Search results for "Aceto"

Cells-qPCR as a direct quantitative PCR method to avoid microbial DNA extractions in grape musts and wines.

2017

A novel quantitative PCR assay called Cells-qPCR has been developed for the rapid detection and quantification of yeasts, lactic acid bacteria (LAB) and acetic acid bacteria (AAB) directly from grape must and wine that does not require DNA extraction. The assay was tested on Brettanomyces bruxellensis, Saccharomyces cerevisiae, Lactobacillus plantarum, Oenococcus oeni, Acetobacter aceti and Gluconobacter oxydans in culture media, and in white and red grape musts and wines. Standard curves were constructed from DNA and cells for the six target species in all the matrices. Good efficiencies were obtained for both when comparing DNA and cells standard curves. No reaction inhibition was observe…

Analysis of propionate‐degrading consortia from agricultural biogas plants

2016

Abstract In order to investigate the propionate‐degrading community of agricultural biogas plants, four propionate‐degrading consortia (Ap1a, N12, G12, and Wp2a) were established from different biogas plants which were fed with renewable resources. The consortia were cultivated in a batch for a period of 2–4 years and then analyzed in an 8‐week batch experiment for microbial succession during propionate degradation. Community shifts showed considerable propagation of Syntrophobacter sulfatireducens, Cryptanaerobacter sp./Pelotomaculum sp., and “Candidatus Cloacamonas sp.” in the course of decreasing propionate concentration. Methanogenic species belonged mainly to the genera Methanosarcina,…

A Metagenomic-Based Approach for the Characterization of Bacterial Diversity Associated with Spontaneous Malolactic Fermentations in Wine

2019

This study reports the first application of a next generation sequencing (NGS) analysis. The analysis was designed to monitor the effect of the management of microbial resources associated with alcoholic fermentation on spontaneous malolactic consortium. Together with the analysis of 16S rRNA genes from the metagenome, we monitored the principal parameters linked to MLF (e.g., malic and lactic acid concentration, pH). We encompass seven dissimilar concrete practices to manage microorganisms associated with alcoholic fermentation: Un-inoculated must (UM), pied-de-cuve (PdC), Saccharomyces cerevisiae (SC), S. cerevisiae and Torulaspora delbrueckii co-inoculated and sequentially inoculated, as…

Development of enzymatically-active bacterial cellulose membranes through stable immobilization of an engineered beta-galactosidase

2018

Enzymatically-active bacterial cellulose (BC) was prepared by non-covalent immobilization of a hybrid enzyme composed by a β-galactosidase from Thermotoga maritima (TmLac) and a carbohydrate binding module (CBM2) from Pyrococcus furiosus. TmLac-CBM2 protein was bound to BC, with higher affinity at pH 6.5 than at pH 8.5 and with high specificity compared to the non-engineered enzyme. Both hydrated (HBC) and freeze-dried (DBC) bacterial cellulose showed equivalent enzyme binding efficiencies. Initial reaction rate of HBC-bound enzyme was higher than DBC-bound and both of them were lower than the free enzyme. However, enzyme performance was similar in all three cases for the hydrolysis of 5% l…

Chrysophanol- and nepodin-8-O-β-D-glucopyranoside from Rumex acetosella, the cytotoxicity towards drug sensitive and multi- drug resistant T leukaemi…

2016

Mechanistic study of the biosynthesis of R-phenylcarbinol by acetohydroxyacid synthase enzyme using hybrid quantum mechanics/molecular mechanics simu…

2021

Abstract The biosynthesis of R-phenylacetylcarbinol (R-PAC) by the acetohydroxy acid synthase, (AHAS) is addressed by molecular dynamics simulations (MD), hybrid quantum mechanics/molecular mechanics (QM/MM), and QM/MM free energy calculations. The results show the reaction starts with the nucleophilic attack of the C2α atom of the HEThDP intermediate on the Cβ atom of the carbonyl group of benzaldehyde substrate via the formation of a transition state (TS1) with the HEThDP intermediate under 4′-aminopyrimidium (APH+) form. The calculated activation free energy for this step is 17.4 kcal mol−1 at 27 °C. From this point, the reaction continues with the abstraction of Hβ atom of the HEThDP in…

Acetobacter musti sp. nov., isolated from Bobal grape must

2016

An acetic acid bacterium (strain Bo7T), obtained during a study of the microbial diversity of spontaneous fermentations of Bobal grape must, was subjected to a taxonomic study using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences allocated strain Bo7T to the genus Acetobacter, and revealed Acetobacter aceti and Acetobacter oeni to be nearest neighbours (99.57 % 16S rRNA gene sequence similarity between strain Bo7T and A. oeni CECT 5830T, and 98.76 % between strain Bo7T and A. aceti CECT 298T). Cells of strain Bo7T are Gram-negative, motile rods, catalase-positive and oxidase-negative. The DNA G+C content of strain Bo7T was 58.0 mol%. DNA–DNA hybridizations demo…

The effect of organic solvents on selected microorganisms and model liposome membrane

2019

The effect of methanol, ethanol, acetone, N,N-dimethylformamide (DMF), dimethyl sulfoxide and Nujol on the growth of Escherichia coli DH5α, Bacillus subtilis and Saccharomyces cerevisiae D273 was investigated. All of the tested cultures appeared susceptible to the organic media they were treated with, which evinced in apparent hindering of cell development. The observed diverse solvent tolerance, except from their different biochemical activity, may also be related to the changes in cell membrane fluidity induced by the solvent species. Parallel electron paramagnetic resonance investigations using egg yolk lecithin model liposomes revealed that the fluidity of the phospholipid system in cel…

Switching to intravitreal fluocinolone acetonide implant for refractory diabetic macular edema: 12- and 24-month results

2021

Purpose: To report visual and anatomical outcomes of chronic/refractory diabetic macular edema (DME) treated with intravitreal fluocinolone acetonide implant. Setting: Retrospective, one arm, multicentric study. Method: Between 2013 and 2018, 27 consecutive eyes of 25 patients with chronic/refractory DME were treated with a fluocinolone acetonide intravitreal implant. Best registered visual acuity (BRVA), central retinal thickness (CRT), and Goldmann tonometry intraocular pressure (IOP) were assessed at 12 and 24 months. The need for IOP lowering treatment as well as top-up therapy during the follow-up were also assessed. Results: The duration of DME prior to treatment in our study was 54 ±…

CCDC 2211279: Experimental Crystal Structure Determination

2023

Related Article: Anssi Peuronen, Anni Taponen, Elina Kalenius, Ari Lehtonen, Manu Lahtinen|2023|Angew.Chem.,Int.Ed.|62|e202215689|doi:10.1002/anie.202215689