scholarly journals Coupling/Uncoupling Reversibility in Isolated Mitochondria from Saccharomyces cerevisiae

Life ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1307
Author(s):  
Lilia Morales-García ◽  
Carolina Ricardez-García ◽  
Paulina Castañeda-Tamez ◽  
Natalia Chiquete-Félix ◽  
Salvador Uribe-Carvajal
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Transmembrane Potential ◽  
Atp Synthesis ◽  
Ros Generation ◽  
Yeast Saccharomyces Cerevisiae ◽  
Cellular Energy ◽  
Isolated Mitochondria ◽  
Energy Needs ◽  
Uncoupling Of Oxidative Phosphorylation ◽  
Opening And Closing

The yeast Saccharomyces cerevisiae uses fermentation as the preferred pathway to obtain ATP and requires the respiratory chain to re-oxidize the NADH needed for activity of Glyceraldehyde-3-phosphate. This process is favored by uncoupling of oxidative phosphorylation (OxPhos), which is at least partially controlled by the mitochondrial unspecific pore (ScMUC). When mitochondrial ATP synthesis is needed as in the diauxic phase or during mating, a large rise in Ca2+ concentration ([Ca2+]) closes ScMUC, coupling OxPhos. In addition, ScMUC opening/closing is mediated by the ATP/ADP ratio, which indicates cellular energy needs. Here, opening and closing of ScMUC was evaluated in isolated mitochondria from S. cerevisiae at different incubation times and in the presence of different ATP/ADP ratios or varying [Ca2+]. Measurements of the rate of O2 consumption, mitochondrial swelling, transmembrane potential and ROS generation were conducted. It was observed that ScMUC opening was reversible, a high ATP/ADP ratio promoted opening and [Ca2+] closed ScMUC even after several minutes of incubation in the open state. In the absence of ATP synthesis, closure of ScMUC resulted in an increase in ROS.

scholarly journals Long Lasting Reversibility of the Mitochondrial Permeability Transition in Saccharomyces cerevisiae

2021 ◽  
Author(s):  
Lilia Morales-García ◽  
Carolina Ricardez -García ◽  
Paulina Castañeda-Tamez ◽  
Natalia Chiquete-Félix ◽  
Salvador Uribe-Carvajal
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Transmembrane Potential ◽  
Mitochondrial Permeability Transition ◽  
Energy Charge ◽  
Permeability Transition Pore ◽  
Permeability Transition ◽  
Isolated Mitochondria ◽  
Opening And Closing ◽  
Open Position

Abstract: The Saccharomyces cerevisiae mitochondrial unspecific pore (ScMUC) is an uncoupling unspecific pore that shares some similarities with the mammalian permeability transition pore (mPTP). When open, both channels deplete ion and proton gradients across the inner mitochon-drial membrane. However, the role of mPTP is to reversibly open to protect cells against stress. If mPTP remains stuck in the open position the cell dies. In contrast, ScMUC is probably dedicated to deplete oxygen from the medium in order to kill competing organisms. Such O2 depletion would be better achieved if oxidative phosphorylation is at least mildly uncoupled. Still, when oxida-tive phosphorylation is needed ScMUC should be able to close. To test this, the reversible opening and closing of ScMUC in the presence of different effectors was tested in isolated mitochondria from S. cerevisiae. Evaluations were conducted at different incubation times, monitoring the rate of O2 consumption, mitochondrial swelling and the transmembrane potential. It was observed that ScMUC did remain reversibly open for minutes. A low energy charge (ATP/ADP) closed the chan-nel. In addition, high Ca2+ promoted closing and it was a highly powerful effector.

Evolution of ethylene by Saccharomyces cerevisiae as influenced by the carbon source for growth and the presence of air

1978 ◽  
Vol 24 (6) ◽  
pp. 637-642 ◽  
Author(s):  
K. C. Thomas ◽  
Mary Spencer
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Carbon Source ◽  
Ethylene Production ◽  
Atp Synthesis ◽  
Yeast Cells ◽  
Yeast Culture ◽  
Wild Type ◽  
Yeast Saccharomyces Cerevisiae ◽  
Absolute Requirement ◽  
Wild Type Yeast

Effects of the carbon source and oxygen on ethylene production by the yeast Saccharomyces cerevisiae have been studied. The amounts of ethylene evolved by the yeast culture were less than those detected in the blank (an equal volume of uninoculated medium), suggesting a net absorption of ethylene by the yeast cells. Addition of glucose to the lactate-grown yeast culture induced ethylene production. This glucose-induced stimulation of ethylene production was inhibited to a great extent by cycloheximide. Results suggested that the yeast cells in the presence of glucose synthesized an ethylene precursor and passed it into the medium. The conversion of this precursor to ethylene might be stimulated by oxygen. The fact that ethylene was produced by the yeast growing anaerobically and also by respiration-deficient mutants isolated from the wild-type yeast suggested that mitochondrial ATP synthesis was not an absolute requirement for ethylene biogenesis.

scholarly journals Thermodynamic analysis of Saccharomyces cerevisiae growth

2019 ◽  
Author(s):  
Laura Fernandes de Almeida Meirelles ◽  
Andreas Karoly Gombert ◽  
Pedro Alcântara Pessôa Filho
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Thermodynamic Analysis ◽  
Metabolic Pathways ◽  
Atp Synthesis ◽  
Chemical Bonds ◽  
Yeast Saccharomyces Cerevisiae ◽  
Glucose Molecule ◽  
Released Energy

The yeast Saccharomyces cerevisiae is able to oxidize the glucose molecule through the metabolic pathways of fermentation and respiration, storing the released energy in the chemical bonds of the ATP molecule. However, less than half of this energy is used for ATP synthesis, supporting the hypothesis that the cell stores the spare energy in the chemical bonds of other components, in addition to releasing some of the energy in the form of heat. To verify this hypothesis, the present work validated a series of analyzes for the determination of the cell's composition, whether in relation to macromolecular and elemental components or metabolites. These analyzes will be applied in bioreactor cultivations under anaerobiosis or under aerobiosis, allowing to evaluate if the composition of the cells varies in these two conditions.

PREPARASI DEINOCOCCUS RADIODURANS DAN KHAMIR DALAM MATERIAL KECAP L-DRYING SEBAGAI BAHAN UJI PROFISIENSI

2016 ◽  
Vol 13 (1) ◽  
pp. 93
Author(s):  
Titin Yulinery ◽  
Ratih M.Dewi
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Deinococcus Radiodurans ◽  
Test Preparation ◽  
Quality Parameters ◽  
Soy Sauce ◽  
Yeast Saccharomyces Cerevisiae ◽  
Microbiological Test ◽  
Bacterial Contaminants ◽  
Minimum Number ◽  
Important Quality

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

INTERACTION OF THE HIM1 GENE PRODUCT WITH HELICASES Srs2 (RadH) AND Mph1 YEAST SACCHAROMYCES CEREVISIAE

Tsitologiya ◽  
2018 ◽  
Vol 60 (7) ◽  
pp. 555-557 ◽  
Author(s):  
E. A. Alekseeva ◽  
◽  
T. A. Evstyukhina ◽  
V. T. Peshekhonov ◽  
V. G. Korolev ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Gene Product ◽  
Yeast Saccharomyces Cerevisiae
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