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941.
H. Kulig I. Kowalewska-Łuczak K. Żukowski W. Kruszyński 《Russian Journal of Genetics》2013,49(8):852-856
The aim of this study is to estimate the associations between the ANXA9, FABP3, and FABP4 genotypes and the breeding value for milk production traits (yields of milk, protein, and fat, as well as protein and fat percentage) in 975 Polish Holstein-Friesian cows. The frequencies of genotypes and alleles were determined. Statistically significant relations between the ANXA9 SNP and the breeding value for fat content, as well as the FABP4 SNP and the breeding value for protein content were found. The results indicated that selection for the ANXA9 GG and FABP4 GG animals might contribute to an decreased fat content and increased protein content in milk, respectively, in Polish Holstein-Friesian cows. Although verification in the further studies is needed. 相似文献
942.
[6-3H1] (24S)-24-Ethylcholesta-5,22,25-trien-3β-ol added to the growth medium of a culture of Trebouxia sp. 213/3 was efficiently taken-up by the cells and converted into (24R)-24-ethylcholesta-5,22-dien-3β-ol (poriferasterol) which is one of the major sterols of this alga. A cell-free homogenate was obtained from Trebouxia which catalysed the NADPH-dependent reduction of [6-3H1] (24S)-24-ethylcholesta-5,22,25-trien-3β-ol to yield poriferasterol. The δ25-sterol reductase was found to be mainly localized in the microsomal fraction of the homogenate. 相似文献
943.
944.
PAWEŁ JAŁOSZYŃSKI 《Systematic Entomology》2012,37(3):448-477
Neotropical genera of Cephenniini characterized by an additional leg ‘segment’ (‘trochantellus’) are revised, and the following new taxa are described: Shyri gen.n. , Shyri pichincha sp.n. (type species of Shyri) (Ecuador), Shyri perversus sp.n. (Ecuador), Shyri quitu sp.n. (Ecuador), Shyri microphthalmus sp.n. (Ecuador), Monstrophennium gen.n. (type species: Cephennium spinicolle Schaufuss), Furcodes gen.n. , Furcodes apicalis sp.n. (type species of Furcodes) (Mexico), Furcodes tutule sp.n. (Honduras), Paracephennium pumilio sp.n. (Costa Rica), Pseudocephennium iwokramanum sp.n. (Guyana), Pseudocephennium trilineatum sp.n. (Guyana), Pseudocephennium araguanum sp.n. (Venezuela), Pseudocephennium maximum sp.n. (Venezuela), Pseudocephennium peruvianum sp.n. (Peru), Pseudocephennium cochabambanum sp.n. (Bolivia), Pseudocephennium saramaccanum sp.n. (Suriname) and Pseudocephennium brokopondonum sp.n. (Suriname). Pseudocephennium spinicolle (Schaufuss) is transferred to Monstrophennium. Cladistic analysis of characters from adult morphology of all genera of Cephenniini and a large outgroup sample from Cyrtoscydmini, Eutheiini, Scydmaenini, Clidicini and Mastigini strongly supported the monophyly of Cephenniini. However, only the Cephennomicrus group comprising nine genera was strongly supported as a monophyletic clade, while only weak support was found for the previously suggested Cephennodes group and Cephennium group. Two alternative hypotheses concerning the phylogeny of Cephenniini are put forward and discussed: (i) the Cephennium group is sister to all remaining Cephenniini; or (ii) the Cephennomicrus group is sister to all remaining Cephenniini. The Neotropical genera with ‘trochantellus’ form a well‐supported clade derived from the ancestral lineage of the Cephennodes group. 相似文献
945.
Oleksy A Opaliński Ł Derewenda U Derewenda ZS Otlewski J 《The Journal of biological chemistry》2006,281(43):32891-32897
The Dbl homology nucleotide exchange factors (GEFs) activate Rho family cytosolic GTPases in a variety of physiological and pathophysiological events. These signaling molecules typically act downstream of tyrosine kinase receptors and often facilitate nucleotide exchange on more than one member of the Rho GTPase superfamily. Three unique GEFs, i.e. p115, PDZ-RhoGEF, and LARG, are activated by the G-protein coupled receptors via the Galpha(12/13), and exhibit very selective activation of RhoA, although the mechanism by which this is accomplished is not fully understood. Based on the recently solved crystal structure of the DH-PH tandem of PDZ-RhoGEF in complex with RhoA (Derewenda, U., Oleksy, A., Stevenson, A. S., Korczynska, J., Dauter, Z., Somlyo, A. P., Otlewski, J., Somlyo, A. V., and Derewenda, Z. S. (2004) Structure (Lond.) 12, 1955-1965), we conducted extensive mutational and functional studies of the molecular basis of the RhoA selectivity in PDZ-RhoGEF. We show that while Trp(58) of RhoA is intimately involved in the interaction with the DH domain, it is not a selectivity determinant, and its interaction with PDZ-RhoGEF is unfavorable. The key selectivity determinants are dominated by polar contacts involving residues unique to RhoA. We find that selectivity for RhoA versus Cdc42 is defined by a small number of interactions. 相似文献
946.
Electric field-induced absorption changes (electrochromism or Stark effect) of the light-harvesting PSII pigment-protein complexes LHCIIb, CP29, CP26 and CP24 were investigated. The results indicate the lack of strong intermolecular interactions in the chlorophyll a (Chl a) pools of all complexes. Characteristic features occur in the electronic spectrum of Chl b, which reflect the increased values of dipole moment and polarizability differences between the ground and excited states of interacting pigment systems. The strong Stark signal recorded for LHCIIb at 650-655 nm is much weaker in CP29, where it is replaced by a unique Stark band at 639 nm. Electrochromism of Chl b in CP26 and CP24 is significantly weaker but increased electrochromic parameters were also noticed for the Chl b transition at 650 nm. The spectra in the blue region are dominated by xanthophylls. The differences in Stark spectra of Chl b are linked to differences in pigment content and organization in individual complexes and point to the possibility of electron exchange interactions between energetically similar and closely spaced Chl b molecules. 相似文献
947.
948.
949.
Since temperament affects the development of social behaviours and interpersonal relations, the possible links between autistic traits and temperament are of particular interest. The purpose of the study was to explore the relationships between autistic traits and temperamental characteristics in the framework of the Regulative Temperament Theory by Strelau, and the Emotionality, Activity and Sociability theory by Buss and Plomin, with particular emphasis on gender differences. The Autism Spectrum Quotient (AQ), Formal Characteristics of Behaviour – Temperament Inventory and Temperament Survey for Adults were administered. The participants were 593 university students, including 364 females and 229 males. Results showed positive correlations between autistic traits and Emotional Reactivity, Perseveration, Distress, Fear and Anger, and negative correlations with Activity, Briskness, Endurance and Sociability. The results of multiple regression analyses involving the Autism Spectrum Quotient score as a dependent measure were different for females and males. Results of exploratory PCA analysis showed that AQ score, Sociability and Activity loaded one factor (with AQ loading being opposite to two others). High AQ scorers demonstrated higher Emotional Reactivity, Perseveration, Distress and Anger, and lower Briskness, Endurance, Activity and Sociability as compared to norms for the general population. In this study we showed that temperament measures were able to identify items that correlated in parts with autistic traits, while other items were obverse. The relationships between temperament and autistic traits differ slightly between genders. We assume that with regard to the broader autism phenotype, temperaments might be helpful in characterizing healthy control samples. 相似文献
950.
Activation of inhibitors by sortase triggers irreversible modification of the active site 总被引:1,自引:0,他引:1
Maresso AW Wu R Kern JW Zhang R Janik D Missiakas DM Duban ME Joachimiak A Schneewind O 《The Journal of biological chemistry》2007,282(32):23129-23139
Sortases anchor surface proteins to the cell wall of Gram-positive pathogens through recognition of specific motif sequences. Loss of sortase leads to large reductions in virulence, which identifies sortase as a target for the development of antibacterials. By screening 135,625 small molecules for inhibition, we report here that aryl (beta-amino)ethyl ketones inhibit sortase enzymes from staphylococci and bacilli. Inhibition of sortases occurs through an irreversible, covalent modification of their active site cysteine. Sortases specifically activate this class of molecules via beta-elimination, generating a reactive olefin intermediate that covalently modifies the cysteine thiol. Analysis of the three-dimensional structure of Bacillus anthracis sortase B with and without inhibitor provides insights into the mechanism of inhibition and reveals binding pockets that can be exploited for drug discovery. 相似文献