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11.
Franco TM Rostirolla DC Ducati RG Lorenzini DM Basso LA Santos DS 《Archives of biochemistry and biophysics》2012,517(1):1-11
Administration of the current tuberculosis (TB) vaccine to newborns is not a reliable route for preventing TB in adults. The conversion of XMP to GMP is catalyzed by guaA-encoded GMP synthetase (GMPS), and deletions in the Shiguella flexneri guaBA operon led to an attenuated auxotrophic strain. Here we present the cloning, expression, and purification of recombinant guaA-encoded GMPS from Mycobacterium tuberculosis (MtGMPS). Mass spectrometry data, oligomeric state determination, steady-state kinetics, isothermal titration calorimetry (ITC), and multiple sequence alignment are also presented. The homodimeric MtGMPS catalyzes the conversion of XMP, MgATP, and glutamine into GMP, ADP, PP(i), and glutamate. XMP, NH(4)(+), and Mg(2+) displayed positive homotropic cooperativity, whereas ATP and glutamine displayed hyperbolic saturation curves. The activity of ATP pyrophosphatase domain is independent of glutamine amidotransferase domain, whereas the latter cannot catalyze hydrolysis of glutamine to NH(3) and glutamate in the absence of substrates. ITC data suggest random order of binding of substrates, and PP(i) is the last product released. Sequence comparison analysis showed conservation of both Cys-His-Glu catalytic triad of N-terminal Class I amidotransferase and of amino acid residues of the P-loop of the N-type ATP pyrophosphatase family. 相似文献
12.
Ernetti Julia R. Boschetti Joana P. Delazeri Francieli De Bastiani Veluma I. M. Pontes Mariana R. Ribeiro Luisa P. Lingnau Rodrigo Toledo Luís Felipe Lucas Elaine M. 《Hydrobiologia》2020,847(16):3355-3364
Hydrobiologia - Pithecopus rusticus is an endemic amphibian restricted to the type locality, in southern Brazil, and possibly endangered to extinction, due to habitat degradation. However, an... 相似文献
13.
Rodrigo Scheihing Leyla Cardenas Roberto F. Nespolo Paola Krall Katherina Walz Shiro Kohshima Pedro Labarca 《Hydrobiologia》2010,637(1):45-52
In small metazoan invertebrates classical taxonomic analyses can be ambiguous due to the limited number of morphological characters
available. This difficulty can yield incorrect estimates of species richness or taxa distribution. The Boeckella genus has been described as the dominant taxon of zooplankton assemblages in the Andean biogeographical region. In this genus,
taxonomic classification and delimitation of boundaries between species has long been problematic and controversial. Among
South American centropagids Boeckella gracilipes has been regarded as one of the most broadly distributed species, its presence having been reported from Ecuador to Tierra
del Fuego. However, in the high Andean plateau some centropagid populations identified as Boeckella gracilipes have also been considered as B. gracilipes titicacae or even identified as a different species, namely Boeckella titicacae. In an attempt to resolve the taxonomic status of the Centropagidae family from the high Andean plateau, we combined traditional
and multivariate morphological analyses (integral approach) with the molecular phylogenetic approach. The results obtained
allow us to conclude that centropagids collected from the high Andean plateau actually represent a different species, B. titicacae, not B. gracilipes. The phylogenetic reconstruction of the South American Centropagidae family indicated that B. gracilipes represents a sister taxon to B. titicacae. The present study stresses the usefulness of integrating alfa-taxonomy with morphometric and molecular approaches in order
to resolve species boundaries, to determine geographical distributions and to investigate evolutionary processes. 相似文献
14.
Rodrigo Arreola José Luis Villalpando Jonathan Puente-Rivera Jorge Morales-Montor Enrique Rudiño-Piñera María Elizbeth Alvarez-Sánchez 《Molecular biotechnology》2018,60(8):563-575
Previously, metalloproteinase was isolated and identified from Trichomonas vaginalis, belonging to the aminopeptidase P-like metalloproteinase subfamily A/B, family M24 of clan MG, named TvMP50. The native and recombinant TvMP50 showed proteolytic activity, determined by gelatin zymogram, and a 50 kDa band, suggesting that TvMP50 is a monomeric active enzyme. This was an unexpected finding since other Xaa-Pro aminopeptidases/prolidases are active as a biological unit formed by dimers/tetramers. In this study, the evolutionary history of TvMP50 and the preliminary crystal structure of the recombinant enzyme determined at 3.4 Å resolution is reported. TvMP50 was shown to be a type of putative, eukaryotic, monomeric aminopeptidase P, and the crystallographic coordinates showed a monomer on a “pseudo-homodimer” array on the asymmetric unit that resembles the quaternary structure of the M24B dimeric family and suggests a homodimeric aminopeptidase P-like enzyme as a likely ancestor. Interestingly, TvMP50 had a modified N-terminal region compared with other Xaa-Pro aminopeptidases/prolidases with three-dimensional structures; however, the formation of the standard dimer is structurally unstable in aqueous solution, and a comparably reduced number of hydrogen bridges and lack of saline bridges were found between subunits A/B, which could explain why TvMP50 portrays monomeric functionality. Additionally, we found that the Parabasalia group contains two protein lineages with a “pita bread” fold; the ancestral monomeric group 1 was probably derived from an ancestral dimeric aminopeptidase P-type enzyme, and group 2 has a probable dimeric kind of ancestral eukaryotic prolidase lineage. The implications of such hypotheses are also presented. 相似文献
15.
In the present paper, the distal end of a humerus referable to a Dendrocygninae anseriform bird is reported. The specimen was collected at the Monte Hermoso Formation (early Pliocene) of the Farola Monte Hermoso locality (Buenos Aires Province, Argentina). This record constitutes one of the oldest for the group in South America and elsewhere. The overview of the anseriform record in South America indicates a similar pattern to that of other localities across the world. Paleogene localities are dominated by non-Anatinae taxa, whereas more recent faunas are dominated by anatines. Following this pattern, in South America the Anatinae appears in the fossil record as recently as in the Pleistocene, probably arriving from North America during the Great American Biotic Interchange. Pleistocene and Recent anseriform avifaunas are dominated by Anatinae taxa, and this dominance is probably due to some “key characters” regarding reproductive biology. In fact, the anatines exhibit a high reproductive success probably due to the capability of having two molts per year, and that the parental care of the downy young is only conducted by the female. The combination of characters may have allowed anatines to dominate most aquatic environments, surpassing in diversity more plesiomorphic taxa. 相似文献
16.
Luiz Rodrigo Saldanha Gazzaneo Reinaldo Farias Paiva de Lucena Paulino Ulysses de Albuquerque 《Journal of ethnobiology and ethnomedicine》2005,1(1):1-8
This paper investigates the wealth of medicinal plants used by the Apatani tribe of Arunachal Pradesh. Apatani have traditionally settled in seven villages in the Ziro valley of Lower Subansiri district of Arunachal Pradesh in the Eastern Himalayan region of India. The present study has resulted in the documentation of 158 medicinal plant species used by the Apatani group of villages. These medicinal plant species were distributed across 73 families and 124 genera. Asteraceae was the most dominant family (19 species, 11 genera) of medicinal plants, followed by Zingiberaceae, Solanaceae, Lamiaceae and Araceae. For curing ailments, the use of aboveground plant parts was higher (80%) than the belowground plant parts in the Apatani group of villages. Of the aboveground plant parts, leaf was used in the majority of cases (56 species), followed by fruit. Different belowground plant forms such as root, tuber, rhizome, bulb and pseudo-bulb were used by Apatani as a medicine. About 52 types of ailments were cured by using these 158 medicinal plant species. The results of this study are further discussed in the changing socio-economic contexts. 相似文献
17.
18.
Eduardo Martínez-León Gastón Amable Rodrigo Jácamo María Elisa Picco Laura Anaya Enrique Rozengurt Osvaldo Rey 《Journal of cellular physiology》2019,234(11):20510-20519
Protein kinase D1 (PKD1) plays a vital role in signal transduction, cell proliferation, membrane trafficking, and cancer; however, the majority of the studies up to date had centered primarily on PKD1 functions in interphase, very little is known about its role during cell division. We previously demonstrated that during mitosis PKD1 is activated and associated with centrosomes, spindles, and midbodies. However, these observations did not address whether PKD1 was associated with mitosis regulation. Accordingly, we used rapidly acting PKD-specific inhibitors to examine the contribution of PKD1 the sequence of events in mitosis. We found that although PKD1 overexpression did not affect mitosis progression, suppression of its catalytic activity by two structurally unrelated inhibitors (kb NB 142-70 and CRT 0066101) induced a significant delay in metaphase to anaphase transition time. PKD1 inhibition during mitosis also produced the appearance of abnormal spindles, defects in chromosome alignment, and segregation as well as apoptosis. Thus, these observations indicate that PKD1 activity is associated with mitosis regulation. 相似文献
19.
Alves Leticia Rodrigues Rossatto Davi Rodrigo Rossi Mônica Lanzoni Martinelli Adriana Pinheiro Gratão Priscila Lupino 《Protoplasma》2020,257(2):597-605
Protoplasma - The application of Se to plants growing under Cd contamination may become an alternative strategy to minimize Cd damage. However, there is no specific information available regarding... 相似文献
20.
Rodrigo J. Mercader Nathan W. Siegert Andrew M. Liebhold Deborah G. McCullough 《Population Ecology》2011,53(2):271-285
Management programs for invasive species are often developed at a regional or national level, but physical intervention generally
takes place over relatively small areas occupied by newly founded, isolated populations. The ability to predict how local
habitat variation affects the expansion of such newly founded populations is essential for efficiently targeting resources
to slow the spread of an invasive species. We assembled a coupled map lattice model that simulates the local spread of newly
founded colonies of the emerald ash borer (Agrilus planipennis Fairmaire), a devastating forest insect pest of ash (Fraxinus spp.) trees. Using this model, we investigated the spread of A. planipennis in environments with different Fraxinus spp. distributions, and explored the consequences of ovipositional foraging behavior on the local spread of A. planipennis. Simulations indicate that increased larval density, resulting from lower host tree density or higher initial population
sizes, can increase the spread rate during the first few years after colonization by increasing a density-dependent developmental
rate and via host resource depletion. Both the radial spread rate and population size were greatly influenced by ovipositional
foraging behavior. Two known behaviors of ovipositing A. planipennis females, attraction towards areas with high ash tree density and attraction to stressed trees, had opposing effects on spread.
Results from this model illustrate the significant influence of resource distribution and foraging behavior on localized spread,
and the importance of these factors when formulating strategies to monitor and manage invasive pests. 相似文献