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91.
92.
Annelies Onraedt Cassandra De Muynck Bart Walcarius Wim Soetaert Erick Vandamme 《Biotechnology letters》2005,26(19):1481-1485
As a halotolerant bacterial species, Brevibacterium epidermis DSM 20659 can grow at relatively high salinity, tolerating up to 2 m NaCl. It synthesizes ectoine and the intracellular content increases with the medium salinity, with a maximum of 0.14 g ectoine/g CDW at 1 m NaCl. Sugar-stressed cells do not synthesize ectoine. Ectoine synthesis is also affected by the presence of external osmolytes. Added betaine is taken up and completely replaced ectoine, while l-proline is only temporarily accumulated after which ectoine is synthesized. The strain can metabolize ectoine; l-glutamate is a better carbon source for ectoine synthesis than l-aspartate. 相似文献
93.
Herein we describe a procedure for measuring the total light emission of the naturally bioluminescent tropical fungus Gerronema viridilucens and the optimization of culture conditions using multivariate factorial anova. Cultures growing on an agar surface in 35 mm Petri dishes at 90% humidity show optimal bioluminescence emission at 25 degrees C in the presence of 1.0% sugar cane molasses, 0.10% yeast extract and pH 6.0 (nonbuffered). Temperature and pH are the most important factors for both mycelial growth and bioluminescence. 相似文献
94.
Erick S. Van Dyke Dennis L. Scarnecchia Brian C. Jonasson Richard W. Carmichael 《Hydrobiologia》2009,625(1):27-42
Winter concealment habitat quality was assessed and its use by juvenile spring Chinook salmon (Oncorhynchus tshawytscha) quantified in three hatching areas of the Grande Ronde River Basin, Oregon USA. Fish densities were significantly higher
in pools with a higher winter concealment habitat index than pools with a lower index. The mean fork length and mean growth
rate of fish did not differ between pools with a higher or lower winter concealment habitat index, even though residual fish
were significantly larger than fish that emigrated. Biomass–density was significantly higher in pools with a higher winter
concealment habitat index than pools with a lower index in all three hatching areas. Biomass–density was positively associated
with the amount of cobble substrate (10–24.9 cm/m2) in all three hatching areas, and inversely associated with embeddedness in two of the hatching areas. Results of this study
indicate that enhancing winter concealment habitat could improve habitat quality resulting in increased carrying capacity
and winter usage by juvenile spring Chinook salmon.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Handling editor: J. A. Cambray 相似文献
95.
Maricel Alvarez Dries Huygens Erick Olivares Isabel Saavedra Miren Alberdi Eduardo Valenzuela 《Physiologia plantarum》2009,136(4):426-436
Drought stress conditions (DC) reduce plant growth and nutrition, restraining the sustainable reestablishment of Nothofagus dombeyi in temperate south Chilean forest ecosystems. Ectomycorrhizal symbioses have been documented to enhance plant nitrogen (N) and phosphorus (P) uptake under drought, but the regulation of involved assimilative enzymes remains unclear. We studied 1-year-old N. dombeyi (Mirb.) Oerst. plants in association with the ectomycorrhizal fungi Pisolithus tinctorius (Pers.) Coker & Couch. and Descolea antartica Sing. In greenhouse experiments, shoot and root dry weights, mycorrhizal colonization, foliar N and P concentrations, and root enzyme activities [glutamate synthase (glutamine oxoglutarate aminotransferase (GOGAT), EC 1.4.1.13-14), glutamine synthetase (GS, EC 6.3.1.2), glutamate dehydrogenase (GDH, EC 1.4.1.2-4), nitrate reductase (NR, EC 1.6.6.1), and acid phosphomonoesterase (PME, EC 3.1.3.1-2)] were determined as a function of soil-water content. Inoculation of N. dombeyi with P. tinctorius and D. antartica significantly stimulated plant growth and increased plant foliar N and P concentrations, especially under DC. Ectomycorrhizal inoculation increased the activity of all studied enzymes relative to non-mycorrhizal plants under drought. We speculate that GDH is a key enzyme involved in the enhancement of ectomycorrhizal carbon (C) availability by fuelling the tricarboxylic acid (TCA) cycle under conditions of drought-induced carbon deficit. All studied assimilative enzymes of the ectomycorrhizal associations, involved in C, N, and P transfers, are closely interlinked and interdependent. The up-regulation of assimilative enzyme activities by ectomycorrhizal fungal root colonizers acts as a functional mechanism to increase seedling endurance to drought. We insist upon incorporating ectomycorrhizal inoculation in existing Chilean afforestation programs. 相似文献
96.
Heather A. Rupp Thomas W. James Ellen D. Ketterson Dale R. Sengelaub Erick Janssen Julia R. Heiman 《Evolution and human behavior》2009,30(1):1-10
Women's preference for masculine faces varies with hormonal state, sociosexuality, and relationship status, but the underlying mechanisms are poorly understood. We hypothesized that hormones and psychosexual factors (sociosexuality, sexual inhibition/excitation) mediate the perception and evaluation of male faces thereby influencing women's preferences. We used functional magnetic resonance imaging to measure brain activity in 12 women as they evaluated pictures of male faces (half 30% masculinized, half 30% feminized). Participants were heterosexual women, age 23–28 years, who were not in a committed relationship and not using hormonal contraception. Women were tested during both the follicular and luteal phase of their menstrual cycle. We found five brain regions related to face and risk processing that responded more to the masculinized than to the feminized faces, including the superior temporal gyrus, precentral gyrus, posterior cingulate cortex, inferior parietal lobule, and anterior cingulate cortex. Increased activation in the anterior cingulate cortex, specifically, may indicate that women perceive masculinized faces to be both more risky and more attractive. We did not see any areas that were more strongly activated by feminized faces. Levels of activation were influenced by hormonal and psychosexual factors. The patterns of hormonally and psychosexually mediated neural activation observed may offer insight into the cognitive processes underlying women's partner preferences. 相似文献
97.
Fabrice Touzain Erick Denamur Claudine Médigue Valérie Barbe Meriem El Karoui Marie-Agnès Petit 《Genome biology》2010,11(4):R45
Background
Analysis of large scale diversity in bacterial genomes has mainly focused on elements such as pathogenicity islands, or more generally, genomic islands. These comprise numerous genes and confer important phenotypes, which are present or absent depending on strains. We report that despite this widely accepted notion, most diversity at the species level is composed of much smaller DNA segments, 20 to 500 bp in size, which we call microdiversity. 相似文献98.
Enrique Blanco Marina Ruiz-Romero Sergi Beltran Manel Bosch Adrià Punset Florenci Serras Montserrat Corominas 《BMC developmental biology》2010,10(1):94
Background
Regeneration is the ability of an organism to rebuild a body part that has been damaged or amputated, and can be studied at the molecular level using model organisms. Drosophila imaginal discs, which are the larval primordia of adult cuticular structures, are capable of undergoing regenerative growth after transplantation and in vivo culture into the adult abdomen. 相似文献99.
Wu B Barrios Sosa AC Boschelli DH Boschelli F Honores EE Golas JM Powell DW Wang YD 《Bioorganic & medicinal chemistry letters》2006,16(15):3993-3997
New 4-phenylamino-3-quinolinecarbonitriles with a 7-ethynyl group substituted by a pyridine, phenyl or thiophene ring containing basic water solubilizing groups were prepared and evaluated as Src kinase inhibitors. Of these new analogs, potent activity was observed with compounds having a (2,4-dichloro-5-methoxyphenyl)amino group at C-4, a methoxy or ethoxy group at C-6, and a pyridyl group bearing a dimethylamine or N-methylpiperazine on the ethynyl group at C-7. 相似文献
100.
Carla L. Black Pauline N. M. Mwinzi Erick M. O. Muok Bernard Abudho Colin M. Fitzsimmons David W. Dunne Diana M. S. Karanja W. Evan Secor Daniel G. Colley 《PLoS neglected tropical diseases》2010,4(3)