Modifications of the respiratory chain of Bacillus licheniformis as an alkalophilic and cyanide-degrading microorganism.

Bacillus licheniformis can use cyanide as a nitrogen source for its growth. However, it can also carry out aerobic respiration in the presence of this compound, a classic inhibitor of mammalian cytochrome c oxidase, indicating that B. licheniformis has a branched respiratory chain with various terminal oxidases.

Metabolic Changes and Antioxidant Response in Grown in Acetate.

is an important model to study intermediary and mitochondrial metabolism, among other processes. can grow, at very different rates, on glucose, lactate, glycerol, and ethanol as carbon sources. Under nitrogen starvation and glucose as the only carbon source, this fungus synthesizes and accumulates neutral lipids in the form of lipid droplets (LD).

The Mitochondrial Alternative Oxidase in Is Not Involved in Response to Oxidative Stress Induced by Paraquat.

It has been shown that the alternative oxidase in mitochondria of fungi and plants has important functions in the response against stress conditions, although their role in some organisms is still unknown. This is the case of . There is no evidence of the participation of the Aox1 in stressful conditions such as desiccation, high or low temperature, and low pH, among others.

Yeasts Inhabiting Extreme Environments and Their Biotechnological Applications.

Yeasts are microscopic fungi inhabiting all Earth environments, including those inhospitable for most life forms, considered extreme environments. According to their habitats, yeasts could be extremotolerant or extremophiles. Some are polyextremophiles, depending on their growth capacity, tolerance, and survival in the face of their habitat's physical and chemical constitution.

Isolation of Mitochondria from Protoplasts.

, a basidiomycete that infects , is one of the top ten fungal models for studying DNA repair, signal transduction pathways, and dimorphic transitions, among other processes. From a metabolic point of view, lacks fermentative capacity, pointing to mitochondria as a key player in central metabolism. Oxidative phosphorylation, synthesis of heme groups, Krebs cycle, β-oxidation of fatty acids, and synthesis of amino acids are some of the processes that take place in mitochondria.

Deletion of the natural inhibitory protein Inh1 in Ustilago maydis has no effect on the dimeric state of the FF-ATP synthase but increases the ATPase activity and reduces the stability.

Transduction of electrochemical proton gradient into ATP synthesis is performed by FF-ATP synthase. The reverse reaction is prevented by the regulatory subunit Inh1. Knockout of the inh1 gene in the basidiomycete Ustilago maydis was generated in order to study the function of this protein in the mitochondrial metabolism and cristae architecture.

Carbon and Nitrogen Sources Have No Impact on the Organization and Composition of Respiratory Supercomplexes.

Respiratory supercomplexes are found in mitochondria of eukaryotic cells and some bacteria. A hypothetical role of these supercomplexes is electron channeling, which in principle should increase the respiratory chain efficiency and ATP synthesis. In addition to the four classic respiratory complexes and the ATP synthase, mitochondria contain three type II NADH dehydrogenases (NADH for reduced nicotinamide adenine dinucleotide) and the alternative oxidase.

Tolerance to Oxidative Stress in Budding Yeast by Heterologous Expression of Catalases A and T from Debaryomyces hansenii.

The function of catalases A and T from the budding yeast Saccharomyces cerevisiae (ScCta1 and ScCtt1) is to decompose hydrogen peroxide (HO) to mitigate oxidative stress. Catalase orthologs are widely found in yeast, suggesting that scavenging HO is crucial to avoid the oxidative damage caused by reactive oxygen species (ROS). However, the function of catalase orthologs has not yet been experimentally characterized in vivo.

On the use of n-octyl gallate and salicylhydroxamic acid to study the alternative oxidase role.

The alternative oxidase (AOX) catalyzes the transfer of electrons from ubiquinol to oxygen without the translocation of protons across the inner mitochondrial membrane. This enzyme has been proposed to participate in the regulation of cell growth, sporulation, yeast-mycelium transition, resistance to reactive oxygen species, infection, and production of secondary metabolites. Two approaches have been used to evaluate AOX function: incubation of cells for long periods of time with AOX inhibitors or deletion of AOX gene.

Rapamycin induces morphological and physiological changes without increase in lipid content in Ustilago maydis.

The evolutionarily conserved serine/threonine kinase TOR recruits different subunits to assemble the Target of Rapamycin Complex 1 (TORC1), which is inhibited by rapamycin and regulates ribosome biogenesis, autophagy, and lipid metabolism by regulating the expression of lipogenic genes. In addition, TORC1 participates in the cell cycle, increasing the length of the G2 phase. In the present work, we investigated the effect of rapamycin on cell growth, cell morphology and neutral lipid metabolism in the phytopathogenic fungus Ustilago maydis.

Physiological changes of growth hormone during lactation in pup rats artificially reared.

During the lactation period, rat pups are fed by the dam, and the patterns of mother-pup interaction change during this period. Additionally, there are changes in feeding; first, mother´s milk is the only food needed for sustenance, and later, it is combined with solid food and water. GH serum concentrations depend on both maternal-pup interaction and energy metabolism.

Expression of alternative NADH dehydrogenases (NDH-2) in the phytopathogenic fungus .

Type 2 alternative NADH dehydrogenases (NDH-2) participate indirectly in the generation of the electrochemical proton gradient by transferring electrons from NADH and NADPH into the ubiquinone pool. Due to their structural simplicity, alternative NADH dehydrogenases have been proposed as useful tools for gene therapy of cells with defects in the respiratory complex I. In this work, we report the presence of three open reading frames, which correspond to NDH-2 genes in the genome of .

Lipid Index Determination by Liquid Fluorescence Recovery in the Fungal Pathogen Ustilago Maydis.

The article shows how to implement the LD index assay, which is a sensitive microplate assay to determine the accumulation of triacylglycerols (TAGs) in lipid droplets (LDs). LD index is obtained without lipid extraction. It allows measuring the LDs content in high-throughput experiments under different conditions such as growth in rich or nitrogen depleted media.

Lipid droplets accumulation and other biochemical changes induced in the fungal pathogen Ustilago maydis under nitrogen-starvation.

In many organisms, the growth under nitrogen-deprivation or a poor nitrogen source impacts on the carbon flow distribution and causes accumulation of neutral lipids, which are stored as lipid droplets (LDs). Efforts are in progress to find the mechanism of LDs synthesis and degradation, and new organisms capable of accumulating large amounts of lipids for biotechnological applications. In this context, when Ustilago maydis was cultured in the absence of a nitrogen source, there was a large accumulation of lipid bodies containing mainly triacylglycerols.