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741.
Huijie Wang Annick Le Clainche Marie-Thrse Le Dall Yves Wache Yves Pagot Jean-Marc Belin Claudie Gaillardin Jean-Marc Nicaud 《Yeast (Chichester, England)》1998,14(15):1373-1386
The ACO3 gene, which encodes one of the acyl-CoA oxidase isoenzymes, was isolated from the alkane-utilizing yeast Yarrowia lipolytica as a 10 kb genomic fragment. It was sequenced and found to encode a 701-amino acid protein very similar to other ACOs, 67·5% identical to Y. lipolytica Aco1p and about 40% identical to S. cerevisiae Pox1p. Haploid strains with a disrupted allele were able to grow on fatty acids. The levels of acyl-CoA oxidase activity in the ACO3 deleted strain, in an ACO1 deleted strain and in the wild-type strain, suggested that ACO3 encodes a short chain acyl-CoA oxidase isoenzyme. This narrow substrate spectrum was confirmed by expression of Aco3p in E. coli. © 1998 John Wiley & Sons, Ltd. 相似文献
742.
Dominique Druaux Georges Mangeot Anne Endrizzi Jean-Marc Belin 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1997,68(2):214-218
The biotransformation of four alcohol substrates (butanol, 2-methylbutanol, 3-methylbutanol and 2-phenylethanol) into their acids was studied using a strain of Acetobacter aceti. Bioconversion yields depended on the molecular structure of the alcohol. Biotransformation of high concentrations of alcohols was possible until the precursor reached an inhibiting concentration (3·8 g dm−3 for butanol and 3-methylbutanol, 4·2 g dm−3 for 2-methylbutanol). In contrast, biotransformation of 2-phenylethanol decreased when alcohol concentration was higher than 0·3 g dm−3. Dissolved oxygen concentrations and pH conditions of the medium were important factors in improving bioconversion. Transformation of 2-methylbutanol into the corresponding acid was increased when dissolved oxygen partial pressure increased from 60 to 80% and regulation at pH 6 allowed an increase in the production of butyric acid from butanol. © 1997 SCI. 相似文献
743.
Marco Bertani Nicolas Bisbrouck Jean-Marc Delaye Frédéric Angeli Alfonso Pedone Thibault Charpentier 《Journal of the American Ceramic Society》2023,106(9):5501-5521
Classical molecular dynamics simulations have been used to investigate the structural role of Mg and its effect when it is incorporated in sodium aluminoborosilicate glasses. The simulations have been performed using three interatomic potentials; one is based on the rigid ionic model parameterized by Wang et al. (2018) and two slightly different parameterization of the core–shell model provided by Stevensson et al. (2018) and Pedone et al. (2020) The accuracies of these models have been assessed by detailed structural analysis and comparing the simulated nuclear magnetic resonance (NMR) spectra for spin active nuclei (29Si, 27Al, 11B, 17O, 25Mg, and 23Na) with the experimental counterparts collected in a previous work. Our simulations reveal that the core–shell parameterizations provide better structural models. In fact, they better reproduce the NMR spectra of all the investigated nuclei and give better agreement with known experimental data. Magnesium is found to be five coordinated on average with distances with oxygen in between a network modifier (like Na) and an intermediate network formed (like Al). It prefers to lay closer to three-coordinated B atoms, forming B–NBO bonds, with respect to Si and especially Al. This can explain the formation of AlO5 and AlO6 units in the investigated Na-free glass, together with a Si clusterization. 相似文献
744.