1st Year Ph.D student of Kanaya Lab.
Through the internship program for graduate students, I had earned valuable experience working with an excellent research group whose research area is related with mine dealing with peptidyl-prolyl isomerase (PPIase). I joined Prof. Gunter Fischer’s research group at Max Planck Research Unit for Enzymology and Protein Folding, Halle (Saale), Germany, which is known as the leader in PPIase’s research due to their success in identifying the first ever PPIase and in developing many techniques to characterize it. During the internship, I work with the characterization of PPIase activity and chaperone function of FKBP22. Dr. Cordelia Schiene-Fischer, as one of the group leader in Fischer’s research group, kindly and excellently supervised my lab works. I am proud to be supervised by her due to her great and long-standing achievements in this area of research. Having a working experience with their group is a valuable opportunity to acquire an extended knowledge of PPIase- related research.
Protease-free method, which is a novel method to characterize PPIase activity, was employed to determine the PPIase activity of SIB1 FKBP22 and its derivatives, due to the stability of FKBP22 against chymotrypsin. The method revealed that PPIase activity of SIB1 FKBP22 was 3-folds higher than that determined by protease coupling methods. Substrate specificity of SIB1 FKBP22 revealed that SIB1 FKBP22 behaves as other FKBP member, in which hydrophobic residues preceding proline are more preferable than polar or charged residues. Additionally, PPIase activity of monomeric (NNC) and R142A mutants, which are SIB1 FKBP22’s derivatives, were also being analyzed with protease-free method. NNC mutant exhibited a comparable activity to that of WT-SIB1 FKBP22, while the activity of R142A mutant was reduced by about 20%. The PPIase activity of WT-SIB1 FKBP22, NNC mutant, and R142A were inhibited by FK506 with IC50 values 77.50, 81.72 and 18.24 nM respectively. Additionally, the chaperone function had also been identified by the ability of FKBP22 to retard the Amyloid b fibril formation. In the presence of 5 μM of WT-FKBP22 fibril formation has been reduced up to 30%.
The program highly contributes to my recent project in Kanaya lab at the moment since some new techniques and information had been ?those results are new information for SIB1 FKBP22, which has been extensively studied in our lab. Some new techniques had been acquired through this program and would be useful for our future works.
I had not only experienced a great opportunity in scientific manner, but I also had cross-cultural experiences. I do believe, those experiences would important for our career in the future due to our adaptability to new environment. As Charles Darwin said, it is not the strongest of the species that survives, nor the most intelligent that survives. It is the one that is most adaptable to change.