TY - CONF AU - Kozma-Bognárné Hamari, Zsuzsanna AU - Eszter, Bokor AU - Ámon, Judit AU - Varga, Mónika AU - Szekeres, András AU - Hegedüs, Zsófia AU - Tamás, Jakusch AU - Szakonyi, Zsolt AU - Flipphi, Michel Johannes Anthonie AU - Vágvölgyi, Csaba AU - Gácser, Attila AU - Claudio, Scazzocchio TI - NICOTINIC ACID CATABOLISM IN ASPERGILLUS NIDULANS: AN EXAMPLE OF CONVERGENT EVOLUTION T2 - 16th European Conference on Fungal Genetics: Programme & Abstracts PB - Universität Innsbruck C1 - Innsbruck PY - 2023 SP - 767 EP - 768 PG - 2 UR - https://m2.mtmt.hu/api/publication/33693549 ID - 33693549 AB - Nicotinic acid (niacin) is a precursor of NAD and NADP and thus an essential metabolite. Its degradation has been previously described only in bacteria. We describe, for the first time, a complete eukaryotic pathway of nico- tinic acid (NA) catabolism. The genes are organised in three co-regu- lated gene clusters, which encode eight enzymes, two transporters and the pathway specific transcription factor. The pathway is conserved; and its variable organisation in the Pezizomycotina illustrates cluster evolution and horizontal gene transfer. Reverse genetics was coupled with state-of-the-art chemical charac- terisation of each intermediate. The first step, the conversion of NA to 6-hydroxynicotinic acid (6-NA) is common to prokaryotic and eukary- otic pathways, even if catalysed by independently evolved enzymes. While two downstream metabolites, 2,5-dihydroxypyridine and 2,3,6-tri- hydroxypyridine, are common to various prokaryotic routes, other steps and metabolites are unprecedented: 3-hydroxypiperidine-2,6-dione and 5,6-dihydroxypiperidine-2-one intermediate metabolites have not been identified previously in any organism, the latter being a completely nov- el chemical compound. Furthermore, the hydrolytic N-C ring opening results in α-hydroxyglutaramate, a compound not detected in analo- gous prokaryotic pathways. Remarkably, the physiological inducer of the whole pathway is a near-terminal intermediate metabolite: 5,6-di- hydroxypiperidine-2-one. While most steps are cytosolic, two steps take place in the peroxi- somes. 6-NA monooxygenase (HxnX) enters peroxisomes through a canonical PTS-1 signal, while HxnW, a polyol dehydrogenase, is co-transported by piggybacking HxnX. The genomic organisation and phylogeny of the pathway cognate genes and proteins, showed that this catabolic pathway is of fungal (Ascomycota) origin and thus it exemplifies convergent evolution of catabolic pathways between fungi and bacteria, where at least four different pathways occur. LA - English DB - MTMT ER - TY - JOUR AU - Ámon, Judit AU - Varga, Gabriella Imola AU - Pfeiffer, Ilona AU - Farkas, Zoltán AU - Karácsony, Zoltán AU - Hegedüs, Zsófia AU - Vágvölgyi, Csaba AU - Kozma-Bognárné Hamari, Zsuzsanna TI - The role of the Aspergillus nidulans high mobility group B protein HmbA, the orthologue of Saccharomyces cerevisiae Nhp6p JF - SCIENTIFIC REPORTS J2 - SCI REP VL - 12 PY - 2022 IS - 1 PG - 15 SN - 2045-2322 DO - 10.1038/s41598-022-22202-3 UR - https://m2.mtmt.hu/api/publication/33188394 ID - 33188394 N1 - Department of Microbiology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary Synthetic and Systems Biology Unit, Institute of Biochemistry, Biological Research Centre, Eötvös Loránd Research Network, Szeged, Hungary Food and Wine Research Institute, Eszterházy Károly University, Eger, Hungary Export Date: 26 January 2023 Correspondence Address: Hamari, Z.; Department of Microbiology, Hungary; email: hamari@bio.u-szeged.hu Chemicals/CAS: carbon, 7440-44-0; chitinase, 9001-06-3; high mobility group B protein, 431548-19-5; nitrogen, 7727-37-9; sterigmatocystin, 10048-13-2; Carbon; Chitinases; Chromatin; Fungal Proteins; HMGB Proteins; HMGB1 Protein; Nitrogen; Saccharomyces cerevisiae Proteins; Sterigmatocystin AB - The mammalian HMGB1 is a high-mobility-group B protein, which is both an architectural and functional element of chromatin. Nhp6p, the extensively studied fungal homologue of HMGB1 in Saccharomyces cerevisiae has pleiotropic physiological functions. Despite the existence of Nhp6p orthologues in filamentous ascomycetes, little is known about their physiological roles besides their contribution to sexual development. Here we study the function of HmbA, the Aspergillus nidulans orthologue of Nhp6p. We show that HmbA influences the utilization of various carbon- and nitrogen sources, stress tolerance, secondary metabolism, hyphae elongation and maintenance of polarized growth. Additionally, by conducting heterologous expression studies, we demonstrate that HmbA and Nhp6p are partially interchangeable. HmbA restores SNR6 transcription and fitness of nhp6AΔBΔ mutant and reverses its heat sensitivity. Nhp6Ap complements several phenotypes of hmbAΔ , including ascospore formation, utilization of various carbon- and nitrogen-sources, radial growth rate, hypha elongation by polarized growth. However, Nhp6Ap does not complement sterigmatocystin production in a hmbAΔ strain. Finally, we also show that HmbA is necessary for the normal expression of the endochitinase chiA , a cell wall re-modeller that is pivotal for the normal mode of maintenance of polar growth. LA - English DB - MTMT ER - TY - JOUR AU - Bokor, Eszter AU - Ámon, Judit AU - Varga, Mónika AU - Szekeres, András AU - Hegedüs, Zsófia AU - Jakusch, Tamás AU - Szakonyi, Zsolt AU - Flipphi, Michel Johannes Anthonie AU - Vágvölgyi, Csaba AU - Gácser, Attila AU - Scazzocchio, Claudio AU - Kozma-Bognárné Hamari, Zsuzsanna TI - A complete nicotinate degradation pathway in the microbial eukaryote Aspergillus nidulans JF - COMMUNICATIONS BIOLOGY J2 - COMMUN BIOL VL - 5 PY - 2022 IS - 1 PG - 11 SN - 2399-3642 DO - 10.1038/s42003-022-03684-3 UR - https://m2.mtmt.hu/api/publication/33025855 ID - 33025855 N1 - University of Szeged Faculty of Science and Informatics, Department of Microbiology, Szeged, Hungary University of Szeged Faculty of Science and Informatics, Department of Inorganic and Analytical Chemistry, Szeged, Hungary University of Szeged Faculty of Pharmacy, Institute of Pharmaceutical Chemistry, Szeged, Hungary Institute de Génétique et Microbiologie, Université Paris-Sud, Orsay, France HCEMM-USZ Fungal Pathogens Research Group, University of Szeged Faculty of Science and Informatics, Department of Microbiology, Szeged, Hungary MTA-SZTE “Lendület” Mycobiome Research Group, University of Szeged, Szeged, Hungary Section of Microbiology, Department of Infectious Diseases, Imperial College, London, United Kingdom Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, 91198, France Department of Biochemical Engineering, Faculty of Science and Technology, University of Debrecen, Debrecen, Hungary Export Date: 27 July 2023 Correspondence Address: Hamari, Z.; University of Szeged Faculty of Science and Informatics, Hungary; email: hamari@bio.u-szeged.hu Correspondence Address: Scazzocchio, C.; Section of Microbiology, United Kingdom; email: c.scazzocchio@imperial.ac.uk Chemicals/CAS: nicotinic acid, 54-86-4, 59-67-6; Niacin; Transcription Factors AB - Several strikingly different aerobic and anaerobic pathways of nicotinate breakdown are extant in bacteria. Here, through reverse genetics and analytical techniques we elucidated in Aspergillus nidulans, a complete eukaryotic nicotinate utilization pathway. The pathway extant in this fungus and other ascomycetes, is quite different from bacterial ones. All intermediate metabolites were identified. The cognate proteins, encoded by eleven genes (hxn) mapping in three clusters are co-regulated by a specific transcription factor. Several enzymatic steps have no prokaryotic equivalent and two metabolites, 3-hydroxypiperidine-2,6-dione and 5,6-dihydroxypiperidine-2-one, have not been identified previously in any organism, the latter being a novel chemical compound. Hydrolytic ring opening results in α-hydroxyglutaramate, a compound not detected in analogous prokaryotic pathways. Our earlier phylogenetic analysis of Hxn proteins together with this complete biochemical pathway illustrates convergent evolution of catabolic pathways between fungi and bacteria. LA - English DB - MTMT ER - TY - JOUR AU - Kozma-Bognárné Hamari, Zsuzsanna AU - Bokor, Eszter AU - Ámon, Judit AU - Hegedüs, Zsófia AU - Varga, Mónika AU - Szekeres, András AU - Jakusch, Tamás AU - Vágvölgyi, Csaba TI - Nicotinate degradation in a microbial eukaryote: a novel, complete pathway extant in Aspergillus nidulans JF - ACTA MICROBIOLOGICA ET IMMUNOLOGICA HUNGARICA J2 - ACTA MICROBIOL IMMUNOL HUNG VL - 68 PY - 2021 IS - Supplement 1 SP - 69 EP - 70 PG - 2 SN - 1217-8950 UR - https://m2.mtmt.hu/api/publication/32469677 ID - 32469677 LA - English DB - MTMT ER - TY - JOUR AU - Ámon, Judit AU - Bokor, Eszter AU - Vágvölgyi, Csaba AU - Kozma-Bognárné Hamari, Zsuzsanna TI - In vitro study of the neofunctionalization of the nicotinate hydroxylase HxnS, a paralogue of the xanthine dehydrogenase HxA JF - ACTA MICROBIOLOGICA ET IMMUNOLOGICA HUNGARICA J2 - ACTA MICROBIOL IMMUNOL HUNG VL - 68 PY - 2021 IS - Supplement 1 SP - 55 EP - 56 PG - 2 SN - 1217-8950 UR - https://m2.mtmt.hu/api/publication/32469634 ID - 32469634 LA - English DB - MTMT ER - TY - JOUR AU - Ámon, Judit AU - Bokor, Eszter AU - Varga, Gabriella Imola AU - Vágvölgyi, Csaba AU - Kozma-Bognárné Hamari, Zsuzsanna TI - Aberrant chitin deposition of HmbA HMGB protein deficient Aspergillus nidulans JF - ACTA MICROBIOLOGICA ET IMMUNOLOGICA HUNGARICA J2 - ACTA MICROBIOL IMMUNOL HUNG VL - 68 PY - 2021 IS - Supplement 1 SP - 5 EP - 5 PG - 1 SN - 1217-8950 UR - https://m2.mtmt.hu/api/publication/32469613 ID - 32469613 LA - English DB - MTMT ER - TY - JOUR AU - Bokor, Eszter AU - Flipphi, Michel Johannes Anthonie AU - Kocsubé, Sándor AU - Ámon, Judit AU - Vágvölgyi, Csaba AU - Scazzocchio, Claudio AU - Kozma-Bognárné Hamari, Zsuzsanna TI - Genome organization and evolution of a eukaryotic nicotinate co-inducible pathway JF - OPEN BIOLOGY J2 - OPEN BIOL VL - 11 PY - 2021 IS - 9 PG - 14 SN - 2046-2441 DO - 10.1098/rsob.210099 UR - https://m2.mtmt.hu/api/publication/32258405 ID - 32258405 AB - In Aspergillus nidulans a regulon including 11 hxn genes (hxnS, T, R, P, Y, Z, X, W, V, M and N) is inducible by a nicotinate metabolic derivative, repressible by ammonium and under stringent control of the nitrogen-state-sensitive GATA factor AreA and the specific transcription factor HxnR. This is the first report in a eukaryote of the genomic organization of a possibly complete pathway of nicotinate utilization. In A. nidulans the regulon is organized in three distinct clusters, this organization is variable in the Ascomycota. In some Pezizomycotina species all 11 genes map in a single cluster; in others they map in two clusters. This variable organization sheds light on cluster evolution. Instances of gene duplication followed by or simultaneous with integration in the cluster, partial or total cluster loss, and horizontal gene transfer of several genes (including an example of whole cluster re-acquisition in Aspergillus of section Flavi) were detected, together with the incorporation in some clusters of genes not found in the A. nidulans co-regulated regulon, which underlie both the plasticity and the reticulate character of metabolic cluster evolution. This study provides a comprehensive phylogeny of six members of the cluster across representatives of all Ascomycota classes. LA - English DB - MTMT ER - TY - CONF AU - Bokor, Eszter AU - Ámon, Judit AU - Varga, Mónika AU - Szekeres, András AU - Claudio, Scazzocchio AU - Vágvölgyi, Csaba AU - Kozma-Bognárné Hamari, Zsuzsanna TI - The nicotinic acid pathway of Aspergillus nidulans includes a reversible conversion to 6-hydroxynicotinic acid T2 - 15th European Conference on Fungal Genetics (ECFG15): Program and Abstracts PY - 2020 SP - 235 EP - 235 PG - 1 UR - https://m2.mtmt.hu/api/publication/31354492 ID - 31354492 LA - English DB - MTMT ER - TY - CONF AU - Bokor, Eszter AU - Ámon, Judit AU - Claudio, Scazzocchio AU - Vágvölgyi, Csaba AU - Kozma-Bognárné Hamari, Zsuzsanna TI - Structural homology function predictions for fungal nicotinate catabolising enzymes T2 - 15th European Conference on Fungal Genetics (ECFG15): Program and Abstracts PY - 2020 SP - 236 EP - 236 PG - 236 UR - https://m2.mtmt.hu/api/publication/31354491 ID - 31354491 LA - English DB - MTMT ER - TY - CONF AU - Ámon, Judit AU - Bokor, Eszter AU - Vágvölgyi, Csaba AU - Claudio, Scazzocchio AU - Kozma-Bognárné Hamari, Zsuzsanna TI - In vitro enzyme evolution of Purine Hydroxylase I (HxA) and Purine Hydroxylase II (HxnS) T2 - 15th European Conference on Fungal Genetics (ECFG15): Program and Abstracts PY - 2020 SP - 235 EP - 236 PG - 2 UR - https://m2.mtmt.hu/api/publication/31354464 ID - 31354464 LA - English DB - MTMT ER -