SOAPUI - Extracting data using jsonpath when element has space

I'm attempting to use jsonpath in SOAPUI to facilitate my testing.

I would like to transfer values using property transfer in SOAPUI from a response to a request, however the element has a space.

Below is a extract from the JSON response:

"Email address": "EwanWalker@dayrep.com",
"NameonCardLine2": null,

The expression I would use is as follows:

$.custCriteria.Email address

However this fails.