Scholarlink

<p>The cyanobacteriochromes are characterized by chromophores that are akin to phytochromes, but with a much larger variability in their spectral characteristics. In this study, we aim to unearth the reason for this increased variability in their spectral features. We employ a combination of high-level quantum mechanical and molecular mechanical calculations for this purpose. Quite surprisingly, we observe that instead of the electrostatic effect, it is predominantly the cavity effect of the protein that brings about a structural change of the chromophore, leading to a spectral shift. We also attempt to decipher the individual contribution of the amino acid residues near the cavity, which interact significantly with the chromophore. Understanding the subtle details will help these photoreceptor proteins to emerge as a promising source of optogenetic tools in near future.</p> Graphical abstract <p>In this work we have elucidated the spectral tuning mechanism in a cyanobacteriochrome. The blue shift of absorption spectra is governed by the structural effect of the protein rather than the electrostatic effect. We have proposed a general protocol to calculate this spectral shift using hybrid QM/MM approaches in photoreceptors.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Spectral tuning in cyanobacteriochrome

  • 期刊论文

  • 发表日期：

    2026年5月22日

查看全文
  • Samidh Ghosh,
  • Pradipta Dey,
  • Debashree Ghosh

摘要

The cyanobacteriochromes are characterized by chromophores that are akin to phytochromes, but with a much larger variability in their spectral characteristics. In this study, we aim to unearth the reason for this increased variability in their spectral features. We employ a combination of high-level quantum mechanical and molecular mechanical calculations for this purpose. Quite surprisingly, we observe that instead of the electrostatic effect, it is predominantly the cavity effect of the protein that brings about a structural change of the chromophore, leading to a spectral shift. We also attempt to decipher the individual contribution of the amino acid residues near the cavity, which interact significantly with the chromophore. Understanding the subtle details will help these photoreceptor proteins to emerge as a promising source of optogenetic tools in near future.

Graphical abstract

In this work we have elucidated the spectral tuning mechanism in a cyanobacteriochrome. The blue shift of absorption spectra is governed by the structural effect of the protein rather than the electrostatic effect. We have proposed a general protocol to calculate this spectral shift using hybrid QM/MM approaches in photoreceptors.