Compositions, methods and systems for gas vesicle based cavitation

A method of applying a mechanical stress to a cavitation target in a target site, the method comprising:

• delivering to the target site containing the cavitation target one or more gas vesicles (GVs) having a GV type collapse threshold, the delivering positioning the GVs in proximity of the cavitation target, and applying ultrasound pulses to the target site after the delivering, the ultrasound pulses selected to both collapse the GV type by having a positive pressure above the GV type collapse threshold and to drive the cavitation of bubbles created by the GVs after collapse by negative pressure of the ultrasound pulses, the cavitated bubbles applying the mechanical stress to the cavitation target;
• wherein the gas vesicle comprises a variant GvpC engineered to comprise binding tags presented on the GVs and configured to bind to a target molecule on the cavitation target.