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51.
Inhibition of the Bacterial Cell Wall Synthesis in vitro by Enduracidin,a New Polypeptide Antibiotic
Michio Matsuhashi Ikuko Ohara Yoshihiro Yoshiyama 《Bioscience, biotechnology, and biochemistry》2013,77(1):134-137
Adenosine 5′-phosphosulfate (APS) kinase from a thermophilic bacterium, Bacillus st ear other mophilus, was purified to apparent homogeneity. The apparent molecular weight was 50 kDa, consisting of two 26-kDa subunits. The enzyme was very thermostable and lacked cysteine and methionine residues. Enzyme activity was more stimulated with Mn2 + , Zn2 +, or Co2 + than with Mg2 + and the Km for ATP and APS were 220 µM and 42 µM, respectively. 相似文献
52.
Ryohei Yamaoka Hiroshi Fukami Shoziro Ishii 《Bioscience, biotechnology, and biochemistry》2013,77(10):1971-1977
The sex pheromone produced by adult females of the potato tuberworm moth was isolated from unmated female moths reared in the laboratory. The gas Chromatographic and mass spectrometric data suggested the pheromone to be a tridecatrienyl acetate. The isolated pheromone was subjected to partial hydrogenation with hydrazine and hydrogen peroxide and subsequent ozonolysis to produce a mixture of ω-acetoxy-alkanals. They were identified by mass Chromatographic technique as 4-acetoxy-butanal, 7-acetoxy-heptanal, and 10-acetoxy-decanal respectively. Consequently, the pheromone was identified as 4,7,10-tridecatrienyl acetate except the geometric configuration. 相似文献
53.
Accurate prediction of the leaching requirements (Lr) of crops and striving to attain them is essential for efficient irrigation
water use. Solute modeling was extended to develop four Lr conceptual models that do not neglect solute reactions in the root-zone,
surface evaporation, and the influence of immobile wetted pore space. The models were based on: (i) the water movement equation
which included an exponential water-uptake function (-e) or the 40-30-20-10 water-uptake function (-4); (ii) the solute movement
equation for a reactive salt of a linear reaction term (the Lrchem-e and Lrchem-4 models); or the employment of output (salinity
of soil solution, EC vs concentration factor, CF) of the SAO comprehensive chemical model (the LrSAO-e and LrSAO-4 models);
and (iii) the inclusion of an effective soil solution volume in the transport equations. The root-zone average relative effective
soil solution volume νeff (L | L50, p) was of sigmoidal response to leaching fraction (L) with two adjustable parameters L50
and p; the root-zone average reduced retention coefficient decreased linearly with L; and salt concentration at soil surface
was related to salt concentration of irrigation water (ECi) by the fraction of irrigation water that evaporated (∈). The resulted
concentration profiles indicated the salt behaved as a conservative one down to a threshold depth (xs) below of which salt
was retained and precipitated. The depth of the conservative-salt front, xs increased with L and the 40-30-20-10 water-uptake
pattern overestimated the xs depth relative to the exponential pattern. Concentration profiles were integrated to compute
the root-zone average salinity, which was converted to crop salt-tolerance threshold (AE). The four conceptual models were
successfully calibrated using experimental AE/ECi vs. Lr data with the input parameter values: ς = 0.27, p = 1.44, L50 = 0.16,
ω = 2, and ∈ = 0 or 0.1 for the exponential or the 40-30-20-10 pattern, respectively; where ς is relative root length parameter
and ω is a weighing parameter. No significant difference existed between the four model correlations at the 0.05 level. The
four models require ECi and AE of the crop as input for Lr prediction. Sensitivity analysis revealed predicted Lr was sensitive
the least to error in ∈. For tolerant and moderately tolerant crops Lr was sensitive the most to ς, and for sensitive crops
to L50 and p. Model verification and validation were discussed. In deriving the present Lr models, no osmotic adjustment was
required and both the exponential and the 40-30-20-10 water uptake patterns were, equivalently, applicable.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Cynthia L. Deitrick Richard E. Katholi David J. Huddleston Kathy Hardiek Lucienne Burrus 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2001,751(2)
Vitamin B6, measured as pyridoxal 5′-phosphate (PLP), is a co-enzyme in the transsulfuration pathway of homocysteine metabolism. Since depletion of PLP has been suggested as an independent risk factor for coronary artery disease, PLP is frequently measured to guide patient care. By a change and utilization of an Aquasil C18 column and the addition of an acetonitrile clean-up gradient to the potassium phosphate, with sodium perchlorate and bisulfite buffer between samples we report the modification of a previously described method for analysis of PLP. The result is a more practical, efficient, reliable and robust method for daily clinical use. We also determined and report that it is critical to protect freshly prepared standard PLP samples from light exposure during assay preparation. 相似文献
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