Procedure for testing kinetic models of the photocycle of bacteriorhodopsin.
Procedure for testing kinetic models of the photocycle of bacteriorhodopsin.
复制标题
测试细菌视紫红质光循环动力学模型的程序。
DOI：
10.1016/s0006-3495(82)84543-8
复制
发表时间：
1982
影响因子：
3.4
通讯作者：
Lozier,RH
中科院分区：
文献类型：
--
作者：
Nagle,JF;Parodi,LA;Lozier,RH
鉴于一些简单的动力学模型的光循环的细菌视紫红质（bR）和数据在许多波长和条件下，避免光选择和稳态循环并发症，它示出了如何提取的表观速率常数和光谱的中间体。特别考虑了建立这些结果的误差范围。有许多标准，我们明确讨论，光谱应该满足，以便动力学模型是可接受的。在15个测量波长和4个温度下获得了紫膜碎片在pH7.0的稀缓冲液中光循环的新数据。该程序，它可以推广到更复杂的模型，已被应用到这些数据来测试两种动力学模型：单向无分支模型和无方向模型与简单的分支直接回到bR从任何中间。在这些模型中，光谱的O中间体是高度温度敏感的，甚至与分支，和/或有两个广泛的最大值。此外，M中间体的光谱有一个次极大值，似乎需要两个类M态。因此，两种模型都不满足物理标准。
Given some simple kinetic models of the photocycle of bacteriorhodopsin (bR) and data taken at many wavelengths and under conditions that avoid photoselection and steady-state cycling complications, it is shown how to extract the apparent rate constants and the spectra of the intermediates. Special consideration was given to establishing the range of error of these results. There are many criteria, which we explicitly discuss, that the spectra should satisfy in order that the kinetic model be acceptable. New data for the photocycle of purple membrane fragments in dilute buffer at pH 7.0 has been obtained at 15 measuring wavelengths and four temperatures. The procedure, which can be generalized to more complex models, has been applied to these data to test two kinds of kinetic models: the unidirectional unbranched model and the undirectional model with simple branching straight back to bR from any intermediate. In these models the spectrum of the O intermediate is highly temperature sensitive, even with branching, and/or has two broad maxima. Moreover, the spectrum of the M intermediate has a secondary maximum and two M-like states appear to be required. Thus, neither model satisfies the physical criteria.