharhinidae and Sphyrnidae use Cleveland Bay in northern Australia as a communal nursery area.Carcharhinus dussumieri, C. fitzroyensis, C. limbatus andC. tilstoni use the bay as a seasonal primary nursery, with juveniles occurring in it for only a few months each year immediately after birth. Alternatively,Carcharhinus sorrah, Rhizoprionodon acutus andR. taylori use the bay as a year-round primary and secondary nursery, with juveniles remaining in it up to the size at maturity. AdultR. taylori also persist in the bay, a behavioural pattern possibly explained by their small maximum size. While present immediately after birth the type of utilisation pattern displayed bySphyrna lewini could not be clarified in this study. Although diets of these species in the bay are similar, there is probably little direct competition for food due to the highly productive habitats in the bay supporting an abundance of food resources. The highest numbers of juveniles occur when prey species are the most abundant, and when temporal separation of some seasonally-occurring species of sharks in effect.     

Aspergillus myositis in a patient with a myelodysplastic syndrome

We present the case of an elderly man who, while being treated with corticosteroids for a myelodysplastic syndrome, developed myositis of the calf due to Aspergillus fumigatus. Despite therapy with amphotericin B the myositis failed to resolve and he died. At autopsy, a localized necrotizing myositis of the right calf was found with no evidence of disseminated Aspergillus infection. Myositis in the setting of disseminated candidiasis or cryptococcosis has been previously reported. This case is unique in that it is the first reported case of localized fungal myositis and of myositis caused by Aspergillus.     

The Lipomycetaceae,a model family for phylogenetic studies

The Lipomycetaceae (Endomycetales) are known from the generaDipodascopsis, Lipomyces andZygozyma with budding anamorphic states inMyxozyma. The family is easily recognized culturally and physiologically but is phenotypically and ecologically extremely diverse. This natural taxon is phylogenetically distinct from the Saccharomycetaceae, but probably related to the Dipodascaceae. The possible evolution of the lipomycetaceous anamorphs is discussed.     

Geitlerinema,a new genus of oscillatorialean cyanophytes

Certain related oscillatorialean species, originally attributed to the genusOscillatoria and recently assigned to subg.Geitlerinema of the genusPhormidium (Phormidiaceae-Phormidioideae), are revised and reclassified. Based on a reevaluation of the diacritical features, subg.Geitlerinema is raised to generic rank and assigned to the familyPseudanabaenaceae (tentatively to subfam.Pseudanabaenoideae). The individual species are reviewed and the necessary new combinations are made.Dedicated to Prof. DrLothar Geitler on the occasion of his 90th birthday.     

Analysis of a plastid gene cluster reveals a close relationship betweenCyanidioschyzon andCyanidium

Cyanidioschyzon merolae andCyanidium caldarium are representative species among of the most primitive algae, although the two species are distinctly different in various morphological traits. We determined the nucleotide sequence of therbcL gene and a flanking 8-kb region in the plastid genome of each of these algae. In both algae, 12 genes were identified in this region, in an identical order. This gene order is not conserved in the plastid genomes of other species of the kingdom Plantae that have been sequenced to data. An additional unidentified open reading frame was also found in the two algae that we analyzed, which has not been described in any other species of algae includingPorphyra purpurea. Comparison of the amino acid sequences of selected genes also supported the conclusion thatCyanidioschyzon merolae andCyanidium caldarium are closely related and that they are distinct from other rhodophytes. The nucleotide sequence data reported in this paper will appear in the DDBJ, EMBL and GenBank Nucleotide Sequence Databases under the accession numbers D63675 and D63676.     

Changes in a hydropsychid guild downstream from a eutrophic impoundment

The production of unicellular algae is laborious and is a major constraint for the culturing of aquatic filter-feeders. Because of their small particle size and their high protein content yeasts are considered as a promising substitute for micro-algae. Furthermore, recent work has shown that baker's yeast can be converted into a digestible diet for Artemia by chemical treatment. The present study documents the use at laboratory scale of this manipulated yeast as an algal substitute for the culture of two anostracan species. The experiments were conducted with the brine shrimp artemia franciscana and the fairy shrimp Streptocephalus proboscideus. A similar experimental set-up was used for both species. The algal diet, consisting of Dunaliella tertiolecta for A. franciscana and Selenastrum capricornutum for S. proboscideus, was substituted at various levels by two types of treated baker's yeast: a fresh form and a dried product which was rich in highly unsaturated fatty acids (HUFA). The chemically-treated yeast offers promising possibilities as an algal substitute for Artemia; i.e. replacing 75% of the algae by the dried yeast resulted in similar survival and even higher growth rates in comparison with the reference algal diet; for the treated fresh yeast similar results could be achieved by up to 95% substitution. For S. proboscideus, a substitution of 75% by either of the yeast products resulted in good survival, though growth did not exceed 80% of the observed growth in the algal control. A diet consisting solely of yeast resulted in poor survival for larvae of both species. Experiments were run to investigate whether this was due to a sub-optimal feeding regime, nutritional deficiencies, or deterioration of the water quality.     

A role for glutamate decarboxylase during tomato ripening: the characterisation of a cDNA encoding a putative glutamate decarboxylase with a calmodulin-binding site

A tomato fruit cDNA library was differentially screened to identify mRNAs present at higher levels in fruit of the tomato ripening mutant rin (ripening inhibitor). Complete sequencing of a unique clone ERT D1 revealed an open reading frame with homology to several glutamate decarboxylases. The deduced polypeptide sequence has 80% overall amino acid sequence similarity to a Petunia hybrida glutamate decarboxylase (petGAD) which carries a calmodulin-binding site at its carboxyl terminus and ERT D1 appears to have a similar domain. ERT D1 mRNA levels peaked at the first visible sign of fruit colour change during normal tomato ripening and then declined, whereas in fruit of the ripening impaired mutant, rin, accumulation of this mRNA continued until at least 14 days after the onset of ripening. This mRNA was present at much lower levels in other tissues, such as leaves, roots and stem, and was not increased by wounding. Possible roles for GAD, and its product -aminobutyric acid (GABA) in fruit, are discussed.     

Mycena auricoma,a new species ofMycena sectionRadiatae from Japan,andMycena spinosissima,a new record in Japan

Two lignicolous species ofMycena (Agaricales, Basidiomycetes) are described and illustrated from eastern, Japan:Mycena auricoma sp. nov., forming ephemeral coprinoid basidiomata and belonging to sectionRadiatae, was found on a dead fallen twig ofQuercus serrata. It appears to close to a Malaysian species,“Trogia” crinipelliformis. Mycena spinosissima in sectionSacchariferae, new to Japan, was collected from dead bark ofAphananthe aspera, a dead fallen inflorescence ofCryptomeria japonica, and a dead fallen twig ofQuercus serrata.     

Habitat quality as a predictor of spatial variation in blue tit reproductive performance: a multi-plot analysis in a heterogeneous landscape

Vertebrate studies have rarely investigated the influence of spatial variation in habitat richness on both short-term (breeding) and long-term (offspring recruitment) reproductive performance using simultaneously multi-patch, multi-habitat type and multi-year approaches at landscape level. Here we present results of such an approach using the influence of two oak tree (Quercus ilex, Q. humilis) species on reproductive performance in Corsican blue tits (Parus caeruleus ogliastrae) as a model system. We found that blue tits breeding in rich broad-leaved deciduous patches consistently laid eggs earlier in the season, and produced larger clutches and more fledglings of higher quality, than those breeding in poor evergreen patches. Also, parents, especially males, were in better physical condition in the broad-leaved deciduous than in the evergreen patches. Surprisingly, estimates of long-term effects of reproduction, such as recruitment rates of locally born offspring, did not differ between the two habitat types. Our results suggest that short-term breeding performance and phenotypic quality of both chicks and parents do not necessarily provide reliable information about contributions to following generations at a scale larger than that of the local study plot. Differences in reproductive performance between the two oak habitat types could not be attributed to density-dependent effects, differences in levels of nest predation, or differences in age structure of the birds. We suggest that habitats that are optimal for breeding are not necessarily optimal for survival after the breeding season.     

Identification and characterization of a pigment-producing denitrifying bacterium

Herein, a denitrifying bacterium that produced greenish fluorescent pigment under aerobic conditions was accidentally isolated from municipal sewage sludge. Using 16S-rDNA sequence analysis, we identified the isolate as Pseudomonas aeruginosa R12, with 100% similarity. We achieved the highest pigment production rate (1.36 mg/L/h) in a 1-L bioreactor under aerobic conditions, using the optimal culture parameters determined in this study: 37°C, pH 8.0, 200 rpm, 5 wm aeration, and medium containing succinate and (NH₄)₂SO₄. The pigment was not a secondary metabolite and had no antibacterial activity on its co-isolates. Under anaerobic conditions, the isolate produced mainly N₂ and behaved as a strong denitrifier, displaying synergistic denitrification with co-isolated denitrifiers. To our knowledge, herein we have described the first instance in which P. aeruginosa R12 produces a fluorescent pigment under aerobic conditions. This newly-isolated strain therefore shows potential as a commercial resource for natural pigment.     

Galig, a novel cell death gene that encodes a mitochondrial protein promoting cytochrome c release

Galectin-3 internal gene (Galig) was recently identified as an internal gene transcribed from the second intron of the human galectin-3 gene that is implicated in cell growth, cell differentiation, and cancer development. In this study, we show that galig expression causes morphological alterations in human cells, such as cell shrinkage, cytoplasm vacuolization, nuclei condensation, and ultimately cell death. These alterations were associated with extramitochondrial release of cytochrome c, a known cell death effector. Furthermore, Bcl-xL co-transfection significantly reduced the release of cytochrome c induced by galig expression, suggesting a common pathway between the cytotoxic activity of galig and the anti-apoptotic activity of Bcl-xL. This antagonism was not observed upon co-transfection of Bcl-2 and galig. Galig encodes a mitochondrial-targeted protein named mitogaligin. Structure-activity relationship studies showed that the mitochondrial addressing of mitogaligin relies on an internal sequence that is required and sufficient for the release of cytochrome c and cell death upon cell transfection. Moreover, incubation of isolated mitochondria with peptides derived from mitogaligin induces cytochrome c release. Altogether, these results show that galig is a novel cell death gene encoding mitogaligin, a protein promoting cytochrome c release upon direct interaction with the mitochondria.     

Fusarium nisikadoi, a new species from Japan

A new species ofFusarium, F. nisikadoi, isolated fromPhyllostachys nigra var.henonis (bamboo) andTriticum aestivum (wheat) in Japan, is described, illustrated and discussed. This species is differentiated from other known species of the genus by the following characteristics: whitish colony color, long zigzag-like chains of 0–3(-5)-septate clavate conidia, intermixed with pyriform conidia, produced mostly from monophialides and rarely from polyphialides in the aerial mycelium, very long and slender sporodochial conidia, and no chlamydospores. The long chains of septate conidia are known only in this species of the genusFusarium. The conidiophores on the aerial mycelium sometimes proliferate sympodially. The species is tentatively placed in the form-sectionLiseola.     

rtpA, a gene encoding a bacterial two-component sensor kinase, determines pathogenic traits ofPseudomonas tolaasii, the causal agent of brown blotch disease of a cultivated mushroom,Pleurotus ostreatus

Pseudomonas tolaasii strain PT814 produces extracellular toxins, tolaasins, and a volatile toxin, tovsin, that are responsible for the induction of brown blotch and rotting, respectively, in a cultivated mushroom,Pleurotus ostreatus. Insertions of single transposon mini-Tn5Km 1 into the chromosome ofP. tolaasii strain PT814 generated mutants that are pleiotropically defective in tolaasin and protease production, and altered in colony morphology. The mutants, however, produce tovsin at the level of wild-type. Variants phenotypically similar to the pleiotropic mutants ofP. tolaasii strain PT814 spontaneously occurred inP. tolaasii strain S8501 at 22–30°C in vitro. The occurrence of variants was significantly reduced in the presence of extracts ofP ostreatus or at a temperature of 15–20°C. ThertpA gene (rtpA=regulator gene of tolaasin production and other pleiotropic traits) isolated from aP. tolaasii strain PT814 gene library restored the wild-type phenotype in both the mini-Tn5km 1 insertion and spontaneous mutants. mini-Tn5km 1 insertions were also located in the allele ofrtpA. Nucleotide sequencing of thertpA DNA revealed an open reading frame of 2,751 bp predicted to encode a protein consisting of 917 amino acid residues with a molecular mass of 100.6 kDa and displaying the conserved amino acid sequence of both sensor, and receiver domains of “bacterial two-component regulators”. The data suggest that the machinery responding to environmental stimuli is essential for the pathogenic interaction ofP. tolaasii with the mushroom.