A New Species of Psychrophilic Basidiomycetous Yeasts Leucosporidium fasciculatum sp. nov.

A psychrophilic yeast with a basidiomycetous developmental cycle and properties corresponding to the genusLeucosporidium Fell et al. was isolated from the fruiting body of the edible spring mushroom Gyromitra esculenta Pers. picked near Moscow. However, the isolate differed from all Leucosporidium species described to date in a number of characteristics. The results of the study of the developmental cycle and of the cultural, morphological, physiological, and biochemical properties of the new isolate, strain KBP Y-3696, allow it to be assigned to a new species of the genus Leucosporidium.     

Cryptococcus nanyangensis sp. nov., A New Basidiomycetous Yeast Isolated from the Gut of Wood-Boring Larvae

Two strains of a novel basidiomycetous yeast species were isolated from the gut of wood-boring larvae collected in the Baotianman Nature Reserve, the central China. Sequence analysis of the D1/D2 domains of the large subunit (LSU) rRNA gene and internal transcribed spacer (ITS) regions showed that these yeasts belong to the Bulleromyces clade and formed a cluster together with eleven undescribed Cryptococcus species. The novel species differed from its closest known species, Cryptococcus rajasthanensis, by 3.3 % divergence (15 substitutions and 6 gaps over 630 bases) in the D1/D2 domains, and by 13.4 % divergence (41 substitutions and 27 gaps over 508 bases) in the ITS regions. Physiologically, the fermentation of glucose, galactose, sucrose, trehalose, and raffinose in Durham tubes was observed for the strains of this new yeast. Based on the phenotypical and molecular characteristics presented, the two strains are proposed as a new species, Cryptococcus nanyangensis sp. nov., with the type strain KCY-1^T (=CICC 1976^T = CBS 12474^T).     

Structural studies of the capsular polysaccharide of a non-neoformans Cryptococcus species identified as C. laurentii, which was reclassified as Cryptococcus flavescens, from a patient with AIDS

Cryptococcus flavescens, a strain originally identified as C. laurentii, was isolated from the cerebrospinal fluid of an AIDS patient, and the soluble capsular polysaccharide of the yeast was investigated. Glucuronoxylomannan (GXM) was obtained from C. flavescens under conditions similar to those used to obtain C. neoformans polysaccharide. However, the GXM differed from C. neoformans polysaccharide in the decreased O-acetyl group content. The structure of GXM was determined by methylation analysis, partial acid hydrolysis, NMR analyses, and controlled Smith degradation. These analyses indicated that GXM has the following structure: an alpha-(1-->3)-D-mannan backbone with side chains of beta-D-glucuronic acid residues bound to the C-2 position of the mannose residue. The C-6 position of the mannose is substituted with D-man-beta-(1-->4)-D-xyl-beta-(1--> disaccharide. Furthermore, the existence of side chains containing more than two xylose residues was suggested. This mannosylxylose side chain is a novel structure in polysaccharides of C. neoformans and other Cryptococcus species.     

Sexual biology of haploid and diploid males in the bumble beeBombus terrestris

Summary InB. terrestris diploid males develop normally into adults (Duchateau et al., 1994). The diploid males are similar in appearance to the haploid males, except that they are smaller. The size of the testis of diploid males, relative to the length of the radial cell, is smaller than that of haploid males. There is overlap in the frequency distribution with respect to body size and testis size. The spermatozoa of diploid males are larger than those of the haploids and the vasa deferentia contain fair less spermatozoa than those of haploid males of the same age. Countings and measurements of the spermatozoa, therefore, can give the best indication about the ploidy of the males. Diploid males are successful in mating. They mate at a younger age than haploid males and they die sooner. The number of vial offspring of diploid males, however, is very low. No queen that mated with a diploid male produced a colony, but a few queens did produce some progeny. These might have been triploid males and workers. InB. terrestris higher ploidy results in smaller individuals, whereas in several other species of the Hymenoptera it has been found to result in larger individuals.     

Molecular Epidemiology Reveals Genetic Diversity amongst Isolates of the Cryptococcus neoformans/C. gattii Species Complex in Thailand

To gain a more detailed picture of cryptococcosis in Thailand, a retrospective study of 498 C. neoformans and C. gattii isolates has been conducted. Among these, 386, 83 and 29 strains were from clinical, environmental and veterinary sources, respectively. A total of 485 C. neoformans and 13 C. gattii strains were studied. The majority of the strains (68.9%) were isolated from males (mean age of 37.97 years), 88.5% of C. neoformans and only 37.5% of C. gattii strains were from HIV patients. URA5-RFLP and/or M13 PCR-fingerprinting analysis revealed that the majority of the isolates were C. neoformans molecular type VNI regardless of their sources (94.8%; 94.6% of the clinical, 98.8% of the environmental and 86.2% of the veterinary isolates). In addition, the molecular types VNII (2.4%; 66.7% of the clinical and 33.3% of the veterinary isolates), VNIV (0.2%; 100% environmental isolate), VGI (0.2%; 100% clinical isolate) and VGII (2.4%; 100% clinical isolates) were found less frequently. Multilocus Sequence Type (MLST) analysis using the ISHAM consensus MLST scheme for the C. neoformans/C. gattii species complex identified a total of 20 sequence types (ST) in Thailand combining current and previous data. The Thai isolates are an integrated part of the global cryptococcal population genetic structure, with ST30 for C. gattii and ST82, ST83, ST137, ST141, ST172 and ST173 for C. neoformans being unique to Thailand. Most of the C. gattii isolates were ST7 = VGIIb, which is identical to the less virulent minor Vancouver island outbreak genotype, indicating Thailand as a stepping stone in the global spread of this outbreak strain. The current study revealed a greater genetic diversity and a wider range of major molecular types being present amongst Thai cryptococcal isolates than previously reported.     

Activity of the Yeasts Cryptococcus laurentii and Rhodotorula glutinis Against Post-harvest Rots on Different Fruits

More than 200 yeasts were selectively isolated from microbial populations on the surface of different fruits. Fifty of these isolates were tested against blue mould ( Penicillium expansum ) on wounded apples. Isolates LS-11 of Rhodotorula glutinis and LS-28 of Cryptococcus laurentii were the most effective antagonists. They were further evaluated at 20IC on different fruits (apples, pears, strawberries, kiwi fruits and table grapes) against several of the main post-harvest pathogens ( Botrytis cinerea, Penicillium expansum, Rhizopus stolonifer and Aspergillus niger ) and at 4IC on apples inoculated with P. expansum . At 20IC the antagonists significantly reduced rot incidence and showed a wide range of activity on different hostpathogen combinations; isolate LS-28 exhibited a higher and more stable activity than LS-11. Both yeasts were also effective against P. expansum in cold storage conditions. Populations of the two yeasts were assessed on wounded and unwounded surfaces of apples kept at both 20 and 4IC. At either temperature, isolate LS-28 reached greater densities in wounded tissues than LS-11, but had a lower ability to colonize unwounded apple skin. The two yeasts were able to grow in culture at temperatures ranging from 0 to 35IC. In assays performed in vitro at 24IC, the antagonists showed low sensitivity towards several fungicides commonly applied on fruits and vegetables.     

Cytotaxonomical studies in Tribulus terrestris and T. alatus (Zygophyllaceae)

The chromosome numbers and meiotic behaviour of twenty morphologically variable populations of 7. terrestris and four of T. alatus were studied and compared. All populations of /. terrestris were hexaploid (2n = 36). They fall in one of the three morphological–eytological groups: I) robust with normal meiosis and pollen grains, II) less–robust with abnormal meiosis and high frequency of smaller pollen grains, and III) mixture of type II and dwarf plants. Seed set was high in all but the dwarfs. It appears that group I reproduces sexually while the other two groups have a certain degree of apomixis, and that the dwarf plants probably resulted from the fusion of cytologically unbalanced gametes. Tribulus alatus populations were tetraploid (2n = 24). Bud material adequate for meiotic studies were unavailable, but the wide range in size of pollen grains indirectly signifies meiotic abnormalities. So far, only the tetraploid race has been examined, while other chromosome races may exist.     

An overview of the Bombus terrestris (L. 1758) subspecies (Hymenoptera: Apidae)

Bombus terrestris is one of the most abundant bumblebee species in the West-Palaearctic. Its widespread domestication results in the movement of many colonies. The aim of this paper is to describe the 9 subspecies currently recognised and to list some of their most obvious characteristics. Bombus terrestris is not declining anywhere, on the contrary, its synanthropic spread through domestication may be expected. However, its autumn and winter populations rely on a restricted choice of flowers so they may be threatened locally by scrub clearance and the destruction of their favourite autumnal flowers.     

New Insights into Plagiogrammaceae (Bacillariophyta) Based on Multigene Phylogenies and Morphological Characteristics with the Description of a New Genus and Three New Species

Plagiogrammaceae, a poorly described family of diatoms, are common inhabitants of the shallow marine littoral zone, occurring either in the sediments or as epiphytes. Previous molecular phylogenies of the Plagiogrammaceae were inferred but included only up to six genera: Plagiogramma, Dimeregramma, Neofragilaria, Talaroneis, Psammogramma and Psammoneis. In this paper, we describe a new plagiogrammoid genus, Orizaformis, obtained from Bohai Sea (China) and present molecular phylogenies of the family based on three and four genes (nuclear-encoded large and small subunit ribosomal RNAs and chloroplast-encoded rbcL and psbC). Also included in the new phylogenies is Glyphodesmis. The phylogenies suggest that the Plagiogrammaceae is composed of two major clades: one consisting of Talaroneis, Orizaformis and Psammoneis, and the second of Glyphodesmis, Psammogramma, Neofragilaria, Dimeregramma and Plagiogramma. In addition, we describe three new species within established genera: Psammoneis obaidii, which was collected from the Red Sea, Saudi Arabia; and Neofragilaria stilus and Talaroneis biacutifrons from the Mozambique Channel, Indian Ocean, and illustrate two new combination taxa: Neofragilaria anomala and Neofragilaria lineata. Our observations suggest that the biodiversity of the family is strongly needed to be researched, and the phylogenetic analyses provide a useful framework for future studies of Plagiogrammaceae.     

Osmotic shock tolerance and membrane fluidity of cold-adapted Cryptococcus flavescens OH 182.9, previously reported as C. nodaensis, a biocontrol agent of Fusarium head blight

Cryptococcus flavescens (previously reported as C. nodaensis), a biological control agent of Fusarium head blight, has been previously shown to have improved desiccation tolerance after cold adaptation. The goal of the current study was to determine the effect of cold adaptation on the physicochemical properties of C. flavescens that may be responsible for its improved desiccation tolerance. The results show that cold adaptation improves liquid hyperosmotic shock tolerance and alters the temperature dependence of osmotic shock tolerance. Fluorescence anisotropy was used to characterize differences in the membrane fluidity of C. flavescens with and without cold adaptation. Force curves from atomic force microscopy showed a significant increase in the cell wall spring constant after cold adaptation. Cold adaptation of C. flavescens during culturing was shown to produce smaller cells and produced a trend towards higher CFU yields. These results suggest that cold adaptation significantly alters the membrane properties of C. flavescens and may be an effective method of improving the desiccation tolerance of microorganisms. In addition, we provide information on the correct naming of the isolate as C. flavescens.     

Sexual Interactions Between Two Distantly Related Drosophila Species, D. melanogaster and D. willistoni (Diptera: Drosophilidae)

Molecular analysis suggests that the pomace fly Drosophila melanogaster acquired the P family of transposable elements from another Drosophila species, D. willistoni. Since the two species are distantly related, it has been assumed that transmission of P element DNA from D. willistoni to D. melanogaster was mediated by a vector. The possibility of an alternative mode of transmission was assessed by characterizing the sexual behaviors of D. willistoni males and females, then observing D. willistoni and D. melanogaster males and females to see whether males from one species interacted sexually with females from the other species in a laboratory setting. We observed that D. melanogaster males court D. willistoni females vigorously and, in some cases, stimulate the females to be receptive to copulation. However, D. willistoni males perform relatively little courtship in response to D. melanogaster females and do not attempt to copulate. Thus, it is unlikely that sexual interactions effected the transmission of P element DNA from D. willistoni to D. melanogaster in the flies' natural habitat.     

Sexual Attraction and Mating Patterns in Cylindrocorpus longistoma and C. curzii (Nematoda: Cylindrocorporidae)

Females of Cylindrocorpus longistoma and C. curzii excrete attractants which probably function to bring the sexes together before mating. Intraspecific and interspecific heterosexual and homosexual pairing experiments showed the attractants to be species specific as well as sex specific. Observations on mating behavior support the hypothesis that sexual attraction and copulation require independent stimuli.     

Multigene phylogeny of the southern bull-kelp genus Durvillaea (Phaeophyceae: Fucales)

Durvillaea (southern bull-kelp) is an economically and ecologically important brown algal genus that dominates many exposed, rocky coasts in the cold-temperate Southern Hemisphere. Of its five currently-recognized species, four are non-buoyant and restricted to the south-western Pacific, whereas one is both buoyant and widely distributed. Durvillaea has had an unsettled taxonomic history. Although its position within the brown algae (Phaeophyceae) has now been largely resolved through the use of molecular techniques, the taxonomic status of several Durvillaea species/morphotypes remains unresolved. Previous molecular phylogenetic studies of phaeophycean taxa have included few Durvillaea samples, and have consequently paid little or no attention to variation within this genus. The current study presents phylogenetic analyses of four genetic markers (mitchondrial: COI; chloroplast: rbcL; and nuclear: 18S and 28S) to resolve phylogenetic relationships within Durvillaea. Results support the monophyly of solid-bladed taxa D. willana, D. potatorum, and D. sp. A (an undescribed species from the Antipodes Islands), whereas the widespread, buoyant D. antarctica is paraphyletic, with solid-bladed D.chathamensis placed sister to a D. antarctica clade from northern NZ but within D. antarctica sensu lato. The phylogenetic and ecological diversity detected within D. antarctica indicate that it is a species complex of five deeply divergent clades. Under a phylogenetic species concept, Durvillaea can be interpreted as a complex of nine distinct evolutionary lineages, only one of which has an intercontinental distribution ('subantarctic'D. antarctica).     

Molecular phylogeny of basidiomycetous yeasts in the Cryptococcus luteolus lineage (Tremellales) based on nuclear rRNA and mitochondrial cytochrome b gene sequence analyses: proposal of Derxomyces gen. nov. and Hannaella gen. nov., and description of eight novel Derxomyces species

Phylogenetic relationships among the hymenomycetous yeasts in the Cryptococcus luteolus lineage of the Tremellales were examined based on sequence analyses of the 18S rRNA gene, 26S rRNA gene D1/D2 domain, internal transcribed spacer (ITS) region including 5.8S rRNA gene and mitochondrial cytochrome b gene. In addition to the Dioszegia clade, two clades represented by Bullera mrakii and Bullera sinensis, respectively, were revealed to be well-separated monophyletic groups in the lineage. These clades also exhibited distinguishable colony characters. Two new genera, Derxomyces gen. nov. (type species: Derxomyces mrakii comb. nov.) and Hannaella gen. nov. (type species: Hannaella sinensis comb. nov.), are proposed to accommodate the species in the B. mrakii and B. sinensis clades, respectively. Mainly based on D1/D2 and ITS sequence comparison, eight novel Derxomyces species were recognized from ballistoconidium-forming strains isolated from plant leaves. The new species and their type strains are as follows: Derxomyces boekhoutii (AS 2.3758(T)=CBS 10824(T)), Derxomyces hainanensis (AS 2.3467(T)=CBS 10820(T)), Derxomyces linzhiensis (AS 2.2668(T)=CBS 10827(T)), Derxomyces pseudocylindrica (AS 2.3778(T)=CBS 10826(T)), Derxomyces qinlingensis (AS 2.2446(T)=CBS 10818(T)), Derxomyces simaoensis (AS 2.3571(T)=CBS 10822(T)), Derxomyces wuzhishanensis (AS 2.3760(T)=CBS 10825(T)) and Derxomyces yunnanensis (AS 2.3562(T)=CBS 10821(T)).     

Degree of C(4) Photosynthesis in C(4) and C(3)-C(4)Flaveria Species and Their Hybrids : II. Inhibition of Apparent Photosynthesis by a Phosphoenolpyruvate Carboxylase Inhibitor

Hybrids have been made between species of Flaveria exhibiting varying levels of C₄ photosynthesis. The degree of C₄ photosynthesis expressed in four interspecific hybrids (Flaveria trinervia [C₄] × F. linearis [C₃-C₄], F. brownii [C₄-like] × F. linearis, and two three-species hybrids from F. trinervia × [F. brownii × F. linearis]) was estimated by inhibiting phosphoenolpyruvate carboxylase in vivo with 3,3-dichloro-2-dihydroxyphosphinoylmethyl-2-propenoate (DCDP). The inhibitor was fed to detached leaves at a concentration of 4 mm, and apparent photosynthesis was measured at atmospheric levels of CO₂ and at 20 and 210 mL L⁻¹ of O₂. Photosynthesis at 210 mL L⁻¹ of O₂ was inhibited 32% by DCDP in F. linearis, by 60% in F. brownii, and by 87% in F. trinervia. Inhibition in the hybrids ranged from 38 to 52%. The inhibition of photosynthesis by 210 mL L⁻¹ of O₂ was increased when DCDP was used, except in the C₄ species, F. trinervia, in which photosynthesis was insensitive to O₂. Except for F. trinervia, control plants with less O₂ sensitivity (more C₄-like) exhibited a progressively greater change in O₂ inhibition of photosynthesis when treated with DCDP. This increased O₂ inhibition probably resulted from decreased CO₂ concentrations in bundle sheath cells due to inhibition of phosphoenolpyruvate carboxylase. The inhibition of photosynthesis by DCDP is concluded to underestimate the degree of C₄ photosynthesis in the interspecific hybrids because increased direct assimilation of atmospheric CO₂ by ribulose bisphosphate carboxylase may compensate for inhibition of phosphoenolpyruvate carboxylase.     

Status of Life Cycle Assessment (LCA) activities in the Nordic Region

The status of Life Cycle Assessment (LCA) activities in the Nordic Region (period 1995-97) is presented, based on more than 350 reported studies from industrial companies and research institutes in Sweden, Denmark, Norway, and Finland. A large number of industrial sectors is represented, with car components, building materials, pulp and paper products, electronic components and packaging as the most important ones. All aspects of LCA methodology are used: 90% use impact assessment, 80% impact assessment and valuation step. In most studies, more than one valuation method is used for ranking environmental impacts. LCA studies are well integrated in the business activities in many large Nordic corporations. From the early attempts, more familiar with LCA methodology, LCA has been integrated in strategy development, product development, process development and, to some extent, marketing. LCA has not only been used in the strict sense presented in the ISO 14040-43 standards. The systems approach, which is the basis for LCA, has also been modified and used in Sustainable Product Development, and in Environmental Performance Indicator and Product Declarations development. Future applications should be within Environmental Impact Assessments.