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Responsive and functional microcapsules have many envisioned applications, spanning uses as diverse as drug delivery, cell protection, pollution mitigation, and cosmetics. The vastmajority of capsules are made from rigid cross-linked polymers ormetals that are strong but inflexible, restricting their applications in some sectors. There is then a strong need to develop flexible but robust structures using sustainable materials as a basis for new multifunctional capsules. Bacterial cellulose microcapsules have been developed with a highly flexible but strong fiber mesh structure that will enable engineering of new multifunctional capsule forms. The strong but sparse capsule structures possess key length scales from nanometers to millimeters and can be used as substrate for various surface modifications while still acting as flexible enclosures for chemical cargo. This work demonstrates three newuses of the particles: First, the low-density cellulose capsules are functionalized with metal organic framework (MOF)-enzyme groups that convert them into active particle motors, propelled by reaction with dissolved hydrogen peroxide. Unlike solid micromotors, the capsules can compress in response to confinement, using their surface reaction to navigate through narrow passages without damage. A second modification of the capsules by grafted poly-NIPAM makes the capsules temperature-responsive as well as tuning their permeability and elasticity. The highly elastic capsules can absorb and expel liquid during temperature-induced contraction and swelling, providing active uptake, release, and mixing of the liquid cargo. Finally, drying of the native bacterial cellulose microcapsules is studied to assess their ability to undergo extreme compression, store elastic energy, and mimic pollen’s self-sealing capabilities. In the course of the drying process, capillary forces induce stress leading to cellulose fiber alignment and pore closure and permanent deformation of the cellulose microcapsule. However, adding a negligible amount of biodegradable polymer like carboxymethyl cellulose prevents permanent bundling of the cellulose fibers. As a result, the millimeter-scale capsule converts to a nano-scale thin disk during drying but then recovers to its initial dimension by re-hydration, experiencing 1000 times change in volume. The modified bacterial cellulose microcapsule is proposed as a new class of soft and flexible multifunctional material capable of active motion, response, and deformation to supplement conventional microcapsules.