Publications by authors named "Stephanie Braun-Galleani"

Chemical amination of the enzyme was demonstrated to favor immobilization onto polydopamine (PDA)-coated magnetic nanoparticles (MNPs) for the first time, to the best of the author's knowledge. MNPs prepared via hydrothermal synthesis were coated with PDA for the immobilization of naringinase. X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, and Fourier-transform infrared spectroscopy showed that the MNPs were composed mainly of FeO with an average size of 38.

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The yeast Komagataella phaffii (formerly called Pichia pastoris) is used widely as a host for secretion of heterologous proteins, but only a few isolates of this species exist and all the commonly used expression systems are derived from a single genetic background, CBS7435 (NRRL Y-11430). We hypothesized that other genetic backgrounds could harbor variants that affect yields of secreted proteins. We crossed CBS7435 with 2 other K.

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(formerly known as ) has become an increasingly important microorganism for recombinant protein production. This yeast species has gained high interest in an industrial setting for the production of a wide range of proteins, including enzymes and biopharmaceuticals. During the last decades, relevant bioprocess progress has been achieved in order to increase recombinant protein productivity and to reduce production costs.

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The mating-type switching endonuclease HO plays a central role in the natural life cycle of , but its evolutionary origin is unknown. is a recent addition to yeast genomes, present in only a few genera close to . Here we show that is structurally and phylogenetically related to a family of unorthodox homing genetic elements found in and yeasts.

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Humans have used yeasts to make cheese and kefir for millennia, but the ability to ferment the milk sugar lactose is found in only a few yeast species, of which the foremost is Kluyveromyces lactis [1]. Two genes, LAC12 (lactose permease) and LAC4 (lactase), are sufficient for lactose uptake and hydrolysis to glucose and galactose [2]. Here, we show that these genes have a complex evolutionary history in the genus Kluyveromyces that is likely the result of human activity during domestication.

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Background: Komagataella phaffii is a yeast widely used in the pharmaceutical and biotechnology industries, and is one of the two species that were previously called Pichia pastoris. However, almost all laboratory work on K. phaffii has utilized strains derived from a single natural isolate, CBS7435.

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We have engineered strain BG-10 of the methylotrophic yeast for use as an effective whole cell biocatalyst. We introduced into the yeast a transgene encoding a ω-transaminase for transcription in response to methanol induction. The strain was then assessed with respect to its growth performance and biotransformation of a fed ketoalcohol substrate to an amino-alcohol.

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Whole cell biocatalysis is an ideal tool for biotransformations that demand enzyme regeneration or robustness to fluctuating pH, osmolarity and biocontaminant load in feedstocks. The methylotrophic yeast Komagataella phaffii is an attractive alternative to Escherichia coli for whole cell biocatalysis due to its genetic tractability and capacity to grow to up to 60% wet cell weight by volume. We sought to exploit high cell density K.

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Interspecies hybridization is an important evolutionary mechanism in yeasts. The genus Zygosaccharomyces in particular contains numerous hybrid strains and/or species. Here, we investigated the genome of Zygosaccharomyces strain MT15, an isolate from Maotai-flavor Chinese liquor fermentation.

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We investigated genomic diversity of a yeast species that is both an opportunistic pathogen and an important industrial yeast. Under the name Candida krusei, it is responsible for about 2% of yeast infections caused by Candida species in humans. Bloodstream infections with C.

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Transketolase is a proven biocatalytic tool for asymmetric carbon-carbon bond formation, both as a purified enzyme and within bacterial whole-cell biocatalysts. The performance of Pichia pastoris as a host for transketolase whole-cell biocatalysis was investigated using a transketolase-overexpressing strain to catalyze formation of l-erythrulose from β-hydroxypyruvic acid and glycolaldehyde substrates. Pichia pastoris transketolase coding sequence from the locus PAS_chr1-4_0150 was subcloned downstream of the methanol-inducible AOX1 promoter in a plasmid for transformation of strain GS115, generating strain TK150.

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Many interspecies hybrids have been discovered in yeasts, but most of these hybrids are asexual and can replicate only mitotically. Whole-genome duplication has been proposed as a mechanism by which interspecies hybrids can regain fertility, restoring their ability to perform meiosis and sporulate. Here, we show that this process occurred naturally during the evolution of Zygosaccharomyces parabailii, an interspecies hybrid that was formed by mating between 2 parents that differed by 7% in genome sequence and by many interchromosomal rearrangements.

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Microalgae have potential as platforms for the synthesis of high-value recombinant proteins due to their many beneficial attributes including ease of cultivation, lack of pathogenic agents, and low-cost downstream processing. However, current recombinant protein levels are low compared to other microbial platforms and stable insertion of transgenes is available in only a few microalgal species. We have explored different strategies aimed at increasing growth rate and recombinant protein production in the Chlamydomonas reinhardtii chloroplast.

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