Isolation and Characterization of Tightly Coupled Mitochondria from Wild Type and nap Mutant Neurospora crassa

A fast and reproducible procedure was elaborated for isolation of tightly coupled mitochondria from wild type and nap mutant Neurospora crassa cells harvested at different growth stages. The isolated mitochondrial preparations had controlled metabolic states and were tightly coupled, i.e., displayed good respiratory control and had close to the theoretically expected maximal ADP/O ratios upon oxidation of Krebs cycle intermediates and exogenous NADH. They contained the fully competent respiratory chain with all three points of energy conservation. Oxidation of all examined substrates by mitochondria from both wild type and mutant cells was mediated by two alternative terminal oxidative systems, albeit to varying extent, with the more pronounced engagement of the alternative oxidase in the stationary growth phase and with a minor contribution of this non-phosphorylating pathway in the substrate oxidation by mutant mitochondria. Oxidation of NAD-dependent substrates by mitochondria from the two cell types was accommodated via both rotenone-sensitive and rotenone-insensitive pathways, while the level of rotenone-insensitive pathway in mutant cells was lower than in wild type cells. It is suggested that a more limited contribution of alternative non-phosphorylating oxidative pathways to the total respiration in mutant cells, as compared with wild type cells, could, at least partially, explain an elevated ATP level in these cells. However, the absence of principal differences in the arrangement of the respiratory chain in mitochondria of wild type and mutant cells implies that the elevated ATP level in the nap mutant is largely related to reduced ATP expenses for transport processes in these cells.     

The immunophenotypic and cytogenetic characteristics of the blast cells in subvariants of acute myeloid leukemia

The results of study of morpho-cytochemical peculiarities, antigenic profile and peripheric blood and/or bone marrow blast cell karyotype of 21 patients with acute myeloid leukemia are presented. Hemopoietic cell immunophenotyping was carried out with the use of cytofluorometer FACScan and chromosome cytogenetic analysis with the use of analyzer "Metascan". It has been shown that in the AML M1 blast cell plasmatic membrane carries pan-myeloid CD33 and CD13 antigens, the last having high density of expression, and the CD38 antigen, which is a myeloid cell-precursor marker. In these patients tetraploidy, being the testimony of karyotype change, has been ascertained. It has been found out that the AML M2 blasts, except pan-myeloid antigens, express the cell proliferation CD71 marker. Blast cell karyotype peculiarities typical for this leukemia sub-variant have been revealed. In patients with the AML M4 in 3 of 6 cases an anomalous karyotype has been found. It has been also shown that the CD14 antigen, and rather its percentage in blast total population, is the differential-diagnostic criterion for the AML M4 and M5.     

Reproduction of the trematode Echinostoma caproni parthenites (Digenea: Echinostomatidae)

Dynamics of the reproduction in the trematode Echinostoma caproni parthenites (Echinostomatidae) was observed. Early laying and maturation of the generative cells are for the first time shown to be characteristic for all parthenogenetic generations. Really the process of reproduction had been finishing to the beginning of the generating of new age by parthenites. Mother sporocysts, as well as redia of different generations, in fact stop producing new generative cells with the beginning of the generating of new age, and assume the function of a brood pouch. This feature was considered previously as peculiar mainly to mother sporocysts. Data on the autotomy of the anterior body end in mother sporocysts are verified. In our opinion, these data are an evidence of an early manifestation of the evolutionary trend to the morpho-functional regress and disintegration of the parasitic stage of mother sporocyst.     

Biostratigraphical analysis of the Moscovian–Kasimovian transition at the neostratotype of Kasimovian Stage (Afanasievo section, Moscow Basin, Russia)

The Afanasievo Quarry, approximately 90 km southeast of Moscow and about 5 km southwest of Voskresensk, starts with Late Moscovian limestone of the Peski Formation, which is overlain by shallow-water carbonates of the Krevyakinian Horizon (Substage) (Suvorovo and Voskresensk formations) and the lower part of the Khamovnikian Horizon (Substage) (Ratmirovo and Neverovo formations). These rocks were formed under the strong influence of glacio-eustatic sea-level fluctuations and are separated by the palaeosol horizons and minor stratigraphic gaps. The Moscovian–Kasimovian transition interval contains fusulinids, brachiopods, bryozoans, corals, and conodonts. It was recently proposed [Villa, E., Task Group, 2005. Report of the Task Group to establish GSSPs at the Moscovian–Kasimovian and Kasimovian-Gzhelian boundaries. Newsletter on Carboniferous Stratigraphy 23, 9–10] that the appearance of the conodont Idiognathodus sagittalis Kozitskaya is one of the best markers for definition of the base of the Kasimovian on the global chronostratigraphic scale. The first appearance of this species is 2 m above the base of Neverovo Formation, and is close to the first appearance of the fusulinid Montiparus in the section. The possible ancestor of I. sagittalis occurs in the lower Suvorovo Formation, but is more abundant and more advanced in the middle to upper parts of the Voskresensk Formation. This lineage has potential for defining a GSSP at the first appearance of I. sagittalis.     

Increasing viability of the crustacean Ceriodaphnia affinis Lilljeborg using 10-(2′, 3′-dimethylhynonil-6′)-deciltriphenylphosphonium bromide

The influence of low concentrations of 10-(2′, 3′-dimethylhynonil-6′)-deciltriphenylphosphonium bromide on the laboratory culture of the crustaceans Ceriodaphnia affinis has been investigated. The increase of average and maximum lifespan, as well as stimulation of heredity, has been found out. Possible mechanisms of this phenomenon have been analyzed.     

The use of 1H-NMR-spectroscopy for the study of peptide degradation by angiotensin-converting enzyme

A new method for continuous registration of enzymatic hydrolysis of peptides involving 1H-NMR spectroscopy was developed. The advantages of the method were demonstrated, using dalargin (Tyr-D-Ala-Gly-Phe-Leu-Arg) hydrolysis catalyzed by human kidney angiotensin-converting enzyme as an example. It was shown that the maximal activity of the enzyme towards dalargin is observed at pH 7.8; Km is 0.35 mM. The enzyme is inhibited by the substrate (Kd = 0.55 mM). Cl- do not influence the catalytic activity of the enzyme with respect to dalargin. The stereospecificity of the angiotensin-converting enzyme towards dalargin diasteriomers was studied.     

Phylogenetic analysis of the outer-membrane-protein genes of Chlamydiae, and its implication for vaccine development

Examination of 18 complete and 6 partial sequences of the major outer- membrane protein from 24 chlamydiae isolates was used to reconstruct their evolutionary relationships. From this analysis, assuming that the clades with 100% bootstrap support are correct, come the following conclusions: (1) The tree of these sequences is not congruent with the phylogeny of the hosts, and thus host switching would seem to have occurred, thereby limiting the extent to which there has been coevolution of parasite and host. (2) The tree is also noncongruent with clustering by type of cell infected, thereby limiting the extent to which there has been coevolution of parasite and the cell type that it infects. (3) The tree is also noncongruent with clustering by the organ infected (eyes or genitalia), thereby limiting the extent to which there has been coevolution of parasite and the organ that it infects. (4) The tree is also noncongruent with genital strains arising from lymphogranuloma venereum strains. (5) The tree is also noncongruent with the geographic site at which the isolates were obtained, thereby limiting the extent of divergence explained by geographic separation. (6) There are estimated to be 185 amino acid positions that are invariable (as opposed to unvaried) in the major outer-membrane protein. There are 10 unvaried positions in the variable domains, of which 9 appear to be invariable, giving some reason to hope that development of a vaccine might be possible. (7) The rate of change of this protein is too small to see increased divergence over the time span of isolation of these genes, giving hope to any vaccine having longevity. Bootstrapping supports those portions of the tree on which the first five conclusions above depend. The picture that these results provide is more one of pathogen versatility than one of coevolutionary constraints. In addition, we examined 10 60-KDa, outer-membrane protein- 2 genes, all but one of which were from these same strains. The tree was not, among the trachomatis strains, congruent with the major-outer- membrane protein tree, suggesting that gene exchange could be occurring among strains. Moreover, there is an apparent slowdown in divergence in this gene, among the trachomatis strains.      

Phytases and the Prospects for Their Application (Review)

Phytases from plants and microorganisms release phospates from poorly soluble phytates, making the phospates more accessible. In this review, some features and biochemical properties of phytases, as well as the areas and prospects for their use, are under discussion. The introduction of phytases into the fodder for food-producing animals increases the product yield without any additional expenses for mineral phosphates. The presense of phytases in the soils reduces the risk of water eutrophication.