The Plausibility of Iron-Sulfur Peptides on the Early Earth

• Author / Creator

  Hu, Yin Juan

• Iron-sulfur clusters are recognized widely as ancient cofactors that are proposed to have impacted the prebiotic chemistry that led to life. Previous work done by our lab has shown that iron-sulfur clusters could be synthesized prebiotically on cysteine containing tripeptides, but it remains unclear if such complexes could survive under the environmental conditions of the early Earth.
  In this thesis, I investigated the stability of iron-sulfur peptides under prebiotically plausible environments. Seven different peptides with various sequences and lengths were used to synthesize iron-sulfur clusters, and these iron-sulfur peptides were tested under different chemical conditions. The results suggested that the types of iron-sulfur clusters formed are dependent on environmental conditions and the peptidyl ligands. Glutathione coordinated iron-sulfur clusters were the most stable among all conditions. The duplication of the tripeptide, i.e., a hexapeptide, would make the corresponding iron-sulfur clusters more stable. This demonstrated the possibility that modern iron-sulfur proteins could have emerged from short peptides that coordinated iron-sulfur clusters from the beginning, and thereby facilitated the emergence of primordial metabolic pathways that then give rise to the life.

• Subjects / Keywords

  • Chemistry
  • Origins of life
  • Iron-sulfur peptides

• Graduation date

  Spring 2022

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/r3-g2e0-r065

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.