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21.
Growth and extracellular polysaccharide production byPorphyridium cruentum were measured as a function of several culture parameters. Photon flux density of 75 μmol m−2 s−1 and CO2 concentration of 2.5% were found to be optimum for both growth and extracellular polysaccharide production. Interactive studies
on these two parameters further confirmed that at these levels of photon flux density and CO2, when applied together, both growth (5.9·107 cells per mL) and extracellular polysaccharide production (1.9 g/L) were at the maximum. Maximum growth and extracellular
polysaccharide production were observed at inoculum density of 106 cells per mL and aeration rate of 500 mL air per min per liter. 相似文献
22.
Binding of [125I]calmodulin was characterized in highly purified synaptic plasma membrane (SPM) prepared from rat brain. By Scatchard analysis, the Ca2+-dependent membrane binding of [125I]calmodulin was found to have a Bmax of 284 pmol/mg protein and an apparent affinity with a Kd of 131 nM. Kinetic analysis indicates that at 37°C, the dissociation of [125I]calmodulinmembrane complexes follows first-order reaction and consists of two components: a dissociation constant (k) of 3.7×10–1 min–1 and a half-time (t1/2) of 1.8 min for the fast component, and a k of 4.8×10–2 min–1 and a t1/2 of 14.5 min for the slow component. At 0°C, substantial dissociation still occurred, with a k of 4.5×10–2 min–1 and a t1/2 of 15.3 min for the fast component, and a k of 5.5×10–3 min–1 and a t1/2 of 125.5 min for the slow component. These data on binding affinity and dissociation kinetics are consistent with the notion that SPM can readily and rapidly associated and dissociate calmodulin. In Arrhenius analysis of temperature effects, [125I]calmodulin binding to SPM exhibits a biphasic function, with the transition temperature (Td) estimated to be 23.8°C, suggesting that binding is influenced by lipid phase transition of the membrane. The binding of [125I]calmodulin to the synaptic membrane was found to be increased by corticosterone (10–7–10–6 M), a steroid hormone, and decreased by ethanol (50–200 mM), a centrally acting drug. Our data on the characteristics of calmodulin binding to the SPM provide groundwork for future studies on physiological and pharmacological regulation of calmodulin translocation to and from the plasma membrane in synaptic terminals.Abbreviations used CaM
calmodulin
- SPM
synaptic plasma membrane
- ATPase
adenosine triphosphatase
- Tris
tris(hydroxymethyl)aminomethane
- EGTA
ethylene-bis(oxyethylenenitrilo)tetraacetic acid
- SDS
sodium dodecyl sulfate
- TFP
trifluoperazine
- Kd
dissociation constant
- Bmax
maximum binding
- k
first-order rate constant
- t1/2
half-time
- Td
transition temperature 相似文献
23.
Mammalian Genome - Type 2 diabetes (T2D) is a metabolic disease with an imbalance in blood glucose concentration. There are significant studies currently showing association between T2D and... 相似文献
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Md. Aktar-Uz-Zaman Md. Ariful Islam Md. Shahin Iqbal Md. Jahangir Alam Debashish Sarkar Bander Albogami Ahmed Gaber Akbar Hossain 《Phyton》2023,92(3):883-899
Ensuring food security for the rapidly increasing population and changing climatic scenarios are requisites for
exploiting the genetic divergence of food crops. A study was undertaken to sort out an early maturing chickpea
variety for fitting easily between rice-rice cropping systems in the Eastern Indo-Gangetic Plain of Bangladesh. The
trial was comprised of eight elite lines of chickpea and executed at various localities in Bangladesh from 2014–
15 to 2017–18. The result explored the chickpea genotype, BARI Chola-11 remained superior to the rest of
the elite genotypes for having a short maturity period (100–106 days), and lesser days to 50% flowering (47–
55 days). The same genotype was recorded to have robust vegetative and reproductive yield attributes including
plant height (49–57 cm), podsplant−1 (37–50), and optimum 100 seed weight (19.5–20.6 g). Owing to better yield
attributes, BARI Chola-11 resulted in the maximum seed yield (1200–1500 kg ha−1
) of chickpea and might be
recommended for general adoption in the region for boosting nutritional security status through improved productivity under changing climate. 相似文献
26.
Shafiq Fahad Iqbal Muhammad Raza Syed Hammad Akram Nudrat Aisha Ashraf Muhammad 《Journal of Plant Growth Regulation》2023,42(3):1267-1290
Journal of Plant Growth Regulation - Fullerenols are carbon nanoparticles that have been declared as free radical sponges. There is a need to take a prudent path toward its applications in various... 相似文献
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Khalid Meksem Dario Leister Johan Peleman Marc Zabeau Francesco Salamini Christiane Gebhardt 《Molecular & general genetics : MGG》1995,249(1):74-81
The R1 allele confers on potato a race-specific resistance to Phytophthora infestans. The corresponding genetic locus maps on chromosome V in a region in which several other resistance genes are also located. As part of a strategy for cloning R1, a high-resolution genetic map was constructed for the segment of chromosome V that is bordered by the RFLP loci GP21 and GP179 and includes the R1 locus. Bulked segregant analysis and markers based on amplified fragment length polymorphisms (AFLP markers) were used to select molecular markers closely linked to R1. Twenty-nine of approximately 3200 informative AFLP loci displayed linkage to the R1 locus. Based on the genotypic analysis of 461 gametes, eight loci mapped within the GP21–GP179 interval. Two of those could not be seperated from R1 by recombination. For genotyping large numbers of plants with respect to the flanking markers GP21 and GP179 PCR based assays were also developed which allowed marker-assisted selection of plants with genotypes Rr and rr and of recombinant plants. 相似文献
30.