Co-evolution of large inverted repeats and G-quadruplex DNA in fungal mitochondria may facilitate mitogenome stability: the case of Malassezia.

Mitogenomes are essential due to their contribution to cell respiration. Recently they have also been implicated in fungal pathogenicity mechanisms. Members of the basidiomycetous yeast genus Malassezia are an important fungal component of the human skin microbiome, linked to various skin diseases, bloodstream infections, and they are increasingly implicated in gut diseases and certain cancers.

The imaginative dimension of digital disinformation: Fake news, political trolling, and the entwined crises of Covid-19 and inter-Asian racism in a postcolonial city.

This article uses the concept of the 'imaginative dimension of digital disinformation' to explore how inter-Asian racism in a postcolonial city matters to the way people engage with racially tinged Covid-19 digital disinformation. It pays attention to two key socialities that fake news and political trolling online seek to weaponise: people's existing social narratives as well as their relationally embedded practices of media consumption. Drawing on 15 life story interviews with locals from the Philippines capital of Manila, this article characterises their interpretations of online disinformation campaigns that aim to amplify their shared social narrative of resentment towards China and bank on their communicative practices surrounding this.

Betalain health-promoting effects after ingestion in Caenorhabditis elegans are mediated by DAF-16/FOXO and SKN-1/Nrf2 transcription factors.

Betalain-rich extracts have been used for many years by their nutraceutical potential. However, the study of their bioactivities has always been hampered by their difficult obtention. To explain their mode of action, seventeen pure betalains were tested in vivo using the animal model C.

An uncharacterized FMAG_01619 protein from Fusobacterium mortiferum ATCC 9817 demonstrates that some bacterial macrodomains can also act as poly-ADP-ribosylhydrolases.

Macrodomains constitute a conserved fold widely distributed that is not only able to bind ADP-ribose in its free and protein-linked forms but also can catalyse the hydrolysis of the latter. They are involved in the regulation of important cellular processes, such as signalling, differentiation, proliferation and apoptosis, and in host-virus response, and for this, they are considered as promising therapeutic targets to slow tumour progression and viral pathogenesis. Although extensive work has been carried out with them, including their classification into six distinct phylogenetically clades, little is known on bacterial macrodomains, especially if these latter are able to remove poly(ADP-ribose) polymer (PAR) from PARylated proteins, activity that only has been confirmed in human TARG1 (C6orf130) protein.

Biochemical characterization of a new nicotinamidase from an unclassified bacterium thriving in a geothermal water stream microbial mat community.

Nicotinamidases are amidohydrolases that convert nicotinamide into nicotinic acid, contributing to NAD+ homeostasis in most organisms. In order to increase the number of nicotinamidases described to date, this manuscript characterizes a nicotinamidase obtained from a metagenomic library fosmid clone (JFF054_F02) obtained from a geothermal water stream microbial mat community in a Japanese epithermal mine. The enzyme showed an optimum temperature of 90°C, making it the first hyperthermophilic bacterial nicotinamidase to be characterized, since the phylogenetic analysis of this fosmid clone placed it in a clade of uncultured geothermal bacteria.

Characterization of betalains, saponins and antioxidant power in differently colored quinoa (Chenopodium quinoa) varieties.

Quinoa was the traditional grain crop used by the prehispanic civilizations in America. Grains are white, black, yellow, and red-violet and plants are cultivated in vast areas of Peru, Bolivia and Ecuador. The recent description of the betacyanin pigment betanin in red-violet varieties is here further analyzed detecting the presence of amaranthin not previously identified in quinoa grains.

One-step synthesis of betalains using a novel betalamic acid derivatized support.

Betalains are plant pigments with high antioxidant and cancer chemopreventive properties used by the food industry as safe colorants. Betalains are restricted to species of the order Caryophyllales, and difficulty in obtaining individual molecules has limited their structural identification and application. This study was designed to develop a betalamic acid derivatized support generated from a primary amine polymer.

Encapsulation of the most potent antioxidant betalains in edible matrixes as powders of different colors.

Betalains are plant pigments with high antioxidant and free radical scavenging activities. While basal activity exists in all betalains, the dihydroxylated molecules present the highest TEAC values of the family of compounds. However, their lability limits possible applications.

Stabilization of the bioactive pigment of opuntia fruits through maltodextrin encapsulation.

Betalains are water-soluble, nitrogen-containing pigments of growing interest in the food industry. They are present in most plants belonging to the order Caryophyllales, where they fulfill the role of anthocyanins, and are divided into two groups: violet betacyanins and yellow betaxanthins. They are bioactive molecules that account for health-promoting properties, recently described for cactus pears (Opuntia).

A continuous spectrophotometric assay for determination of the aureusidin synthase activity of tyrosinase.

Introduction: Aurones (aureusidin glycosides) are plant flavonoids that provide yellow colour to the flowers of some ornamental plants. In this study we analyse the capacity of tyrosinase to catalyse the synthesis of aureusidin by tyrosinase from the chalcone THC (2',4',6',4-tetrahydroxychalcone).

Objective: To develop a simple continuous spectrophotometric assay for the analysis of the spectrophotometric and kinetic characteristics of THC oxidation by tyrosinase.

[The current health system and the spirit of May 68].

Forty years after the 68 May revolt, we have thought of interest to retrieve part of the revolutionary ideology concerning the role of medical practice in the society they would to change. In essence they said: the current organization of health care, although masked by mysticism, provides political support to the dominant class and favours socio-economic exploitation. Relevant features of medical structures, the hospital, the traditional medical mentality, the biologistic paradigm, etc.

Fluorescence detection of tyrosinase activity on dopamine-betaxanthin purified from Portulaca oleracea (common purslane) flowers.

Tyrosinase or polyphenol oxidase (EC 1.14.18.

Partial purification of latent polyphenol oxidase from peach (Prunus persica L. Cv. Catherina). Molecular properties and kinetic characterization of soluble and membrane-bound forms.

This paper analyzes the kinetic and structural characteristics of polyphenol oxidase (PPO) from peach cv. Catherina. The PPO was obtained in a latent state in both the soluble and membrane-bound forms, and both forms were activated by acid shock and the detergent SDS.

Oxidation of the flavonoid eriodictyol by tyrosinase.

A pathway is proposed for the oxidation of the flavonoid eriodictyol by mushroom tyrosinase. In it, the enzymatic oxidation of eriodictyol leads to the formation of eriodictyol-o-quinone, which undergoes the nucleophilic attack of another eriodictyol unit to yield a dimer. This dimer is then oxidized by the eriodictyol-o-quinone.

Differential activation of a latent polyphenol oxidase mediated by sodium dodecyl sulfate.

A kinetic study of the activity of soluble and membrane-bound latent polyphenol oxidase (PPO) extracted from beet root (Beta vulgaris) was carried out. For the first time, two types of behavior (hyperbolic and sigmoid) are reported in the same enzyme for PPO activation by the surfactant sodium dodecyl sulfate (SDS), depending on substrate nature. A kinetic model based on cooperative systems is developed to describe the activation effect of SDS, enabling the determination of the number of surfactant molecules binding to the enzyme in the activation process.

Evidence for a common regulation in the activation of a polyphenol oxidase by trypsin and sodium dodecyl sulfate.

Polyphenol oxidase (PPO) was extracted from beet root, in both soluble and membrane fractions, and in both cases the enzyme was in a latent state. PPO from the membrane fraction showed no diphenolase activity unless it was activated by trypsin or sodium dodecyl sulfate (SDS). The kinetics of the activation process of latent PPO by trypsin was studied and the specific rate constant of active PPO formation, k 3 , showed a value of 0.

[Association between cerebral infarction and malignant glioma].

Introduction: It is very rare for cerebral infarction to be the first symptom of an intracranial tumour. Only three cases have been reported in which cerebral infarction is thought to have been caused by the arterial compromise triggered by incipient high grade gliomas that are not yet visible in radiological tests.

Case Report: A 46-year-old male with no relevant medical history or cardiovascular risk factors who presented with acute hemiplegia on the right-hand side of the body and a significantly impaired level of consciousness.

Kinetic analysis of catechin oxidation by polyphenol oxidase at neutral pH.

Catechin oxidation by peach polyphenol oxidase was performed in a pH range of 3.5-8.0.

Tyrosinase inhibitory activity of cucumber compounds: enzymes responsible for browning in cucumber.

The inhibition of mushroom tyrosinase by cucumber extracts was evaluated. The inhibitory effect was measured by both polarographic and spectrophotometric methods. The commercial aldehyde, trans,cis-2,6-nonadienal, described as a major volatile compound of cucumber, was characterized as a noncompetitive inhibitor against 4-tert-butylcatechol oxidation by mushroom tyrosinase.

Determination of the phospholipase activity of patatin by a continuous spectrophotometric assay.

Patatin is a family of glycoproteins that accounts for 30-40% of the total soluble protein in potato (Solanum tuberosum L.) tubers. This protein has been reported to serve as a storage protein and also to exhibit lipid phospholipase activity.

A continuous spectrophotometric assay for phospholipase A(2) activity.

This paper describes a simple continuous spectrophotometric method for assaying phospholipase A(2) (PLA(2)) activity. The procedure is based on a coupled enzymatic assay, using dilinoleoyl phosphatidylcholine as phospholipase substrate and lipoxygenase as coupling enzyme. The linoleic acid released by phospholipase was oxidized by lipoxygenase and then phospholipase activity was followed spectrophotometrically by measuring the increase in absorbance at 234 nm due to the formation of the corresponding hydroperoxide from the linoleic acid.

Molecular characterization of ochratoxin A producing strains of the genus Penicillium.

Sixty-six strains classified as P. verrucosum based on morphological criteria were characterized by molecular methods like RAPD, AFLP and ITS sequencing. Two groups could be identified by RAPD and AFLP analyses.

Characterization of patatin esterase activity in AOT-isooctane reverse micelles.

Patatin is a family of glycoproteins that accounts for 30-40% of the total soluble protein in potato (Solanum tuberosum L.) tubers. This protein has been reported not only to serve as a storage protein but also to exhibit lipid acyl hydrolase (LAH) activity.