Papers by Anna Kujumdzieva
Drinking water quality management has been a key element of primary prevention and control of wat... more Drinking water quality management has been a key element of primary prevention and control of waterborne diseases for a long time. This chapter is based on the EU Project “Implementation of ECVET for Qualification Design in Drinking Water Treatment Plants and Sanitation for Pure Drinkable Water PUREH2O” that contributes to the recognition and transparency of qualifications at the EU level and provides an innovative model for competencies for the potable water sector. The main dilemma that PURE-H2O intends to tackle is the lack of mutual recognition of qualification that is often impaired by national restrictions by applying EUROPASS, European/National Qualification Framework (EQF/.NQF), and the European Credit System for Vocational Education and Training (ECVET) instruments. The aim of the project is to enhance the quality and performance of VET system improving education in drinking water supply and development. This project could also be achieved through promoting creativity, inno...
Fermentative and respiratory yeast strains of genera Saccharomyces, Kluyveromyces, Pichia, Candid... more Fermentative and respiratory yeast strains of genera Saccharomyces, Kluyveromyces, Pichia, Candida and Hansenula have been investigated for mitochondrial localization of Cu/Zn superoxide dismutase (SOD). Pure mitochondrial fractions were obtained and the specific activities of Cu/Zn and Mn SODs were measured in comparison with those in the corresponding cell-free extracts. The Cu/Zn SOD: Mn SOD ratio in mitochondria and crude extracts was calculated and was considered a specific characteristic of all tested strains. Electrophoretical visualization of SOD patterns provided evidence for possible migration of cytosolic Cu/Zn SOD to mitochondria. The characteristic Cu/Zn SOD profile in mitochondria of all tested strains suggested its ubiquity within the fermentative and respiratory yeasts.
Hansenula polymorpha CBS 4732, cultivated on media containing glucose, glycerol or methanol as ca... more Hansenula polymorpha CBS 4732, cultivated on media containing glucose, glycerol or methanol as carbon source has been investigated for specific activity of Superoxide dismutase (SOD) enzymes during batch—wise cultivation. Furthermore cell free extract from the analyzed strain cultivated on different carbon sources were subjected to 8% native PAGE. One band corresponding to sensitive of KCN Cu/Zn SOD with Rm 0.29 is inhibiting in all samples. After inhibition of cyanide sensitive Cu/Zn SOD, three bands specifically stained for SOD activity, corresponding to Mn SOD are observed in samples obtained by H. polymorpha cultivated on medium containing methanol. Two bans are retaining in glucose and glycerol grown cells. This data suggest that probably in H. polymorpha yeasts appears multiple enzyme forms of Mn SOD enzyme. Multiple enzyme forms become more stable and do not disappear after 1 min at 75°C. One band with Rm 0.34 in all yeast samples cultivated on methanol, glucose and glycerol,...
The primary structure of Cu/Zn-superoxide dismutase from Kluyveromyces marxianus NBIMCC 1984 was ... more The primary structure of Cu/Zn-superoxide dismutase from Kluyveromyces marxianus NBIMCC 1984 was elucidated by N-terminal sequence analysis of the intact protein and by determination of the amino acid sequences of tryptic peptides by MALDI–TOF–TOF tandem mass spectrometry. The molecular mass of one subunit of the homodimer SOD, containing 152 amino acid residues, was calculated to be 15858.3 Da while a value of 17096.63 Da was obtained by MALDI–TOF MS. This difference is explained by the presence of N-glycosylation of one linkage site, -Asn-Ile/Leu-Thr-, and a glycan chain with the structure Hex5 GlcNAc2. Glycosylation of K. marxianus superoxide dismutase is a post-translational modification. Recent developments in mass spectrometry have enabled detailed structural analyses of covalent modifications of proteins. Therefore, in this paper, we introduce a covalent modification of Cu/Zn-SOD from K. marxianus NBIMCC 1984, by analysis of the enzymatic liberated N-glycan from the enzyme us...
Educational Programs based on Information and Communication Technologies (ICT) contribute to the ... more Educational Programs based on Information and Communication Technologies (ICT) contribute to the quality of education and training and to Europe’s move to a knowledge based society. The European Commission has been very active in supporting and complementing the efforts of EU Member States in this fi eld. The Leonardo da Vinci Program is a part from the efforts implementing the e-learning Initiative and Action Plan in operation through different measures (pilot projects, transnational networks, etc.). This way it has gained considerable experience in encouraging cooperation, networking and exchange of good practices at European level. Introduction of e-learning approach is a further step towards realization the vision of technology serving lifelong learning. It focuses on a set of actions in high priority area, such as Biotechnology and Public Health, chosen for their strategic relevance to the modernization of Europe’s education and training system. The infi ltration of new communi...
Summary Monascus sp. 94-25 strain was isolated from red rice with the purpose of red pigments sub... more Summary Monascus sp. 94-25 strain was isolated from red rice with the purpose of red pigments submerged production. Morphological characterisation on the taxonomically important for the genus media, showed that the strain produced cleistothecia with oval ascospores and aleiroconidia. Comparison with a referent strain Monascus purpureus Went 109.07 was made and it was proved that there were no considerable differences between both strains. Monascus sp. 94–25 was a prototroph and had optimal growth temperature 34 o C. Investigation of the fermentation and assimilation capacity of both strains was performed. It was found that both of them assimilated well glucose, while highest fermentation ability was observed when grown on galactose. Similarly to the referent strain Monascus sp. 94–25 could grow on starch and protein containing natural substrates. Regarding the morphological and biochemical investigations the newly isolated strain 94–25 could be considered as Monascus purpureus. Intr...
Citrinin is a mycotoxin, which is produced by fungi belonging to the genus Monascus, known in bio... more Citrinin is a mycotoxin, which is produced by fungi belonging to the genus Monascus, known in biotechnology as producers of azaphilone pigments. The relation between biosynthesis of these secondary metabolites was investigated in different species of the genus Monascus in batch-culture at the following cultivation conditions: T = 28 °C, agitation 220 rpm, and a medium, which induce citrinin production, containing ethanol as a carbon source. The screening was carried out with 16 fungal strains and the biosynthesis of citrinin and pigments was monitored quantitatively at the standard conditions mentioned above. Some kinetic parameters of the process have been determined. The values of the growth yield coefficient YX/C were between 0.32 and 0.57. The amount of the extracellular red and orange pigments at the end of cultivation varied for the different strains between 0.09 and 1.33 OU/ mg dry weight, and 0.15 and 0.96 OU/mg dry weight, respectively. The amount of the total pigments meas...
Biotechnology & Biotechnological Equipment
Yeasts Saccharomyces cerevisiae, like other microbes in nature, respond to the unavailability of ... more Yeasts Saccharomyces cerevisiae, like other microbes in nature, respond to the unavailability of nutrients with entrance in quiescent/G0 state. These cells exist in non-dividing, latent form by mai...
Biotechnology & Biotechnological Equipment
The focus of the present study is to determine proteins responsible for the oxidative and toxic s... more The focus of the present study is to determine proteins responsible for the oxidative and toxic stress response in proliferating and stationary phase (G0) cultures. Therefore, the yeast Saccharomyc...
Biotechnology & Biotechnological Equipment
When starving, diploid Saccharomyces cerevisiae yeasts can enter into at least two stable nondivi... more When starving, diploid Saccharomyces cerevisiae yeasts can enter into at least two stable nondividing statessporulation or quiescenceand thus survive unfavorable conditions for long periods of time. However, which latent state will be preferred depends on numerous conditions. Here, we showed that budding yeasts can trigger transition into one or the other dormant state depending on the carbon source utilized. When fermentable carbon source (glucose) is present in the growth medium, the diploid S. cerevisiae entered quiescence. On the other hand, when cells were grown in the presence of the energy-rich respiratory carbon source ethanol, yeasts preferably formed ascospores. In both latent states a steady redox balance is maintained. Altogether, these findings strongly suggest that survival strategies in yeasts S. cerevisiae and transition into distinct differentiation programs depend on the cellular metabolic status.
Monascus sp. 94-25 strain was isolated from red rice with the purpose of red pigments submerged p... more Monascus sp. 94-25 strain was isolated from red rice with the purpose of red pigments submerged production. Morphological characterisation on the taxonomically important for the genus media, showed that the strain produced cleistothecia with oval ascospores and aleiroconidia. Comparison with a referent strain Monascus purpureus Went 109.07 was made and it was proved that there were no considerable differences between both strains. Monascus sp. 94-25 was a prototroph and had optimal growth temperature 34 o C. Investigation of the fermentation and assimilation capacity of both strains was performed. It was found that both of them assimilated well glucose, while highest fermentation ability was observed when grown on galactose. Similarly to the referent strain Monascus sp. 94-25 could grow on starch and protein containing natural substrates. Regarding the morphological and biochemical investigations the newly isolated strain 94-25 could be considered as Monascus purpureus.
Archives of Microbiology, Aug 26, 2010
The response of Saccharomyces cerevisiae to arsenic involves a large ensemble of genes, many of w... more The response of Saccharomyces cerevisiae to arsenic involves a large ensemble of genes, many of which are associated with glutathione-related metabolism. The role of the glutathione S-transferase (GST) product of the URE2 gene involved in resistance of S. cerevisiae to a broad range of heavy metals was investigated. Glutathione peroxidase activity, previously reported for the Ure2p protein, was unaVected in cell-free extracts of an ure2 mutant of S. cerevisiae. Glutathione levels in the ure2 mutant were lowered about threefold compared to the isogenic wild-type strain but, as in the wild-type strain, increased 2-2.5-fold upon addition of either arsenate (As V) or arsenite (As III). However, lack of URE2 speciWcally caused sensitivity to arsenite but not to arsenate. The protective role of URE2 against arsenite depended solely on the GSTencoding 3Ј-end portion of the gene. The nitrogen source used for growth was suggested to be an important determinant of arsenite toxicity, in keeping with non-enzymatic roles of the URE2 gene product in GATA-type regulation. Keywords Ure2 • Glutathione S-transferase • GATA regulation • Arsenic detoxiWcation Abbreviations GSTs Glutathione S-transferases NCR Nitrogen catabolite repression GPx Glutathione peroxidase Gdh1 NADPH-dependent glutamate dehydrogenase Gln1 Glutamine synthetase Gdh2 NAD +-dependent glutamate dehydrogenase Electronic supplementary material The online version of this article (
Journal of Cleaner Production
Biotechnology & Biotechnological Equipment
ABSTRACT
Journal of chromatography. B, Analytical technologies in the biomedical and life sciences
A new thermostable Cu/Zn SOD from a thermotolerant yeast strain Kluyveromyces marxianus NBIMCC 19... more A new thermostable Cu/Zn SOD from a thermotolerant yeast strain Kluyveromyces marxianus NBIMCC 1984 has been purified and characterized. The purification procedure comprises thermal treatment and dialysis, ion-exchange chromatography and chromatofocusing. The methodology is a rapid, efficient and highly specific, generating pure preparation (specific activity 996 U mg of protein(-1)) with a yield of 53%. The purified enzyme is a homodimer with Mw of 34,034 Da and has high N-terminal homology with other yeasts' Cu/Zn SOD enzymes. The protein is characterized with some unique features such as-thermostability (t(1/2) at 70 degrees C=30 min), pH stability in the alkaline range (7.5-8.5) and resistance to inhibitors and variety of chemicals. These characteristics reveal possibilities for wide practical application of K. marxianus Cu/Zn SOD enzyme.
Antonie van Leeuwenhoek, 2003
A characterization of a non-pigment producing mutant Monascus purpureus M12 compared with its par... more A characterization of a non-pigment producing mutant Monascus purpureus M12 compared with its parental strain Monascus purpureus Went CBS 109.07 has been performed aiming to investigate the relation between pigment biosynthesis and other characteristics of these fungi. A comparison has been made of morphological features, some physiological properties and biochemical activities of both strains. The albino mutant exhibits an anamorph life cycle, high conidia forming capability, slower radial growth rate and temperature sensitivity. The assimilation capacity of both strains for mono-, disaccharides and some alcohols is in the same range (Yx/c 0.2 - 0.35), while the red strain has a higher fermentation capacity. In a selected albino mutant, the growth rate, metabolic activity and capacity for production of typical for Monascus fungi secondary metabolites were reduced considerably. Hydrolytic activity towards natural substrates expressed through glucoamylase and protease was approximate...
Journal of chromatography. B, Analytical technologies in the biomedical and life sciences, 2009
A new thermostable Cu/Zn SOD from a thermotolerant yeast strain Kluyveromyces marxianus NBIMCC 19... more A new thermostable Cu/Zn SOD from a thermotolerant yeast strain Kluyveromyces marxianus NBIMCC 1984 has been purified and characterized. The purification procedure comprises thermal treatment and dialysis, ion-exchange chromatography and chromatofocusing. The methodology is a rapid, efficient and highly specific, generating pure preparation (specific activity 996 U mg of protein(-1)) with a yield of 53%. The purified enzyme is a homodimer with Mw of 34,034 Da and has high N-terminal homology with other yeasts' Cu/Zn SOD enzymes. The protein is characterized with some unique features such as-thermostability (t(1/2) at 70 degrees C=30 min), pH stability in the alkaline range (7.5-8.5) and resistance to inhibitors and variety of chemicals. These characteristics reveal possibilities for wide practical application of K. marxianus Cu/Zn SOD enzyme.
Biotechnology & Biotechnological Equipment, 2009
The primary structure of Cu/Zn-superoxide dismutase from Kluyveromyces marxianus NBIMCC 1984 was ... more The primary structure of Cu/Zn-superoxide dismutase from Kluyveromyces marxianus NBIMCC 1984 was elucidated by N-terminal sequence analysis of the intact protein and by determination of the amino acid sequences of tryptic peptides by MALDI-TOF-TOF tandem mass spectrometry. The molecular mass of one subunit of the homodimer SOD, containing 152 amino acid residues, was calculated to be 15858.3 Da while a value of 17096.63 Da was obtained by MALDI-TOF MS. This difference is explained by the presence of N-glycosylation of one linkage site,-Asn-Ile/Leu-Thr-, and a glycan chain with the structure Hex 5 GlcNAc 2. Glycosylation of K. marxianus superoxide dismutase is a post-translational modification. Recent developments in mass spectrometry have enabled detailed structural analyses of covalent modifications of proteins. Therefore, in this paper, we introduce a covalent modification of Cu/Zn-SOD from K. marxianus NBIMCC 1984, by analysis of the enzymatic liberated N-glycan from the enzyme using MALDI-TOF and tandem mass spectrometry on a Q-Trap mass spectrometer. This is the first report of the structure of the oligosaccharide of a naturally-glycosylated superoxide dismutase, determined by mass spectrometry.
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Papers by Anna Kujumdzieva