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Yeasts have been widely used as a model to better understand cell cycle mechanisms and how nutritional and genetic factors can impact cell cycle progression. While nitrogen scarcity is well known to modulate cell cycle progression, the relevance of nitrogen excess for microorganisms has been overlooked. In our previous work, we observed an absence of proper entry into the quiescent state in Hanseniaspora vineae and identified a potential link between this behavior and nitrogen availability. Furthermore, the Hanseniaspora genus has gained attention due to a significant loss of genes associated with DNA repair and cell cycle. Thus, the aim of our study was to investigate the effects of varying nitrogen concentrations on H. vineae's cell cycle progression. Our findings demonstrated that nitrogen excess, regardless of the source, disrupts cell cycle progression and induces G2/M arrest in H. vineae after reaching the stationary phase. Additionally, we observed a viability decline in H. vineae cells in an ammonium‐dependent manner, accompanied by increased production of reactive oxygen species, mitochondrial hyperpolarization, intracellular acidification, and DNA fragmentation. Overall, our study highlights the events of the cell cycle arrest in H. vineae induced by nitrogen excess and attempts to elucidate the possible mechanism triggering this absence of proper entry into the quiescent state. Take‐away: High concentrations of nitrogen inhibit proper quiescent arrest in Hanseniaspora vineae.The decline in viability of yeast is ammonium‐dependent.Ammonium excess leads to an increase in reactive oxygen species and mitochondrial hyperpolarization.Ammonium excess triggers intracellular acidification and DNA damage. [ABSTRACT FROM AUTHOR]

The antifungal activity of 20 monoterpenes, currently found as main compounds in many essential oils, were evaluated against the model yeast Saccharomyces cerevisiae. Minimal inhibitory concentration (MIC), Minimal fungicidal concentration (MFC), and the time/dosage effect of selected monoterpenes were determined. The results showed that oxygenated monoterpenes exhibited higher fungistatic and fungicidal activity than hydrocarbons. Among oxygenated monoterpenes, the more effectives were citral, geraniol, citronellol, and citronellal, with MIC and MFC values between 0.64 and 3.68 mM, and 1.56 and 6.25 mM, respectively. Time response experiments showed that the selected monoterpenes rapidly reduce yeast cell viability in a time and dose‐dependent manner. Moreover, the reduction of viability was associated with loss of cell membrane integrity. These results may aid in the selection of essential oils for the control of undesirable yeasts or fungi, and serve as a basis for the study of chemical structure influence on the mode of action of monoterpenes. Novelty impact statement: Oxygenated monoterpenes have more fungicidal activity against S. cerevisiae.Citral, citronellol, citronellal, and geraniol were the most efficient monoterpenes.Monoterpenes' fungicidal activity is involved with cell membrane damages. [ABSTRACT FROM AUTHOR]

The aim of this study is to evaluate Muscat sparkling wines from the traditional Asti region (Italy) and the new geographical indication "IG Farroupilha" (Brazil). We analyzed 23 commercial Muscat sparkling wines from Asti and Farroupilha. Sample characterization of the aromatic profile by headspace‐solid phase microextraction and gas chromatography detector yielded a total of 32 targeted components in Muscat wines. The multivariate analysis of data differentiates the Muscat sparkling wines based on origin: Brazilian or Italian. The main quantitative differences between wines are residual sugar, sulfite content, isoamyl acetate, hexyl acetate, limonene, rose oxide, linalool, and citronellol. The sensory analysis confirmed that Brazilian wines were less sweet with freshener aroma, whereas the Italian wines were more intense in aroma, complex, and sweet. These peculiarities can be associated with terroir, including technological processes that may be tailored to fit different wine styles for particular markets. Practical applications: The chemical and sensorial characterizations of sparkling wines produced in regions with geographical indication are important to differentiate products made in different regions. [ABSTRACT FROM AUTHOR]

Ripe rot is one of the most important bunch diseases of grapes in the highlands of southern Brazil and a matter of concern for winegrowers. Sixty‐one strains isolated from berries of Vitis labrusca and V. vinifera varieties with symptoms were classified by phylogenetic analysis of the sequences of β‐tubulin, glyceraldehyde‐3‐phosphate dehydrogenase, D1/D2 domain of 28S rDNA, and rDNA internal transcribed spacer. They were also characterized by morphology, and their pathogenicity was evaluated. The combined molecular data allowed identification of six Colletotrichum species: C. fructicola, C. kahawae and C. viniferum (gloeosporioides complex), C. limitticola, C. nymphaeae (acutatum complex), and C. karstii (boninense complex). This is the first report of C. karstii and C. limitticola associated with the ripe rot of grapes. Morphological characteristics varied within and among species, confirming their separation at the complex level. Pathogenicity tests on V. vinifera berries showed that the most prevalent species, C. viniferum (37.8%) and C. fructicola (36.1%), were more virulent than the less prevalent species C. limitticola and C. karstii. Our findings indicate that there is a high diversity of Colletotrichum species associated with ripe rot disease of grapes in Brazil. There were no clear differences in the distribution of Colletotrichum species between V. labrusca and V. vinifera varieties. The determination of fungal species responsible for grape ripe rot in Brazilian vineyards may contribute to further epidemiological studies and the development of more efficient prophylactic methods for ripe rot management. [ABSTRACT FROM AUTHOR]

ABSTRACT The use of natural additives, with low toxicity and good compatibility, for PVC is becoming increasingly attractive. In this study, soybean oil additives were prepared by air oxidation reactions and blending with PVC. The oxidation reaction produced a significant increase in the number of hydroxyl groups in soybean oil; however, this kind of reaction results in the formation of a heterogeneous structure due to free radical reactions in the medium. The oxidized soybean oil improved the compatibility with PVC due to an increase in the number of polar groups, such as hydroxyls, and thus a reduction in the amount of atactic polymer was observed. Furthermore, an increase in the molecular weight of the oxidized oil, as well as large amounts of polar groups contributes to reducing the migration of oil in the PVC. Regarding the crystallinity of PVC, the use of pure and oxidized soybean oil causes small changes in the crystalline phase of the polymer. Oxidized soybean oil has great potential for usage as a secondary plasticizer for PVC. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42102. [ABSTRACT FROM AUTHOR]

Cervical cancer is the second most common type of cancer in women worldwide. Several human papillomavirus (HPV) genotypes, sexual behavior, and socioeconomic profile represent major risk factors for the development of this carcinoma. Cervical invasive cancer is preceded by cellular abnormalities that can be identified by cytological or histological exams. In order to determine the prevalence and genotypes of HPV in women with abnormal cytology or histopathology, cervical cell samples from 256 patients were evaluated for the presence of HPV/DNA by polymerase chain reaction (PCR), followed by virus genotyping by restriction fragment length polymorphism (RFLP). A total of 113 samples (51.2%) were HPV/DNA positive. Viral genotyping showed that the most prevalent genotypes were HPV 16 (34.7%) and 58 (13.8%), followed by HPV 33 (9.72%), 11 (8.33%), 18 (5.55%), 53 (5.55%), and 6 (4.2%). Four samples (5.55%) exhibited multiple infections due to the great similarity of socioeconomic characteristics and sexual behavior of HPV positive women, it was not possible to establish a risk profile for female HPV infection. J. Med. Virol. 81:1270-1275, 2009. © 2009 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

The Brazilian Atlantic Forest is one of the world's major biodiversity hotspots and is threatened by a severe habitat loss. Yet little is known about the processes that originated its remarkable richness of endemic species. Here we present results of a large-scale survey of the genetic variation at the mitochondrial cytochrome b gene of the pitviper, jararaca lancehead ( Bothrops jararaca), and two closely related insular species ( Bothrops insularis and Bothrops alcatraz), endemic of this region. Phylogenetic and network analyses revealed the existence of two well-supported clades, exhibiting a southern and a northern distribution. The divergence time of these two phylogroups was estimated at 3.8 million years ago, in the Pliocene, a period of intense climatic changes and frequent fragmentation of the tropical rainforest. Our data also suggest that the two groups underwent a large size expansion between 50 000 and 100 000 years ago. However, the southern group showed a more marked signal of population size fluctuation than the northern group, corroborating evidences that southern forests may have suffered a more pronounced reduction in area in the late Pleistocene. The insular species B. alcatraz and B. insularis presented very low diversity, each one sharing haplotypes with mainland individuals placed in different subclades. Despite their marked morphological and behavioural uniqueness, these two insular species seem to have originated very recently and most likely from distinct costal B. jararaca populations, possibly associated with late Pleistocene or Holocene sea level fluctuations. [ABSTRACT FROM AUTHOR]

Promoters are DNA sequences located upstream of the transcription start site of genes. In bacteria, the RNA polymerase enzyme requires additional subunits, called sigma factors (σ) to begin specific gene transcription in distinct environmental conditions. Currently, promoter prediction still poses many challenges due to the characteristics of these sequences. In this paper, the nucleotide content of Escherichia coli promoter sequences, related to five alternative σ factors, was analyzed by a machine learning technique in order to provide profiles according to the σ factor which recognizes them. For this, the clustering technique was applied since it is a viable method for finding hidden patterns on a data set. As a result, 20 groups of sequences were formed, and, aided by the Weblogo tool, it was possible to determine sequence profiles. These found patterns should be considered for implementing computational prediction tools. In addition, evidence was found of an overlap between the functions of the genes regulated by different σ factors, suggesting that DNA structural properties are also essential parameters for further studies. HighlightsCurrently, promoter prediction still poses many challenges due to the characteristics of promoter sequences.A clustering technique was applied on promoter sequences related to the alternative sigma factors of Escherichia coli. Creating 20 distinct profiles.The results exhibited evidence of an overlap in gene functions between the sigma factors. These found patterns should be considered for implementing computational prediction tools. [ABSTRACT FROM AUTHOR]