Suppose, given an agent belonging to a company, having its own pair of public / private keys, that you want to certify with confidence that it was really that agent belonging to that company to have written through a particular transaction the data on the blockchain. In Ethereum, you could publish your address on the company website while, in Sawtooth, how could I do? Is it possible to use public key or is this not good for security reasons? Is this a suitable use case for Sawtooth?
The public key is for public good and there is no reason not to widely publish it and make it available.
The usual problem with public-private keypairs is people leak the private key or do not secure the private key properly and have it lost or stolen.