Johannes A Mayr

Summary

Affiliation: Paracelsus Private Medical University
Country: Austria

Publications

  1. Zimmermann F, Neureiter D, Sperl W, Mayr J, Kofler B. Alterations of Oxidative Phosphorylation Complexes in Papillary Thyroid Carcinoma. Cells. 2018;7: pubmed publisher
  2. Mayr J, Feichtinger R, Tort F, Ribes A, Sperl W. Lipoic acid biosynthesis defects. J Inherit Metab Dis. 2014;37:553-63 pubmed publisher
    ..As in DLD deficiency, a broader clinical spectrum can be anticipated for lipoate synthesis defects depending on which of the affected enzymes is most rate limiting. ..
  3. Zimmermann F, Neureiter D, Feichtinger R, Trost A, Sperl W, Kofler B, et al. Deficiency of respiratory chain complex I in Hashimoto thyroiditis. Mitochondrion. 2016;26:1-6 pubmed publisher
    ..In addition to isolated complex I deficiency, 25% of oncocytic lesions showed combined deficiency of complex I and IV. Thus, we demonstrate for the first time a defect of respiratory chain complex I in OCs of HT patients. ..
  4. Mayr J, Zimmermann F, Horvath R, Schneider H, Schoser B, Holinski Feder E, et al. Deficiency of the mitochondrial phosphate carrier presenting as myopathy and cardiomyopathy in a family with three affected children. Neuromuscul Disord. 2011;21:803-8 pubmed publisher
    ..We identified a homozygous mutation c.158-9A>G located in the 5'-intron next to exon 3A specific for heart and skeletal muscle. This creates a novel splice site resulting in a more than 95% decrease of the wild type allele. ..
  5. Mayr J, Haack T, Freisinger P, Karall D, Makowski C, Koch J, et al. Spectrum of combined respiratory chain defects. J Inherit Metab Dis. 2015;38:629-40 pubmed publisher
    ..They can present as classical encephalomyopathy but also with hepatopathy, nephropathy, haematologic findings and Perrault syndrome in a subset of disorders. ..
  6. Piekutowska Abramczuk D, Assouline Z, Mataković L, Feichtinger R, Koňaříková E, Jurkiewicz E, et al. NDUFB8 Mutations Cause Mitochondrial Complex I Deficiency in Individuals with Leigh-like Encephalomyopathy. Am J Hum Genet. 2018;102:460-467 pubmed publisher
    ..Hereby we establish NDUFB8 as a relevant gene in childhood-onset mitochondrial disease. ..
  7. Feichtinger R, Zimmermann F, Mayr J, Neureiter D, Hauser Kronberger C, Schilling F, et al. Low aerobic mitochondrial energy metabolism in poorly- or undifferentiated neuroblastoma. BMC Cancer. 2010;10:149 pubmed publisher
  8. Mayr J, Zimmermann F, Fauth C, Bergheim C, Meierhofer D, Radmayr D, et al. Lipoic acid synthetase deficiency causes neonatal-onset epilepsy, defective mitochondrial energy metabolism, and glycine elevation. Am J Hum Genet. 2011;89:792-7 pubmed publisher
    ..Investigation of the mitochondrial energy metabolism showed reduced oxidation of pyruvate and decreased pyruvate dehydrogenase complex activity. A pronounced reduction of the prosthetic group lipoamide was found in lipoylated proteins. ..
  9. Mayr J, Freisinger P, Schlachter K, Rolinski B, Zimmermann F, Scheffner T, et al. Thiamine pyrophosphokinase deficiency in encephalopathic children with defects in the pyruvate oxidation pathway. Am J Hum Genet. 2011;89:806-12 pubmed publisher
    ..A reduced concentration of TPP was found in the muscle and blood. Mutation analysis of TPK1 uncovered three missense, one splice-site, and one frameshift mutation resulting in decreased TPK protein levels. ..

More Information

Publications14

  1. Mayr J, Merkel O, Kohlwein S, Gebhardt B, Böhles H, Fötschl U, et al. Mitochondrial phosphate-carrier deficiency: a novel disorder of oxidative phosphorylation. Am J Hum Genet. 2007;80:478-84 pubmed
    ..The enzyme defect was confirmed by complementation analysis in yeast. This is the first report of patients with mitochondrial phosphate-carrier deficiency. ..
  2. Mayr J, Bodamer O, Haack T, Zimmermann F, Madignier F, Prokisch H, et al. Heterozygous mutation in the X chromosomal NDUFA1 gene in a girl with complex I deficiency. Mol Genet Metab. 2011;103:358-61 pubmed publisher
    ..Investigation of the X-inactivation pattern demonstrated that 74% of the paternally inherited allele was active in the muscle. This is the first report of an X-chromosomally inherited respiratory chain defect in a heterozygous female. ..
  3. Koch J, Freisinger P, Feichtinger R, Zimmermann F, Rauscher C, Wagentristl H, et al. Mutations in TTC19: expanding the molecular, clinical and biochemical phenotype. Orphanet J Rare Dis. 2015;10:40 pubmed publisher
    ..However, TTC19 deficient patients do show characteristic clinical and neuroimaging features, which may facilitate diagnosis of this yet rare disorder. Normal MRC complex III activity does not exclude the diagnosis. ..
  4. Kennedy H, Haack T, Hartill V, Mataković L, Baumgartner E, Potter H, et al. Sudden Cardiac Death Due to Deficiency of the Mitochondrial Inorganic Pyrophosphatase PPA2. Am J Hum Genet. 2016;99:674-682 pubmed publisher
    ..These findings confirm the pathogenicity of PPA2 mutations and suggest that PPA2 is a cardiomyopathy-associated protein, which has a greater physiological importance in mitochondrial function than previously recognized. ..
  5. Habarou F, Hamel Y, Haack T, Feichtinger R, Lebigot E, Marquardt I, et al. Biallelic Mutations in LIPT2 Cause a Mitochondrial Lipoylation Defect Associated with Severe Neonatal Encephalopathy. Am J Hum Genet. 2017;101:283-290 pubmed publisher
    ..Lipoic acid supplementation did not improve clinical condition nor activities of PDHc, ?-KGDHc, or leucine metabolism in fibroblasts and was ineffective in yeast deleted for the orthologous LIP2. ..