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Sergei I. Fokin Ewa Przybo Sergei M. Chivilev Cora L. Beier Matthias Horn Bogumila Skotarczak Beata Wodecka Masahiro Fujishima 《European journal of protistology》2004,40(3):225-243
Paramecium schewiakoffi sp. nov. is described from a pond in Shanghai, China. It is a freshwater species belonging to the “aurelia” subgroup of the genus. It is of similar size and shape to P. jenningsi, but has a single large micronucleus of the “chromosomal” morphological type, while P. jenningsi has two smaller micronuclei. The general morphology, morphometric characteristics and nuclear reorganization pattern, a random amplified polymorphic DNA (RAPD) fingerprint pattern, and the small subunit rRNA gene sequence are presented for the species. Comparison of P. schewiakoffi with the other species of Paramecium indicates that it is a valid new species of the genus. Geographical locations reported for many Paramecium species do not support the theory that all ciliates have a cosmopolitan distribution. It is proposed that, in an extension of Jankowski's earlier suggestion, the genus Paramecium should be subdivided into four subgenera: Chloroparamecium, Helianter, Cypriostomum and Paramecium, on the basis of morphometric, biological and molecular differences. 相似文献
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Matylda Sidwa-Gorycka Aleksandra Krolicka Aleksandra Orlita Edmund Malinski Marek Golebiowski Jolanta Kumirska Agnieszka Chromik Edyta Biskup Piotr Stepnowski Ewa Lojkowska 《Plant Cell, Tissue and Organ Culture》2009,97(1):59-69
Ruta graveolens L. is a source of pharmacologically active compounds such as coumarins, furanocoumarins and furoquinolone alkaloids. Hypocotyls,
callus and shoots of R. graveolens were inoculated with bacteria from two Agrobacterium rhizogenes strains. Hairy root cultures were established after inoculation of hypocotyls with wild A. rhizogenes strain LBA 9402. The transgenic nature of the regenerated tissue was confirmed by PCR amplification. Coumarins, furanocoumarins
and alkaloids present in the hairy root tissue were identified by GC and GC-MS and compared with those present in in vitro
shoot cultures. The level of pinnarin and rutacultin, bergapten, isopimpinelin and xanthotoxin was approximately twofold higher
in hairy root than in shoot cultures. Two additional coumarins: osthole and osthenol, never been found in R. graveolens, were identified in hairy root tissue. Besides coumarins, alkaloids were identified: dictamnine, skimmianine, kokusaginine,
rybalinine and an isomer of rybalinine. The levels of nearly all coumarins and alkaloids in hairy roots cultured in the darkness
were higher than those accumulated under a photoperiod mode. 相似文献
996.
Hardt M Thomas LR Dixon SE Newport G Agabian N Prakobphol A Hall SC Witkowska HE Fisher SJ 《Biochemistry》2005,44(8):2885-2899
Saliva plays many biological roles, from lubrication and digestion to regulating bacterial and leukocyte adhesion. To understand the functions of individual components and families of molecules, it is important to identify as many salivary proteins as possible. Toward this goal, we used a proteomic approach as the first step in a global analysis of this important body fluid. We collected parotid saliva as the ductal secretion from three human donors and separated the protein components by two-dimensional SDS-polyacrylamide gel electrophoresis (2D SDS-PAGE). Proteins in gel spots were identified by peptide mass fingerprinting, and the results were confirmed by tandem mass spectrometry of selected peptides. Complementing this approach we used ultrafiltration to prepare a low-molecular-weight fraction of parotid saliva, which was analyzed directly or after reversed phase high-performance liquid chromatography separation by using mass spectrometric approaches. MS analyses of 2D SDS-PAGE spots revealed known components of saliva, including cystatins, histatins, lysozyme, and isoforms and/or fragments of alpha-amylase, albumin, and proline-rich proteins. We also discovered novel proteins, such as several isoforms of Zn-alpha-2-glycoprotein and secretory actin-binding protein. MS analyses of the ultrafiltrate showed that the low-molecular-weight fraction of parotid saliva was peptide-rich, with novel fragments of proline-rich proteins and histatins in abundance. Experiments using Candida albicans as the test organism showed that at least one of the novel peptides had antifungal activity. Our results show that saliva is a rich source of proteins and peptides that are potential diagnostic and therapeutic targets. 相似文献
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Inhibition of de novo pyrimidine synthesis in growing potato tubers leads to a compensatory stimulation of the pyrimidine salvage pathway and a subsequent increase in biosynthetic performance 下载免费PDF全文
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Stanisław Weidner Magdalena Karamać Ryszard Amarowicz Ewa Szypulska Aleksandra Gołgowska 《Acta Physiologiae Plantarum》2007,29(3):283-290
The research focused on the changes of phenolic compounds as well as their antiradical activity and reducing power isolated
from Amur grape (Vitis amurensis) seeds during germination under optimal conditions and under osmotic stress. The seeds were found to contain tannins, (+)
catechin, (−) epicatechin, and gallic acid (in free, ester- and glycoside-bound forms). Extracts from the seeds were also
shown to contain two other phenolic acids: caffeic and p-coumaric acids, in very low levels. During a 3-day seed germination test under osmotic stress (−0.5 MPa), the content of
total phenolics, tannins and phenolic acids declined as compared to the control. However, seed germination under stress conditions
led to a significant increase in the amount of catechins. Because catechin is the one of the units in condensed tannins, its
dynamic increase during seed germination may be involved in metabolism of tannins under osmotic stress. It is also likely
that the synthesis of catechins is greater under stress conditions and these compounds may be engaged in the process of acclimatization
of grapevines to stress conditions. The content of total phenolic compounds in seed extracts is positively correlated with
their antioxidant properties. The extracts from seeds germinated under optimal conditions exhibited strong antiradical properties
against the DPPH (2,2-diphenyl-1-picrylhydrazyl) radical as well as reducing power. As regards the extracts from grape seeds
germinated under osmotic stress, this capability was much weaker. The research demonstrated that antioxidants could interfere
with the oxidation process induced by various stresses by acting as oxygen scavengers, therefore the tolerance to drought
stress might be correlated with an increase in the antioxidant potential. 相似文献