Figure 3.

(a) Western blots representing the proteolytic susceptibility of SM50 toward type VI collagenase and thermolysin developed using anti-SM50 polyclonal antibodies and protease contents of 10 (+) or 100 (++) μg/mL. (b) Time required for mineral nucleation in reference experiments (R) and in mineralization solutions containing only 1 mg/mL SM50 (−) and also supplemented with type VI collagenase. (c) Black bars represent the sequence coverage of SM50 proteolytic products produced by collagenase activity (box a). (d) Representative cryo-TEM images of mineral products formed in the presence of SM50 alone and in combination with a type VI collagenase. (e) Snapshots of mineralization reactions in the presence of the CTLD (Supplementary Video 1) or a SM50/type VI collagenase mixture acquired by using LC-STEM. Note the high aggregation propensity of vesicles and their hollow cores in the presence of collagenase. Scale bars represent (d) 500 (left) and 200 (right) nm and (e) 100 nm.