PURPOSE: Zellweger spectrum disorders (ZSDs) are known as autosomal recessive disorders caused by defective peroxisome biogenesis due to bi-allelic pathogenic variants in any of at least 13 different PEX genes. Here, we report 2 unrelated patients who present with an autosomal dominant ZSD. METHODS: We performed biochemical and genetic studies in blood and skin fibroblasts of the patients and demonstrated the pathogenicity of the identified PEX14 variants by functional cell studies. RESULTS: We identified 2 different single heterozygous de novo variants in the PEX14 genes of 2 patients diagnosed with ZSD. Both variants cause messenger RNA mis-splicing, leading to stable expression of similar C-terminally truncated PEX14 proteins. Functional studies indicated that the truncated PEX14 proteins lost their function in peroxisomal matrix protein import and cause increased degradation of peroxisomes, ie, pexophagy, thus exerting a dominant-negative effect on peroxisome functioning. Inhibition of pexophagy by different autophagy inhibitors or genetic knockdown of the peroxisomal autophagy receptor NBR1 resulted in restoration of peroxisomal functions in the patients' fibroblasts. CONCLUSION: Our finding of an autosomal dominant ZSD expands the genetic repertoire of ZSDs. Our study underscores that single heterozygous variants should not be ignored as possible genetic cause of diseases with an established autosomal recessive mode of inheritance.

• MeSH
• alely MeSH
• lidé MeSH
• peroxizomy genetika   metabolismus   MeSH
• proteiny genetika   MeSH
• transport proteinů fyziologie   MeSH
• Zellwegerův syndrom * genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

BACKGROUND: Mitochondria and peroxisomes are the two organelles that are most affected during adaptation to microoxic or anoxic environments. Mitochondria are known to transform into anaerobic mitochondria, hydrogenosomes, mitosomes, and various transition stages in between, collectively called mitochondrion-related organelles (MROs), which vary in enzymatic capacity. Anaerobic peroxisomes were identified only recently, and their putatively most conserved function seems to be the metabolism of inositol. The group Archamoebae includes anaerobes bearing both anaerobic peroxisomes and MROs, specifically hydrogenosomes in free-living Mastigamoeba balamuthi and mitosomes in the human pathogen Entamoeba histolytica, while the organelles within the third lineage represented by Pelomyxa remain uncharacterized. RESULTS: We generated high-quality genome and transcriptome drafts from Pelomyxa schiedti using single-cell omics. These data provided clear evidence for anaerobic derivates of mitochondria and peroxisomes in this species, and corresponding vesicles were tentatively identified in electron micrographs. In silico reconstructed MRO metabolism harbors respiratory complex II, electron-transferring flavoprotein, a partial TCA cycle running presumably in the reductive direction, pyruvate:ferredoxin oxidoreductase, [FeFe]-hydrogenases, a glycine cleavage system, a sulfate activation pathway, and an expanded set of NIF enzymes for iron-sulfur cluster assembly. When expressed in the heterologous system of yeast, some of these candidates localized into mitochondria, supporting their involvement in the MRO metabolism. The putative functions of P. schiedti peroxisomes could be pyridoxal 5'-phosphate biosynthesis, amino acid and carbohydrate metabolism, and hydrolase activities. Unexpectedly, out of 67 predicted peroxisomal enzymes, only four were also reported in M. balamuthi, namely peroxisomal processing peptidase, nudix hydrolase, inositol 2-dehydrogenase, and D-lactate dehydrogenase. Localizations in yeast corroborated peroxisomal functions of the latter two. CONCLUSIONS: This study revealed the presence and partially annotated the function of anaerobic derivates of mitochondria and peroxisomes in P. schiedti using single-cell genomics, localizations in yeast heterologous systems, and transmission electron microscopy. The MRO metabolism resembles that of M. balamuthi and most likely reflects the state in the common ancestor of Archamoebae. The peroxisomal metabolism is strikingly richer in P. schiedti. The presence of myo-inositol 2-dehydrogenase in the predicted peroxisomal proteome corroborates the situation in other Archamoebae, but future experimental evidence is needed to verify additional functions of this organelle.

• MeSH
• Amoeba * genetika   metabolismus   MeSH
• anaerobióza MeSH
• Archamoebae * genetika   metabolismus   MeSH
• genomika MeSH
• lidé MeSH
• mitochondrie metabolismus   MeSH
• peroxizomy metabolismus   MeSH
• Saccharomyces cerevisiae MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Baker's yeast is a valuable model system for the study of biological aging as it can be utilized for the measurement of replicative and chronological life spans in response to interventions. Whereas replicative aging in Saccharomyces cerevisiae mirrors dividing mammalian cells, chronological aging is seen in non-dividing cells. Aging is strongly influenced by the cellular organelles, especially by mitochondria which house essential functions like oxidative phosphorylation. Additionally, peroxisomes were shown to modulate the aging process, mainly by their turnover of reactive oxygen species. There is a fundamental interest in understanding how mitochondria and peroxisomes contribute to cellular aging. This work analyzes chronological aging in yeast mutants that are affected in peroxisomal proliferation and inheritance. Deletion of INP1 (retention of peroxisomes in the mother cell) or PEX11 (division of peroxisomes) leads to clearly reduced life spans compared to the wild-type control under conditions which depend on peroxisomal metabolism. Δinp1 cells are long-lived in contrast to the wild type and Δpex11 when assayed under conditions that not necessitate peroxisome function. Neither treatment affects the index of respiratory capacity, indicating fully functional mitochondria. Evaluation of stress resistances reveals that Δinp1 has significantly higher resistance to the apoptosis elicitor acetic acid. Old Δpex11 cells from an oleate culture are more susceptible to hydrogen peroxide treatment compared to Δinp1 and the wild type. Finally, aged cells are hyper-sensitive to heat shock treatment in contrast to young cells.

• MeSH
• delece genu MeSH
• membránové proteiny genetika   metabolismus   MeSH
• mikrobiální viabilita MeSH
• peroxiny genetika   metabolismus   MeSH
• peroxizomy genetika   metabolismus   MeSH
• proliferace buněk MeSH
• reaktivní formy kyslíku metabolismus   MeSH
• Saccharomyces cerevisiae - proteiny genetika   metabolismus   MeSH
• Saccharomyces cerevisiae genetika   růst a vývoj   metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH

Introduced about a century ago, suramin remains a frontline drug for the management of early-stage East African trypanosomiasis (sleeping sickness). Cellular entry into the causative agent, the protozoan parasite Trypanosoma brucei, occurs through receptor-mediated endocytosis involving the parasite's invariant surface glycoprotein 75 (ISG75), followed by transport into the cytosol via a lysosomal transporter. The molecular basis of the trypanocidal activity of suramin remains unclear, but some evidence suggests broad, but specific, impacts on trypanosome metabolism (i.e. polypharmacology). Here we observed that suramin is rapidly accumulated in trypanosome cells proportionally to ISG75 abundance. Although we found little evidence that suramin disrupts glycolytic or glycosomal pathways, we noted increased mitochondrial ATP production, but a net decrease in cellular ATP levels. Metabolomics highlighted additional impacts on mitochondrial metabolism, including partial Krebs' cycle activation and significant accumulation of pyruvate, corroborated by increased expression of mitochondrial enzymes and transporters. Significantly, the vast majority of suramin-induced proteins were normally more abundant in the insect forms compared with the blood stage of the parasite, including several proteins associated with differentiation. We conclude that suramin has multiple and complex effects on trypanosomes, but unexpectedly partially activates mitochondrial ATP-generating activity. We propose that despite apparent compensatory mechanisms in drug-challenged cells, the suramin-induced collapse of cellular ATP ultimately leads to trypanosome cell death.

• MeSH
• adenosintrifosfát metabolismus   MeSH
• energetický metabolismus účinky léků   MeSH
• flagella účinky léků   metabolismus   ultrastruktura   MeSH
• glykolýza účinky léků   MeSH
• kyselina pyrohroznová metabolismus   MeSH
• membránový potenciál mitochondrií účinky léků   MeSH
• metabolom účinky léků   MeSH
• mikrotělíska účinky léků   metabolismus   ultrastruktura   MeSH
• mitochondrie účinky léků   metabolismus   ultrastruktura   MeSH
• molekulární modely MeSH
• prolin metabolismus   MeSH
• proteom metabolismus   MeSH
• protonové ATPasy metabolismus   MeSH
• protozoální proteiny metabolismus   MeSH
• suramin farmakologie   MeSH
• Trypanosoma brucei brucei metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The adaptation of eukaryotic cells to anaerobic conditions is reflected by substantial changes to mitochondrial metabolism and functional reduction. Hydrogenosomes belong among the most modified mitochondrial derivative and generate molecular hydrogen concomitant with ATP synthesis. The reduction of mitochondria is frequently associated with loss of peroxisomes, which compartmentalize pathways that generate reactive oxygen species (ROS) and thus protect against cellular damage. The biogenesis and function of peroxisomes are tightly coupled with mitochondria. These organelles share fission machinery components, oxidative metabolism pathways, ROS scavenging activities, and some metabolites. The loss of peroxisomes in eukaryotes with reduced mitochondria is thus not unexpected. Surprisingly, we identified peroxisomes in the anaerobic, hydrogenosome-bearing protist Mastigamoeba balamuthi We found a conserved set of peroxin (Pex) proteins that are required for protein import, peroxisomal growth, and division. Key membrane-associated Pexs (MbPex3, MbPex11, and MbPex14) were visualized in numerous vesicles distinct from hydrogenosomes, the endoplasmic reticulum (ER), and Golgi complex. Proteomic analysis of cellular fractions and prediction of peroxisomal targeting signals (PTS1/PTS2) identified 51 putative peroxisomal matrix proteins. Expression of selected proteins in Saccharomyces cerevisiae revealed specific targeting to peroxisomes. The matrix proteins identified included components of acyl-CoA and carbohydrate metabolism and pyrimidine and CoA biosynthesis, whereas no components related to either β-oxidation or catalase were present. In conclusion, we identified a subclass of peroxisomes, named "anaerobic" peroxisomes that shift the current paradigm and turn attention to the reductive evolution of peroxisomes in anaerobic organisms.

• MeSH
• anaerobióza MeSH
• Archamoebae genetika   metabolismus   MeSH
• mitochondrie genetika   metabolismus   MeSH
• oxidace-redukce MeSH
• peroxiny genetika   metabolismus   MeSH
• peroxizomy genetika   metabolismus   MeSH
• protozoální proteiny genetika   metabolismus   MeSH
• reaktivní formy kyslíku metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

INTRODUCTION: Currently, no therapies are available for Zellweger spectrum disorders (ZSDs), a group of genetic metabolic disorders characterised by a deficiency of functional peroxisomes. In a previous study, we showed that oral cholic acid (CA) treatment can suppress bile acid synthesis in ZSD patients and, thereby, decrease plasma levels of toxic C27 -bile acid intermediates, one of the biochemical abnormalities in these patients. However, no effect on clinically relevant outcome measures could be observed after 9 months of CA treatment. It was noted that, in patients with advanced liver disease, caution is needed because of possible hepatotoxicity. METHODS: An extension study of the previously conducted pretest-posttest design study was conducted including 17 patients with a ZSD. All patients received oral CA for an additional period of 12 months, encompassing a total of 21 months of treatment. Multiple clinically relevant parameters and markers for bile acid synthesis were assessed after 15 and 21 months of treatment. RESULTS: Bile acid synthesis was still suppressed after 21 months of CA treatment, accompanied with reduced levels of C27 -bile acid intermediates in plasma. These levels significantly increased again after discontinuation of CA. No significant changes were found in liver tests, liver elasticity, coagulation parameters, fat-soluble vitamin levels or body weight. CONCLUSIONS: Although CA treatment did lead to reduced levels of toxic C27 -bile acid intermediates in ZSD patients without severe liver fibrosis or cirrhosis, no improvement of clinically relevant parameters was observed after 21 months of treatment. We discuss the implications for CA therapy in ZSD based on these results.

• MeSH
• aplikace orální MeSH
• biologické markery krev   MeSH
• dítě MeSH
• dospělí MeSH
• játra metabolismus   MeSH
• kyselina cholová krev   terapeutické užití   MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• nemoci jater farmakoterapie   metabolismus   MeSH
• peroxizomy metabolismus   MeSH
• předškolní dítě MeSH
• Zellwegerův syndrom krev   farmakoterapie   metabolismus   MeSH
• žlučové kyseliny a soli metabolismus   MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

: Jasmonic acid (JA) and its related derivatives are ubiquitously occurring compounds of land plants acting in numerous stress responses and development. Recent studies on evolution of JA and other oxylipins indicated conserved biosynthesis. JA formation is initiated by oxygenation of α-linolenic acid (α-LeA, 18:3) or 16:3 fatty acid of chloroplast membranes leading to 12-oxo-phytodienoic acid (OPDA) as intermediate compound, but in Marchantiapolymorpha and Physcomitrellapatens, OPDA and some of its derivatives are final products active in a conserved signaling pathway. JA formation and its metabolic conversion take place in chloroplasts, peroxisomes and cytosol, respectively. Metabolites of JA are formed in 12 different pathways leading to active, inactive and partially active compounds. The isoleucine conjugate of JA (JA-Ile) is the ligand of the receptor component COI1 in vascular plants, whereas in the bryophyte M. polymorpha COI1 perceives an OPDA derivative indicating its functionally conserved activity. JA-induced gene expressions in the numerous biotic and abiotic stress responses and development are initiated in a well-studied complex regulation by homeostasis of transcription factors functioning as repressors and activators.

• MeSH
• chloroplasty metabolismus   MeSH
• cyklopentany metabolismus   MeSH
• druhová specificita MeSH
• kyselina alfa-linolenová metabolismus   MeSH
• Marchantia metabolismus   MeSH
• mastné kyseliny metabolismus   MeSH
• mechy metabolismus   MeSH
• metabolické sítě a dráhy MeSH
• nenasycené mastné kyseliny metabolismus   MeSH
• oxylipiny metabolismus   MeSH
• peroxizomy metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

The transport of peroxisomal membrane proteins (PMPs) requires the soluble PEX19 protein as chaperone and import receptor. Recognition of cargo PMPs by the C-terminal domain (CTD) of PEX19 is required for peroxisome biogenesis in vivo. Farnesylation at a C-terminal CaaX motif in PEX19 enhances the PMP interaction, but the underlying molecular mechanisms are unknown. Here, we report the NMR-derived structure of the farnesylated human PEX19 CTD, which reveals that the farnesyl moiety is buried in an internal hydrophobic cavity. This induces substantial conformational changes that allosterically reshape the PEX19 surface to form two hydrophobic pockets for the recognition of conserved aromatic/aliphatic side chains in PMPs. Mutations of PEX19 residues that either mediate farnesyl contacts or are directly involved in PMP recognition abolish cargo binding and cannot complement a ΔPEX19 phenotype in human Zellweger patient fibroblasts. Our results demonstrate an allosteric mechanism for the modulation of protein function by farnesylation.

• MeSH
• alkyltransferasy a aryltransferasy chemie   genetika   metabolismus   MeSH
• alosterická regulace MeSH
• exprese genu MeSH
• fibroblasty metabolismus   patologie   MeSH
• hydrofobní a hydrofilní interakce MeSH
• interakční proteinové domény a motivy MeSH
• konformace proteinů, alfa-helix MeSH
• konformace proteinů, beta-řetězec MeSH
• lidé MeSH
• membránové proteiny chemie   genetika   metabolismus   MeSH
• mutace MeSH
• peroxizomy metabolismus   patologie   MeSH
• posttranslační úpravy proteinů * MeSH
• prenylace MeSH
• rekombinantní proteiny chemie   genetika   metabolismus   MeSH
• Saccharomyces cerevisiae - proteiny chemie   genetika   metabolismus   MeSH
• Saccharomyces cerevisiae enzymologie   genetika   MeSH
• sekvence aminokyselin MeSH
• sekvenční homologie aminokyselin MeSH
• sekvenční seřazení MeSH
• simulace molekulového dockingu MeSH
• vazba proteinů MeSH
• vazebná místa MeSH
• Zellwegerův syndrom genetika   metabolismus   patologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Nucleoside diphosphate kinases (NDPK) are key enzymes involved in the intracellular nucleotide maintenance in all living organisms, especially in trypanosomatids which are unable to synthesise purines de novo. Four putative NDPK isoforms were identified in the Trypanosoma cruzi Chagas, 1909 genome but only two of them were characterised so far. In this work, we studied a novel isoform from T. cruzi called TcNDPK3. This enzyme presents an atypical N-terminal extension similar to the DM10 domains. In T. cruzi, DM10 sequences targeted other NDPK isoform (TcNDPK2) to the cytoskeleton, but TcNDPK3 was localised in glycosomes despite lacking a typical peroxisomal targeting signal. In addition, TcNDPK3 was found only in the bloodstream trypomastigotes where glycolytic enzymes are very abundant. However, TcNDPK3 mRNA was also detected at lower levels in amastigotes suggesting regulation at protein and mRNA level. Finally, 33 TcNDPK3 gene orthologs were identified in the available kinetoplastid genomes. The characterisation of new glycosomal enzymes provides novel targets for drug development to use in therapies of trypanosomatid associated diseases.

• MeSH
• Chagasova nemoc parazitologie   MeSH
• energetický metabolismus * MeSH
• fylogeneze MeSH
• izoenzymy MeSH
• mikrotělíska enzymologie   MeSH
• nukleosiddifosfátkinasa genetika   MeSH
• proteinové domény MeSH
• protozoální proteiny genetika   MeSH
• stadia vývoje MeSH
• Trypanosoma cruzi enzymologie   genetika   fyziologie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Comparison of the genomes of free-living Bodo saltans and those of parasitic trypanosomatids reveals that the transition from a free-living to a parasitic life style has resulted in the loss of approximately 50% of protein-coding genes. Despite this dramatic reduction in genome size, B. saltans and trypanosomatids still share a significant number of common metabolic traits: glycosomes; a unique set of the pyrimidine biosynthetic pathway genes; an ATP-PFK which is homologous to the bacterial PPi -PFKs rather than to the canonical eukaryotic ATP-PFKs; an alternative oxidase; three phosphoglycerate kinases and two GAPDH isoenzymes; a pyruvate kinase regulated by fructose-2,6-bisphosphate; trypanothione as a substitute for glutathione; synthesis of fatty acids via a unique set of elongase enzymes; and a mitochondrial acetate:succinate coenzyme A transferase. B. saltans has lost the capacity to synthesize ubiquinone. Among genes that are present in B. saltans and lost in all trypanosomatids are those involved in the degradation of mureine, tryptophan and lysine. Novel acquisitions of trypanosomatids are components of pentose sugar metabolism, pteridine reductase and bromodomain-factor proteins. In addition, only the subfamily Leishmaniinae has acquired a gene for catalase and the capacity to convert diaminopimelic acid to lysine.

• MeSH
• aminokyseliny metabolismus   MeSH
• Bacteria genetika   metabolismus   MeSH
• dolichol metabolismus   MeSH
• ergosterol biosyntéza   MeSH
• Eukaryota genetika   metabolismus   MeSH
• fosfolipidy metabolismus   MeSH
• glukoneogeneze MeSH
• glykolýza MeSH
• Kinetoplastida enzymologie   genetika   metabolismus   MeSH
• koenzymy metabolismus   MeSH
• kyselina listová metabolismus   MeSH
• kyselina mevalonová metabolismus   MeSH
• metabolismus lipidů MeSH
• metabolismus sacharidů MeSH
• mikrotělíska metabolismus   MeSH
• mitochondrie enzymologie   metabolismus   MeSH
• močovina metabolismus   MeSH
• oxidoreduktasy metabolismus   MeSH
• pentózofosfátový cyklus MeSH
• peroxizomy metabolismus   MeSH
• polyaminy metabolismus   MeSH
• prenylace proteinů MeSH
• protozoální geny genetika   MeSH
• protozoální proteiny genetika   MeSH
• puriny biosyntéza   metabolismus   MeSH
• pyrimidiny biosyntéza   metabolismus   MeSH
• reaktivní formy kyslíku MeSH
• Trypanosomatina enzymologie   genetika   metabolismus   MeSH
• ubichinon metabolismus   MeSH
• vitaminy metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH