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21.
We propose a new set of approaches, which allow identifying the primary enzymes of glyphosate (N-phosphonomethyl-glycine) attack, measuring their activities, and quantitative analysis of glyphosate degradation in vivo and in vitro. Using the developed approach we show that glyphosate degradation can follow different pathways depending on physiological characteristics of metabolizing strains: in Ochrobactrum anthropi GPK3 the initial cleavage reaction is catalyzed by glyphosate-oxidoreductase with the formation of aminomethylphosphonic acid and glyoxylate, whereas Achromobacter sp. MPS12 utilize C-P lyase, forming sarcosine. The proposed methodology has several advantages as compared to others described in the literature.  相似文献   
22.
This paper present the map of polytene chromosomes and inversion polymorphism of widely distributed Chironomidae species, Camptochironomus tentans, from the most western locality of Russia--Kaliningrad city. Chromosomes banding pattern is designated according to Beermann, 1955. Only one larva (2.9%) had a standard banding pattern, and karyotypes of the rest (97.1%) were polymorphic. We have found 2.0 heterozygous inversions per individual, and the frequency of hetero- and homozygous inversions, taken together, amounted to 2.2 per individual. 17 inversion banding patterns and 20 genotypic combinations of these patterns were found. It was shown that the most frequent inversions in this population were identical to these in European populations.  相似文献   
23.
A method of rapid freezing in supercooled Freon 22 (monochlorodifluoromethane) followed by cryoultramicrotomy is described and shown to yield ultrathin sections in which both the cellular ultrastructure and the distribution of diffusible ions across the cell membrane are preserved and intracellular compartmentalization of diffusabler ions can be quantitated. Quantitative electron probe analysis (Shuman, H., A.V. Somlyo, and A.P. Somlyo. 1976. Ultramicros. 1:317-339.) of freeze-dried ultrathin cryto sections was found to provide a valid measure of the composition of cells and cellular organelles and was used to determine the ionic composition of the in situ terminal cisternae of the sarcoplasmic reticulum (SR), the distribution of CI in skeletal muscle, and the effects of hypertonic solutions on the subcellular composition if striated muscle. There was no evidence of sequestered CI in the terminal cisternae of resting muscles, although calcium (66mmol/kg dry wt +/- 4.6 SE) was detected. The values of [C1](i) determined with small (50-100 nm) diameter probes over cytoplasm excluding organelles over nuclei or terminal cisternae were not significantly different. Mitochondria partially excluded C1, with a cytoplasmic/ mitochondrial Ci ratio of 2.4 +/- 0.88 SD. The elemental concentrations (mmol/kg dry wt +/- SD) of muscle fibers measured with 0.5-9-μm diameter electron probes in normal frog striated muscle were: P, 302 +/- 4.3; S, 189 +/- 2.9;C1, 24 +/- 1.1;K, 404 +/- 4.3, and Mg, 39 +/- 2.1. It is concluded that: (a) in normal muscle the "excess CI" measured with previous bulk chemical analyses and flux studies is not compartmentalized in the SR or in other cellular organelles, and (b) the cytoplasmic C1 in low [K](0) solutions exceeds that predicted by a passive electrochemical distribution. Hypertonic 2.2 X NaCl, 2.5 X sucrose, or 2.2 X Na isethionate produced: (a) swollen vacuoles, frequently paired, adjacent to the Z lines and containing significantly higher than cytoplasmic concentrations of Na and Cl or S (isethionate), but no detectable Ca, and (b) granules of Ca, Mg, and P = approximately (6 Ca + 1 Mg)/6P in the longitudinal SR. It is concluded that hypertonicity produces compartmentalized domains of extracellular solutes within the muscle fibers and translocates Ca into the longitudinal tubules.  相似文献   
24.
25.
Penicillium citrinum VKM F-1079 was found to produce clavine ergot alkaloids and citrinin, a secondaryO-heterocyclic metabolite. Citrinin was produced in the idiophase, whereas the production of ergot alkaloids paralleled fungal growth. The addition of manganese ions to the growth medium stimulated the biosynthesis of both citrinin and ergot alkaloids. Zinc ions stimulated only citrinin synthesis. The presence of these microelements in the growth medium influenced the proportion between the ergot alkaloids synthesized. Copper, manganese, and iron ions slightly affected fungal growth and alkaloid production. The effect of microelements on the main kinetic parameters of growth and alkaloid production was studied.  相似文献   
26.
A screening of lignin-degrading basidial fungi that can grow in the presence of thiomorpholine derivatives (the mixture of 1,4-perhydrothiazines) has been performed. Strain Bjerkandera adusta VKM F-3477 was shown to have the maximal rate of growth in the presence of these compounds, and its capacity for thiomorpholine degradation was studied. The methods of quantitative analysis of thiomorpholine and its degradation products on the basis of thin layer chromatography and high-performance liquid chromatography were developed. It was shown that the B. adusta strain did not utilize thiomorpholine as a carbon source but transformed it into thiomorpholine sulfoxide that accumulated in the medium. Mn peroxidase produced by B. adusta in the course of thiomorpholine transformation is not directly involved in its oxidation.  相似文献   
27.
New spatial of clavine alkaloids, distinguished by low chromatographical mobility, have been isolated from the collection and mutant strain of Penicillium roquefortii, in addition to alkaloids roquefortine, 3,12-dihydroroquefortine, isofumigaclavines A and B, festuclavine, and chanoclavine-I, characteristic of this fungal species. In has been shown that the collection strain produces isomers of agroclavine and epoxyagroclavine, and the mutant strain produces isomers of fumigaclavines A and B, festuclavine, and chanoclavine.  相似文献   
28.
The type strains Penicillium clavigerum VKM F-447 and P. commune VKM F-3233 are found to produce fumigaclavines A and B. Of the seven other strains of these species, only two strains, P. commune VKM F-3088 and F-3491, possess the ability to synthesize these alkaloids. It is suggested that the five other strains under study either lost such an ability or require very specific conditions for the synthesis of these alkaloids.  相似文献   
29.
Fungi of the species Penicillium piscarium produced diketopiperazine alkaloids (isorugulosuvine, puberuline, verrucosine, prolyltryptophanyldiketopiperazine, 12,13-dehydroprolyltryptophanyldiketopiperazine, fellutanine A, phenylalanylphenylalanyldiketopiperazine, as well as roquefortine and 3,12-dihydroroquefortine whose precursors are tryptophan, phenylalanine, leucine, proline, and histidine.  相似文献   
30.
Fungi of the speciesPenicillium piscarium produced diketopiperazine alkaloids (isorugulosuvine, puberuline, verrucosine, prolyltryptophanyldiketopiperazine, 12,13-dehydroprolyltryptophanyldiketopiperazine, fellutanine A, phenylalanylphenylalanyldiketopiperazine, as well as roquefortine and 3,12-dihydroroquefortine, whose precursors are tryptophan, phenylalanine, leucine, proline, and histidine.  相似文献   
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