Filogenia molecular do gênero Morganella Zeller (Fungi, Basidiomycota) utilizando marcadores ITS

With the development and improvement of techniques for molecular studies and their subsequent application to the systematic, significant changes occurred in the classification of gasteroid fungi. The genus Morganella belongs to the family Lycoperdaceae, and is characterized mainly by lignicolous habit and presence of paracapilicium. Recent data demonstrate the discovery of new species for the group and the existence of a wide variety of species occurring in tropical ecosystems. However, the phylogenetic relationships of the genus, as well as the taxonomic classification, still require revisions to be better understood, the literature studies that address this issue are still very scarce. Thus, the objective of this study was to conduct studies of molecular phylogeny with species of the genus Morganella, to enhance understanding of the phylogeny of the group by including tropical species data. For this, the specimens used both for DNA extractions as for morphological review were obtained from Brazilian and foreign herbaria. For morphological analysis were observed characters relevant to the group's taxonomy. For phylogenetic analysis the Maximum Parsimony and Bayesian Analyzes were used, using the internal transcribed spacer (ITS) of nuclear ribosomal DNA. In phylogenetic analyzes, representatives from Morganella form a monophyletic clade with good support value and based on these results the genus should not be included as subgenus of Lycoperdon. The analysis indicated that M. pyriformis was not grouped with other representatives of Morganella, and therefore should not be included in the group as representative of Apioperdon subgenus because it is a Lycoperdon representative. Moreover, M. fuliginea, M. nuda, M. albostipitata, M. velutina, M. subincarnata are grouped with high support values within the genus Morganella. Morganella arenicola based on morphological and molecular studies does not aggregate in Morganella. Morganella nuda was grouped with M. fuliginea giving indications that can be treated as an intraspecific variation. The results of the analyzes favor to a better understanding of the species of Morganella. However, additional studies using a greater number of species, as well as other molecular markers are needed for a better understanding of the phylogenetic of Morganella.

The importance of subclasses of chitin synthase enzymes with myosin-like domains for the fitness of fungi

TG and CF are funded by FEDER funds through the Operational Programme Competitiveness Factors e COMPETE and national funds by FCT e Foundation for Science and Technology under the strategic project UID/NEU/04539/2013. C.F. is a recipient of a postdoctoral fellowship from FCT-Fundac¸ ~ao para a Ci^encia e Tecnologia (SFRH/BPD/63733/2009). NG is funded by The Wellcome Trust (080088, 086827, 075470, 099215 & 097377), the FungiBrain Marie Curie Network and the Medical Research Council (UK).

Structural and Biochemical Dissection of the Trehalose Biosynthetic Complex in Pathogenic Fungi

Trehalose is a non-reducing disaccharide essential for pathogenic fungal survival and virulence. The biosynthesis of trehalose requires the trehalose-6-phosphate synthase, Tps1, and trehalose-6-phosphate phosphatase, Tps2. More importantly, the trehalose biosynthetic pathway is absent in mammals, conferring this pathway as an ideal target for antifungal drug design. However, lack of germane biochemical and structural information hinders antifungal drug design against these targets.

In this dissertation, macromolecular X-ray crystallography and biochemical assays were employed to understand the structures and functions of proteins involved in the trehalose biosynthetic pathway. I report here the first eukaryotic Tps1 structures from Candida albicans (C. albicans) and Aspergillus fumigatus (A. fumigatus) with substrates or substrate analogs. These structures reveal the key residues involved in substrate binding and catalysis. Subsequent enzymatic assays and cellular assays highlight the significance of these key Tps1 residues in enzyme function and fungal stress response. The Tps1 structure captured in its transition-state with a non-hydrolysable inhibitor demonstrates that Tps1 adopts an “internal return like” mechanism for catalysis. Furthermore, disruption of the trehalose biosynthetic complex formation through abolishing Tps1 dimerization reveals that complex formation has regulatory function in addition to trehalose production, providing additional targets for antifungal drug intervention.

I also present here the structure of the Tps2 N-terminal domain (Tps2NTD) from C. albicans, which may be involved in the proper formation of the trehalose biosynthetic complex. Deletion of the Tps2NTD results in a temperature sensitive phenotype. Further, I describe in this dissertation the structures of the Tps2 phosphatase domain (Tps2PD) from C. albicans, A. fumigatus and Cryptococcus neoformans (C. neoformans) in multiple conformational states. The structures of the C. albicans Tps2PD -BeF3-trehalose complex and C. neoformans Tps2PD(D24N)-T6P complex reveal extensive interactions between both glucose moieties of the trehalose involving all eight hydroxyl groups and multiple residues of both the cap and core domains of Tps2PD. These structures also reveal that steric hindrance is a key underlying factor for the exquisite substrate specificity of Tps2PD. In addition, the structures of Tps2PD in the open conformation provide direct visualization of the conformational changes of this domain that are effected by substrate binding and product release.

Last, I present the structure of the C. albicans trehalose synthase regulatory protein (Tps3) pseudo-phosphatase domain (Tps3PPD) structure. Tps3PPD adopts a haloacid dehydrogenase superfamily (HADSF) phosphatase fold with a core Rossmann-fold domain and a α/β fold cap domain. Despite lack of phosphatase activity, the cleft between the Tps3PPD core domain and cap domain presents a binding pocket for a yet uncharacterized ligand. Identification of this ligand could reveal the cellular function of Tps3 and any interconnection of the trehalose biosynthetic pathway with other cellular metabolic pathways.

Combined, these structures together with significant biochemical analyses advance our understanding of the proteins responsible for trehalose biosynthesis. These structures are ready to be exploited to rationally design or optimize inhibitors of the trehalose biosynthetic pathway enzymes. Hence, the work described in this thesis has laid the groundwork for the design of Tps1 and Tps2 specific inhibitors, which ultimately could lead to novel therapeutics to treat fungal infections.

Punctuated evolution and transitional hybrid network in an ancestral cell cycle of fungi

© Medina et al.Although cell cycle control is an ancient, conserved, and essential process, some core animal and fungal cell cycle regulators share no more sequence identity than non-homologous proteins. Here, we show that evolution along the fungal lineage was punctuated by the early acquisition and entrainment of the SBF transcription factor through horizontal gene transfer. Cell cycle evolution in the fungal ancestor then proceeded through a hybrid network containing both SBF and its ancestral animal counterpart E2F, which is still maintained in many basal fungi. We hypothesize that a virally-derived SBF may have initially hijacked cell cycle control by activating transcription via the cis-regulatory elements targeted by the ancestral cell cycle regulator E2F, much like extant viral oncogenes. Consistent with this hypothesis, we show that SBF can regulate promoters with E2F binding sites in budding yeast.

Internal carotid arterial canal size and scaling in Euarchonta: Re-assessing implications for arterial patency and phylogenetic relationships in early fossil primates.

Primate species typically differ from other mammals in having bony canals that enclose the branches of the internal carotid artery (ICA) as they pass through the middle ear. The presence and relative size of these canals varies among major primate clades. As a result, differences in the anatomy of the canals for the promontorial and stapedial branches of the ICA have been cited as evidence of either haplorhine or strepsirrhine affinities among otherwise enigmatic early fossil euprimates. Here we use micro X-ray computed tomography to compile the largest quantitative dataset on ICA canal sizes. The data suggest greater variation of the ICA canals within some groups than has been previously appreciated. For example, Lepilemur and Avahi differ from most other lemuriforms in having a larger promontorial canal than stapedial canal. Furthermore, various lemurids are intraspecifically variable in relative canal size, with the promontorial canal being larger than the stapedial canal in some individuals but not others. In species where the promontorial artery supplies the brain with blood, the size of the promontorial canal is significantly correlated with endocranial volume (ECV). Among species with alternate routes of encephalic blood supply, the promontorial canal is highly reduced relative to ECV, and correlated with both ECV and cranium size. Ancestral state reconstructions incorporating data from fossils suggest that the last common ancestor of living primates had promontorial and stapedial canals that were similar to each other in size and large relative to ECV. We conclude that the plesiomorphic condition for crown primates is to have a patent promontorial artery supplying the brain and a patent stapedial artery for various non-encephalic structures. This inferred ancestral condition is exhibited by treeshrews and most early fossil euprimates, while extant primates exhibit reduction in one canal or another. The only early fossils deviating from this plesiomorphic condition are Adapis parisiensis with a reduced promontorial canal, and Rooneyia and Mahgarita with reduced stapedial canals.

U-Pb geochronology of the Santa Cruz Formation (early Miocene) at the Río Bote and Río Santa Cruz (southernmost Patagonia, Argentina): Implications for the correlation of fossil vertebrate localities

© 2016 Elsevier Ltd.The early Miocene Santa Cruz Formation (SCF) in southern Patagonia hosts the Santacrucian South American Land Mammal Age (SALMA), whose age is known mainly from exposures along the Atlantic coast. Zircon U-Pb ages were obtained from intercalated tuffs from four inland sections of the SCF: 17.36 ± 0.63 Ma for the westernmost Río Bote locality, and 17.04 ± 0.55 Ma-16.32 ± 0.62 Ma for central Río Santa Cruz localities. All ages agree with the bounding age of underlying marine units and with equivalent strata in coastal exposures. New ages and available sedimentation rates imply time spans for each section of ~18.2 to 17.36 Ma for Río Bote and 17.45-15.63 Ma for central Río Santa Cruz (Burdigalian). These estimates support the view that deposition of the SCF began at western localities ~1 Ma earlier than at eastern localities, and that the central Río Santa Cruz localities expose the youngest SCF in southern Santa Cruz Province. Associated vertebrate faunas are consistent with our geochronologic synthesis, showing older (Notohippidian) taxa in western localities and younger (Santacrucian) taxa in central localities. The Notohippidian fauna (19.0-18.0 Ma) of the western localities is synchronous with Pinturan faunas (19.0-18.0 Ma), but older than Santacrucian faunas of the Río Santa Cruz (17.2-15.6 Ma) and coastal localities (18.0-16.2 Ma). The Santacrucian faunas of the central Río Santa Cruz localities temporally overlap Colloncuran (15.7 Ma), Friasian (16.5 Ma), and eastern Santacrucian faunas.

Nd and Sm isotopic record from fossil fish teeth recovered from ODP Site 177-1090

Neodymium (Nd) isotopes were measured on 181 samples of fossil fish teeth recovered from Oligocene to Miocene sections at Ocean Drilling Program Site 1090 (3700 m water depth) on Agulhas Ridge in the Atlantic sector of the Southern Ocean. A long-term decreasing trend toward less radiogenic Nd isotope compositions dominates the record. This trend is interrupted by shifts toward more radiogenic compositions near the early/late Oligocene boundary and the Oligocene/Miocene boundary. Overall, epsilon-Nd values at Agulhas Ridge are more radiogenic than at other Atlantic locations, and are similar to those at Indian Ocean locations. The pattern of variability is remarkably similar to Nd isotope results from Walvis Ridge (South Atlantic) and Ninetyeast Ridge (Indian Ocean). In contrast, Agulhas Ridge and Maud Rise Nd isotope records do not show similar patterns over this interval. Results from this study indicate that deep water in the Atlantic flowed predominantly from north to south during the Oligocene and Miocene, and that export of Northern Component Water (NCW) to the Southern Ocean increased in the late Oligocene. There is also evidence for efficient exchange of deep waters between the Atlantic sector of the Southern Ocean and the Indian Ocean, although the direction of deep water flow is not entirely clear from these data. The shifts to more radiogenic Nd isotopic compositions most likely represent increases in the flux of Pacific waters through Drake Passage, and the timing of these events reflect development of a mature Antarctic Circumpolar Current (ACC). The relative timing of increased NCW export and ACC maturation support hypotheses that link deep water formation in the North Atlantic to the opening of Drake Passage.

(Table 3, page 264), Composition of a manganese micronodule found in a fossil red clay bed from Western Timor

Chemical analyses are presented for two Cretaceous clays from Noil Tobee, Timor. Mineralogical examination has shown that they consist principally of quartz, feldspar, illite and chlorite, together with minor amounts of montmorillonite. Both chemically and mineralogically the clays are very similar to the recent argillaceous deep-sea sediments of the Pacific and Indian Oceans, which confirms Molengraaff's theory (1921) that they are of deep-sea origin. Further confirmation of this theory is provided by comparison of the composition of micromanganese nodules, separated from one of these clays, with that of manganese nodules from the Pacific Ocean.

Distribution of marine fungi in the North Sea

The ecology of the lower marine fungi, namely the thraustochytrides, in the Fladen Ground area (FLEX box) and other parts of the North Sea was studied during 5 cruises in 1975 and 1976. The number of fungi/liter and the number of species showed seasonal fluctuations in the surface water samples from all the stations. A high number was found in September 1976 and a lower number in March 1976. These numbers, however, revealed no seasonal fluctuations in the underlying sediments. In both the surface waters and the sediments, a consistingly low number of fungi was recorded for certain stations and a high number of fungi for others, the reason for this beeing unknown. The sediments revealed a very high number of fungi/liter. Observations on the distribution of various species are presented. Certain species occured more frequently at some stations than at others; certain species occured more in the water column, e.g. Ulkenia minuta, and still others in the sediments, e.g. Thraustochytrium multirudimentale.

(Table 1, page 1169) Chemical composition of land (fossil) manganese deposits rich in todorokite

Chemical, x-ray and other data are given for todorokite, (Mn, Mg, Ca, Ba, Na, K)2.Mn5O12.3H2O, from Charco Redondo, Cuba, Farragudo, Portugal, and Hüttenberg, Austria. Additional localities at Romanèche, France, Saipan Island, Bahia, Brazil and Sterling Hill, New Jersey, are noted. Delatorreite of Simon and Straczek (1958) is identical with todorokite.

Fossil associations from the middle and upper Eocene strata of the Pamplona Basin and surrounding areas (Navarre, western Pyrenees)

Fossil associations from the middle and upper Eocene (Bartonian and Priabonian) sedimentary succession of the Pamplona Basin are described. This succession was accumulated in the western part of the South Pyrenean peripheral foreland basin and extends from deep-marine turbiditic (Ezkaba Sandstone Formation) to deltaic (Pamplona Marl, Ardanatz Sandstone and Ilundain Marl formations) and marginal marine deposits (Gendulain Formation). The micropalaeontological content is high. It is dominated by foraminifera, and common ostracods and other microfossils are also present. The fossil ichnoasssemblages include at least 23 ichnogenera and 28 ichnospecies indicative of Nereites, Cruziana, Glossifungites and ?Scoyenia-Mermia ichnofacies. Body macrofossils of 78 taxa corresponding to macroforaminifera, sponges, corals, bryozoans, brachiopods, annelids, molluscs, arthropods, echinoderms and vertebrates have been identified. Both the number of ichnotaxa and of species (e. g. bryozoans, molluscs and condrichthyans) may be considerably higher. Body fossil assemblages are comparable to those from the Eocene of the Nord Pyrenean area (Basque Coast), and also to those from the Eocene of the west-central and eastern part of South Pyrenean area (Aragon and Catalonia). At the European scale, the molluscs assemblages seem endemic from the Pyrenean area, although several Tethyan (Italy and Alps) and Northern elements (Paris basin and Normandy) have been recorded. Palaeontological data of studied sedimentary units fit well with the shallowing process that throughout the middle and late Eocene occurs in the area, according to the sedimentological and stratigraphical data.

The relationship between vegetation and modern pollen assemblages on Mount Paggeo (NE Greece)

In this study, we investigated the relationship between vegetation and modern-pollen rain along the elevational gradient of Mount Paggeo. We apply multivariate data analysis to assess the relationship between vegetation and modern-pollen rain and quantify the representativeness of forest zones. This study represents the first statistical analysis of pollen-vegetation relationship along an elevational gradient in Greece. Hence, this paper improves confidence in interpretation of palynological records from north-eastern Greece and may refine past climate reconstructions for a more accurate comparison of data and modelling. Numerical classification and ordination were performed on pollen data to assess differences among plant communities that beech (Fagus sylvatica) dominates or co-dominates. The results show a strong relationship between altitude, arboreal cover, human impact and variations in pollen and nonpollen palynomorph taxa percentages.