Phylloquinone is an important biological electron acceptor. Understanding how phylloquinone interacts with its local protein environment could lead to a deeper understanding of biological electron transfer involving this molecule. We have applied mid-IR spectroscopies and molecular dynamics simulations to phylloquinone in various hydrogen bonding solvents in order to gain further insight into the dynamics of hydrogen bonding interactions between phylloquinone and local protein environments. Our studies show that the local hydrogen bonding environment of phylloquinone can manifest itself as a shoulder in the carbonyl stretching region of phylloquinone. The amplitude of this shoulder is related to the average number of hydrogen bonds to the carbonyl units, where the average number of hydrogen bonds are extracted from molecular dynamics simulations. Combining the results of MD simulations and the experimental shoulder height, we have quantified the changes to the character of the normal modes in different hydrogen bonding environments using quantum mechanical methods. Further insight is gained from ultrafast mid-IR spectroscopies.

Quantifying hydrogen bonding of phylloquinone through theoretical methods and mid-IR spectroscopies

256th National Meeting (2018)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.