Publications by authors named "LE Simone"

The chapter describes the bioconversion of phytosterols into androstenedione (AD) by Mycolicibacterium spp. in shake flasks and fermenters, as well as LC-MS-based methods for analysis of phytosterols and steroid products. Phytosterols are derived as by-products of vegetable oil refining and manufacture of wood pulp.

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This chapter describes methods for cultivation and characterization of the growth of Mycolicibacterium spp. mutants in a microbioreactor system in the presence of steroids and/or phytosterols followed by high-throughput mass spectrometry analysis to describe their ability to convert phytosterols into the target steroid androstenedione (AD). We focus on Mycolicibacterium neoaurum NRRL B-3805 ΔkstD which can convert phytosterol into androstenedione (AD) as one of its major steroid products, and mutants thereof with increased tolerance towards this end-product.

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The use of methanol as carbon source for biotechnological processes has recently attracted great interest due to its relatively low price, high abundance, high purity, and the fact that it is a non-food raw material. In this study, methanol-based production of 5-aminovalerate (5AVA) was established using recombinant strains. 5AVA is a building block of polyamides and a candidate to become the C5 platform chemical for the production of, among others, δ-valerolactam, 5-hydroxy-valerate, glutarate, and 1,5-pentanediol.

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Crude glycerol is an important by-product of the biodiesel industry, which can be converted into volatile fatty acids (VFA) and/or 1,3-propanediol (1,3-PDO) by fermentation. In this study, a selective conversion of VFA to polyhydroxyalkanoates (PHA) was attained while leaving 1,3-PDO in the supernatant by means of mixed microbial consortia selection strategies. The process showed highly reproducible results in terms of PHA yield, 0.

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Crude glycerol, a by-product from the biodiesel industry, can be converted by mixed microbial consortia into 1,3-propanediol (1,3-PDO) and volatile fatty acids. In this study, further conversion of these main products into polyhydroxyalkanoates (PHA) was investigated with the focus on 1,3-PDO. Two different approaches for the enrichment of PHA accumulating microbial consortia using an aerobic dynamic feeding strategy were applied.

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Lytic polysaccharide monooxygenases (LPMOs) are key enzymatic players of lignocellulosic biomass degradation processes. As such, they have been introduced in cellulolytic cocktails for more efficient and less expensive lignocellulose saccharification. The recombinant production of LPMOs in bacteria for scientific investigations using vectors typically based on the T7 and lacUV5 promoters has been hampered by low yields.

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D-Ribulose-5-phosphate-3-epimerase (RPE) and 6-phosphofructokinase (PFK) catalyse two reactions in the ribulose monophosphate (RuMP) cycle in Bacillus methanolicus. The B. methanolicus wild-type strain MGA3 possesses two putative rpe and pfk genes encoded on plasmid pBM19 (rpe1-MGA3 and pfk1-MGA3) and on the chromosome (rpe2-MGA3 and pfk2-MGA3).

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is a thermophilic methylotroph able to overproduce amino acids from methanol, a substrate not used for human or animal nutrition. Based on our previous RNA-seq analysis a mannitol inducible promoter and a putative mannitol activator gene were identified. The mannitol inducible promoter was applied for controlled gene expression using fluorescent reporter proteins and a flow cytometry analysis, and improved by changing the -35 promoter region and by co-expression of the regulator gene.

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The 5' and 3' untranslated regions (UTRs) of messenger RNAs (mRNAs) function as platforms that can determine the fate of each mRNA individually and in aggregate. Multiple mRNAs that encode proteins that are functionally related often interact with RNA-binding proteins (RBPs) and noncoding RNAs (ncRNAs) that coordinate their expression in time and space as RNA regulons within the ribonucleoprotein (RNP) infrastructure we term the ribonome. Recent ribonomic methods have emerged that can determine which mRNAs are bound and regulated by RBPs and ncRNAs, some of which act in combination to determine global outcomes.

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