NEWS
Hydrophilic metabolites produced by Penicillium solitum from Antartica
Our most recent article reports the results of a long-term screening which was developed during several years of method optimization, producing pre-fractionated extracts, obtaining bioassay results, selecting strains for isolation work and finally obtaining results. The achievements have been published in the 2020 January issue of the Journal of Natural Products, titled “Water-Soluble Glutamic Acid Derivatives Produced in Culture by Penicillium solitum IS1-A from King George Island, Maritime Antarctica“. Six new tryptophan-glutamic acid derivatives have been isolated and identified from the aqueous extract of the fungus growth medium. Our approach in using a mixture of XAD-2, XAD-4 and XAD-7 proved effective in capturing the compounds from the aqueous medium. The resins fraction was subsequently fractionated by C18 reversed-phase chromatography in order to obtain cleaner fractions suitable for HPLC-UV-MS analysis and bioassay testing. The metabolites have been isolated using different stationary phases, such as Sephadex LH20, Sephadex G-15, phenyl-derivatized SiOH, C8 derivatized SiOH (HPLC), C18 derivatized SiOH (HPLC). The majority of the compounds showed some fluorescence that hampered the bioassays evaluation. Read the full article here.
The photo of the graphical abstract has been taken by Dr. Lara Durães Sette, Professor at the Biosciences Institute of Universidade Estadual Paulista Julio de Mesquita Filho, at Rio Claro campus, during an expedition to the Antarctic Continent. It doesn’t look a photo, isn’t it? But, yes, it is a photo. Additional amazing photographs have been taken by her.
Other water-soluble metabolites produced by Penicillium solitum and by additional microbial strains will be soon reported by our group. Stay tuned!
Presentations at the 2020 Gordon Research Conferences on Marine Natural Products
Tomorrow starts the 2020 edition of the Gordon Research Conferences on Marine Natural Products, “Discovery, Functional Development and Enabling Technologies of Marine Natural Products”. Organized by Kirk Gustafson (Chair) and Kerry McPhail (Vice-Chair), the meeting will have an exciting, bold and diverse presentations program. Topics include “Cryptic Microbial Metabolites”, “Marine Natural Products as Therapeutics and Molecular Probes”, “New Tools in the Structure Elucidation Tool Box”, “Secondary Metabolite Biosynthesis, Enzymology and Genomics”, “Enhanced Screening and Discovery Platforms for Natural Products”, “Development and Application of New Enabling Technologies”, “Mechanisms of Action and Molecular Targets”, “Functional and Ecological Roles of Natural Products” and “Future Directions in Marine Natural Products Discovery”.
Our group will be presenting four posters.
Dr. Camila M. Crnkovic, a former Post-Doctoral Researcher in the group and now assistant professor at the Universidade de São Paulo, will present a poster on the first results of her post-doctoral project, “Improving and diversifying the production and investigating the biosynthesis of phomactins by the cultured fungus Biatriospora sp. CBMAI 1333”.
Mirelle Takaki, a PhD student who will soon present her thesis, will present a poster titled “The use of molecular network and in-house platforms to investigate the metabolic differences between endophytic and phytopathogenic Colletotrichum fungi”. Her poster results from a collaboration of our group with Professor Roger Linington’s group at the Simon Fraser University, Vancouver, Canada. Mirelle completed a one year visiting studentship at Professor Linington’s group in 2019.
Laura P. Ióca, a PhD student who was a one year visiting student at Professor Alessandra Eustáquio’s group at the University of Illinois, Chicago, will present a poster entitled “A novel family of NRP-PK affect motility and biofilm formation in the marine bacterium Pseudovibrio brasiliensis”. Her poster results from a collaboration between Professors Alessandra Eustáquio, Laura Sánchez and Aleksej Krunic groups at UIC with our group in Brazil.
I will be presenting a poster by various students working in Brazil, including Vitor F. Freire (PhD student), Fernando B. Graça (undergraduate student), Dr. Ariane F. Bertonha, Darlon I. Bernardi (PhD student), Lucas R. Silva (undergraduate student), along with a large team of collaborators. The poster, titled “New Biologically Active Marine-Derived Peptides of Fungal and Animal Origin” will show a series of peptides and peptidic derivatives recently isolated in our group.
We are very much looking forward to attend and participate in the exciting forthcoming 2020 GRC-MNP!
Publications of 2019 – Clathriamide, a peptide from the sponge Clathria (Clathria) nicoleae
The article “Clathriamide, an hexapeptide isolated from the marine sponge Clathria (Clathria) nicoleae” results of part of Vitor F. Freire PhD project on the investigation of marine sponge metabolites. The sample of Clathria (Clathria) nicoleae was provided to us by the Rio de Janeiro research team at Jardim Botânico, Fernando C. Moraes, Wladimir C. Paradas, Leonardo T. Salgado, Renato C. Pereira, Rodrigo L. Moura and Gilberto M. Amado-Filho. This team participated directly in the expedition to the Amazon river mouth that resulted in the discovery of a very extense coral reef. The discovery of this coral reef was a major breakthrough, reported in the article “An extensive reef system at the Amazon River mouth“. During the expedition several species of marine sponges were collected. One of which was Clathria (Clathria) nicoleae, investigated by Vitor.
The beautiful sponge picture was provided by the late Professor Gilberto M. Amado-Filho, who very sadly passed away in a motorcycle accident in 2019.
Clathriamide was isolated and identified from the sponge aqueous extract, using a procedure developed in our laboratory. The absolute configuration of the amino acids was established by hydrolysis of the peptide followed by derivatization with the recently developed reagent 5-fluoro-2,4-dinitrophenyl-Nα-L-tryptophanamide and UPLC-MS analysis. The 5-fluoro-2,4-dinitrophenyl-Nα-L-tryptophanamide reagent was developed by Mariam N. Salib and Professor Tadeusz Molinski, at the University of California, San Diego. See their article, here.
Why the use of Professor Molinski’s reagent was absolutely necessary to establish the complete absolute stereochemistry of clathriamide?
Because the regular Marfey-derivatized isoleucine standards did not resolved by UPLC-MS analyses. The use of Molinski’s reagent and of a UPLC C8 reversed phase column were essential to resolve the two isoleucine standards we used to complete the absolute configuration assignment of clathriamide. The authors thank to Professor Molinski for the generous gift of his reagent.
Clathriamide article was submitted to the Brazilian Journal of Pharmacognosy, in recognition to the outstanding editorial work by Professor Cid Aimbiré M. dos Santos (Departamento de Farmácia, Universidade Federal do Paraná) to the Brazilian Journal of Pharmacognosy. As the editor-in-chief of the journal, Professor Cid devoted large efforts to increase its quality and visibility, which increased the IF of this journal to almost 2.0.
The article is open-access, and can be downloaded here.
Você precisa fazer login para comentar.