The character of endogenous growth regulators in the course of development in the fungus Lentinus tigrinus

The character of endogenous growth regulators in different stages of growth and development ofLentinus tigrinus was followed by means of bioassays. The methanolic extract of differently old mycelium and fruiting body was chromatographically separated and tested for auxins by means of Avena coleoptile segments, for gibberellins by using lettuce seedlings and for cytokinins by measuring the content of chlorophyl in leaf segments of barley. Auxins were found only in young vegetative mycelium and in the growing young stalk. The level of gibberellins is more significant and it reaches the highest values in the vegetative mycelium, in the growing young stalk and in the differentiated cap. The content of auxin and gibberellin substances did not increase even in the medium after cultivation of mycelium. Bioassays of cytokinins show a slight stimulation in the vegetative mycelium and in the primordia of caps. Significant inhibition was ascertained in the fully developed stalk. The high quantities of cytokinins were found in caps when basidiospores were formed. The results show a close connection of endogenous growth substances with the growth and the development of the fungus and indicate their participation in differentiation processes.     

Variability of enzymatic activities in ligninolytic fungi Pleurotus ostreatus and Lentinus tigrinus after protoplasting and UV-mutagenization

Summary Protoplast preparation and UV-irradiation of mycelial fragments were used to study the variability of production of laccase, peroxidase and manganese-dependent peroxidase (MnP) involved in lignin degradation in Pleurotus ostreatus and Lentinus tigrinus. After protoplasting, the variability of production of all enzymes increased substantially and was comparable to that of isolates after mutagenesis.     

The ectomycorrhizal symbiosis: genetics and development

Ectomycorrhiza represents a symbiotic structure made between tree roots and filamentous hyphae. This new organ results from a favourable interaction between plant and microbes, taking place in the soil at the vicinity of the root. Diversity is extremely important in the rhizosphere, with large numbers of bacterial, fungal, nematode and invertebrate species. Therefore, partners of the mycorrhiza have to recognize each other and they do it by using diffusible rhizospheric molecules. This recognition leads to cellular interactions between root and fungal cells, driven by changes in gene and protein expression. The aim of this review is to describe the cellular, genetic and molecular events leading to the formation of the ectomycorrhizal tissues with an emphasis on gene expression and cell-to-cell communication.     

The effect of copper ions on the production of laccase by the fungus Lentinus (Panus) tigrinus

The basidiomycete Lentinus tigrinus was cultured in media containing copper ions added at different growth stages. Copper ions at increased concentrations decelerated of the fungal biomass accumulation. The later Cu²⁺ ions were added, the better the fungal mycelium developed, and the toxic effect of Cu²⁺ was less pronounced. The maximum laccase activity (47 U/ml) was observed in the presence of 1.5–2.0 mM Cu²⁺ added on day 4 of cultivation.     

The genetics of plant morphological evolution.

Considerable progress has been made in identifying genes that are involved in the evolution of plant morphologies. Elements of the ABC model of flower development are conserved throughout angiosperms, and homologous MADS-box genes function in gymnosperm reproduction. Candidate gene and mapping analyses of floral symmetry, sex determination, inflorescence architecture, and compound leaves provide intriguing glimpses into the evolution of morphological adaptations.     

Influence of lignin and oxygen on the growth and the lipid formation of the fungus Lentinus tigrinus

During cultivation of the filamentous fungus Lentinus tigrinus on a medium containing lignin, a high oxygen content stimulated the growth of the fungus and contributed to the yield of lipids. A high content of phosphatidic acid and a reduction in the level of phosphatidylethanolamine and phosphatidylserine were first detected in the composition of phospholipids. Changes in the composition of neutral lipids, such as variation in the ratio of esterified and free sterols, have occurred; thus, the amount of sterol esters reduced simultaneously with a decrease in the content of free fatty acids. Based on the obtained results, the possible role of phosphatidic acid as a second messenger in the process of the consumption of lignin by the fungus Lentinus tigrinus is discussed.     

The Fungal Genetics Stock Center: a repository for 50 years of fungal genetics research

The Fungal Genetics Stock Center (FGSC) was established in 1960 to ensure that important strains used in early genetics research were available to subsequent generations of fungal geneticists. Originally, only mutant strains were held. At present, any organism that has had its genome sequenced is a genetic system and so the FGSC has added many new organisms. The FGSC is well integrated in its core community and, as research came to depend on cloned genes, vectors and gene libraries, the FGSC included these materials. When the community expanded to include plant and human pathogens, the FGSC adopted these systems as well. Wild isolates from around the world have also proven instrumental in answering important questions. The FGSC holds tremendous diversity of the Neurospora species, which form the core of the collection. The growth in the number of strains distributed illustrates the growth in research on fungi. Because of its position near the centre of the fungal genetics effort, the FGSC is also the first to see trends in research directions. One recent example is the 300% jump in requests for strains of Neurospora crassa carrying a mutation that makes them sensitive to high salt concentration. These strains were seldom requested over many years, but became among our most popular resources following the demonstration of their utility in studying fungicide resistance. This exemplifies why materials need to be preserved without regard to their immediate perceived value and reinforces the need for long-term support for preservation of a broad variety of genetic resources.     

Diverted development of reproductive organs: A source of morphological innovation in land plants

Recent discussions of animal development, particularly at the level of molecular genetics, have emphasized modularity, dissociation and co-option as basic principles of evolutionary developmental biology. These concepts are discussed in relation to two specific structural innovations in land plant evolution: the leaves (microphylls) of lycopsids, and the interseminal scales ofBennettitales. Both structures appear to have been derived evolutionarily by the diverted development of reproductive organs. In the case of lycopsids, recent analyses of phylogenetic relationships suggest that leaves are sterilized sporangia modified for photosynthetic assimilation. In the case ofBennettitales, structural data suggest that the interseminal scales are sterilized cupules modified for protection of the ovules. In both cases, multiplication of reproductive organs seems to have accentuated functional redundancy, and together with the developmental autonomy (dissociation) already inherent in the modular construction of plants, appears to have facilitated sterilization and co-option of some of these structures for new purposes. Numerous other examples in plants illustrate the same principles.Dedicated to emer. Univ.-Prof. DrFriedrich Ehrendorfer on the occasion of his 70th birthday     

Limb,tooth, beak: Three modes of development and evolutionary innovation of form

The standard model of evolutionary change of form, deriving from Darwin’s theory via the Modern Synthesis, assumes a gradualistic reshaping of anatomical structures, with major changes only occurring by many cycles of natural selection for marginal adaptive advantage. This model, with its assertion that a single mechanism underlies both micro- and macroevolutionary change, contains an implicit notion of development which is only applicable in some cases. Here we compare the embryological processes that shape the vertebrate limb bud, the mammalian tooth and the avian beak. The implied notion of development in the standard evolutionary picture is met only in the case of the vertebrate limb, a single-primordium organ with morphostatic shaping, in which cells rearrange in response to signalling centres which are essentially unchanged by cell movement. In the case of the tooth, a single-primordium organ with morphodynamic shaping in which the strengths and relationships between signalling centres is influenced by the cell and tissue movements they induce, and the beak, in which the final form is influenced by the collision and rearrangement of multiple tissue primordia, abrupt appearance of qualitatively different forms (i.e. morphological novelties) can occur with small changes in system parameters induced by a genetic change, or by an environmental factor whose effects can be subsequently canalized genetically. Bringing developmental mechanisms and, specifically, the material properties of tissues as excitable media into the evolutionary picture, demonstrates that gradualistic change for incremental adaptive advantage is only one of the possible modes of morphological evolution.     

The role of laccase and peroxidase of Lentinus (Panus) tigrinus fungus in biodegradation of high phenol concentrations in liquid medium

The possibility of the usage of Lentinus tigrinus fungus strain VKM F-3616D for biodegradation of high (up to 5%) phenol concentrations in liquid medium and the involvement of laccase and peroxidase in this process have been studied. L. tigrinus fungus was demonstrated to effectively digrade phenol with easy biomass separation from the liquid. Decrease in phenol concentration was accompanied by increased secretion level and laccase activity at the preliminary stages of biodegradation, while that of peroxidase was at the latest stages of biodegradation. These enzyme secretions in distinct ratios and consequences are necessary for effective phenol biodegradation. An effective approach for phenol concentration decrease in the waste water of smoking shops in meat-processing factories using L. tigrinus fungus was described.     

The genetics of animal development

The stages of establishment of phenogenetics in the USSR are regarded in this paper. The major directions and schools in this field are described. Also, main achievements and conceptions developed by our phenogeneticists are analysed in detail.     

The form and productivity of the Maltese morphological diminutive

This paper examines the productivity and form of the morphological diminutive in Maltese. Maltese has lexical items and grammatical properties stemming from both Semitic and Indo-European roots; previous research has shown that there are different levels of productivity for Semitic and Indo-European morphology, which varies even among speakers. In addition, both the Semitic and Indo-European morphological diminutive may take several different forms in Maltese. The goals of this research are to determine whether native speakers of Maltese can use a morphological diminutive (like wuggie) rather than a lexical diminutive (like little wug); if they can, whether a default form exists for the morphological diminutive, and if so, whether the default form is Indo-European or Semitic in nature. A novel word elicitation task was used to test how speakers use the diminutive, and the results may be explained using a variety of different theoretical frameworks allowing for a hierarchical selection of a diminutive allomorph.     

Increased secretion of lignolytic enzymes by the Lentinus tigrinus fungus after addition of butanol and toluene in submerged cultivation

We studied the effects of butanol and toluene on secretion of lignolytic enzymes by the Lentinus tigrinus fungus during submerged cultivation. Addition of butanol and toluene during the trophophase was followed by an increase in laccase and peroxidase activity of the culture and change in the composition of phospholipids and fatty acids. The ratio of phosphatidylcholine and phosphatidic acid decreased, while the amount of lysophosphatidylcholine, phosphatidylethanolamine, phosphoinositides, phosphatidylserine, and unsaturated fatty acids decreased. These changes resulted in an increase in the unsaturation index.     

The development of genetics and population studies

The contribution of genetics and population studies to physical anthropology as reflected in the pages of our Journal is traced since its establishment in 1918. Major trends include the use of more genetic polymorphisms, the search for natural selection and genetic drift, the unraveling of population structure in a wide variety of ecological niches, and the recognition of the role of culture in human biology. Nonhuman primates have also been explored from the viewpoint of population genetic. Emphasis has been increasingly on process rather than classification.