Public Key Encryption & pvt key Signing using Tyk

We have an endpoint API for which we don’t want our clients to request it directly. Instead we want to use a Tyk.

  1. Our end point API Gateway wishes to encrypt data by Public key and sign data by private key. I wish to configure both these keys for encryption and signing in v.
  2. Client will be passing Param1 and Value as xml string (eg. 1.02398238)
  3. Once this request comes to Tyk we want to encrypt this Param1 using Public Key which will be configured in the gateway & passed it as Param1 with this encrypted value to our endpoint API. We wish API Gateway now to sign this param1 value and create a signature using the configured private key and send this value as param2 to our endpoint API.

Can you please advise how this can be achieved specifically for encrypting public key and using our own private key for signing.