WCF equivalent of InstanceContextMode and ConcurrencyMode in WebAPI

Hi,
  Is there any configuration equivalent to WCF configuration of InstanceContextMode = InstanceContextMode.Single, ConcurrencyMode = ConcurrencyMode.Single in WebAPI. I am trying to expose http endpoint by self host from already running WCF service. However, I have a requirement that all requests should be processed sequentially. 
 

If there is no existing setting, what should be quick /efficient way to do it(anything available in support to webapi ?).

 I looked at 2012 discussion thread , but like to check again if things have changed.
Thanks,