Revealing the reaction path of UVC bond rupture in cyclic disulfides with ultrafast x-ray scattering.
Lingyu Ma, Wenpeng Du, Haiwang Yong, Brian Stankus, Jennifer M Ruddock, Andrés Moreno Carrascosa, Nathan Goff, Yu Chang, Nikola Zotev, Darren Bellshaw, Thomas J Lane, Mengning Liang, Sébastien Boutet, Sergio Carbajo, Joseph S Robinson, Jason E Koglin, Michael P Minitti, Adam Kirrander, Theis I Sølling, Peter M Weber
Author Information
Lingyu Ma: Department of Chemistry, Brown University, Providence, RI, USA. ORCID
Wenpeng Du: Department of Chemistry, Brown University, Providence, RI, USA. ORCID
Haiwang Yong: Department of Chemistry and Biochemistry, University of California, San Diego, CA, USA. ORCID
Brian Stankus: Department of Chemistry, Western Connecticut State University, Danbury, CT, USA.
Jennifer M Ruddock: Department of Chemistry, Brown University, Providence, RI, USA. ORCID
Andrés Moreno Carrascosa: Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, Oxford, UK. ORCID
Nathan Goff: Department of Chemistry, Brown University, Providence, RI, USA. ORCID
Yu Chang: Department of Chemistry, Brown University, Providence, RI, USA.
Nikola Zotev: Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, Oxford, UK.
Darren Bellshaw: Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, Oxford, UK.
Thomas J Lane: Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA, USA. ORCID
Mengning Liang: Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA, USA. ORCID
Sébastien Boutet: Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA, USA. ORCID
Sergio Carbajo: Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA, USA. ORCID
Joseph S Robinson: Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA, USA. ORCID
Jason E Koglin: Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA, USA. ORCID
Michael P Minitti: Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA, USA. ORCID
Adam Kirrander: Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, Oxford, UK. ORCID
Theis I Sølling: Center for Integrative Petroleum Research, College of Petroleum & Geosciences, King Fahd University of Petroleum & Minerals, Dhahran 31261, Saudi Arabia.
Peter M Weber: Department of Chemistry, Brown University, Providence, RI, USA. ORCID
Disulfide bonds are ubiquitous molecular motifs that influence the tertiary structure and biological functions of many proteins. Yet, it is well known that the disulfide bond is photolabile when exposed to ultraviolet C (UVC) radiation. The deep-UV-induced S─S bond fragmentation kinetics on very fast timescales are especially pivotal to fully understand the photostability and photodamage repair mechanisms in proteins. In 1,2-dithiane, the smallest saturated cyclic molecule that mimics biologically active species with S─S bonds, we investigate the photochemistry upon 200-nm excitation by femtosecond time-resolved x-ray scattering in the gas phase using an x-ray free electron laser. In the femtosecond time domain, we find a very fast reaction that generates molecular fragments with one and two sulfur atoms. On picosecond and nanosecond timescales, a complex network of reactions unfolds that, ultimately, completes the sulfur dissociation from the parent molecule.
References
J Am Chem Soc. 2012 Dec 19;134(50):20279-81
[PMID: 23210550]
