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951.
952.
Glycogen is accumulated during the latter half of the diel cycle in Synechococcus sp. strain WH8103 following a midday maximum in glgA (encoding glycogen synthase) mRNA abundance. This temporal pattern is quite distinct from that of Prochlorococcus and may highlight divergent regulatory control of carbon/nitrogen metabolism in these closely related picocyanobacteria. 相似文献
953.
Tobias Heinze Hanno Bährs Matthias Gilbert Christian E. W. Steinberg Christian Wilhelm 《Hydrobiologia》2012,684(1):215-224
Humic substances (HSs) have been shown to influence growth, photophysiology, and redox homeostasis in phototrophs. However, many ecological studies deliver controversial results indicating inhibitory or stimulating effects depending on the kind of phototrophic organism or type of HSs applied. Here we analyzed the effect of Huminfeed® (HF), a preparation from leonardite associated with lignite deposits, on growth and photosynthetic performance of three different coccal green algae. Concentrations of HF in the range of 2–20 mg l?1 dissolved organic carbon (DOC) did neither affect the growth rate nor the light-adapted photosynthetic electron transport. Even photoinhibitory light intensities of 1,600 μmol photons m?2 s?1, representing the tenfold of growth light intensity, did not result in a decline of the maximal photosynthetic rate in HF-treated algae. In HF-grown algae, a very subtle decrease by about 10% could be observed in thermoluminescent light emission, a sensitive method to detect changes in photosystem II (PSII) chemistry. However, thermoluminescence (TL) represents only 3% of the light-induced charge separated states in PSII. Hence, rather small changes will not have significant effects on overall photosynthetic performance and growth. Therefore, the physiological effect of HSs on freshwater phototrophs has to be revisited. 相似文献
954.
Amari M Laguerre S Vuillemin M Robert H Loux V Klopp C Morel S Gabriel B Remaud-Siméon M Gabriel V Moulis C Fontagné-Faucher C 《Journal of bacteriology》2012,194(6):1608-1609
Weissella confusa is a rod-shaped heterofermentative lactic acid bacterium from the family of Leuconostocaceae. Here we report the draft genome sequence of the strain W. confusa LBAE C39-2 isolated from a traditional French wheat sourdough. 相似文献
955.
Schutzer SE Fraser-Liggett CM Qiu WG Kraiczy P Mongodin EF Dunn JJ Luft BJ Casjens SR 《Journal of bacteriology》2012,194(2):545-546
It has been known for decades that human Lyme disease is caused by the three spirochete species Borrelia burgdorferi, Borrelia afzelii, and Borrelia garinii. Recently, Borrelia valaisiana, Borrelia spielmanii, and Borrelia bissettii have been associated with Lyme disease. We report the complete genome sequences of B. valaisiana VS116, B. spielmanii A14S, and B. bissettii DN127. 相似文献
956.
957.
Foulquier F Amyere M Jaeken J Zeevaert R Schollen E Race V Bammens R Morelle W Rosnoblet C Legrand D Demaegd D Buist N Cheillan D Guffon N Morsomme P Annaert W Freeze HH Van Schaftingen E Vikkula M Matthijs G 《American journal of human genetics》2012,91(1):15-26
Protein glycosylation is a complex process that depends not only on the activities of several enzymes and transporters but also on a subtle balance between vesicular Golgi trafficking, compartmental pH, and ion homeostasis. Through a combination of autozygosity mapping and expression analysis in two siblings with an abnormal serum-transferrin isoelectric focusing test (type 2) and a peculiar skeletal phenotype with epiphyseal, metaphyseal, and diaphyseal dysplasia, we identified TMEM165 (also named TPARL) as a gene involved in congenital disorders of glycosylation (CDG). The affected individuals are homozygous for a deep intronic splice mutation in TMEM165. In our cohort of unsolved CDG-II cases, we found another individual with the same mutation and two unrelated individuals with missense mutations in TMEM165. TMEM165 encodes a putative transmembrane 324 amino acid protein whose cellular functions are unknown. Using a siRNA strategy, we showed that TMEM165 deficiency causes Golgi glycosylation defects in HEK cells. 相似文献
958.
Duong TA de Beer ZW Zanzot JW Wingfield MJ Wingfield BD 《American journal of botany》2012,99(5):e216-e219
? Premise of the study: Polymorphic microsatellite markers were developed for the pine-infecting fungus, Grosmannia alacris. ? Methods and Results: Sixteen microsatellite markers were developed by using inter-simple sequence repeat (ISSR)-PCRs and 454 sequencing methods. Seven of these markers showed polymorphisms for a South African population of G. alacris, and 13 markers showed polymorphism when European isolates were included. Most of the primer pairs also amplified four closely related species: G. serpens, Leptographium gibbsii, L. castellanum, and L. yamaokae. ? Conclusions: These new markers will be useful for population studies of G. alacris and other species in the G. serpens complex. 相似文献
959.
Coevolutionary arms races are a powerful force driving evolution, adaptation, and diversification. They can generate phenotypic polymorphisms that render it harder for a coevolving parasite or predator to exploit any one individual of a given species. In birds, egg polymorphisms should be an effective defense against mimetic brood parasites and are extreme in the African tawny-flanked prinia (Prinia subflava) and its parasite, the cuckoo finch (Anomalospiza imberbis). Here we use models of avian visual perception to analyze the appearance of prinia and cuckoo finch eggs from the same location over 40 years. We show that the two interacting populations have experienced rapid changes in egg traits. Egg colors of both species have diversified over time, expanding into avian color space as expected under negative frequency-dependent selection. Egg pattern showed signatures of both frequency-dependent and directional selection in different traits, which appeared to be evolving independently of one another. Host and parasite appear to be closely tracking one another's evolution, since parasites showed closer color mimicry of contemporaneous hosts. This correlational evidence suggests that hosts and parasites are locked in an ongoing arms race in egg appearance, driven by constant change in the selective advantage of different phenotypes, and that coevolutionary arms races can generate remarkably rapid phenotypic change. 相似文献
960.
Isabelle Audo Kinga Bujakowska Elise Orhan Charlotte M. Poloschek Sabine Defoort-Dhellemmes Isabelle Drumare Susanne Kohl Tien D. Luu Odile Lecompte Eberhart Zrenner Marie-Elise Lancelot Aline Antonio Aurore Germain Christelle Michiels Claire Audier Mélanie Letexier Jean-Paul Saraiva Bart P. Leroy Christina Zeitz 《American journal of human genetics》2012,91(1):209