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PdY is alpha-derived structured and crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Y is bonded in a 7-coordinate geometry to seven equivalent Pd atoms. There are a spread of Y–Pd bond distances ranging from 2.95–3.01 Å. Pd is bonded in a 7-coordinate geometry to seven equivalent Y atoms.
In this study we demonstrate that transgenic Lipomyces starkeyi strains expressing a ?-zingiberene synthase gene from Lemon basil or Hall’s panicgrass can produce up to 17 mg/l of ?-zingiberene in yeast extract peptone dextrose (YPD) medium containing 4% glucose. Following these findings, the transgenic strain was examined in 8% glucose media with C/N ratios of 20 or 80, and YPD. YPD medium resulted in 59.2 mg/l??-zingiberene accumulation. We further improved ?-zingiberene production by over-expression of selected genes from mevalonate pathway and achieved 145% improvement in ?-zingiberene synthesis. The growth medium was optimized for ?-zingiberene production, which resulted in 14.9% higher titer than YPD medium. The final transgenic strain produced 700 mg/l ?-zingiberene in fed-batch bioreactor culture. This study opens a new synthetic route to produce ?-zingiberene or other terpenoids in the oleaginous yeast L. starkeyi and establishes this yeast as a platform for jet fuel biosynthesis.
Abstract Hanseniaspora guilliermondii is a well-recognized producer of acetate esters associated with fruity and floral aromas. The molecular mechanisms underneath this production or the environmental factors modulating it remain unknown. Herein, we found that, unlike Saccharomyces cerevisiae, H. guilliermondii over-produces acetate esters and higher alcohols at low carbon-to-assimilable nitrogen (C:N) ratios, with the highest titers being obtained in the amino acid-enriched medium YPD. The evidences gathered support a model in which the strict preference of H. guilliermondii for amino acids as nitrogen sources results in a channeling of keto-acids obtained after transamination to higher alcohols and acetate esters. This higher production was accompanied by higher expression of the four HgAATs, genes, recently proposed to encode alcohol acetyl transferases. In silico analyses of these HgAat’s reveal that they harbor conserved AATs motifs, albeit radical substitutions were identified that might result in different kinetic properties. Close homologues of HgAat2, HgAat3, and HgAat4 were only found in members of Hanseniaspora genus and phylogenetic reconstruction shows that these constitute a distinct family of Aat’s. These results advance the exploration of H. guilliermondii as a bio-flavoring agent providing important insights to guide future strategies for strain engineering and media manipulation that can enhance production of aromatic volatiles.
Abstract The pathogenic yeast, Candida albicans, and other microbes must be able to handle drastic changes in nutrient availability within the human host. Copper, iron, and phosphate are essential micronutrients for microbes that are sequestered by the human host as nutritional immunity; yet high copper levels are employed by macrophages to induce toxic oxidative stress. Grf10 is a transcription factor important for regulating genes involved in morphogenesis (filamentation, chlamydospore formation) and metabolism (adenylate biosynthesis, 1-carbon metabolism). The grf10Δ mutant exhibited resistance to excess copper in a gene dosage-dependent manner but grew the same as the wild type in response to other metals (calcium, cobalt, iron, manganese, and zinc). Point mutations in the conserved residues D302 and E305, within a protein interaction region, conferred resistance to high copper and induced hyphal formation similar to strains with the null allele. The grf10Δ mutant misregulated genes involved with copper, iron, and phosphate uptake in YPD medium and mounted a normal transcriptional response to high copper. The mutant accumulated lower levels of magnesium and phosphorus, suggesting that copper resistance is linked to phosphate metabolism. Our results highlight new roles for Grf10 in copper and phosphate homeostasis in C. albicans and underscore the fundamental role of Grf10 in connecting these with cell survival.
These data are associated with a larger project to understand grown and metabolism of yeast on a xylose media under anaerobic conditions. Strains delta-ira2, delta-bcy1, and delta-ira2bcy1 are being evaluated for differences in lipid abundances on normal (YPD) and xylose (YPX) media. [doi:10.25345/C5M32NF7Z]
RNA-seq and transcriptome analysis of 4 strains (BY4743, BC187, NCYC3290, and YPS128) that were grown in YPD+ 0.7M NaCl. For each strain, 3 samples were collected: T0 (unstressed cells), T30 (30 mins after cells placed in 0.7M NaCl), and T3h (3 hours after cells placed in NaCl). These strains were collected in 3 biological replicates. The library for sample YPS128 Rep 3 T30 failed so this sample is missing and there are a total of 35 samples in the dataset.