26 research outputs found
Neoaustin: a meroterpene produced by Penicillium sp.
The title meroterpene neoaustin {systematic name: (1′S,2′R,3S,7′R,9′S,11′S,12′R)-11′-hydroxy-2,2,2′,9′,12′-pentamethyl-6′,15′-dimethylene-2,6-dihydro-13′-oxaspiro[pyran-3,5′-tetracyclo[7.5.1.01,11.02,7]pentadecane]-6,10′,14′-trione}, C25H30O6, comprises five rings, three six-membered and two five-membered. The absolute configuration was established based on [αD] = +166.91° (c 1.21, CH2Cl2). In the crystal, the molecules are connected into a supramolecular helical chain via O—H⋯O hydrogen bonds reinforced by C—H⋯O contacts
Biological control of citrus postharvest phytopathogens
Citrus are vulnerable to the postharvest decay caused by Penicillium digitatum, Penicillium italicum, and Geotrichum citri-aurantii, which are responsible for the green mold, blue mold, and sour rot post-harvest disease, respectively. The widespread economic losses in citriculture caused by these phytopathogens are minimized with the use of synthetic fungicides such as imazalil, thiabendazole, pyrimethanil, and fludioxonil, which are mainly employed as control agents and may have harmful effects on human health and environment. To date, numerous non-chemical postharvest treatments have been investigated for the control of these pathogens. Several studies demonstrated that biological control using microbial antagonists and natural products can be effective in controlling postharvest diseases in citrus, as well as the most used commercial fungicides. Therefore, microbial agents represent a considerably safer and low toxicity alternative to synthetic fungicides. In the present review, these biological control strategies as alternative to the chemical fungicides are summarized here and new challenges regarding the development of shelf-stable formulated biocontrol products are also discussed118COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPsem informação2018/03670-0; 2016/20547-2; 2018/13027-8; 2017/24462-
The AGC kinase YpkA regulates sphingolipids biosynthesis and physically interacts with SakA MAP kinase in Aspergillus fumigatus
Sphingolipids (SL) are complex lipids and components of the plasma membrane which are involved in numerous cellular processes, as well as important for virulence of different fungal pathogens. In yeast, SL biosynthesis is regulated by the "AGC kinases" Ypk1 and Ypk2, which also seem to connect the SL biosynthesis with the cell wall integrity (CWI) and the High Osmolarity Glycerol (HOG) pathways. Here, we investigate the role of ypkA(YPK1) in SL biosynthesis and its relationship with the CWI and the HOG pathways in the opportunistic human pathogen Aspergillus fumigatus. We found that ypkA is important for fungal viability, since the 1 ypkA strain presented a drastically sick phenotype and complete absence of conidiation. We observed that under repressive condition, the conditional mutant niiA::ypkA exhibited vegetative growth defects, impaired germination and thermosensitivity. In addition, the ypkA loss of function caused a decrease in glycosphingolipid (GSL) levels, especially the metabolic intermediates belonging to the neutral GSL branch including dihydroceramide (DHC), ceramide (Cer), and glucosylceramide (GlcCer), but interestingly a small increase in ergosterol content. Genetic analyzes showed that ypkA genetically interacts with the MAP kinases of CWI and HOG pathways, mpkA and sakA, respectively, while only SakA physically interacts with YpkA. Our results suggest that YpkA is important for fungal survival through the regulation of GSL biosynthesis and cross talks with A. fumigatus MAP kinase pathways9CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP462383/2014-82009/53546-5; 2015/17541-0; 2017/19694-3This study was supported by Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP Grant Numbers: 2009/53546-5, 2015/17541-0, and 2017/19694-3) and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq Grant Number 462383/2014-8), Brazil to IM. This work was also supported by NIH grants (AI116420 and AI125770) and by the VA Merit Award grant (I01BX002624) to MDP. The funding body had no role in designing the study or in collecting, analyzing and interpreting the data, or in writing the manuscrip
The AGC Kinase YpkA Regulates Sphingolipids Biosynthesis and Physically Interacts With SakA MAP Kinase in Aspergillus fumigatus
Sphingolipids (SL) are complex lipids and components of the plasma membrane which are involved in numerous cellular processes, as well as important for virulence of different fungal pathogens. In yeast, SL biosynthesis is regulated by the “AGC kinases” Ypk1 and Ypk2, which also seem to connect the SL biosynthesis with the cell wall integrity (CWI) and the High Osmolarity Glycerol (HOG) pathways. Here, we investigate the role of ypkAY PK1 in SL biosynthesis and its relationship with the CWI and the HOG pathways in the opportunistic human pathogen Aspergillus fumigatus. We found that ypkA is important for fungal viability, since the ΔypkA strain presented a drastically sick phenotype and complete absence of conidiation. We observed that under repressive condition, the conditional mutant niiA::ypkA exhibited vegetative growth defects, impaired germination and thermosensitivity. In addition, the ypkA loss of function caused a decrease in glycosphingolipid (GSL) levels, especially the metabolic intermediates belonging to the neutral GSL branch including dihydroceramide (DHC), ceramide (Cer), and glucosylceramide (GlcCer), but interestingly a small increase in ergosterol content. Genetic analyzes showed that ypkA genetically interacts with the MAP kinases of CWI and HOG pathways, mpkA and sakA, respectively, while only SakA physically interacts with YpkA. Our results suggest that YpkA is important for fungal survival through the regulation of GSL biosynthesis and cross talks with A. fumigatus MAP kinase pathways
Transcriptional profiling of a fungal granuloma reveals a low metabolic activity of Paracoccidioides brasiliensis yeasts and an actively regulated host immune response
Granulomas are important immunological structures in the host defense against the fungus Paracoccidioides brasiliensis, the main etiologic agent of Paracoccidioidomycosis (PCM), a granulomatous systemic mycosis endemic in Latin America. We have performed transcriptional and proteomic studies of yeasts present in the pulmonary granulomas of PCM aiming to identify relevant genes and proteins that act under stressing conditions. C57BL/6 mice were infected with 1x106 yeasts and after 8- and 12-weeks of infection, granulomatous lesions were obtained for extraction of fungal and murine RNAs and fungal proteins. Dual transcriptional profiling was done comparing lung cells and P. brasiliensis yeasts from granulomas with uninfected lung cells and the original yeast suspension used in the infection, respectively. Mouse transcripts indicated a lung malfunction, with low expression of genes related to muscle contraction and organization. In addition, an increased expression of transcripts related to the activity of neutrophils, eosinophils, macrophages, lymphocytes as well as an elevated expression of IL-1β, TNF-α, IFN-γ, IL-17 transcripts were observed. The increased expression of transcripts for CTLA-4, PD-1 and arginase-1, provided evidence of immune regulatory mechanisms within the granulomatous lesions. Also, our results indicate iron as a key element for the granuloma to function, where a high number of transcripts related to fungal siderophores for iron uptake was observed, a mechanism of fungal virulence not previously described in granulomas. Furthermore, transcriptomics and proteomics analyzes indicated a low fungal activity within the granuloma, as demonstrated by the decreased expression of genes and proteins related to energy metabolism and cell cycle
MassIVE MSV000093322 - Investigation of pectin deficiency in modulating the bioflavonoid profile of orange processing waste
MassIVE MSV000092088 - DATABASE Metabolomics analysis Phaseolus vulgaris treated with a biostimulant obtained from Corynebacterium glutamicum
Penicillium digitatum infection mechanisms in citrus: What do we know so far?
Penicillium digitatum is the major source of postharvest decay in citrus fruits worldwide. This fungus shows a limited host range, being able to infect mainly mature fruit belonging to the Rutaceae family. This highly specific host interaction has attracted the interest of the scientific community. Researchers have investigated the chemical interactions and specialized virulence strategies that facilitate this fungus's fruit colonization, thereby leading to a successful citrus infection. There are several factors that mediate and affect the interaction between P. digitatum and its host citrus, including hydrogen peroxide modulation, secretion of organic acids and consequently pH control, and other strategies described here. The recently achieved sequencing of the complete P. digitatum genome opened up new possibilities for exploration of the virulence factors related to the host-pathogen interaction. Through such techniques as RNAseq, RT-PCR and targeted gene knockout mediated by Agrobacterium tumefaciens, important genes involved in the fungal infection process in citrus have been reported, helping to elucidate the molecular mechanisms, metabolites and genetic components that are involved in the pathogenicity of P. digitatum. Understanding the infection process and fungal strategies represents an important step in developing ways to protect citrus from P digitatum infection, possibly leading to more productive citriculture1238584593CAPES - Coordenação de Aperfeiçoamento de Pessoal e Nível SuperiorFAPESP – Fundação de Amparo à Pesquisa Do Estado De São PauloSem informação2017/24462-4; 2018/03670-