Journal
SCIENCE
Volume 356, Issue 6344, Pages 1276-+Publisher
AMER ASSOC ADVANCEMENT SCIENCE
DOI: 10.1126/science.aam6203
Keywords
-
Categories
Funding
- U.S. Department of Energy (DOE), Office of Science, Office of Basic Energy Sciences [DE-AC02-76SF00515]
- DOE Office of Biological and Environmental Research
- National Institutes of Health, National Institute of General Medical Sciences [P41GM103393]
- National Institute of General Medical Sciences of the National Institutes of Health [R01GM040392]
- Atomic, Molecular, and Optical Sciences program within the Chemical Sciences, Geosciences, and Biosciences Division of the Office of Basic Energy Sciences, Office of Science, DOE
- Swiss National Science Foundation [158890]
Ask authors/readers for more resources
The multifunctional protein cytochrome c (cyt c) plays key roles in electron transport and apoptosis, switching function by modulating bonding between a heme iron and the sulfur in a methionine residue. This Fe-S(Met) bond is too weak to persist in the absence of protein constraints. We ruptured the bond in ferrous cyt c using an optical laser pulse and monitored the bond reformation within the protein active site using ultrafast x-ray pulses from an x-ray free-electron laser, determining that the Fe-S(Met) bond enthalpy is similar to 4 kcal/mol stronger than in the absence of protein constraints. The 4 kcal/mol is comparable with calculations of stabilization effects in other systems, demonstrating how biological systems use an entatic state for modest yet accessible energetics to modulate chemical function.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available