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951.
Zabłotna Ewa Kaźmierczak Katarzyna Jaśkiewicz Anna Kupryszewski Gotfryd Rolka Krzysztof 《International journal of peptide research and therapeutics》2002,9(2-3):131-134
Summary Trypsin inhibitor SFTI-1 isolated from sunflower seeds (comprising 14 amino acid residues and two cycles: head-to-tail cyclisation
and disulfide bridge) is the smallest naturally occurring plant serine proteinase inhibitor. In our recent paper we have shown
that the elimination head-to-tail cyclisation did not change trypsin inhibitory activity as judged by measured by association
equilibrium constants K
a
. The removal of disulfide bridge produced 2.4-fold lower activity. In the present paper we described chymotrypsin inhibitory
activity. SFTI-1 inhibits significantly lower bovine α-chymortypsin (K
a
=(5.20±1.56)×106 M−1). The activity of the analogue with disulfide bridge only was practically the same, whereas the K
a
value determined for homodetic peptide was almost 3-fold lower. Considering the results obtained and the recent literature
data we postulate the lower inhibitory activity against both enzymes of the analogue with head-to-tail cyclisation only reflect
its lower proteolytic stability. 相似文献
952.
Year-round monitoring of five Antarctic pinnipeds was conducted in Admiralty Bay from 1988 up to 2000. Two breeding species: southern elephant sealsMirounga leonina (Linnaeus, 1758) and Weddell sealsLeptonychotes weddellii (Lesson, 1826), were present throughout the year. Three other species: crabeater seals Lobodon carcinophagus (Hobron and Jacquinot, 1842), leopard sealsHydrurga leptonyx (Blainville, 1820), and Antarctic fur sealsArctocephalus gazella (Peters, 1875) visited the area only for short periods. During this study, the abundance of elephant seals was stable, whereas those of Weddell and crabeater seals declined. Leopard seals numbers fluctuated irregularly. We detected a possible immigration from South Georgia: of a stable magnitude for elephant seals, and of variable magnitude, depending on food accessibility, for Antarctic fur seals. We found a strong recurrence of the spatial distributions of elephant, Weddell, and Antarctic fur seals in the 13 oases on the shore of Admiralty Bay. Annual distribution patterns were characteristic for each species. The innermost beaches were used predominantly by the animals during their annual fasts: the breeding and the moulting seasons. 相似文献
953.
The arbuscular mycorrhizal status of two plant species, Biscutella laevigata L. and Plantago lanceolata L., was investigated on calamine spoil mounds in Boles^aw (southern Poland). Although B. laevigata is a member of the Brassicaceae, a family generally accepted as non-mycorrhizal, this species formed AM symbioses on both heavy metal-contaminated and non-contaminated sites. Besides vesicles and coils, arbuscules were also observed, especially in roots collected prior to seed maturity. Relative mycorrhizal root length and relative arbuscular richness were usually much higher in P. lanceolata than in B. laevigata but not absolute arbuscule richness. Roots of P. lanceolata showed higher colonisation than B. laevigata. Although roots were collected from plants in close proximity, no correlation in mycorrhizal parameters was found between the two species. 相似文献
954.
Agnieszka Fischer Danuta Wiechuła Lidia Postek-Stefańska Jerzy Kwapuliński 《Biological trace element research》2009,132(1-3):19-26
The study shows the results of research on the concentrations of metals (Cd, Pb, Mn, Cu, Cr, Fe, Zn, Na, K, Mg, and Ca) in deciduous and permanent teeth with respect to their location in the oral cavity (maxilla, mandible). It has been found that the concentrations of metals were significantly higher in the deciduous teeth than in permanent ones. Regression analysis and principal component analysis revealed an increased dynamics of the processes of binding the elements by the hydroxyapatite of deciduous teeth. Higher concentrations of the metals were found in the maxilla permanent and deciduous teeth than in the mandible ones. 相似文献
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