A New Real-Time Simple Method to Measure the Endogenous Nitrate Reductase Activity (Nar) in and Other Denitrifying Bacteria.

The transmembrane nitrate reductase (Nar) is the first enzyme in the dissimilatory alternate anaerobic nitrate respiratory chain in denitrifying bacteria. To date, there has been no real-time method to determine its specific activity embedded in its native membrane; here, we describe such a new method, which is useful with the inside-out membranes of and other denitrifying bacteria. This new method takes advantage of the native coupling of the endogenous NADH dehydrogenase or Complex I with the reduction of nitrate by Nar through the quinone pool of the inner membranes of .

In , active oxidative metabolism increases carotenoids to inactivate excess reactive oxygen species.

Carotenoids produced by bacteria, yeasts, algae and plants inactivate Free Radicals (FR). However, FR may inactivate carotenoids and even turn them into free radicals. Oxidative metabolism is a source of the highly motile Reactive Oxygen Species (ROS).

Cross-sex hormonal replacement: Some effects over mitochondria.

Transgender is a term for people whose gender identity or expression differs from their natal sex. These individuals often seek cross-hormonal therapy to simulate the individual´s desired gender. However, the use of estrogens and testosterone has side effects such as a higher propensity to cancer, weight changes and cardiovascular diseases.

Tissue-specific differences in Ca sensitivity of the mitochondrial permeability transition pore (PTP). Experiments in male rat liver and heart.

Permeability transition pore (PTP) opening dissipates ion and electron gradients across the internal mitochondrial membrane (IMM), including excess Ca in the mitochondrial matrix. After opening, immediate PTP closure must follow to prevent outer membrane disruption, loss of cytochrome c, and eventual apoptosis. Flickering, defined as the rapid alternative opening/closing of PTP, has been reported in heart, which undergoes frequent, large variations in Ca.

The mitochondrial respiratory chain from Rhodotorula mucilaginosa, an extremophile yeast.

Rhodotorula mucilaginosa survives extreme conditions through several mechanisms, among them its carotenoid production and its branched mitochondrial respiratory chain (RC). Here, the branched RC composition was analyzed by biochemical and complexome profiling approaches. Expression of the different RC components varied depending on the growth phase and the carbon source present in the medium.

Inhibitory to non-inhibitory evolution of the subunit of the FF-ATPase of and -proteobacteria as related to mitochondrial endosymbiosis.

The subunit is a potent inhibitor of the FF-ATPase of (PdFF-ATPase) and related -proteobacteria different from the other two canonical inhibitors of bacterial () and mitochondrial (IF) FF-ATPases. mimics mitochondrial IF in its inhibitory N-terminus, blocking the PdFF-ATPase activity as a unidirectional pawl-ratchet and allowing the PdFF-ATP synthase turnover. is essential for the respiratory growth of , as we showed by a knockout.

Bacteriostatic effect of Echeveria extracts on diarrheagenic E. coli pathotypes and non-cytotoxicity on human Caco-2 cells.

Introduction: Diarrheagenic Escherichia coli pathotypes are important aetiological agents of diarrhoeal illness among children from less developed areas, worldwide. Diarrheagenic E. coli pathotypes strains are increasingly becoming drug resistant, thus effective and accessible therapeutic alternatives are required for their treatment; herbal extracts may be a potential alternative.

Coupling/Uncoupling Reversibility in Isolated Mitochondria from .

The yeast 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 (MUC). When mitochondrial ATP synthesis is needed as in the diauxic phase or during mating, a large rise in Ca concentration ([Ca]) closes MUC, coupling OxPhos.

Monitoring Mitochondrial Function in C6/36 Cell Line during Dengue Virus Infection.

and mosquitoes are responsible for dengue virus (DENV) transmission in tropical and subtropical areas worldwide, where an estimated 3 billion people live at risk of DENV exposure. DENV-infected individuals show symptoms ranging from sub-clinical or mild to hemorrhagic fever. Infected mosquitoes do not show detectable signs of disease, even though the virus maintains a lifelong persistent infection.

Integrative analysis of transcriptional profile reveals LINC00052 as a suppressor of breast cancer cell migration.

Background: Long-non-coding RNAs, a class of transcripts with lengths > 200 nt, play key roles in tumour progression. Previous reports revealed that LINC00052 (long intergenic non-coding RNA 00052) was strongly downregulated during breast cancer multicellular spheroids formation and suggested a role in cell migration and oxidative metabolism.

Objective: To examine the function of LINC00052 in MCF-7 breast cancer cells.

Age-Dependent Decline in Synaptic Mitochondrial Function Is Exacerbated in Vulnerable Brain Regions of Female 3xTg-AD Mice.

Synaptic aging has been associated with neuronal circuit dysfunction and cognitive decline. Reduced mitochondrial function may be an early event that compromises synaptic integrity and neurotransmission in vulnerable brain regions during physiological and pathological aging. Thus, we aimed to measure mitochondrial function in synapses from three brain regions at two different ages in the 3xTg-AD mouse model and in wild mice.

Antimicrobial Peptide against That Activates Autophagy Is an Effective Treatment for Tuberculosis.

(MTB) is the principal cause of human tuberculosis (TB), which is a serious health problem worldwide. The development of innovative therapeutic modalities to treat TB is mainly due to the emergence of multi drug resistant (MDR) TB. Autophagy is a cell-host defense process.

Functional characterization of the mitochondrial uncoupling proteins from the white shrimp Litopenaeus vannamei.

Mitochondrial uncoupling proteins (UCPs) play an essential role in dissipating the proton gradient and controlling the mitochondrial inner membrane potential. When active, UCPs promote proton leak across the inner membrane, oxidative phosphorylation uncoupling, oxygen uptake increase and decrease the ATP synthesis. Invertebrates possess only isoforms UCP4 and UCP5, however, the role of these proteins is not clear in most species since it may depend on the physiological needs of each animal.

Metabolism, ATP production and biofilm generation by Staphylococcus epidermidis in either respiratory or fermentative conditions.

Staphylococcus epidermidis is a Gram-positive saprophytic bacterium found in the microaerobic/anaerobic layers of the skin that becomes a health hazard when it is carried across the skin through punctures or wounds. Pathogenicity is enhanced by the ability of S. epidermidis to associate into biofilms, where it avoids attacks by the host and antibiotics.

Cholesterol burden in the liver induces mitochondrial dynamic changes and resistance to apoptosis.

Non-alcoholic fatty liver disease (NAFLD) encompasses a broad spectrum of histopathological changes ranging from non-inflammatory intracellular fat deposition to non-alcoholic steatohepatitis (NASH), which may progress into hepatic fibrosis, cirrhosis, or hepatocellular carcinoma. Recent data suggest that impaired hepatic cholesterol homeostasis and its accumulation are relevant to the pathogenesis of NAFLD/NASH. Despite a vital physiological function of cholesterol, mitochondrial dysfunction is an important consequence of dietary-induced hypercholesterolemia and was, subsequently, linked to many pathophysiological conditions.

Mitochondrial activity in different regions of the brain at the onset of streptozotocin-induced diabetes in rats.

Diabetes affects a variety of tissues including the central nervous system; moreover, some evidence indicates that memory and learning processes are disrupted. Also, oxidative stress triggers alterations in different tissues including the brain. Recent studies indicate mitochondria dysfunction is a pivotal factor for neuron damage.

The role of glycolysis-derived hexose phosphates in the induction of the Crabtree effect.

Evidence for the Crabtree effect was first reported by H. Crabtree in 1929 and is defined as the glucose-induced decrease of cellular respiratory flux. This effect was observed in tumor cells and was not detected in most non-tumor cells.

Wolbachia pipientis grows in Saccharomyces cerevisiae evoking early death of the host and deregulation of mitochondrial metabolism.

Wolbachia sp. has colonized over 70% of insect species, successfully manipulating host fertility, protein expression, lifespan, and metabolism. Understanding and engineering the biochemistry and physiology of Wolbachia holds great promise for insect vector-borne disease eradication.

Alternative mitochondrial respiratory chains from two crustaceans: Artemia franciscana nauplii and the white shrimp, Litopenaeus vannamei.

Mitochondrial ATP is synthesized by coupling between the electron transport chain and complex V. In contrast, physiological uncoupling of these processes allows mitochondria to consume oxygen at high rates without ATP synthesis. Such uncoupling mechanisms prevent reactive oxygen species overproduction.

The Biological Role of the ζ Subunit as Unidirectional Inhibitor of the FF-ATPase of Paracoccus denitrificans.

The biological roles of the three natural FF-ATPase inhibitors, ε, ζ, and IF, on cell physiology remain controversial. The ζ subunit is a useful model for deletion studies since it mimics mitochondrial IF, but in the FF-ATPase of Paracoccus denitrificans (PdFF), it is a monogenic and supernumerary subunit. Here, we constructed a P.

Response of Ustilago maydis against the Stress Caused by Three Polycationic Chitin Derivatives.

Chitosan is a stressing molecule that affects the cells walls and plasma membrane of fungi. For chitosan derivatives, the action mode is not clear. In this work, we used the yeast to study the effects of these molecules on the plasma membrane, focusing on physiologic and stress responses to chitosan (CH), oligochitosan (OCH), and glycol-chitosan (GCH).

During capacitation in bull spermatozoa, actin and PLC-ζ undergo dynamic interactions.

The migration pattern of sperm-specific phospholipase C-ζ (PLC-ζ) was followed and the role of this migration in actin cytoskeleton dynamics was determined. We investigated whether PLC-ζ exits sperm, opening the possibility that PLC-ζ is the 'spermatozoidal activator factor' (SOAF). As capacitation progresses, the highly dynamic actin cytoskeleton bound different proteins to regulate their location and activity.

Key role of alternative oxidase in lovastatin solid-state fermentation.

Lovastatin is a commercially important secondary metabolite produced by Aspergillus terreus, either by solid-state fermentation or by submerged fermentation. In a previous work, we showed that reactive oxygen species (ROS) accumulation in idiophase positively regulates lovastatin biosynthetic genes. In addition, it has been found that lovastatin-specific production decreases with aeration in solid-state fermentation (SSF).

The Cox1 C-terminal domain is a central regulator of cytochrome oxidase biogenesis in yeast mitochondria.

Cytochrome oxidase (CO) is the last electron acceptor in the respiratory chain. The CO core is formed by mitochondrial DNA-encoded Cox1, Cox2, and Cox3 subunits. Cox1 synthesis is highly regulated; for example, if CO assembly is blocked, Cox1 synthesis decreases.