Guillermo Fernandez-BunsterUniversidad de Valparaíso (Chile) | CINV · Escuela de Medicina
Associate Professor at University of Valparaíso
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PhD in Biological Sciences from the University of Bristol, UK, Thesis based on heterologous expression of PKS-NRPS gene cluster from a Thai fungal strain in A. oryzae. Msc. in Microbiology, Thesis based on the analysis of Quorum Sensing in two bacterial strains isolated from the Patagonia. Bioengineer, minor in Industry, Thesis based on the polyhydroxyalkanoates (PHAs - biodegradable polymer) in bacteria, using sugar beet molasses as carbon source.
July 2012 - July 2016
- PhD in Biological Sciences
- Research: Characterization, analysis and manipulation of torrubiellone A gene cluster from the filamentous fungi Torrubiella BCC2165 by heterologous expression in A. oryzae
March 2009 - March 2010
- Undergraduate Thesis
- Thesis: Production of polyhydroxyalkanoates, using sugar beet molasses as carbon source in two bacterial strains from the chilean Patagonia // Tesis: Produccion de polihidroxialcanoatos, utilizando melaza como fuente de carbono
Genus Deinococcus is characterized by an increased resistance toward reactive oxygen species (ROS). The chromosome of five strains belonging to this genus has been sequenced and the presence of a luxS-like gene was deduced from their genome sequences. The aim of this study was to assess if a complete QS circuit is present in Deinococcus sp. and if...
Biodegradable plastics are a promising material to produce several medical devices, such as stents, cardiac valves, and drug delivery systems, among others. This entry focuses on the use of polyhydroxyalkanoates as a biodegradable material. This polymer is produced by plants and bacteria, but the production and composition of the polymer depend upo...
The genus Penicillium, part of the Trichocomaceae family, has been one of the most common and more studied fungi, found in soil, organic rotting material, plants, outdoor environments, and food products, among others. Penicillium spp. are known for the production of mycotoxins, such as ochratoxin A and patulin, which affect the quality and physicoc...
Keywords: Bioplastics; Biopolymers; Polyhydroxyalkanoates; South America; Biodegradable Polymers This review aims to name and describe the research in South America on polyhydroxyalkanoates (PHAs), one of the most studied and analyzed biopolymers obtained from biological sources. In the last five years, many publications on this topic have surged f...
Infectious diseases are caused by a number of pathogenic microorganisms, such as bacteria, fungi, viruses, and parasites. These organisms can be spread from one person to another, as well as after exposure to an infected animal that contains pathogenic organisms for humans. According to WHO, in 2016, three of the top ten causes of death worldwide w...
Greetings to all!
I have the opportunity to work with different isolates of Salmonella, but my expertise is mainly the production of secondary metabolites in bacteria and fungi. Do you have any information about compounds of interest from Salmonella?
I have found some bacteriocins, but I would like to know if I am missing something
I wrote a review about PHA research in Latin America, ranging from 2005 to 2017. I haven't managed to find an adequate journal to send it. The only "possitive" answer I got was that I should write only about the three last years, but no 12 years.
I have used antiSMASH, but I was expecting a bigger number of gene clusters.
I cannot use InterProScan, because I have only DNA sequencing, and also my sequence is not part of any database. I have it in FASTA format.
To write a comprehensive review about the research related to polyhydroxyalkanoates in Latin America to enhance the communication between research groups in the continent.
Paper: Bacterial biosynthesis of polyhydroxyalkanoates in Sphingopyxis chilensis S37 and Cupriavidus sp. PZK, using sugar beet molasses as carbon source. Submitted, but not accepted. It is an old project from my BSc. Degree, but it would like to "revive" it.
Thesis' Abstract: Torrubiellones A-D, extracted from Torrubiella sp. BCC2165, are structurally similar to 2-pyridone compounds produced in related arthropod-pathogenic fungi, such as tenellin and desmethylbassianin in Beauveria bassiana and militarinone in Cordyceps militaris. Torrubiellone A is particularly interesting because it has antimalarial activity (IC50 value of 8.1 µM), with very weak accompanying cytotoxicity. It was predicted that combining knowledge of the gene clusters responsible for the biosynthesis of the structurally similar compounds with in-silico analysis of the Torrubiella genome sequence would lead to the identification of the torrubiellone A biosynthetic gene cluster. Torrubiella sp. BCC2165 DNA was extracted, sequenced and analysed using secondary metabolite gene cluster prediction software to reveal a putative torrubiellone A gene cluster, comprising torS encoding a hybrid polyketide synthase-nonribosomal peptide synthetase, torA and torB encoding two P450 cytochromes and torC encoding an enoyl reductase. Comparison to the tenellin and desmethylbassianin gene clusters identified two additional genes, torD and torE, which could be responsible for structural differences between torrubiellone A and desmethylbassianin. The torS (fused to eGFP) was assembled without introns by homologous recombination in yeast and combined with other biosynthetic genes either from the putative torrubiellone cluster (torA, torB and torC), or from the desmethylbassianin gene cluster (dmbA, dmbB and dmbC) on a multigene expression vector. Assembled plasmids were used to transform the filamentous fungus Aspergillus oryzae NSAR1, yielding strongly yellow-pigmented transformants. Analysis of organic extracts from transformants by liquid chromatography-mass spectroscopy indicated that the production of torrubiellone-related compounds hasd been achieved. At the same time, torD and torE gene functions were investigated by co-expressing these genes in a tenellin-producing A. oryzae transformant, resulting in the addition of a hydroxyl group to the tenellin compound. A novel torrubiellone-related compound was detected when all six tor genes cluster were co-expressed in A. oryzae. A Torrubiella transformation system was developed, initially for promoter analysis of the torD and torE genes because the start codon of torE lies only 17 bp downstream of the torD stop codon in the Torrubiella genome, yet the two genes are transcribed independently. The analysis confirmed that the torE promoter is encoded within and as part of the torD coding region. The potential regulatory function of two transcription factors, ZnTF and C6TF, whose genes flank the torrubiellone biosynthetic genes, was investigated by over-expression in the native host. Overexpression of ZnTF led to the production of novel compounds, but no role, either positive or negative, was found for C6TF. The potential for genetic analysis by gene knockout in Torrubiella was tested with the torS gene. Transformants generated by homologous recombination were detected, as well as ectopic events, but the system requires improvement particularly in the isolation of homokaryons post-transformation.