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91.
The self-association of flavin mononucleotide (FMN(2-)) as determined by (1)H NMR shift measurements
The concentration dependence of the (1)H NMR chemical upfield shifts of the protons H6, H9, H7alpha, and H8alpha of the 7,8-dimethylisoalloxazine residue of flavin mononucleotide (FMN(2-)) has been measured and the self-stacking tendency of FMN(2-) was quantified with the isodesmic model of indefinite non-cooperative self-association. The stacking tendency of FMN(2-) is considerable and described in the concentration range of 0.0025-0.1 M with the indicated model by K = 27 +/- 15 M(-1) (25 degrees C; I = 0.1-0.3 M). This result is compared with related ones from the literature. The caveats regarding the self-stacking properties of FMN(2-) and their dependence on the concentration are discussed. 相似文献
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Markus V. Heppt Thomas K. Eigentler Katharina C. Kähler Rudolf A. Herbst Daniela Göppner Thilo Gambichler Jens Ulrich Edgar Dippel Carmen Loquai Beatrice Schell Bastian Schilling Susanne G. Schäd Erwin S. Schultz Fanny Matheis Julia K. Tietze Carola Berking 《Cancer immunology, immunotherapy : CII》2016,65(8):951-959
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Co-expression and promoter content analyses assign a role in biotic and abiotic stress responses to plant natriuretic peptides 总被引:1,自引:0,他引:1
Stuart Meier René Bastian Lara Donaldson Shane Murray Vladimir Bajic Chris Gehring 《BMC plant biology》2008,8(1):24
Background
Plant natriuretic peptides (PNPs) are a class of systemically mobile molecules distantly related to expansins. While several physiological responses to PNPs have been reported, their biological role has remained elusive. Here we use a combination of expression correlation analysis, meta-analysis of gene expression profiles in response to specific stimuli and in selected mutants, and promoter content analysis to infer the biological role of the Arabidopsis thaliana PNP, AtPNP-A. 相似文献96.
Impact of aeration and heme-activated respiration on Lactococcus lactis gene expression: identification of a heme-responsive operon 总被引:1,自引:0,他引:1
Pedersen MB Garrigues C Tuphile K Brun C Vido K Bennedsen M Møllgaard H Gaudu P Gruss A 《Journal of bacteriology》2008,190(14):4903-4911
Lactococcus lactis is a widely used food bacterium mainly characterized for its fermentation metabolism. However, this species undergoes a metabolic shift to respiration when heme is added to an aerobic medium. Respiration results in markedly improved biomass and survival compared to fermentation. Whole-genome microarrays were used to assess changes in L. lactis expression under aerobic and respiratory conditions compared to static growth, i.e., nonaerated. We observed the following. (i) Stress response genes were affected mainly by aerobic fermentation. This result underscores the differences between aerobic fermentation and respiration environments and confirms that respiration growth alleviates oxidative stress. (ii) Functions essential for respiratory metabolism, e.g., genes encoding cytochrome bd oxidase, menaquinone biosynthesis, and heme uptake, are similarly expressed under the three conditions. This indicates that cells are prepared for respiration once O(2) and heme become available. (iii) Expression of only 11 genes distinguishes respiration from both aerobic and static fermentation cultures. Among them, the genes comprising the putative ygfCBA operon are strongly induced by heme regardless of respiration, thus identifying the first heme-responsive operon in lactococci. We give experimental evidence that the ygfCBA genes are involved in heme homeostasis. 相似文献
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We are constantly exposed to a mixture of sounds of which only few are important to consider. In order to improve detectability
and to segregate important sounds from less important sounds, the auditory system uses different aspects of natural sound
sources. Among these are (a) its specific location and (b) synchronous envelope fluctuations in different frequency regions.
Such a comodulation of different frequency bands facilitates the detection of tones in noise, a phenomenon known as comodulation
masking release (CMR). Physiological as well as psychoacoustical studies usually investigate only one of these strategies
to segregate sounds. Here we present psychoacoustical data on CMR for various virtual locations of the signal by varying its
interaural phase difference (IPD). The results indicate that the masking release in conditions with binaural (interaural phase
differences) and across-frequency (synchronous envelope fluctuations, i.e. comodulation) cues present is equal to the sum
of the masking releases for each of the cues separately. Data and model predictions with a simplified model of the auditory
system indicate an independent and serial processing of binaural cues and monaural across-frequency cues, maximizing the benefits
from the envelope comparison across frequency and the comparison of fine structure across ears.
相似文献
Bastian EppEmail: |
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