... Both transitions to latent and substrate forms were strongly but differently influenced by the amino-acid composition of the shutter region Surprisingly, we found that substitution of Lys335 to ... investigate the importance of the shutter region for the unique types of RCL insertion in PAI-1, we have now undertaken a number of substitutions in the shutter region and b strand 5A of PAI-1 and studied ... 8C [37] Therefore, to study the effect of shutter region substitutions on the transition of PAI-1 to a substrate form, we replaced the BSA in the assay buffer with 0.2% Triton X-100 The variants...