scholarly journals Electromagnetic Fields (0.04 to 0.39) mT effect on cellular growth cycles of Saccharomyces cerevisiae wine strains

2019 ◽  
Vol 17 (2) ◽  
pp. 196
Author(s):  
Eliseo Amado-González ◽  
Alveiro Álvarez Ovallos ◽  
Alfonso Quijano Parra

Low frecuency electromagnetic fields effect (EMF) on growth cycles of yeast Saccharomyces cerevisiae wine strains Rv1 and Rhône were studied.  A cylindrical coil induced magnetic fields with inductions up to 0,39 mT. Exposure time to EMF varied between (1 – 10) min at 30 °C.  The biomass growth were monitored in the reactor culture media (yeast extract + by measurement optical density from (0 to 32) h. The biomass was found by dry weight. After yeast expose to the different EMF, the number of growth cycles decreased from 4 cycles to 2 or 1. However, the biomass production increased almost 50 %.  The best biomass production was found at 0.39 mT and 10 min exposure time.  Keywords: Electromagnetic fields, Saccharomyces cerevisiae, biomass production, RV1

2021 ◽  
Author(s):  
Mahsa Babaei ◽  
Luisa Sartori ◽  
Alexey Karpukhin ◽  
Dmitrii Abashkin ◽  
Elena Matrosova ◽  
...  

Abstract Biotechnological production requires genetically stable recombinant strains. To ensure genomic stability, recombinant DNA is commonly integrated into the genome of the host strain. Multiple genetic tools have been developed for genomic integration into baker's yeast Saccharomyces cerevisiae. Previously, we had developed a vector toolkit EasyClone-MarkerFree for stable integration into eleven sites on chromosomes X, XI, and XII of S. cerevisiae. The markerless integration was enabled by CRISPR-Cas9 system. In this study, we have expanded the kit with eight additional intergenic integration sites located on different chromosomes. The integration efficiency into the new sites was above 80%. The expression level of green fluorescence protein (gfp) for all eight sites was similar or above XI-2 site from the original EasyClone-MarkerFree toolkit. The cellular growth was not affected by the integration into any of the new eight locations. The eight-vector expansion kit is available from AddGene.


2020 ◽  
Vol 12 (20) ◽  
pp. 8389
Author(s):  
Hassan-Sibroe A. Daanaa ◽  
Mennatullah Abdou ◽  
Hanan A. Goda ◽  
Mohamed T. Abbas ◽  
Mervat A. Hamza ◽  
...  

Although plant-based culture media enhances in vitro cultivation of rhizobacteria, studies assessing their biomass potential for large-scale applications are lacking. Here, we advance plant pellets (PPs) as a novel technology to unlock the potential of such vegan culture media for biomass production of Rhizobium leguminosarum. PP formulations were based on mixtures of Egyptian clover powder and the agro-byproducts glycerol and molasses. These mixtures were either contained or not contained in teabags during culture media preparation. Metrics of biomass included colony forming units, optical density (OD600nm), and cell dry weight (DW). Biomass comparisons between culture media based on PPs and standard yeast extract mannitol (YEM) revealed that the following PPs composition, contained in teabags, cultivated rhizobia at levels comparable to YEM: 16 g clover powder, 5% molasses, and 0.8% glycerol. This PPs composition enabled shorter generation times of rhizobia (PP: 3.83 h, YEM: 4.28 h). Strikingly, PPs mixtures supplemented with 10% molasses and not contained in teabags promoted rhizobia without apparent lag phases and produced 25% greater DW than YEM. PPs potentiate the use of dehydrated vegan feedstocks for both plant microbiota cultivation and biomass production and appear as cost- and labor-effective tools, easy to handle and store for plant-based culture media preparation.


Author(s):  
M Lairón-Peris ◽  
S. J. Routledge ◽  
J. A. Linney ◽  
J Alonso-del-Real ◽  
C.M. Spickett ◽  
...  

Saccharomyces cerevisiae is an important unicellular yeast species within the biotechnological and food and beverage industries. A significant application of this species is the production of ethanol, where concentrations are limited by cellular toxicity, often at the level of the cell membrane. Here, we characterize 61 S. cerevisiae strains for ethanol tolerance and further analyse five representatives with varying ethanol tolerances. The most tolerant strain, AJ4, was dominant in co-culture at 0% and 10% ethanol. Unexpectedly, although it does not have the highest NIC or MIC, MY29 was the dominant strain in co-culture at 6% ethanol, which may be linked to differences in its basal lipidome. Whilst relatively few lipidomic differences were observed between strains, a significantly higher PE concentration was observed in the least tolerant strain, MY26, at 0% and 6% ethanol compared to the other strains that became more similar at 10%, indicating potential involvement of this lipid with ethanol sensitivity. Our findings reveal that AJ4 is best able to adapt its membrane to become more fluid in the presence of ethanol and lipid extracts from AJ4 also form the most permeable membranes. Furthermore, MY26 is least able to modulate fluidity in response to ethanol and membranes formed from extracted lipids are least leaky at physiological ethanol concentrations. Overall, these results reveal a potential mechanism of ethanol tolerance and suggests a limited set of membrane compositions that diverse yeast species use to achieve this. Importance Many microbial processes are not implemented at the industrial level because the product yield is poorer and more expensive than can be achieved by chemical synthesis. It is well established that microbes show stress responses during bioprocessing, and one reason for poor product output from cell factories is production conditions that are ultimately toxic to the cells. During fermentative processes, yeast cells encounter culture media with high sugar content, which is later transformed into high ethanol concentrations. Thus, ethanol toxicity is one of the major stresses in traditional and more recent biotechnological processes. We have performed a multilayer phenotypic and lipidomic characterization of a large number of industrial and environmental strains of Saccharomyces to identify key resistant and non-resistant isolates for future applications.


Author(s):  
Anna Ylinen ◽  
Hannu Maaheimo ◽  
Adina Anghelescu-Hakala ◽  
Merja Penttilä ◽  
Laura Salusjärvi ◽  
...  

Abstract Polyhydroxyalkanoates (PHA) provide biodegradable and bio-based alternatives to conventional plastics. Incorporation of 2-hydroxy acid monomers into polymer, in addition to 3-hydroxy acids, offers possibility to tailor the polymer properties. In this study, poly(D-lactic acid) (PDLA) and copolymer P(LA-3HB) were produced and characterized for the first time in the yeast Saccharomyces cerevisiae. Expression of engineered PHA synthase PhaC1437Ps6–19, propionyl-CoA transferase Pct540Cp, acetyl-CoA acetyltransferase PhaA, and acetoacetyl-CoA reductase PhaB1 resulted in accumulation of 3.6% P(LA-3HB) and expression of engineered enzymes PhaC1Pre and PctMe resulted in accumulation of 0.73% PDLA of the cell dry weight. According to NMR, P(LA-3HB) contained D-Lactic acid repeating sequences. For reference, expression of PhaA, PhaB1, and PHA synthase PhaC1 resulted in accumulation 11% poly(hydroxybutyrate) (PHB) of the cell dry weight. Weight average molecular weights of these polymers were comparable to similar polymers produced by bacterial strains, 24.6 kDa, 6.3 kDa, and 1 130 kDa, for P(LA-3HB), PDLA, and PHB, respectively. The results suggest that yeast, as a robust and acid tolerant industrial production organism, could be suitable for production of 2-hydroxy acid containing PHAs from sugars or from 2-hydroxy acid containing raw materials. Moreover, the wide substrate specificity of PHA synthase enzymes employed increases the possibilities for modifying copolymer properties in yeast in the future.


2021 ◽  
Author(s):  
Manuella Silverio ◽  
Rosane Piccoli ◽  
João Reis ◽  
José Gregorio Gomez ◽  
Antonio Baptista

Abstract The Brazilian ethanol industry is one of the most important in the global market, however these important industrial activities have been generating significant amounts of vinasse and its management has become costly for distilleries. In this study, the aim was to evaluate concentrated and in natura vinasse as basal culture media for biotechnological processes. Different bacteria and processes were assessed: L-threonine production by E. coli THR14, with glucose as carbon source; PHB production by halophilic strain Halomonas sp. HG03, with sucrose as carbon source; and PHB biosynthesis by R. eutropha L359PCJ, which used glycerol from vinasse as carbon source. Strains were evaluated firstly in shake flasks cultivations using vinasse-based media. E. coli THR14 had no statistical difference for biomass and L-threonine concentrations among control and vinasse-based treatments (up to 50% v v-1 of in natura vinasse). Halomonas sp. HG03 and R. eutropha L359PCJ were cultivated in mineral media diluted by in natura (50% and 75% v v-1) and concentrated (50% and 75% v v-1) vinasses. Higher vinasse concentrations resulted in higher cellular growth rather than PHB accumulation for both bacteria. In vinasse-based treatments, Halomonas sp. HG03 had PHB content between 19.6 – 75.2% and R. eutropha L359PCJ, 48.4 – 68.5%. 50% (v v-1) of concentrated vinasse was the most attractive condition for PHB production by both bacteria. Further experiments in CSTR bioreactors used this nutritional condition and R. eutropha L359PCJ had PHB content of 66.3%, concentrations of residual cell dry weight (rCDW) = 9.4 g L-1 and PHB = 18.6 g L-1, with YX/S = 0.16 g gGLYCEROL-1, YP/S = 0.32 g gGLYCEROL-1 and 0.25 gPHB Lh-1. Halomonas sp. HG03 had PHB content of 45.7%, rCDW = 9.8 g L-1, PHB = 8.3 g L-1 and YX/S = 0.18 g gSUCROSE-1, YP/S = 0.16 g gSUCROSE-1 and 0.12 gPHB Lh-1. Finally, cost reductions of PHB production by R. eutropha L359PCJ with concentrated vinasse-based medium were evaluated in silico by using SuperPro Designer. As a partial source of glycerol and other nutrients for PHB production by R. eutropha L359PCJ, vinasse reduced overall production costs by 13%. Simulated processes that used concentrated vinasse-based media combined with improvements of PHB productivity and higher cellular densities had production costs between US$ 3.9 – 7.5/kgPHB and 2.6 – 7.3 years of payback time.


2020 ◽  
Author(s):  
Zahra Fathi ◽  
Larissa Ribeiro Ramos Tramontin ◽  
Gholamhossein Ebrahimipour ◽  
Irina Borodina ◽  
Farshad Darvishi

Abstract β-Carotene is a yellow-orange-red pigment used in food, cosmetics, and pharmacy. There is no commercial yeast-based process for β-carotene manufacturing. In this work, we engineered the baker's yeast Saccharomyces cerevisiae by expression of lipases and carotenogenic genes to enable the production of β-carotene on hydrophobic substrates. First, the extracellular lipase (LIP2) and two cell-bound lipases (LIP7 and LIP8) from oleaginous yeast Yarrowia lipolytica were expressed either individually or in combination in S. cerevisiae. The engineered strains could grow on olive oil and triolein as the sole carbon source. The strain expressing all three lipases had ∼40% lipid content per dry weight. Next, we integrated the genes encoding β-carotene biosynthetic pathway, crtI, crtYB, and crtE from Xanthophyllomyces dendrorhous. The resulting engineered strain bearing the lipases and carotenogenic genes reached a titer of 477.9 mg/L β-carotene in yeast peptone dextrose medium supplemented with 1% (v/v) olive oil, which was 12-fold higher than an analogous strain without lipases. The highest β-carotene content of 46.5 mg/g DCW was obtained on mineral medium supplemented with 1% (v/v) olive oil. The study demonstrates the potential of applying lipases and hydrophobic substrate supplementation for the production of carotenoids in S. cerevisiae.


2016 ◽  
Vol 13 (1) ◽  
pp. 93
Author(s):  
Titin Yulinery ◽  
Ratih M.Dewi

Tes kemampuan adalah salah satu kegiatan penting dalam pengendalian mutu dan jaminan kualitas mikrobiologi laboratorium untuk mengukur kompetensi analis dan analisis uji profisiensi membutuhkan persiapan Model mikroorganisme adalah kualitas standar dan validitas. Mikrobiologi uji kualitas produk kedelai utama diarahkan pada kehadiran Saccharomyces cerevisiae ragi (S. cerevisiae), S. Bailli, S. rouxii dankontaminan bakteri seperti Bacillus dan Deinococcus. Jenis ragi dan bakteri yang terlibat dalam proses dan dapat menjadi salah satu parameter kualitas penting dalam persiapan yang dihasilkan. Jumlah dan viabilitas bakteri dan ragi menjadi parameter utama dalam proses persiapan bahan uji. Jumlah tersebut adalah jumlah minimum yang berlaku dapat dianalisis. Jumlah ini harus dibawah 10 CFU diperlukan untuk menunjukkan tingkat hygienitas proses dan tingkat minimal kontaminasi. Viabilitas bakteri dan bahan tes ragi persiapan untuk tes kemahiran kecap yang diawetkan dengan L-pengeringan adalah teknik Deinococcus radiodurans (D. radiodurans) 16 tahun, 58 tahun S. cerevisiae, dan S. roxii 13 tahun. kata kunci: Viabilitas, Deinococcus, khamir, L-pengeringan, Proficiency AbstractProficiency test is one of the important activities in quality control and quality assurance microbiology laboratory for measuring the competence of analysts and analysis Proficiency test requires a model microorganism preparations are standardized quality and validity. Microbiological test of the quality of the main soy products aimed at thepresence of yeast Saccharomyces cerevisiae (S. cerevisiae), S. bailli, S. rouxii and bacterial contaminants such as Bacillus and Deinococcus. Types of yeasts and bacteria involved in the process and can be one of the important quality parameters in the preparation produced. The number and viability of bacteria and yeasts become themain parameters in the process of test preparation materials. The amount in question is the minimum number that is valid can be analyzed. This amount must be below 10 CFU required to indicate the level of hygienitas process and the minimum level of contamination. Viability of bacteria and yeast test preparation materials for proficiencytest of soy sauce that preserved by L-drying technique is Deinococcus radiodurans ( D. radiodurans ) 16 years, 58 years S. cerevisiae, and S. roxii 13 years. key words : Viability, Deinococcus, Khamir, L-drying, Proficiency


Sign in / Sign up

Export Citation Format

Share Document