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991.
Szweda P Schielmann M Milewski S Frankowska A Jakubczak A 《Polish journal of microbiology》2012,61(1):65-69
The aim of the study was phenotypic and genotypic analysis of 132 S. aureus strains isolated from mastitis in eastern Poland in respect to their biofilm formation ability. The analysis of the size polymorphism of fragment X in the gene encoding protein A (spa) revealed high genetic differentiation of the analyzed group of isolates. The ability of biofilm formation by the isolates was tested using two phenotypic methods. The Congo Red plate assay was found to be irreproducible and very subjective. More objective results were obtained using the spectrophotometric, microtiter plate assay. Most of the isolates, namely 76/132 (57.6 %) were classified as biofilm producers depending on the value of absorbance in the microtiter plate test. All of the isolates tested were found to possess both icaA and icaD genes, while the bap gene was absent in all strains. 相似文献
992.
Małecki PH Rypniewski W Szymański M Barciszewski J Meyer A 《Biochimica et biophysica acta》2012,1824(2):334-338
The crystal structure of the ribosome inhibiting protein Mistletoe Lectin I (ML-I) derived from the European mistletoe, Viscum album, in complex with kinetin has been refined at 2.7? resolution. Suitably large crystals of ML-I were obtained applying the counter diffusion method using the Gel Tube R Crystallization Kit (GT-R) on board the Russian Service Module on the international space station ISS within the GCF mission No. 6, arranged by the Japanese aerospace exploration agency (JAXA). Hexagonal bi-pyramidal crystals were grown during three months under microgravity. Before data collection the crystals were soaked in a saturated solution of kinetin and diffraction data to 2.7? were collected using synchrotron radiation and cryogenic techniques. The atomic model was refined and revealed a single kinetin molecule in the ribosome inactivation site of ML-I. The complex demonstrates the feasibility of mistletoe to bind plant hormones out of the host regulation system as part of a self protection mechanism. 相似文献
993.
Jerzy Wielbo Dominika Kidaj Piotr Koper Agnieszka Kubik-Komar Anna Skorupska 《Central European Journal of Biology》2012,7(1):13-24
Background
Rhizobium leguminosarum bv. viciae (Rlv) is a soil bacterium which can form nitrogen-fixing symbiotic relationships with leguminous plants. Numerous rhizobial strains found in soils compete with each other. Competition can occur both during the saprophytic growth phase in the rhizosphere and inside plant tissues, during the symbiotic phase. Competition is important as it may affect the composition of rhizobial populations present in the soil and in the root nodules of plants. 相似文献994.
Piotr Czyżowski Leszek Drozd Mirosław Karpiński Katarzyna Tajchman Małgorzata Goleman Justyna Wojtaś Damian Zieliński 《Biologia》2018,73(2):185-189
Populations of game are not confined to single ecosystems but function within higher-order units, e.g. ecological landscape. The basis for the establishment of the hunting complexes was the assumption that the existing game hunting grounds, i.e. the basic units implementing game management, are too small and do not cover the natural areas inhabited by game populations. Roe deer are flexible species and easily adapt to various site conditions, so they inhabit many different habitats, from large forest complexes, through small in-field tree stands and shrubs, to treeless grounds and field monocultures. The aim of the study was to determine a possible impact of environmental conditions prevailing in the hunting complexes of the Regional Directorate of State Forests (RDLP in Lublin) on the ontogenetic quality of roe deer. The study was conducted on 518 European roe deer (Capreolus capreolus) aged from 4 to 7 years (379 bucks and 139 does) harvested within hunting seasons 2010/2011–2013/2014. The results have shown that animals originating from areas with greater forest cover and denser stands are characterised by lower values of the mean ontogenetic quality parameters (carcase weight, kidney fat index, chest girth, weight of antlers) in comparison with animals from typical agricultural areas with fragmented forest complexes. These results indicate that, even in the case of such a eurytopic species as the roe deer, the ontogenetic quality differs between individual hunting complexes. The study has proved that strategies for hunting management of the roe deer should take into account the impact of the landscape structure, which provides a rationale behind creation of hunting complexes. 相似文献
995.
Ronghui Pan Sigrun Reumann Piotr Lisik Stefanie Tietz Laura J. Olsen Jianping Hu 《植物学报(英文版)》2018,60(11):1028-1050
Peroxisomes compartmentalize a dynamic suite of biochemical reactions and play a central role in plant metabolism, such as the degradation of hydrogen peroxide,metabolism of fatty acids, photorespiration, and the biosynthesis of plant hormones. Plant peroxisomes have been traditionally classified into three major subtypes, and in-depth mass spectrometry(MS)-based proteomics has been performed to explore the proteome of the two major subtypes present in green leaves and etiolated seedlings. Here, we carried out a comprehensive proteome analysis of peroxisomes from Arabidopsis leaves given a 48-h dark treatment.Our goal was to determine the proteome of the third major subtype of plant peroxisomes from senescent leaves, and further catalog the plant peroxisomal proteome. We identifieda total of 111 peroxisomal proteins and verified the peroxisomal localization for six new proteins with potential roles in fatty acid metabolism and stress response by in vivo targeting analysis. Metabolic pathways compartmentalized in the three major subtypes of peroxisomes were also compared, which revealed a higher number of proteins involved in the detoxification of reactive oxygen species in peroxisomes from senescent leaves. Our study takes an important step towards mapping the ful function of plant peroxisomes. 相似文献
996.
Treacher Collins syndrome (TCS) is associated with an abnormal differentiation of the first and second pharyngeal arches during fetal development. This causes mostly craniofacial deformities, which require numerous corrective surgeries. TCS is an autosomal dominant disorder and it occurs in the general population at a frequency of 1 in 50,000 live births. The syndrome is caused by mutations in the TCOF1 gene, which encodes the serine/alanine-rich protein named Treacle. Over 120 mutations of the TCOF1 gene responsible for TCS have been described. About 70% of recognized mutations are deletions, which lead to a frame shift, formation of a termination codon, and shortening of the protein product of the gene. Herewith, a new heterozygotic insertion, c.484_668ins185bp, was described in two monozygotic twin sisters suffering from TCS. This mutation was absent in their father, brother, and uncle, indicating a de novo origin. The insertion causes a shift in the reading frame and premature termination of translation at 167 aa. The novel insertion is the longest ever found in the TCOF1 gene and the only one found among monozygotic twin sisters. 相似文献
997.
NM Cordina CK Liew DA Gell PG Fajer JP Mackay LJ Brown 《Protein science : a publication of the Protein Society》2012,21(9):1376-1387
Cardiac troponin C (cTnC) is the calcium binding subunit of the troponin complex that triggers the thin filament response to calcium influx into the sarcomere. cTnC consists of two globular EF-hand domains (termed the N- and C-domains) connected by a flexible linker. While the conformation of each domain of cTnC has been thoroughly characterized through NMR studies involving either the isolated N-domain (N-cTnC) or C-domain (C-cTnC), little attention has been paid to the range of interdomain orientations possible in full-length cTnC that arises as a consequence of the flexibility of the domain linker. Flexibility in the domain linker of cTnC is essential for effective regulatory function of troponin. We have therefore utilized paramagnetic relaxation enhancement (PRE) NMR to assess the interdomain orientation of cTnC. Ensemble fitting of our interdomain PRE measurements reveals that isolated cTnC has considerable interdomain flexibility and preferentially adopts a bent conformation in solution, with a defined range of relative domain orientations. 相似文献
998.
Oleg V. Askeyev Tim H. Sparks Igor V. Askeyev Piotr Tryjanowski 《Central European Journal of Biology》2009,4(4):595-602
The timing of when migrant birds return to breed is a key component of studies of the impact of climate change upon bird populations.
However, such data are not distributed evenly across the World, and in the Northern Hemisphere are underrepresented in Asia
and the east of Europe. Therefore, to help rectify this bias, we analysed first arrival dates (FAD) of four species of Sylvia warblers (Blackcap Sylvia atricapilla, Whitethroat S.communis, Lesser Whitethroat S.curruca and Garden Warbler S.borin) collected in the Tatarstan Republic of Russia between 1957 and 2008. Over the whole period the species returned to their
breeding sites between three and six days earlier; these trends were significant except for Whitethroat. Advances in arrival
were especially apparent in the two earlier species, Blackcap and Lesser Whitethroat, mainly because local temperatures for
March had risen substantially. Except for Whitethroat, FADs were significantly related to temperatures in the African wintering
ground and/or in Tatarstan. Whilst significant correlations occurred between FADs of some of the species, there was considerable
variability in these relationships indicating a species-specific response to rising temperatures. Changes in FADs in this
eastern extremity of Europe were smaller than in Central and Western Europe. 相似文献
999.
1000.