A broad distribution of the alternative oxidase in microsporidian parasites

Microsporidia are a group of obligate intracellular parasitic eukaryotes that were considered to be amitochondriate until the recent discovery of highly reduced mitochondrial organelles called mitosomes. Analysis of the complete genome of Encephalitozoon cuniculi revealed a highly reduced set of proteins in the organelle, mostly related to the assembly of ironsulphur clusters. Oxidative phosphorylation and the Krebs cycle proteins were absent, in keeping with the notion that the microsporidia and their mitosomes are anaerobic, as is the case for other mitosome bearing eukaryotes, such as Giardia. Here we provide evidence opening the possibility that mitosomes in a number of microsporidian lineages are not completely anaerobic. Specifically, we have identified and characterized a gene encoding the alternative oxidase (AOX), a typically mitochondrial terminal oxidase in eukaryotes, in the genomes of several distantly related microsporidian species, even though this gene is absent from the complete genome of E. cuniculi. In order to confirm that these genes encode functional proteins, AOX genes from both A. locustae and T. hominis were over-expressed in E. coli and AOX activity measured spectrophotometrically using ubiquinol-1 (UQ-1) as substrate. Both A. locustae and T. hominis AOX proteins reduced UQ-1 in a cyanide and antimycin-resistant manner that was sensitive to ascofuranone, a potent inhibitor of the trypanosomal AOX. The physiological role of AOX microsporidia may be to reoxidise reducing equivalents produced by glycolysis, in a manner comparable to that observed in trypanosome

„Dobra reprodukcja obrazów”. „Dzieło” Émile’a Zoli w przekładach Aleksandry Callierowej i Hanny Szumańskiej-Grossowej

The article describes a series of Polish translations of Émile Zola’s 1886 novel L’OEuvre. The translations made by Aleksandra Callierowa (1886) and by Hanna Szumańska-Grossowa (1959) were created at completely different points in history, which significantly affects both the poetics of the translations and their reception. Callierowa’s translation was contemporary to the original, it conveyed the need to quickly keep up with the fashion prevailing in literature. Szumańska-Grossowa’s work, in turn, accentuates the fact that Zola already belonged to the canon of European literature and that he deserved – in accordance with the ideological assumptions of the then communist authorities – to be read bya mass reader

Dom versus ściana. Gesty uobecnienia Stanisława Barańczaka w przestrzeni Poznania

The article discusses the presentations of Stanisław Barańczak and his poetry in Poznań’s urban space. The poet’s presentification is exemplified by the murals that have been created on the walls of buildings in Poznań after the writer’s death.The article discusses the presentations of Stanisław Barańczak and his poetry in Poznań’s urban space. The poet’s presentification is exemplified by the murals that have been created on the walls of buildings in Poznań after the writer’s death

Retoryka kulturowa jako model recepcji i interpretacji

Udostępnienie publikacji Wydawnictwa Uniwersytetu Łódzkiego finansowane w ramach projektu „Doskonałość naukowa kluczem do doskonałości kształcenia”. Projekt realizowany jest ze środków Europejskiego Funduszu Społecznego w ramach Programu Operacyjnego Wiedza Edukacja Rozwój; nr umowy: POWER.03.05.00-00-Z092/17-00

Orphan works as a challenge for humanities

The article presents the legal concept of orphan works in the context of the Polish Law on Copyright and its social and cultural impact on the effectiveness of scientific research, especially in the field of humanities. The purpose of introducing legislative solutions relating to orphan works is to save the cultural heritage from oblivion, and also to restore the continuity of scientific research. The article also raises the question of the contemporary idea of Open Access, which is considered as another plane for new humanities — as a place of common ground to exchange knowledge without barriers

Chronic Activation of AMPK Induces Mitochondrial Biogenesis through Differential Phosphorylation and Abundance of Mitochondrial Proteins in Dictyostelium discoideum

Mitochondrial biogenesis is a highly controlled process that depends on diverse signalling pathways responding to cellular and environmental signals. AMP-activated protein kinase (AMPK) is a critical metabolic enzyme that acts at a central control point in cellular energy homeostasis. Numerous studies have revealed the crucial roles of AMPK in the regulation of mitochondrial biogenesis; however, molecular mechanisms underlying this process are still largely unknown. Previously, we have shown that, in cellular slime mould Dictyostelium discoideum, the overexpression of the catalytic α subunit of AMPK led to enhanced mitochondrial biogenesis, which was accompanied by reduced cell growth and aberrant development. Here, we applied mass spectrometry-based proteomics of Dictyostelium mitochondria to determine the impact of chronically active AMPKα on the phosphorylation state and abundance of mitochondrial proteins and to identify potential protein targets leading to the biogenesis of mitochondria. Our results demonstrate that enhanced mitochondrial biogenesis is associated with variations in the phosphorylation levels and abundance of proteins related to energy metabolism, protein synthesis, transport, inner membrane biogenesis, and cellular signalling. The observed changes are accompanied by elevated mitochondrial respiratory activity in the AMPK overexpression strain. Our work is the first study reporting on the global phosphoproteome profiling of D. discoideum mitochondria and its changes as a response to constitutively active AMPK. We also propose an interplay between the AMPK and mTORC1 signalling pathways in controlling the cellular growth and biogenesis of mitochondria in Dictyostelium as a model organism