The degradation of proteins in reductively [3H]methylated mitochondrial outer membrane (MOM) transplanted into cells by a poly(ethylene glycol)-mediated process has been studied. The average rate of degradation (t1/2 24-28 h) of MOM proteins transplanted into HTC cells was not the same as for endogenous MOM proteins (t1/2 56 h), mitoplast proteins (t1/2 120 h), plasma membrane proteins (t1/2 approx. 90 h) or cytosol proteins (t1/2 75 h). The degradation of transplanted MOM proteins was inhibited to the same extent (30-45%) as that of endogenous mitochondrial and plasma membrane proteins by leupeptin and NH4Cl. No inhibition of HTC cell cytosol protein degradation by NH4Cl was observed. NH4Cl differentially inhibited the degradation of endogenous MOM and mitoplast protein subunits as shown after sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. Proteins in MOM transplanted into tissue culture cells were degraded either with t1/2 24-28 h (MRC-5, B82 and A549 cells) or with t1/2 55-70 h ...
1. The respiration rate of rat liver mitochondria was stimulated by up to 70% when the extramitochondrial Ca2+ concentration was raised from 103 to 820 nM. This occurred when pyruvate, 2-oxoglutarate, or threo-(Ds)-isocitrate was employed as substrate, but not when succinate was used. 2. Ruthenium Red prevented the stimulation of mitochondrial respiration by extramitochondrial Ca2+, showing that the effect required Ca2+ uptake into the mitochondrial matrix. 3. Starvation of rats for 48 h abolished the stimulation of mitochondrial respiration by extramitochondrial Ca2+ when pyruvate was used as substrate, but did not affect the stimulation of 2-oxoglutarate oxidation by extramitochondrial Ca2+. 4. Our findings are in accord with proposals that oxidative metabolism in liver mitochondria may be stimulated by Ca2+ activation of intramitochondrial dehydrogenases. ...
TY - JOUR. T1 - Kinetics of Pi-Pi exchange in rat liver mitochondria. Rapid filtration experiments in the millisecond time range. AU - Ligeti, E.. AU - Brandolin, Gérard. AU - Dupont, Yves. AU - Vignais, Pierre V.. PY - 1985. Y1 - 1985. N2 - Phosphate-phosphate exchange through the inorganic phosphate (Pi) carrier of rat liver mitochondria was investigated by a new rapid filtration technique, which does not require the use of transport inhibitors to stop the reaction and offers high time resolution (starting from 10 ms), thus allowing kinetic measurements on a fine time scale even at room temperature. At approximately 22°C, isotopic equilibrium of [32P]Pi is achieved within 0.8-2.5 s - depending on the Pi concentration - and an initial linear phase, lasting for 400-500 ms, is observed. Complete inhibition of Pi exchange by an excess (33 nmol/mg) of mersalyl, a well-known organomercurial inhibitor, required 200 ms, pointing to the insufficiency of this reagent for effective inhibitor stop. On ...
Sigma-Aldrich offers abstracts and full-text articles by [I R Kniazeva, V V Ivanov, M A Bolshakov, L P Zharkova, A V Kereia, O P Kutenkov, V V Rostov].
The effect of cAMP on Ca²⁺ release was reinvestigated in the present study based on the findings of Lehninger et al (1978) and Christiansen (1977). Cyclic AMP caused Ca²⁺ release provided that palmitoyl CoA or palmitoylcarnitine were substrates and that the mitochondria prepared from fed rats were used within 1 hr after isolation. It was also noted in this study that the mitochondria isolated from starved rats had a lower NADH/NAD⁺ ratio and released their Ca²⁺ earlier than the mitochondria from fed rats. It was suggested that cAMP stimulates Ca²⁺ release from the mitochondria presumably by altering the redox state of the mitochondrial pyridine nucleotides.. ...
Semantic Scholar extracted view of The effect of calcium on the translocation of adenine nucleotides in rat liver mitochondria. by Armando Gómez-Puyou et al.
Although diabetes mellitus is known to be a disease associated with mitochondrial dysfunction, not everything is clear about mitochondrial Ca2+ transport and Ca2+-induced permeability transition in diabetic cells. The objective of this work was to study the operation of MCU and Ca2+-dependent mitochondrial permeabilization in the liver cells of Sprague-Dawley rats under the streptozotocin-induced type I diabetes. It was shown that two weeks after the induction of diabetes, the rate of Ca2+ uptake by the mitochondria of diabetic animals increased ~1.4-fold. The expression of MCU and MICU1 subunits did not change, yet the quantity of dominant-negative MCUb channel subunits was almost twice as lower. The organelles also became more resistant to the induction of CsA-sensitive MPT pore and less resistant to the induction of CsA-insensitive palmitate/Ca2+-induced pore. The mitochondria of diabetic liver cells also showed changes in the lipid matrix of their membranes. The content of fatty acids in the
Aubrey de Grey wrote: , [explanation as to why the proposed supplement scheme , wouldnt work, which I was vaguely able to follow] but then: , However, the more general idea that the supplementation regime in , question may have induced uncoupling of liver mitochondria is not at , all challenged by the above logic. I see no reason a priori why such , effects should not be inducible, and they would indeed make heat. The , tricky part is to alter the cells choice of which fuel to use to make , that heat, i.e. to get them to use fat in preference to dietary sugars. Why doesnt your earlier logic apply to the case of liver mitochondria? sherm ...
Analyses of supercomplex formation in the mitochondrial ETC of S. cerevisiae ISC mutants.To analyze ETC supercomplex formation, mitochondrial suspensions isolat
TY - JOUR. T1 - l-Cysteine metabolism via 3-mercaptopyruvate pathway and sulfate formation in rat liver mitochondria. AU - Ubuka, T.. AU - Ohta, Jun. AU - Yao, W. B.. AU - Abe, T.. AU - Teraoka, T.. AU - Kurozumi, Y.. PY - 1992/2. Y1 - 1992/2. N2 - We have studied the 3-mercaptopyruvate pathway (transamination pathway) of l-cysteine metabolism in rat liver mitochondria. l-Cysteine and other substrates at 10 mM concentration were incubated with mitochondrial fraction at pH 8.4, and sulfate and thiosulfate were determined by ion chromatography. When l-cysteine alone was incubated, sulfate formed was 0.7 μmol per mitochondria from one g of liver per 60 min. Addition of 2-oxoglutarate and GSH resulted in more than 3-fold increase in sulfate formation, and thiosulfate was formed besides sulfate. The sum (A + 2B) of sulfate (A) and thiosulfate (B) formed was approximately 7-times that with l-cysteine alone. Incubation with 3-mercaptopyruvate resulted in sulfate and thiosulfate formation, and sulfate ...
The β-oxidation of valproic acid (VPA; 2-n-propylpentanoic acid) was investigated in vitro in intact rat liver mitochondria incubated with 3H-labelled VPA. The metabolism of [4,5-3H2]VPA and [2-3H]VPA was studied by analysing the different acyl-CoA intermediates formed by reverse-phase HPLC with radiochemical detection. Valproyl-CoA, Δ2(E)-valproyl-CoA,3-hydroxyvalproyl-CoA and 3-oxovalproyl-CoA (labelled and non-labelled) were determined using continuous on-line radiochemical and UV detection. The formation of these intermediates was investigated using the two tritiated precursors in respiratory states 3 and 4. Valproyl-CoA was present at highest concentrations under both conditions. Two distinct labelled peaks were found, which were identified as 3H2O and [4,5-3H2]3-oxo-VPA. The formation of 3H2O strongly suggested that VPA underwent complete β-oxidation and that [4,5-3H2]3-oxo-VPA was formed by hydrolysis of the corresponding thioester. The hypothesis that 3-oxovalproyl-CoA undergoes ...
The physical properties of fish liver and rat liver mitochondria were compared as a function of temperature and osmotic pressure. The data indicate that fish mitochondria are more flexible and swell at a more rapid rate over a 0 to 30°C temperature range, whereas the rates of swelling at 30 to 40°C are comparable. The swelling rates of both fish and rat mitochondria vary with temperature and approximate the Arrhenius relationship. Apparent energies of activation for swelling averaged 26.5 kcal and 12.9 kcal for rat and fish, respectively. Fish mitochondria were less stable than rat mitochondria to osmotic variation, and the disparity in initial swelling rates became increasingly greater with lower osmotic pressure. The hypotonic swelling of both fish and rat mitochondria was readily reversed osmotically; however, there was a very rapid decay of reversal in fish mitochondria and only a very slow decay in the case of rat. All the data indicate that under comparable conditions the fish ...
Arsenic exposure mainly through food and water has been shown to be associated with increased incidence of numerous cancers and non-cancer harmful health. It is also used in cancer chemotherapy and treatment of several cancer types due to its apoptogenic effects in the various cancer and normal cell lines. We have already reported that liver is the storage site and important target organ in As (III) toxicity and recently, it has been suggested that hepatic toxicity of arsenic could be resulted from impairment of the liver mitochondria. In this study, interaction of As (III) with freshly isolated rat mitochondria was investigated. We determined different mitochondrial toxicity factors as well as mitochondrial sources of ROS formation using specific substrates and inhibitors following addition of As (III) to the mitochondria. Our results showed that arsenic (III) increased mitochondrial ROS formation, lipid peroxidation and mitochondrial membrane potential collapse, cytochrome c release and mitochondrial
Yie, H.L., Boelsterli, U.A., Lin, Q., Chung, M.C.M. (2008). Proteomics profiling of hepatic mitochondria in heterozygous Sod2+/-mice, an animal model of discreet mitochondrial oxidative stress. Proteomics 8 (3) : 555-568. [email protected] Repository. https://doi.org/10.1002/pmic. ...
Depending on the cell type, mitochondria can have very different overall structures. At one end of the spectrum, the mitochondria can resemble the standard sausage-shaped organelle pictured to the right, ranging from 1 to 4 ?m in length. At the other end of the spectrum, mitochondria can appear as a highly branched, interconnected tubular network. Observations of fluorescently labelled mitochondria in living cells have shown them to be dynamic organelles capable of dramatic changes in shape. Finally, mitochondria can fuse with one another, or split in two. The outer boundary of a mitochondrion contains two functionally distinct membranes: the outer mitochondrial membrane and the inner mitochondrial membrane. The outer mitochondrial membrane completely encloses the organelle, serving as its outer boundary. The inner mitochondrial membrane is thrown into folds, or cristae, that project inward. The cristae surface houses the machinery needed for aerobic respiration and ATP formation, and their ...
Mitochondria replicate their DNA and divide mainly in response to the energy needs of the cell. In other words, their growth and division is not linked to the cell cycle. When the energy needs of a cell are high, mitochondria grow and divide. When the energy use is low, mitochondria are destroyed or become inactive. At cell division, mitochondria are distributed to the daughter cells essentially randomly during the division of the cytoplasm. Mitochondria divide by binary fission similar to bacterial cell division; unlike bacteria, however, mitochondria can also fuse with other mitochondria.[37][52] Mitochondrial genes are not inherited by the same mechanism as nuclear genes. At fertilization of an egg cell by a sperm, the egg nucleus and sperm nucleus each contribute equally to the genetic makeup of the zygote nucleus. In contrast, the mitochondria, and therefore the mitochondrial DNA, usually comes from the egg only. The sperms mitochondria enters the egg but does not contribute genetic ...
PhosChol and Mitochondria: Depletion of phosphatidylcholine in the membranes of hepatic mitochondria is an early manifestation of decreased capacity of hepatic mitochondria to control cellular respiration, to oxidize substrates and to form high energy pho
Mitochondria are a power plants in our cell because they programme cell death. Mitochondria are also involved in signal transduction network; respond to signals from outside and emit signals themselves. Several facts have been discovered recently. First, DNA of mitochondrial code is unusual.Their DNA can be replicated, transcribed, and goes to form nucleoids. Second, Mitochondria and nuclei can communicate with each other. Nucleus communicates with mitochondria by imported proteins but still it isnt discovered how mitochondria responds back to the nucleus. Third, mitochondrion relocates protein. Inter membrane space of mitochondrial can oxidize disulphide bridges from sulfhydryl groups even though surrounded environment is highly reduced. The free energy of ATP shocks protein from mitochondrial 70-kDa heat, and it uses hydrolysis to move proteins across the mitochondrial inner membrane. Fourth, mitochondria can be divided and fused by machines, some proteins. Every two mitochondrial membranes ...
Mitochondria are usually considered to be the powerhouses of the cell and to be responsible for the aerobic production of ATP. However, many eukaryotic organisms are known to possess anaerobically functioning mitochondria, which differ significantly from classical aerobically functioning mitochondria. Recently, functional and phylogenetic studies on some enzymes involved clearly indicated an unexpected evolutionary relationship between these anaerobically functioning mitochondria and the classical aerobic type. Mitochondria evolved by an endosymbiotic event between an anaerobically functioning archaebacterial host and an aerobic α-proteobacterium. However, true anaerobically functioning mitochondria, such as found in parasitic helminths and some lower marine organisms, most likely did not originate directly from the pluripotent ancestral mitochondrion, but arose later in evolution from the aerobic type of mitochondria after these were already adapted to an aerobic way of life by losing their ...
Substantially elevated blood D-lactate (DLA) concentrations are associated with neurocardiac toxicity in humans and animals. The neurological symptoms are similar to inherited or acquired abnormalities of pyruvate metabolism. We hypothesized that DLA interferes with mitochondrial utilization of L-lactate and pyruvate in brain and heart. Respiration rates in rat brain, heart and liver mitochondria were measured using DLA, LLA and pyruvate independently and in combination. In brain mitochondria, state 3 respiration was 53% and 75% lower with DLA as substrate when compared with LLA and pyruvate, respectively (p | 0.05). Similarly in heart mitochondria, state 3 respiration was 39% and 86% lower with DLA as substrate when compared with LLA or pyruvate, respectively (p | 0.05). However, state 3 respiration rates were similar between DLA, LLA and pyruvate in liver mitochondria. Combined incubation of DLA with LLA or pyruvate markedly impaired state 3 respiration rates in brain and heart mitochondria (p | 0.05)
In sexual reproduction only the female gamete (ovum) has mitochondria when the gametes eventually fertilise, this is because the male gamete (sperm) draws upon all of its mitochondria for locomotion, to aid its travel to the ovum (egg). Furthermore, mitochondria in relation to the structure of the sperm, is wrapped tightly around the flagellum in the sperm and is fixed in this position, to enable the mitochondria to comply with the sperms unusually high ATP consumption[3]. Mitochondrion is the site of the Krebs cycle and the electron transport chain in eukaryotic organisms. It has a variable diameter from 0.5 to 1 micrometre thus can be easily seen under a light microscope. Using time-lapse micro-cinematography, it has been established that mitochondria can alter their shape continuously, and are also able to fuse and separate with other mitochondria[4]. It is surrounded by two phospholipid membranes: the outer and inner membrane. The inner membrane is folded inwards to form cristae and it is ...
Image:Mitochondrian.PNG,right,190x187px,A cross-section of a mitochondrion under an electron microscope]]Mitochondria (singular- Mitochondrion) are [[Membrane,membrane]] bound [[Organelles,organelles]] (double membrane structure), that carry out [[Oxidative phosphorylation,oxidative phosphorylation]], to produce [[ATP,ATP]]. What is more, mitochondria produce the majority of [[ATP,ATP]] used by [[Eukaryotic,eukaryotic]] [[Organism,organisms]] and are often referred to as the power houses of the [[Cell,cell]]. Furthermore, due to the fact that mitochondria are the site [[ATP synthesis,ATP synthesis]], there is often a linear relationship between the number of mitochondria in a [[Cell,cell]] and the cells [[ATP,ATP]] requirements e.g. a [[Muscle,muscle]] cell uses vast amounts of [[ATP,ATP]] and thus often contains many mitochondria to adhere to this requirement and maintain function. A further point ...
... vary in shape and size. Typical mitochondria are generally rod-shaped, having lengh 1-4 µm and breadth 0.2-1.5 µm. In some cases, these may be spherical or oval or filamentous. Mitochondria are closed sac-like structures covered by two membranes, each of which is a trilamellar lipoprotein (P-L-P) unit membrane very similar to the plasma membrane. These two membranes, called outer membrane and inner membrane, form two chambers in mitochondria. m and breadth 0.2-1.5 µm. In some cases, these may be spherical or oval or filamentous. Mitochondria are closed sac-like structures covered by two membranes, each of which is a trilamellar lipoprotein (P-L-P) unit membrane very similar to the plasma membrane. These two membranes, called outer membrane and inner membrane, form two chambers in mitochondria. m and breadth 0.2-1.5 urn. In some cases, these may be spherical or oval or filamentous ...
Abstract: Irradiation of rabbits with decimetre waves (regions of adrenal glands, liver and lower part of thigh) was accompanied by an increased content of free, biologically active corticosteroids in blood plasma due to liberation of the substances from a complex with transcortine. This phenomenon correlated with activation of the electron transport in respiratory chain of liver tissue mitochondria. The irradiation of the liver region caused distinct alteration in mitochondrial functions apparently due to intensified effect of the decimetre waves directly on the liver tissue ...
β-Estradiol (β-E), one of the chemical forms of female gonad hormone exhibited antioxidant efficacy in biochemical system, in vitro. The aim of the study was to investigate whether any other mechanism of protection by β-E to hepatic mitochondria in presence of stressor agent i.e.,a combination of Cu²⁺ and ascorbic acid is involved.Freshly prepared goat liver mitochondria was incubated with stresso ...
High levels of fructose in the diet inhibit the livers ability to properly metabolize fat. This effect is specific to fructose. Indeed, equally high levels of glucose in the diet actually improve the fat-burning function of the liver.
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Nonetheless it is conceivable that there could be aberrant mitochondria that are not damaged or free radical generating but have consequences for cellular function that can be very dangerous at specific ages. Some neurologic disorders appear to be like that, where eventually there arent enough optimal mitochondria so eventually energy failure ensues which is collapse of the proton gradient which is death. There is a strong relationship between Parkinsons and mitochondrial death, and Ive read studies highlighting how failure of transporting mitochondria back to the cell body, presumably for mitophagy, is blocked early in the development of Alzheimers, the implication being that these surviving mitochondria should have been killed but are now generating problems for the cell, if only because of inefficient energy generation and the organelles literally pile up in the axon, further inhibiting transport processes ...
The wavelength of visible light is in the range ,math,0.4-0.7 \mu m,/math,, which is at the lower end of the diameter range for mitochondria. Thus, mitochondria can be viewed with [[light microscope]]s (whose resolution is limited to ,math,0.2 \mu m,/math,) but their internal structures cannot be clearly identified. [[Electron microscope]]s need to be used to study the structure of mitochondria well ...
For a really good general article about mitochondria, click here. Some fascinating ideas are presented about how the mitochondria came to be. These ideas fit beautifully with the otherwise perplexing fact that mitochondria can respond to specific wavelengths.
styrene-co-maleic acid-co-methacrylate polymer: a polyanion that inhibits carnitine-dependent fatty acid oxidation in rat liver mitochondria
Mitochondria are present within every cell of our body, often named as intracellular power producing factories; they generate adenosine triphosphate (ATP), major energy molecule that transports chemical energy within the cell, fuelling cellular processes. Mitochondria produce about 90% of the chemical energy that cells require for survival. Mitochondria functions in a similar way to the digestive system, which takes in nutrients, breaks them down, and creates energy rich molecules for the cell.. ...
Mitochondria: The PowerHouse of the Cell Watch the following movie to review the importance of your mitochondria. Make notes to answer the following questions: Distinguish between fast and slow twitch fibers. When are they used? Which have more mitochondria? What does exercise training do for our muscle cells? What damages mitochondrial DNA? As a person…
The membranes of mitochondria are composed of lipid and proteins. The outer membrane of mitochondria contains 40% of lipids and 60% of proteins and inner membrane contains 20% of lipids and 80% of proteins. Thus, the ratio of lipid/protein in the outer membrane is 2 by 3 ratio and inner membrane is 1 by 4 ratio. Outer membrane contains a large amount of cholesterol. Inner membrane contains electron acceptors of electron transport chain and many enzymes. So, it has high contents of proteins.. ...
[The intensity of oxidative phosphorylation and the function of the adenylate system in the liver mitochondria of active and hibernating susliks Citellus undula
why is mitochondria referred to as the power plant of the cell?The mitochondria are where the electron transport chain takes place - which is used ...
Essay, Research Paper Mitochondria are the powerhouse of the cell. Their sole responsibility is to provide energy for the cell. They do this by synthesizing a molecule known as ATP, which the cell uses as energy. Mitochondria are different from the rest of the cell organelles because they contain their own DNA outside the nucleus.
Mitochondrial DNA. Mitochondria are the organelles that generate energy in most complex organisms. According to endosymbiotic theory they were originally cells similar to bacteria that were swallowed by larger cells. Like chloroplasts they have their own DNA, which codes for many of their proteins. Mitochondria contain multiple copies of each chromosome, making it harder to correct errors.. This piece was created for SynBioExpo in collaboration with Grace Mullally from the Szczelkun Lab.. ...
Learn about mitochondria and how to enhance them for better health. Mitochondria are known as the powerhouses of the cell. They are organelles that ac...
OXPHOS - this site is dedicated to mitochondria research. Theoretical and practical aspects, reagents, protocols, tools, funding agencies, databases, conferences, etc.
http://www.alscenter.org/news/newsletter/2011/August/mutants_mitochondria.html So now we SOD1 misbehaving with mitochondria (above) and astrocytes (below). http://alsn.mda.org/news/familial-sporadic-als-linked-via-astrocytes-and-sod1 Where does ubiquilin 2 fit in the grand scheme of things or is this a completely separate mutation...? How many mutations can there be? My brain hurts!
We explain Mitochondria with video tutorials and quizzes, using our Many Ways(TM) approach from multiple teachers.This lesson will discuss the structure and function of the mitochondria.
There are comments on PubPeer for publication: Inactivation of caspase-8 on mitochondria of Bcl-xL-expressing MCF7-Fas cells: role for the bifunctional apoptosis regulator protein (2002)
(Phys.org)-A team of researchers with members from France, Korea and Germany has found that temperatures inside human mitochondria can run as high as 50°C. In their paper uploaded to the preprint server bioRxiv, the group ...
Mitochondria are the cells power producers. They convert energy into forms that are usable by the cell. Located in the cytoplasm, they are the sites of
Mitochondria are having their time in the spotlight after years of being ignored. Discover everything you need to know about these cellular powerhouses.
Mitochondria ia called the power-house of the cell .It is respnsible for the production of energy in the form of ATP which is gained by digestion, absorption and respiration in the cell ...
Bod•ē TEN supports mitochondria function ... ultra-premium nutritional supplement ... enhances cellular energy, increases stamina, and reduces oxidative stress.
The respiratory organelles in the eukaryotic cells are called mitochondria. They are also called the power houses of the cells as they supply energy in the form of ATP for all metabolic activities in the cell and also in the overall organism ...
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