Challenges and Opportunities for Exploring Differences in BltD Enzyme Oligomerization Across Multiple Bacterial Species
Abraham Conant, David Marczak, Alejandra Portillo, Jonathan Tam, Hazel N. Leiva Martel
Department of Chemistry & Biochemistry
Faculty Supervisor: Misty L. Kuhn
Protein oligomerization is impactful for understanding structural characteristics of proteins and can be used as a mechanism for regulating protein activity. One family of proteins that exhibit diverse oligomerization patterns are the polyamine acetyltransferases (PAATs). In our laboratory, we have selected the BltD subgroup of PAATs to further delve into their oligomerization patterns compared to what is known about other family members. BltD proteins acetylate polyamines, such as spermine and spermidine, and are important for bacterial sporulation. We have preliminary data that show BltD proteins from different bacterial species crystallize in different oligomeric states (e.g. monomer and domain-swapped dimer). However, we do not know if all oligomers are functionally viable or if a particular oligomeric state is required under specific cellular conditions. Furthermore, the oligomeric states of these proteins in solution are unknown. Therefore, in this study we utilized multiple approaches to try to discern what the most likely oligomeric states were for each protein in solution. Additionally, we analyzed their crystal structures to assess which residues potentially contribute to these oligomers. Ultimately, these results provide new knowledge about the evolution of oligomeric states across the polyamine family.
This study was funded in part by the National Institutes of Health Department of Health and Human Services, National Institute of General Medical Sciences under Award Number R35GM133506 (to MLK).