15,420 research outputs found
On the Covariant Quantization of the 2nd-Ilk Superparticle
This paper is devoted to the quantization of the second-ilk superparticle
using the Batalin-Vilkovisky method. We show the full structure of the master
action. By imposing gauge conditions on the gauge fields rather than on
coordinates we find a gauge-fixed quantum action which is free. The structure
of the BRST charge is exhibited and the BRST cohomology yields the same
physical spectrum as the light- cone quantization of the usual superparticle.Comment: 17 page
Transition of hemoglobin between two tertiary conformations: The transition constant differs significantly for the major and minor hemoglobins of the Japanese quail (Cortunix cortunix japonica)
We demonstrate that 5,5′-dithiobis(2-nitrobenzoate) – DTNB – reacts with only CysF9[93]β and CysB5[23]β among the multiple sulfhydryl groups of the major and minor hemoglobins of the Japanese quail (Cortunix cortunix japonica). Kequ, the equilibrium constant for the reaction,
does not differ very significantly between the two hemoglobins. It decreases 430-fold between pH≈5.6 and pH≈9: from a mean of 7±1 to a mean of 0.016±0.003. Quantitative analyses of the Kequ data based on published X-ray and temperature-jump evidence for a tertiary structure
transition in liganded hemoglobin enable the calculation of Krt, the equilibrium constant for the r←→t tertiary structure transition. Krt differs significantly between the two hemoglobins: 0.744±0.04 for the major, 0.401±0.01 for the minor hemoglobin. The mean pKas of the two groups
whose ionizations are coupled to the DTNB reaction are about the same as previously reported for mammalian hemoglobins
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