@phdthesis{Klein2021,
  author    = {Annelie Klein},
  title     = {pH affects the interaction of serin protease inhibitor Kazal type 1 (SPINK1) with trypsin: a single molecule force spectroscopy study},
  journal    = {pH beeinflusst die Interaktion zwischen serin protease inhibitor Kazal typ 1 (SPINK1) und Trypsin: eine Einzelmolek{\"u}l-Kraftspektroskopie Studie},
  url       = {https://nbn-resolving.org/urn:nbn:de:gbv:9-opus-47385},
  pages     = {44},
  year      = {2021},
  abstract  = {Serine protease inhibitor Kazal type 1 (SPINK1) plays an important role in preventing pancreatitis by inhibiting activated trypsin in the pancreas. The N34S variant of SPINK1 was found to be associated with chronic pancreatitis. However, this mutation is also expressed in the healthy population, indicating that the mutation alone does not cause the disease. In this study, we investigated at single molecular level the effect of pH on the binding characteristics of human cationic trypsin to SPINK1 by single-molecule force spectroscopy (SMFS). We found that at pH 8.0, trypsin shows twice the binding force to wild type SPINK1 (90.9 pN ± 3.9 pN) compared to the N34S mutant (47.3 pN ± 3.9 pN). An acidic pH of 4.8 results in a lower binding forces for trypsin-wild type SPINK1 (41.9 pN ± 4.0 pN) to a similar level as the binding force of trypsin-N34S mutant (54.6 pN ± 4.6 pN) complexes. These results are complemented by dynamic force spectroscopy findings which show a higher stability of the wild type SPINK1-trypsin complexes at pH 8.0 in comparison to N34S mutant-trypsin complexes. In addition, the binding profiles for both wild type and N34S mutant SPINK1 to trypsin equalize at pH 4.8. Our results indicate that the presence of the mutation in the healthy population would most probably not affect the interaction with trypsin at acidic pH such as physiological conditions in pancreatic acinar cells. However, an increase in pH, leads to a difference of binding strength between SPINK1 or N34S mutant towards human cationic trypsin. These findings may be relevant for understanding the role of SPINK1 and its mutation N34S in the pathogenesis of pancreatitis.},
  language  = {en}
}