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81.
Thomas C. Ings José M. Montoya Jordi Bascompte Nico Blüthgen Lee Brown Carsten F. Dormann François Edwards David Figueroa Ute Jacob J. Iwan Jones Rasmus B. Lauridsen Mark E. Ledger Hannah M. Lewis Jens M. Olesen F.J. Frank van Veen Phil H. Warren Guy Woodward 《The Journal of animal ecology》2009,78(1):253-269
82.
Liane FM Finotelo Paulo JS Amaral Julio C Pieczarka Edivaldo HC de Oliveira Alcides Pissinati Michaela Neusser Stephan Müller Cleusa Y Nagamachi 《BMC evolutionary biology》2010,10(1):189
Background
The New World monkey (Platyrrhini) subfamily Pitheciinae is represented by the genera Pithecia, Chiropotes and Cacajao. In this work we studied the karyotypes of Pithecia irrorata (2n = 48) and Cacajao calvus rubicundus (2n = 45 in males and 2n = 46 in females) by G- and C-banding, NOR staining and chromosome painting using human and Saguinus oedipus whole chromosome probes. The karyotypes of both species were compared with each other and with Chiropotes utahicki (2n = 54) from the literature. 相似文献83.
Thomas C. Ings Lars Chittka 《Proceedings. Biological sciences / The Royal Society》2009,276(1664):2031-2036
Predators of pollinators can influence pollination services and plant fitness via both consumptive (reducing pollinator density) and non-consumptive (altering pollinator behaviour) effects. However, a better knowledge of the mechanisms underlying behaviourally mediated indirect effects of predators is necessary to properly understand their role in community dynamics. We used the tripartite relationship between bumblebees, predatory crab spiders and flowers to ask whether behaviourally mediated effects are localized to flowers harbouring predators, or whether bees extend their avoidance to entire plant species. In a tightly controlled laboratory environment, bumblebees (Bombus terrestris) were exposed to a random mixture of equally rewarding yellow and white artificial flowers, but foraging on yellow flowers was very risky: bees had a 25 per cent chance of receiving a simulated predation attempt by ‘robotic’ crab spiders. As bees learnt to avoid ‘dangerous’ flowers, their foraging preferences changed and they began to visit fewer yellow flowers than expected by chance. Bees avoided spider-free yellow flowers as well as dangerous yellow flowers when spiders were more difficult to detect (the colour of yellow spiders was indistinguishable from that of yellow flowers). Therefore, this interaction between bee learning and predator crypsis could lead flower species harbouring cryptic predators to suffer from reduced reproductive success. 相似文献
84.
Shechinah Felice Choragudi Ganesh Kumar Veeramachaneni BV Raman Bondili JS 《Bioinformation》2014,10(8):507-511
Endo- β-N-acetylgucosaminidases (ENGases) are the enzymes that catalyze both hydrolysis and
transglycosylation reactions. It is of interest to study ENGases because of their ability to synthesize glycopeptides.
Homology models of Human, Arabidopsis thaliana and Sorghum ENGases were developed and their active sites
marked based on information available from Arthrobacter protophormiae (PDB ID: 3FHQ) ENGase. Further, these
models were docked with the natural substrate GlcNAc-Asn and the inhibitor Man3GlcNAc-thiazoline. The catalytic
triad of Asn, Glu and Tyr (N171, E173 and Y205 of bacteria) were found to be conserved across the phyla. The crucial
Y299F mutation showing 3 times higher transglycosylation activity than in wild type Endo-A is known. The hydrolytic
activity remained unchanged in bacteria, while the transglycosylation activity increased. This Y to F change is found
to be naturally evolved and should be attributing higher transglycosylation rates in human and Arabidopsis thaliana
ENGases. Ligand interactions Ligplots revealed the interaction of amino acids with hydrophobic side chains and polar
uncharged side chain amino acids. Thus, structure based molecular model-ligand interactions provide insights into
the catalytic mechanism of ENGases and assist in the rational engineering of ENGases. 相似文献
85.