The Leishmania donovani complex: genotypes of five metabolic enzymes (ICD, ME, MPI, G6PDH, and FH), new targets for multilocus sequence typing.

Flagellates of the Leishmania donovani complex are causative agents of human cutaneous and visceral leishmaniasis. The complex is comprised of L. donovani, Leishmania infantum and Leishmania archibaldi, although the latter is not now considered to be a valid species. Morphological distinction of Leishmania species is impractical, so biochemical, immunological and DNA-based criteria were introduced. Multilocus enzyme electrophoresis (MLEE) is the present gold standard. We have sequenced the genes encoding five metabolic enzymes used for MLEE, both to resolve the DNA diversity underlying isoenzyme mobility differences and to explore the potential of these targets for higher resolution PCR-based multilocus sequence typing. The genes sequenced were isocitrate dehydrogenase, malic enzyme, mannose phosphate isomerase, glucose-6-phosphate dehydrogenase, and fumarate hydratase, for 17 strains of L. infantum, seven strains of L. donovani, and three strains of L. archibaldi. Protein mobilities predicted from amino acid sequences did not always accord precisely with reported MLEE profiles. A high number of heterozygous sites was detected. Heterozygosity was particularly frequent in some strains and indirectly supported the presence of genetic exchange in Leishmania. Phylogenetic analysis of a concatenated alignment based on a total of 263 kb protein-coding sequences showed strong correlation of genotype with geographical origin. Europe and Africa appear to represent independent evolutionary centres

THE CONTENT OF SENSORY ACTIVE COMPOUNDS AND FLAVOUR OF SEVERAL TYPES OF YOGURTS

Abstract VÍTOVÁ, E., BABÁK, L., MOKÁŇOVÁ, R., HÝSKOVÁ, E., ZEMANOVÁ, J.: The content of sensory active compounds and fl avour of several types of yogurts. Acta univ. agric. et silvic. Mendel. Brun., 2010, LVIII, No. 5, pp. 407-412 The aim of this work was to identify and quantify several sensory active compounds in various types of yogurts using gas chromatography and simultaneously to judge their infl uence on fl avour of yogurts using sensory analysis. In total 4 types of white and 10 types of fl avoured yogurts (creamy and low-fat) with various fl avourings, produced in Dairy Valašské Meziříčí, Ltd., were analysed. The highest content of sensory active compounds (P < 0.05) was found in strawberry yogurts, with high amount of ethyl butyrate. Excepting ethanol no signifi cant diff erences (P < 0.05) were found between low-fat and creamy varieties. The total content of sensory active compounds in white yogurts was signifi cantly (P < 0.05) lower than in fl avoured fruit types. The highest content was in low-fat and lowest in white bio yoghurts. Flavour of yogurts was evaluated sensorially using scale and ranking test. All creamy yogurt varieties were evaluated as signifi cantly (P < 0.05) more tasty than low-fat ones. Similarly in case of white yogurts creamy yogurts were evaluated as the most tasty and low-fat ones as the worst. Bio yogurts were evaluated equally tasty as classic yogurts with the same fat content. yogurt, fl avour, sensory active compounds, GC, SPME, sensory analysi

Genetic polymorphism within the leishmania donovani complex: correlation with geographic origin.

Random amplified polymorphic DNA (RAPD) was used to detect intraspecific diversity for the Leishmania donovani complex. Fifty-two decameric to 21-meric primers of arbitrary sequence were applied to 15 strains that belong to nine zymodemes. Strains belonging to the species L. major and L. tropica were used as outgroups. A total of 902 amplicons generated by RAPD were scored. Most primers produced species-specific profiles, only 0.6% amplicons were shared by all species, while 4.3% amplicons were common for all 15 strains of the L. donovani complex. Well-supported trees have been constructed, which show a rather strong correlation between the genetic polymorphism of studied strains and their geographic origin. In all obtained trees, L. infantum was paraphyletic. The RAPD profiles suggest that MON-30 belongs to L. donovani. Moreover, the genetic distance between the L. archibaldi strain and other leishmanias does not warrant existence of a separate species

Initial characterization of human DHRS1 (SDR19C1), a member of the short chain dehydrogenase/reductase superfamily.

Many enzymes from the short-chain dehydrogenase/reductase superfamily (SDR) have already been well characterized, particularly those that participate in crucial biochemical reactions in the human body (e.g. 11 beta-hydroxysteroid dehydrogenase 1, 17 beta-hydroxysteroid dehydrogenase 1 or carbonyl reductase 1). Several other SDR enzymes are completely or almost completely uncharacterized, such as DHRS1 (also known as SDR19C1). Based on our in silico and experimental approaches, DHRS1 is described as a likely monotopic protein that interacts with the membrane of the endoplasmic reticulum. The highest expression level of DHRS1 protein was observed in human liver and adrenals. The recombinant form of DHRS1 was purified using the detergent ndodecy1-beta-D-maltoside, and DHRS1 was proven to be an NADPH-dependent reductase that is able to catalyse the in vitro reductive conversion of some steroids (estrone, androstene-3,17-dione and cortisone), as well as other endogenous substances and xenobiotics. The expression pattern and enzyme activities fit to a role in steroid and/or xenobiotic metabolism; however, more research is needed to fully clarify the exact biological function of DHRS1