Bielawski Joseph P, Dunn Katherine A, Sabehi Gazalah, Béjà Oded
Department of Biology, Dalhousie University, Halifax, NS, B3H 4J1, Canada.
Proc Natl Acad Sci U S A. 2004 Oct 12;101(41):14824-9. doi: 10.1073/pnas.0403999101. Epub 2004 Oct 4.
Proteorhodopsin, a retinal-binding protein, represents a potentially significant source of light-driven energy production in the world's oceans. The distribution of photochemically divergent proteorhodopsins is stratified according to depth. Here, we present evidence that such photochemical diversity was tuned by Darwinian selection. By using a Bayesian method, we identified sites targeted by Darwinian selection and mapped them to three-dimensional models of proteorhodopsins. We suggest that spectral fine-tuning results from the combined effect of amino acids that directly interact with retinal and those that influence the confirmation of the retinal-binding pocket.
视紫质是一种视网膜结合蛋白，是全球海洋中光驱动能量产生的潜在重要来源。光化学性质不同的视紫质的分布随深度分层。在此，我们提供证据表明这种光化学多样性是由达尔文选择调节的。通过使用贝叶斯方法，我们确定了受达尔文选择作用的位点，并将它们映射到视紫质的三维模型上。我们认为光谱微调是由直接与视黄醛相互作用的氨基酸以及影响视黄醛结合口袋构象的氨基酸共同作用的结果。
